Effects of Pteronia incana (Blue bush) invasion on grass biomass production, soil chemical
characteristics and peoples’ livelihoods in Ngqushwa communal rangelands, Eastern
Cape.
A dissertation submitted in partial fulfillment of the of the requirement of the Degree of
Masters of Science in Agriculture (Pasture Science)
Department of Livestock and Pasture
Faculty of Science and Agriculture
The University of Fort Hare
By
T. NTUTHA
Supervisor: Prof. T.B. Solomon
Co-supervisor: Dr. K. Mopipi
2016 Declaration
I declare that “Effects of Pteronia incana (Blue bush) invasion on grass biomass production, soil chemical characteristics and peoples’ livelihoods in Ngqushwa communal rangelands, Eastern Cape” is my own work and has not been submitted to any institution and all the sources used have been properly cited and acknowledged by complete reference.
Mr Ntutha Thando Date
Approved as to style content by:
Prof. S.T. Beyene (Supervisor) Dr K. Mopipi (Co-supervisor)
i
Abstract The objective of the study was to assess the farmers’ knowledge and perceptions of P. incana invasion and impacts on rangeland, livestock production and livelihood in four communal grazing areas. Twenty households per village that own livestock were randomly selected to conduct an interview using an open and closed ended questionnaire. In each household, an old and knowledgeable respondent about P. incana invasion was used as a selection criterion. For scientific assessment of range condition, the experiment was conducted in a 270 m x 100 m trial plots that were established in 2014. The area was divided into 3 open and 3 fenced subplots each having an area of 45 m x 100 m established laid down a slope gradient. Each plot was divided into four equal subplots to apply the control treatments. Therefore, the trial layout was a stratified block experiment of four treatments replicated three times. The four control treatments applied to P. incana invasion were chopping and resting (CR), resting without chopping (RWOC), grazing and chopping (GC), grazing without chopping (GWOC). A step point method was applied in each transect to monitor species composition and P. incana cover.
On the fenced plots two exclosures of 1mx1m size were randomly distributed to make sure that resting is maintained. Within exclosures 0.25 m2quadrates in each were put randomly to measure biomass. Density of P. incana was determined from 5 m x 5 m quadrates that were placed randomly within each sub-plot. The density and height of individual shrub plant was measured. All rooted live woody plants were recorded and counted in each quadrate. The results revealed that species composition was not affected (P>0.05) by the treatments applied.
The herbage height and basal cover had greater values (P<0.05) under rested plus chopping
(CR) treatment followed by grazed plus chopping (GC). Grass biomass production and essential nutrients showed a greater concentration (P<0.05) under CR treatment than any treatments applied. The results on perceptions revealed that goats had the highest mean household holding number than any other livestock species across the selected villages in all the villages. Respondents indicated that both goats and cattle had equal or more importance
ii than sheep. Three out of four villages raised cattle primarily for income generation and secondarily for cultural purposes like slaughtering during weddings ceremonies, amazila and also during woman circumcisions (Ntonjane). Similarly, goats and sheep were primarily raised for cash income generation. The results revealed that livestock population decreased over ten to twenty years (one-two decades) and poor rangeland condition is assumed to be the cause of the situation as feed is the key factor for production. The area was dominated by the grasses rather than by browse woody species so the above results are possible as the P. incana is more competitive than grasses. It was concluded that P. incana is detrimental to both rangeland and animal production. Forage and animal performance as well as farmers’ economic status
(livelihoods) were negatively affected by P. incana invasion and the scientific assessment reported it to be detrimental to agriculture. Thus chopping and resting (CR) treatment resulted in a greater improvement of the basal cover, biomass production, soil nutrients as well as grass height than the other treatments applied. Therefore it can be concluded that chopping and resting the veld invaded with P. incana can improve the range and consequently animal production.
Key words: Grazing management, Supplementation, Shrub invasion, Poverty, Minerals and
Degradation.
iii
Dedication This dissertation is dedicated to my parents, Mother (Nobulele Tembisa Ntutha) and Dad
(Mabhulwana Ntutha) and Aunt (Bongiwe Novusile Nomvete) as well as my siblings.
iv
Acknowledgement I would like to thank Prof. S.T. Beyene for his tireless and perseverance in supervision and co- supervision by Dr K. Mopipi up until the submission of this dissertation, if it was not for you,
I would never have been academically where I am today, I thank you Prof and Doctor.
I am sincerely appreciative to Dohne, the Agricultural Development Institute for allowing this study to be conducted on their sites and also for their support with some of the material used in this research. I am thankful to the technicians in the University for their Support (Mr Sibanga
W. Monwabisi and Nyanga Mweli). I am appreciative to my fellow colleagues for their assistance from the start of data collection till the end. I am also sincerely thankful to the
National Research Foundation (NRF) and Govan Mbeki Research and Development Center for funding this study.
v
Contents Declaration ...... i
Abstract ...... ii
Dedication ...... iv
Acknowledgement ...... v
List of Appendices ...... ix
List of tables ...... x
List of Figures ...... xii
List of abbreviations ...... xiii
Chapter 1. Introduction ...... 1
1.1Background ...... 1
1.2 Problem statement ...... 3
1.3 Justification ...... 3
1.4 Objectives ...... 4
General objective ...... 4
Specific objective ...... 4
Chapter 2 Literature review ...... 5
2. 1 Introduction ...... 5
2.2 Causes of P. incana invasion...... 6
2.2.1 Landscape and soil related factors ...... 6
2.2.2 Climate related factors...... 7
2.2.3 Grazing as a factor of shrub invasion ...... 8
2.2.4 Fire as a factor of invasion ...... 8
2.3 Effects of shrub invasion ...... 9
2.3.1 Effects of shrub invasion on livestock production ...... 9
2.3.2 Effects of shrub invasion on vegetation ...... 9
vi
2.3.3 Effects of shrub invasion on soil water ...... 10
2.3.4 Effects of shrub invasion on people’s livelihoods ...... 11
2.4 Effects or role of shrub invasion on land degradation ...... 11
2.5 Extent of shrub invasion in South Africa ...... 12
2.6 Perceptions of communal farmers on the situation of shrub invasion ...... 13
2.7. Summary ...... 15
References ...... 16
Chapter 3: Assessment of farmer’s knowledge and perception of Pteronia incana invasion and its impacts on livelihoods in four communal areas of Ngqushwa, Eastern Cape...... 29
Abstract ...... 29
3.2 Introduction...... 30
3.2 Materials and Methods ...... 31
3.2.1 Description of the study area ...... 31
3.3 Results and discussion...... 33
3.3.1 Demographic information...... 33
3.4 Conclusion ...... 53
3.5. Recommendation...... 53
References ...... 54
Chapter 4: Effects of Pteronia incana (Blue bush) invasion on grass biomass production, species distribution and soil chemical characteristics under systematic control methods...... 62
Abstract ...... 62
4.1 Introduction ...... 62
4.2 Materials and Methods ...... 65
4.2.1 Description of the study site ...... 65
4.2.2 Experimental layout and data collection...... 65
4.3 Results and discussion...... 69
4.3.1 P. incana density and height distribution in two different treatments...... 69
vii
4.3.2 Species composition in Nyaniso communal rangeland...... 70
4.3.3 Effects of treatments on species composition of selected grass species...... 74
4.3.4. Effects of treatments on grass heights...... 75
4.3.5 Effects of treatments on grass diameter...... 77
4.3.6 Effects of treatment on grass yield...... 80
4.3.7. Effects of treatments on distance between tufts...... 81
4.3.8 Effects of treatments on soil minerals in Nyaniso communal area...... 83
4.3.9 Conclusion ...... 85
4.4 Recommendation...... 86
Chapter. 5 Summary ...... 87
5.1 General discussion ...... 87
5.2 Conclusion ...... 88
References ...... 90
viii
List of Appendices
APPENDIX 1 QUESTIONNAIRE...... 89
APPENDIX 2 ETHICAL CLEARANCE CERTIFICATE...... 98
APPENDIX 3 ANOVA TABLES...... 99
ix
List of tables
Table1. Percentage age distribution, educational and occupational status of the respondents in four villages (Respondents, n= 20)...... 30
Table 2.Percentage distribution of marital status and relation to house hold in percentage (n=20 per village)...... 31
Table 3. Livestock holdings (mean ±SE) in the four studied villages (n=20per village)...... 34
Table 4. Types of livestock raised by respondents in four villages (n=20 per village,
80=total)...... 35
Table 5. Relative importance (mean ranks) of the purposes for rearing livestock as ranked by the respondents (n= 20 per village)...... 38
Table 6. Attributing factors (mean rank) to livestock production as perceived by respondents...... 40
Table7. Mean ranks of perceived factors of rangeland degradation (respondents, n=
80)...... 42
Table 8. Mean ranks of rangeland uses starting from the most important to the list important across all the villages...... 44
Table.4.1 Mean shrub density across the treatments applied in Nyaniso rangeland...... 63
Table 4.2. Distribution of grass species (mean %) in four different treatments in Nyaniso communal rangelands...... 66
Table 4.3 Mean (± S.E) abundance of the common grass species in four treatments...... 68
Table4.4 Effects of treatments on grass heights (cm)...... 70
x
Table4.5 Effects of treatments on grass diameter (cm)...... 72
Table 4.6 Mean treatment effects on grass biomass production during summer and winter season in kg/ ha...... 74
Table 4.7 Treatments means on distance between tufts (cm)...... 75
Table 4.8 Soil properties between treatments in the rangeland of Nyaniso community...... 78
xi
List of Figures Figure 1. Mean ranks of livestock importance from the most important (3) to the least important (1)...... 36
Figure 2. Layout of the trial plots. Dotted lines demarcate the edge of the unfenced/open plot or subplot and solid lines show fenced and rested plots/subplot……………………………………………………………………..………….. 64
xii
List of abbreviations ANOVA Analysis of variance
Ca Calcium
Cu Copper
GLM General Linear Model
K Potassium
Mg Magnesium
N Nitrogen
P Phosphorus
Na Sodium
OC Organic Carbon
S.E Standard Error
SAS Statistical Analysis System
SPSS Statistical Package for Social Sciences
Zn Zinc
xiii
Chapter 1. Introduction
1.1Background
Shrub invasion refers to capability of a species to successfully invade communities, where it was previously not existing (Prieur-Richard and Lavorel, 2000). Shrub invaded landscapes normally have less herbaceous vegetation cover and more bare soils (Tighe et al., 2009). Shrub invasion is becoming a serious problem in large areas of South African rangeland to such an extent that previously economic livestock farming areas are no longer economically viable
(Smit, 2004). Invaded areas are prone to increased rain drop impact and reduced infiltration leading to increased run–off and severe soil erosion (Stringham, 2008). Invasion by unpalatable shrubs leads to food insecurity in the communal areas indirectly since the grazing lands become less productive and unable to support livestock production. Shrub invasion may have impacts on the rangeland ecosystem because invasive species result in excessive use of surface water resources and therefore reduction of stream water flow, disruption of ecosystem processes and structure, and a threat to diversity (Hoffman et al., 1999).
Studies conducted in parts of the Eastern Cape by Palmer and Avis (1994) and Kakembo
(1997) recognized P. incana (Blue bush), an unpalatable shrub dwarf bush, as one of the most widespread invader species. Grazing is reported by Prieur-richard and Lavorel (2000) as a major disturbance which favors invasion of the rangeland by these species. Davis and Pelsor
(2001) recognized that variations in resource availability between landscape positions starting from few weeks up to one year may have a great influence on plant invasion success.
Disturbance and water were recognized as the main factors that affected resource availability
(Davis and Pelsor, 2001).
1
Livestock production is a foundation for rural peoples’ livelihood and is dependent on the rangelands for forage production. However, these rangelands of South Africa and their surrounding homesteads occupy about 13% of agricultural land surface whereas 4.8% was identified as degraded land with 12.7 million people residing in these areas (Bennett and
Barrett, 2007; Bennett et al., 2012).
Furthermore, livestock reproduction rate is lower than the growth rate of human population.
The rangelands in this land tenure system have unrestricted access (Dreber et al, 2011;
Coronado-Quintana & McClaren, 2001; Benett & Barrett, 2007; Echavarria-Chairez et al,
2010), due to communal property ownership (CPO) with poor management regulations.
These threats correlate with ascending human population and increase in shrub density calling for increase in livestock numbers (Vetter et al, 2006) and other tragic anthropogenic uses of range resources.
Overstocking animals per unit area worsens the decline in general condition of the rangeland
(Kioko and Okello, 2010) and also sets up conditions for range degradation (Bakoglu et al,
2009; Smet and Ward, 2006; Muller et al, 2007). These high stocking rates are perpetuated by keeping more animals for various purposes such as to generate income, milk production, drought power, slaughter, bride price (Smet and Ward, 2006), wealth and status (Vetter et al,
2006).
Communal farmer’s perceptions (CFPs) can be used in tandem with the ecological methods of evaluating changes in rangelands (Angasa & Oba, 2007). CFPs can also aid in finding data of the local situations in focus to range degradation, thus adding value to scientific research
(Angasa & Oba, 2007; Kgosigoma et al, 2012). Research involving the knowledge of communal farmers may also enhance gaining information in connection with sustainable use,
2 development and protection of natural resources. The CFPs should be incorporated with scientific knowledge when the plan and decision making is to be done.
1.2 Problem statement Invasion of grazing lands by P. incana has been a problem in the communal rangelands of
South Africa. P. incana is assumed to be more competitive in terms of sunlight, water and soil nutrients than any other grass species growing beneath the canopies and in sub-canopy habitats.
Also this species may have allelopathic effects and result in decreased forage production and consequently livestock production.
Invasion of this species may threaten livestock production, food security and livelihoods of the communal people who depend on rangeland resources for food production. However, not many studies have been conducted to investigate the control methods of P. incana invasion or possible solution to minimize the further degradation of the rangeland ecosystem and increase the growth and production of more palatable grasses and forbs as feed for animals and improve the livelihoods of farmers.
1.3 Justification This study seeks to provide information on grass biomass production and soil chemical characteristics that are influenced by P. incana invasion and the harmful consequences of the invasion on rangeland productivity. Understanding the environmental conditions is critical for the management and control of P. incana. Extensive areas of grazing land have been invaded by P. incana and the measurement of the impact of P. incana on grazing capacity was of great interest so as to quantity its significance to minimize the invasion. This will also help to find ways of eradicating this invasion so as to provide more grazing veld for communal livestock such as cattle and goats which can be used to help improve the socio-economic standards of rural inhabitants.
3
1.4 Objectives General objective: The aim of the study was to assess the impact of P. incana invasion on rangeland production and people’s livelihoods.
Specific objective 1. To assess the farmers’ knowledge and perceptions of P. incana invasion and impacts on
rangeland, livestock production and livelihood in four communal areas.
2. To investigate the effects of Pteronia incana invasion on grass biomass production and species
distribution and soil chemical characteristics under systematic control methods.
4
Chapter 2 Literature review
2. 1 Introduction Invasive plant species are those species that can persist, reproduce, spread unassisted and sometimes at rapid rates across different landscapes. Invasive plants have harmful effects on indigenous plant species with significant management complications (Richardson, 1998).
Woody plant invasion into grasslands and rangelands are well documented globally (Briggs et al., 2005). One of the invasive species that is spreading profusely on parts of South African grasslands is Pteronia incana. The species is distributed from the Eastern Cape westwards to
Namaqualand (Goldblatt and Manning, 2000).
Since a few years ago, P. incana has been increasing in density on extensive rangelands of the
Eastern Cape. P. incana is indigenous to Nama Karroo regions of South Africa, successfully invading thicket and natural grassland (Kakembo et al., 2006). P. incana is a perennial woody shrub belonging to the Asteraceae family. The grey-leaved shrub has small, thin and white- woolly leafs. The yellow flower heads are discoid in shape and are solitary on branch tips and their flowering time is mainly during September to October.
Shrub invasion is widely recognized as one of the major threats to biodiversity and ecosystem stability (Mack et al., 2000) and therefore attracts attention from ecologists. There is a concern that the invasion may include less obvious changes below ground, that is, the soil and these detriments may in turn have impacts on invisibility of the ecosystem and the invasiveness of species (Ehrenfeld and Scott, 2001). Invaded rangelands and landscape have limited herbaceous vegetation cover and many bare patches (Tighe et al., 2009). Consequently, the grazing capacity of the communally owned grazing lands is also affected. factors of shrub invasion, land gradient and soil related factors, climate related factors, grazing as a factor of shrub invasion, fire as an influence of invasion, effects of shrub invasion on livestock production, effects shrub invasion on vegetation, effects on soil water, effects of shrub invasion
5 on people’s livelihoods, extent of shrub invasion in South Africa and effects of shrub invasion on land degradation are the areas of concerns for the following literature.
2.2 Causes of P. incana invasion
The causes of shrub invasion are complex and specific to ecosystem type, but are associated with long term changes in grazing, soil disturbances, flooding, fire and deforestation as well as more recent climatic changes, traits of an invader, low palatability, tolerances, predation, mutualism and competition (Kakembo, 2004; Briggs et al., 2005). P. incana invasion increases with soil moisture shortages. The abandonment of cultivated lands, climate change, over grazing and disruption of natural fire regimes have been frequently cited as possible causes in some invaded areas (Kakembo, 2003).
2.2.1 Landscape and soil related factors
According to Kakembo (2004) abandoned crop fields are the main P. incana invasion hotspots even though the main determinants are steep and south facing slope Ngqushwa district, Eastern
Cape. Soil nutrient content and physical properties are regarded as important factors encouraging shrub invasion (Tilman, 1997). Invasions are associated with high carbon dioxide levels in soil pores and high nitrogen levels in the soils invaded (Liao et al., 2008). Landscape organization and arrangement have a great effect on shrub invasion of rangelands (Vila and lbanez, 2011) by disturbance levels on the land and vegetation and its recognized effects on propagule pressure. According to Parker et al. (999), invasion is usually caused by anthropogenic disturbance of the soil, (Mack et al., 2000) as a result most studies on invasion have involved disturbed invasion systems. Invasive plants are regular and abundant in areas that have a history of strong and constant land use changes (Vila et al., 2003). Soils that have low nitrogen content and under humid areas and with leguminous trees and shrubs can have a
6 great competitive advantage over grasses more especially on bare areas that are due to disturbances (Ward, 2005; Higgins et al., 2003). Landscape formation has been reported to be the cause of shrub invasion hence densities are high in low lands, mountains and along river systems (Lesoli et al., 2013). One other impact of shrub invasion have included steep declines in plant species abundance (Baez and Collins, 2008), elevated risk of animal species extinction
(Spottiswood et al., 2009), reduced grazing capacity and many rangelands are no longer viable in terms of livestock production. The destruction caused by invasive plants to native plant communities and biodiversity in natural ecosystem is so extensive that these invaders are described to be the second most important cause of natural habitat degradation in North
America (With, 2001).
2.2.2 Climate related factors. Bush encroachment and shrub invasion like P. incana has been identified to be triggered by grazing impacts together with climate change (Ward, 2000; Kakembo, 2003 Angassa, 2012).
Increased atmospheric carbon dioxide concentration is reported as one of the causes of shrub invasion and bush encroachment that had been justified to be due to different pathways of photosynthesis that usually respond in a different way to carbon dioxide accumulation changes
(Higgins et al., 2003).
Disturbance such as increased fire frequency or nitrogen deposition together with precipitation has been suggested to favour shrub invasion (Walther et al., 2002; Field et al., 2007). Shrub invasion is due to environmental factors such as inter annual rainfall variability and exclusion of browsers (De Klerk, 2004). The occurrence of severe storms can provide a role of invaders to spread and invade in the places where they were previously unavailable (Sax and Brown,
2000). Environmental fluctuations, specifically precipitation and temperature regimes, also influence grass-shrub dynamics (D’Odorico et al., 2010) such as high rainfall areas are associated with high woody density and some other grasses beneath tree canopies e.g. Panicum maximum.
7
2.2.3 Grazing as a factor of shrub invasion The combined effects of the previous land use and poor grazing management, (like overgrazing) is clearly stated to trigger P. incana invasion in the report of Kakembo (2007).
Grazing has been proved to be a crucial mechanism underlying plant-plant interactions in arid and semiarid environments, with changes from negative to positive relations under high grazing pressure (Graff et al., 2007 and Soliveres, et al., 2011). Shrub invasion is related to changes in grazing management (Sankaran et al., 2005). Therefore, increased grazing pressure normally results in reduction of grass biomass and flammable material associated with grasses which cause reduction in fire frequency and intensity (Scholes and Archer, 1997; Van Auken, 2009;
Lesoli, 2013) influencing grass shrub-coexistence. If the grass layer is over-utilized it loses its competitive edge against shrubs and bushes and that allows more water to percolate into the sub-soil, where it becomes available for shrubs (Wiegand et al., 2005).
Besides climate conditions and other factors, rabbit and hare browsing and grazing is one of the factors that contribute to shrub seedling survival and morphology (Cohn and Bradstock,
2000). In a study conducted in Mediterranean communities by Midgley (2003); it has been postulated that the seeders (plants that recruit post fire by only seeds) would increase with very high fire frequency although seeder can only persist in the community if they reach the sexual maturity before plants are killed by fire. After burning, seedling density of seeders is usually high and shrub seed distribution through dung defecation result to woody plant increase
(Ferrandis et al., 2001).
2.2.4 Fire as a factor of invasion
According to Lunt and Spooner (2005), different fire regimes may have caused wood lands to multiply the invasion of native shrubs. Disruption of natural fire regimes have been frequently cited as possible cause in some invaded areas (Kakembo, 2001). The exclusion of range fires in combination with lowermost lands cultivation and continuous grazing were reported to have
8 induced shrub invasion which have resulted to grass biomass reduction and poor rangeland condition (Oba et al., 2000; Gifford and Howden, 2001).
2.3 Effects of shrub invasion 2.3.1 Effects of shrub invasion on livestock production Invading plant species affect production of livestock in agriculture through decrease of forage quality and yield, interfering with poisoning in animals increasing management and production costs of livestock and eventually land value increases (Di Tomaso, 2000). However, woody plant invasion decreases the ecosystem carrying capacity as a bigger portion of the land is mountainous in South Africa, not used and busy with Agricultural production and this result to high stocking rate per unit area. High stocking rate per unit area results in low animal production returns. This has severe outcomes for food security and income generation to farmers (Ward, 2005). The amount of invasion has a great effect on how well the prey may see a predator and escape it, as a result jackals and other preys have a significant effect on small stock loses due to their predation which is highly promoted by hiding in invaded areas. (Kunkel and Pletscher, 2000) and (Creel and Winnie, 2005).
Besides suppression of herbaceous forage by invading species, dense bush in rangelands reduces ease of access to land by livestock and that reduces the chances of range utilization
(Lesoli, 2013). According to Jacobs (2000), invading species tend to have very high levels of phenolic compounds (e.g. tannins) in their leaves, which reduce their digestibility by livestock and wildlife.
2.3.2 Effects of shrub invasion on vegetation
Plant invasion alters the grassland micro environment, like Juniperus virginiana expansion into grasslands and decreases herbaceous species diversity in a study conducted in Brazil
(Linneman and Palmer, 2006); changes soil hydrological properties and nutrient cycles (Bekele
9 et al., 2006) and alters ecosystem water balance (Axmann and Knapp, 1993). The establishment of an invasive plant species in an area can decrease plant diversity (Theoharides and Dukes,
2007), inhibit forest regeneration, decrease agricultural production, change structure and function of communities and ecosystems, change population genetics, and community compositions of an area and generally alter ecosystem properties (Vitousek,1990). Increase in density of woody plants has negative effects on herbage biomass production according to (Oba and Kolite, 2001; Van Auken, 2009).
2.3.3 Effects of shrub invasion on soil water Several studies reported that woody plant invasion decreases stream flow in the semi-arid rangelands (Tennesen, 2008). P. incana is highly competitive to grass production in terms of soil water and that continually results in permanent wilting point in grasses next to it
(Kakembo, 2009). Consequently, shrub invaded areas often suffer from reduced ground water recharge, to such an extent that for many smaller towns, it results in water scarcity where additional boreholes are needed where as it would be cheaper to debush than to drill new boreholes (Christian, 2010). Shrub invasion usually results in changes in nutrient circulation due to sudden changes in ground water flow eventually results in imbalance of soil nutrients
(Eppinga et al., 2009; Troxler and Childers, 2010). Some other tree species lose more water during evapotranspiration and that result in low water availability to grasses under the canopies leading to their permanent wilting (Limpens et al., 2011). At some point shrub-grass coexistence results to decrease in evapotranspiration in grass vegetation and improves the moisture content of the soil due to shrub canopy shade (Zeng et al., 2004; D’Odorico et al.,
2007; Wang et al., 2009). Consequently, stands of alien trees and shrubs in the rangelands can rapidly reduce abundance and diversity of native plants due to low water availability
(Richardson et al., 2000).
10
2.3.4 Effects of shrub invasion on people’s livelihoods Shrub invasion and woody multiplication on the natural grazing lands has been observed as the greatest threat of rangeland degradation by numerous pastorals in Africa (Solomon et al., 2007;
Angassa and Oba 2008). In a study conducted in the Eastern Cape by Solomon et al. (2014)
Eryops floribundus invasion was reported to be the greatest agricultural and environmental challenge that threatens the available range assets as well as their livelihoods. The Eryops floribundus out-competes the vegetation beneath canopies as it is not grazed by livestock even under drought periods where feed is scarce (Solomon et al., 2014). However, the above mentioned phenomenon resulted in range degradation that indirectly affects livestock production and that eventually affects farmers’ livelihoods. As a result of the shrub invasion and degradation, people turn to leave the rural life to the urban life to seek other livelihood alternatives (Berry et al., 2003; Solomon et al., 2014). Shrub invasion is reported to affect livestock population and sales as most farmers raise their livestock for income purposes, therefore this problem also affects the social life of the farmers due to low profits (Kassahun et al., 2008).
2.4 Effects or role of shrub invasion on land degradation Shrub invasion of grassy savanna and grassland is observed as an important threat worldwide
(Van Auken, 2000) and (Watkinson and Ormerod, 2001). Vast areas of land in Mgwalana community, Eastern Cape South Africa are subject to gully erosion due to P. incana invasion
(Kakembo, 2004). Shrubs mostly survive on the arid and semi-arid areas and some of them have greater drought as well as wind erosion resistance (Facelli and Temby, 2000). Therefore invasion has been regarded as one of the conditions of the dry land degradation with the most noticeable driving force identified as prolonged, elevated levels of herbivory by domestic animals (Scholes, 2009; Van Auken, 2000).
11
2.5 Extent of shrub invasion in South Africa South Africa’s natural ecosystems such as rangelands are under threat from invasive alien plants (Ward, 2005). About 10 million hectors of land (i.e. 8 percent of the country’s total area) has been invaded by shrubs (Maitre et al., 2009; Nyoka, 2003). Of the total of 8750 species recorded in Africa, 161 are regarded as invasive species, of which 68% are woody species
(Nyoka, 2003).
Acacia mearnsii is currently considered to be the most invasive tree species in South Africa; it has invaded more than 2.5 million hectors land space, mostly riparian areas, rangelands and forest (Galatowitsch and Richardson, 2004).
Surveys conducted in parts of the Eastern Cape, South Africa by Palmer and Avis (1994) and
Kakembo (1997) recognized P. incana, an unpalatable Karroid dwarf bush, to be one of the widespread invader species. The shrub was detected as spreading rapidly from stream valley bottoms onto many grazing lands and abandoned cultivation fields. Steep slopes are reported to be the one of the influences determining shrub invasion, hence mountains are the invasion hotspots, steep areas and river banks more especially in Ngqushwa district (Richardson et al.,
1997).
The vegetation type determines the vulnerability of the rangeland to degradation and shrub invasion as a result there is high invasion in grassland and savanna biomes mostly by scramblers (triffid weed, Chromolaena odorata and Rubus species (Lesoli, 2013). As far as the biomes of South Africa are concerned, the Fynbos (a Mediterranean-type shrub land) is the most invaded biome by shrubs and woody species in South Africa (DWF, 1997). Fynbos biome encompasses 80 % of the Cape floral kingdom of the southern-western and Cape of South
Africa, includes three vegetation types of which shrubs the so called Fynbos which are the most dominant ones (Lee and Crous, 2003).
12
Larger areas of alluvial plains and seasonal and ephemeral water courses in the Nama karroo have been invaded by notably mesquite (Prosopis species). Nama karoo is an arid to semi-arid region in the central to western parts of South Africa (Visser et al., 2003).In the province of the Eastern Cape species like Atriplex and Opuntia Species are found in high densities specifically in this Nama Karoo as well as succulent Karroo and thicket biome (Richardson et al., 1997).
2.6 Perceptions of communal farmers on the situation of shrub invasion
Most communal farmers can identify invasive and non-invasive species that threaten their rangeland production (Angassa and Oba, 2008). Communal farmers are knowledgeable with regards to rangeland management (Ngulube, 2003) and therefore, it is useful to consider their ecological knowledge regarding livestock development, rangeland management strategies and planning programmes. Communal farmers spend a lot of their time on rangelands and they could share their ecological knowledge with the researchers. In so doing they could provide long term ecological viewpoint of bush encroachment or vegetation changes and the primary causes which is lacking in previous studies (Roba and Oba, 2009). There is an observation that communal farmers are known to have a significant knowledge of vegetation trends, species abundance and acceptability to grazing animals (Davis, 2005). They are also very knowledgeable about factors that impact vegetation change such as rainfall availability, fire and grazing pressure (Oba and Kaitira, 2006). Consequently it is very fundamental to understand how communal farmers perceive rangeland conditions and the extent of bush encroachment in communal areas.
Communal farmers are knowledgeable about the degree and time frames of deterioration of their rangelands (Ngulube, 2003). Rangeland deterioration includes bush encroachment, shifts in species composition and the reduction of forage production. Bush encroachment has been
13 observed by communal farmers to be the major problem that deteriorates the condition of rangelands. In a study conducted by Angassa and Oba (2008) communal farmers noticed the decline of forage production and change in species composition and correctly attributed it to the rapid increase of woody plants (bush encroachment). Results of another study indicated that communal farmers perceived that some encroaching woody species have the tendency of suppressing growth of palatable herbaceous plants and creating conditions for the growth of unpalatable ones.
The communal farmers are also capable of identifying invasive and non-invasive species that threaten their rangelands (Angassa and Oba, 2008). Communal farmers are known to have rich indigenous knowledge with regards to rangeland management (Ngulube, 2003) and therefore, it is useful to consider their ecological knowledge regarding their livestock development, rangeland management strategies and planning programmes. Communal farmers interact with their rangelands and they could share their ecological knowledge with the researchers. In so doing they could provide long term ecological viewpoint of bush encroachment or vegetation changes and the primary causes which is lacking in previous studies (Bart, 2006; Roba and
Oba, 2009). Davis (2005) stated that communal farmers are known to have very useful knowledge of vegetation trends, species richness and acceptability to grazing animals. They are also very knowledgeable about factors that influence vegetation change such as rainfall availability, fire and grazing pressure (Oba and Kaitira, 2006). Therefore it is very crucial to understand how communal farmers perceive rangeland conditions and the extent of bush encroachment in communal areas.
14
2.7. Summary
South African livestock and wildlife is largely supported under savanna rangeland production for their assigned requirement to be met. However shrub invasion has been noticed to be in wide range in communal natural grazing lands. Shrub invasion has been associated with grass suppression and that affect livestock, wild life production and ecosystem services and humanity at large. Besides suppression of grasses by invasive species, high shrub density in rangeland prohibits the accessibility of land by livestock. In the communal areas livestock production extensively rely mainly on rangelands for nutrition. Therefore indigenous knowledge of the rural communities is worthwhile regarding rangeland status and livestock management practices. Farmers must also be aware of the effects of P. incana on the ecosystem and the control methods of P. incana shrub so as to minimize its effects in agriculture.
15
References Angassa, A., and Oba, G., 2008. Herder perceptions on impact of range enclosures, crop
farming, fire ban and bush encroachment on the rangelands of Borana, southern
Ethiopia. Human Ecology, 36: 201–215.
Angassa, A., Oba, G., and Tolera, A., 2012. Bush encroachment control demonstrations and
management implications on herbaceous species in savannas of Southern Ethiopia.
Axmann, B.D., and Knapp, A., K.1993. Water relations of Juniperus virginiana and
Andropogon gerardii in an unburned tall grass Prairie watershed. The South Western.
Naturalist, 38: 325-330.
Ba´ez, S., and Collins, SL., 2008. Shrub Invasion Decreases Diversity and Alters Community
Stability in Northern Chihuahuan Desert Plant Communities. PLoS ONE 3: e2332.
doi:10.1371/journal.pone.0002332.
Bakoglu, A., Bagci, E., Erkovan, H.I., Koc, A., and Kocak, A., 2009. Seed stocks of grazed
and ungrazed rangelands on Palandoken Mountains of Eastern Anatolia. Journal of
Food, Agriculture & Environment, 7: 674 – 678.
Bart, D., 2006. Integrating local ecological knowledge and manipulative experiments to find
the causes of environmental change. Frontiers in Ecology and the Environment 4: 541-
546.
Benett, J., and Barrett, H., 2007. Rangeland as a common property resource: Contrasting
insights from Communal areas of Central Eastern Cape Province, South Africa. Human
Ecology, 35: 97 – 112.
16
Bennet, J.E., Palmer, A.R., and Blackett, M.A., 2012. Range degradation and land tenure
change: Insights from ‘Relaesed’ communal area of the Eastern Cape Province, South
Africa. Land Degradation and Development, 23: 557 – 568.
Berry, L., Olson, J., and Campbell, D., 2003. Assessing the Extent, Cost and Impact of Land
Degradation at the National Level: Findings and Lessons Learned from Seven Pilot
Case Studies. World Bank Report, USA: World Bank.
Beyene, S.T., Mlisa, L., and Gxasheka, M., 2014. Local Perceptions of Livestock Husbandry
and Rangeland Degradation in the Highlands of South Africa: Implication for
Development Interventions. Journal of Human Ecology, 47: 257-268.
Briggs, JM., Knapp Ak., Blair JM., Heisler JL., Hoch GA., Lett MS., and McCarron, K., 2005.
An ecosystem in transition: woody plant expansion into mesic grassland. BioScience,
55: 243-254.
Christian, C., 2010. Energy for the Furture: Bush-to-fuel Project. Environmental Impact
Assessment Report (Unpublished Environmental Impact Assessment Report for Energy
for the Future (Pty) Ltd No. C026). Windhoek.
Cohn, J.S., and Bradstock, R.A., 2000. Factors affecting post fire seedling establishment of
selected mallee understory species. Journal of Botany, 48: 59–70.
Coronado-Quintana, J.A., and McClaren, M.P., 2001. Range condition, Tenure, Management
and Bio-physical Relationships in Sonora, Mexico. Journal of Range Management, 54:
31 – 38.
Creel, S., and Winnie, JR., 2005. Responses of elk herd size to fine scale spatial and temporal
variation in the risk of predation by wolves. Animal Behavior, 69: 1181-1189.
17
D’Odorico, P., Caylor, K., Okin, G.S., and Scanlon, T.M, 2007.On soil moisture-vegetation
feedbacks and their possible effects on the dynamics of dry land ecosystems. Journal
of Geophysical research, 112: 5-8.
Davis, D.K., 2005. Indigenous knowledge and the desertification debate: problematizing
expect knowledge in North Africa. Geoforum, 36: 509-524.
De Klerk, J.N., 2004. Bush encroachment in Namibia. Report on Phase1 of the bush
encroachment Research, Monitoring and Management Project, Ministry of
Environment and Tourism, Windhoek.
DiTomaso, J.M., 2000. Invasive weeds in rangelands: species, impacts, and management.
Weed Science, 48: 255-265.
D'Odorico, P., Fuentes, J.D., Pockman,W.T., Collins, S.L., He,Y., Medeiros, J.S., DeWekker,
S., and Litvak, M.E., 2010. Positive feedback between microclimate and shrub
encroachment in the northern Chihuahuan desert Ecosphere, 1–11.
D'Odorico, P., Laio, F., and Ridolfi, L., 2010, Does globalization of water reduce societal
resilience to drought? Geophysical Research letters. An AGU Journal, 37: 47.
Dreber, N., and Esler, K.J., 2011. Spatio-temporal variation in soil seed banks under contrasting
grazing regimes following low and high seasonal rainfall in arid Namibia. Journal of
Arid Environments, 75: 174 – 184.
DWAF., 1997. The working for Water Programme: Annual report., 1997. Department of
Water Affairs and Forestry, Pretoria.
Echavarria-Chairez, F.G., Serna-Perrez, A., Salinas-Gonzalez, H., Iniguez, L., Palacios-Diaz.,
M.P., 2010. Small ruminant impacts on rangelands of semi-arid highlands of Mexico
and the reconverting by grazing systems. Small ruminant research, 89: 211 – 217.
18
Ehrenfeld, J.G., and Scott, N., 2001. Invasive species and the soil: effects on organisms and
ecosystem processes. Ecology Application, 11: 1259-1260.
Eppinga, M.B., de Ruiter, P.C., Wassen, M.J., and Rietkerk, M., 2009. Nutrients and hydrology
indicate the driving mechanism of peatland surface patterning. American Naturalist,
173: 803–818.
Facelli, J.M., and Temby, A.M., 2000. Multiple effects of shrubs on annual communities in
arid lands of South Australia. Aust. Ecol. 27: 422-431.
Ferrandis, P., de las Heras, J., Martínez Sanchez, J.J., and Herranz, J.M., 2001. Influence of a
low-intensity fire on a Pinus halepensis Mill. Forest seed bank and its consequences on
early stages of plant succession. Israel Journal of Plant Sciences, 49: 105-114.
Field, C.B., Mortsch, L.D., and Brklacich, M., 2007. North America. In climate change:
Impacts, Adaptation and Vulnerability. Contribution of Working group II to the fourth
Assessment Report of the intergovernmental panel on climate change (eds Parry ML,
Canziani of Palutik of Jp, Van Der Linden PJ, Hanson CE), Cambridge University
Press, Cambridge, Uk.
Galotowitsh, S., and Richardson, D.M., 2004. Riparian Scrub Recovery After Clearing of
Invasive Alien Trees in headwater Streams of the Western Cape, South Africa.
Biological Conservation, 12: 509-521.
Gifford, R.M., and Howden, M., 2001. Vegetation thickening in an ecological perspective:
significance to national greenhouse gas inventories. Environmental Science and Policy,
4: 59-72.
19
Goldblatt, P., and Manning, J.C., 2000. Cape plants: A Conspectus of the Cape flora of
Southern Africa. National Botanical Institute, Cape Town and Missouri Botanical
Garden, St Louis.
Graff, P., Aguiar, M.R., and Chaneton, E.J., 2007. Shifts in positive and negative plant
interactions along a grazing intensity gradient. Ecology, 88: 188–199.
Higgins, S I., Bond, W J., Trollope, W., and Fire, W., 2003. Resprouting and variability: A
recipe for grass-tree coexistence in savanna. Journal of Ecology, 88: 213-229.
Hoffman, MT., Toodd, S., Ntshona, Z., and Turner, S., 1999. Land degradation in South Africa.
Final report to the department of Environmental Affairs and Tourism, South Africa.
Jacobs, N., 2000. Grasslands and Thickets: Bush encroachment and Herding in the Kalahari
Thornveld. Environment and History, 6: 289-316.
Kakembo, V., 1997. A reconstruction of the history of land degradation in relation to land use
change and land tenure in Peddie District, former Ciskei, MSc thesis, Rhodes
university, Grahams town.
Kakembo, V., 2001. Trends in vegetation degradation in relation to Tenure, Rainfall, and
population changes in Peddie District, Eastern Cape, South Africa Environmental
Management, 28: 39-46.
Kakembo, V., 2004. Factors affecting the invasion of Pteronia incana (Blue bush) onto
hillslope in Ngqushwa (formerly Peddie) District, Eastern Cape, PhD thesis, Rhodes
University, Grahamstown.
Kakembo, V., 2009. Vegetation patchiness and implications for landscape function: The case
of Pteronia incana invader species in Ngqushwa Rural Municipality, Eastern Cape,
South Africa. Catena, 77: 180-186.
20
Kakembo, V., Palmer, AR., Rowntree, K., 2006. The use of high resolution digital imagery to
characterize the distribution of Pteronia incana invasive species in Ngqushwa
(formerly Peddie) District, Eastern Cape, South Africa. International Journal of Remote
Sensing, 27: 2735-2752.
Kakembo, V., Rowntree, K.M., and Palmer, A.R., 2007. Topographic controls on the invasion
of Pteronia incana (Blue bush) onto hill-slopes in Ngqushwa (formerly Peddie)
District, Eastern Cape. Catena, 70: 185–199.
Kassahun, A., Snyman, HA., and Smit, G., 2008. Impacts of rangeland degradation on the
pastoral production systems. Livelihoods and perceptions of the Somali pastoralists in
Eastern Ethiopia. Journal of Arid Environment, 72: 1265–1281.
Kgosikoma, O., Mojeremane, W., and Harvie, B., 2012. Pastoralists’ Perception and
Ecological Knowledge on Savanna Ecosystem Dynamics in Semi-arid Botswana.
Ecology and Society, 17: 27 – 38.
Kioko, J., and Okello, M.M., 2010. Land use cover and environmental changes in semi-arid
rangeland, Southern Kenya. Journal of Geography and Regional Planning, 3: 322 –
326.
Kunkel, K.E., and Pletscher, D.H., 2000. Wildlife Biology Program, School of Forestry,
University of Montana, Missoula, MT 59812, U.S.A.
Lee, S., and Crous, PW., 2003. Taxonomy and biodiversity of Hyysteriaceous ascomycetes in
fynbos. South African journal of Botany, 69: 480-488.
Lesoli, M.S., Gxasheka, M., Solomon, T.B., and Moyo, B., 2013. Integrated plant Invasion and
Bush encroachment Management on Southern African Rangelands. In: Herbicides
current Research and case studies in use. Andrew, J. and Jessica A. Kelton.
21
Liao, CZ., Peng, RH., and Luo, YQ., 2008 Altered ecosystem carbon and nitrogen cycles by
plant invasion: an analysis. New Phytologist, 177: 706-714.
Limpens, J., Granath, G., Gunnarsson, U., Aerts, R., Bayley, S., Bragazza, L., Bubier, J.,
Buttler, A., van den Berg, LJL., and Francez, AJ, 2011. Climatic modifiers of the
response to nitrogen deposition in peat-forming Sphagnum mosses: a meta-analysis.
New Phytologist, 191: 469–507.
Linneman, JS., and Palmer, M.W., 2006. The effect of Juniperus virginiana on plant species
composition in an Oklahoma grassland. Community Ecology, 7: 235- 244.
Lunt, I.D., and Spooner, P.G., 2005. Using historical ecology to understand patterns of
biodiversity in fragmented agricultural landscapes. Journal of Biogeography, 32: 1859–
1873.
Mack, R.N., Simberloff, D., and Lonsdale, W.M., 2000. Biotic invasion: causes, epidemiology,
global, consequences, and control. Ecological Applications, 10: 689-711.
Maestre, F.T., Bowker, M.A., Puche, M. D., Hinojosa, M. B., Martinez, I., Garcia- Palacios, P.,
Castillo, A. P., Soliveres, S., Luzuriaga, A.L., Sanchez, A. M., Carreira, J.A., Gallardo, A.,
and Escudero, A., 2009. Shrub encroachment can reverse desertification in semiarid
Midgley, J.J., 2003. Is bigger better in plants? Hydraulic costs of increasing plant height.
Trends in Ecology and Evolution, 18: 5-6.
Muller, B., Frank, K., and Wissel, C., 2007. Relevance of rest periods in non-equilibrium
rangeland system- A modelling analysis. Agricultural Systems, 92: 295 – 317.
Ngulube, P., 2003. Using the SECI knowledge management model and other tools to
communicate and manage tacit indigenous knowledge. Innovation, 29: 21-30.
Nyoka, B.I., 2003. Biosecurity in forestry: A case study on status of invasive forest trees
species in Southern Africa. Forest Biosecurity Working Paper FBS/1E. Forestry
Department. FAO, Rome.
22
O’Farrelell, P.J., Danaldson, J.S., and Hoffman, M.T., 2007. The influence of ecosystem goods
and services on livestock management practices on the Bokkeveld plateau, South
Africa. Agriculture, ecosystems and environment doi:101016. Agee. 2007.01.025.
Oba, G. and Kaitira, L.M. 2006. Herder knowledge of landscape assessments in arid rangelands
in Northern Tanzania. Journal of Arid Environments, 66: 168-186.
Oba, G., and Kotile, D.G., 2001. Assessments of landscape level degradation in Southern
Ethiopia: pastoralists versus ecologists. Land Degradation & Development, 12: 461-
475.
Oba, G., Post, E., Syvertsen, P.O., and Stenseth, N.C., 2000. Bush cover and range condition
assessments in relation to landscape and grazing in southern Ethiopia. Landscape
Ecology, 15: 535-546.
Palmer, A. R., and Avis, A.M., 1994. The description, mapping and evaluation of recent
changes in the contemporary vegetation patterns, Land and Agricultural Policy Centre,
Mid-Fish River zonal study, Rhodes University, Grahams town.
Parker, I.M., Simberloff, D., Lonsdale, W.M., Goodell, K., Wonham, M., and Karieva, P.M.,
1999. Impact: toward a framework for understanding the ecological effects of invaders.
BiolInvasions, 1: 3–19. doi:10.1023/A:1010034312781.
Prieur-Richard, A.H., and Lavorel, S., 2000. Invasions: the perspective of diverse plant
communities, Australia Ecology, 25: 1-7.
Richardson, D M., Macdonald, I., Hoffman, W., and Henderson, J H. L., 1997. Alien plant
invasions. In: Cowling R M., Richardson, D M., and Pierce, S M. (eds). Vegetation of
Southern Africa. Cambridge University Press, Cambridge, 535-570.
Richardson, D.M., 1998. Forestry Trees as invasive Aliens. Conservation Biology, 12: 18-26.
doi: 10.
23
Richardson, D.M., Pysek, P., Rejmanek, M., Barbour, M. G., Panetta, DF, and West, C.J., 2000.
Naturalization and invasion of alien plants: Concept and definitions. Diversity
Distribution, 6: 93-107.
Roba, H.G., and Oba, G., 2009. Community participatory landscape classification and
biodiversity assessment and monitoring of grazing lands in Northern Kenya. Journal of
Environmental Management, 90: 673-682.
Sankaran M, Hanan, N.P., Scholes, R.J., Ratnam, J., Augustine, D.J., Cade, B.S., Gignoux, J.,
Higgins, SI., Le Roux, X., Ludwig, F., Ardo, J., Banykwa, F., Bron,. A., Bucini, G.,
Caylor, K.K., Coughenour, M.B., Diouf, A., Ekaya, W., Freal, CJ., February, EC.,
Frost, PGH., Hiernaux, P., Hrabar, H., Metzege. K.L., Prins, HHT., Ringrose, S., Sea,
W., Tews, J., Worden, J., and Zambatis, N., 2005. Determinants of woody cover in
African savannas. Nature, 438: 846-849.
Sax, D.F., and Brown, J.H., 2000. The paradox of invasion, Global Ecology and Biogeography,
9: 363-371.
Scholes, R.J., 2009. Syndromes of dry land degradation in Southern African. African Journal
of Range and Forage Science, 26: 113-125.
Scholes, R.J., and Archer, S.R., 1997. Tree–grass interactions in savannas. Annual Review of
Ecology and Systematics, 28: 517–544.
Smet, M., and Ward, D., 2006. Soil quality gradients around water-points under different
management systems in a semi-arid savanna, South Africa. Journal of Arid
Environments, 64: 251 – 269.
24
Smit, G.N., 2004.An approach to tree thinning to structure Southern Africa savannas for long
term restoration from bush encroachment. Journal of Environmental management, 2:
179-191.
Soliveres, S., Eldridge, D.J., Maestre, F.T., Bowker, M.A., Tighe, M. and Escudero, A., 2011.
Microhabitat amelioration and reduced competition among understory plants as drivers
of facilitation across environmental gradients: Towards a unifying framework.
Perspectives in Plant Ecology, Evolution and Systematics.
2011http://dx.doi.org/10.1016/j.ppees. 2011.06.001.
Solomon, B.T., Mlisa, L., and Gxasheka, M., 2014. Euryops Floribundus Encroachment in
Eastern Cape communal Rangelands: Indigenous and Scientific Understanding of
Effects on Range Ecology, and Food security and climate. Msc Dissertation, South
Africa: University of Fort hare.
Solomon,T.B., Snyman, H.A., and Smit, G.N., 2007. Cattle management practices and
perceptions of pastoralists towards rangeland degradation in Borana zone of Southern
Ethiopia. Journal of Environmental Management, 82: 481–494.
Spottiswoode, C.N.,Wondafrash, M., Gabremichael, M.N., Dellelegn,Y., Mwangi, M.K.,
Collar, N. J., and Dolman, P. M., 2009. Rangeland degradation is poised to cause
Africa’s First recorded avian extinction. Anim. Cons. 12: 249‐257.
Stringham, E.P., 2008. “Privatizing the Adjudication of Disputes” Paper presented at Research
Institute of Industrial Economics Conference, Vaxholm, Sweden, June, 17: 2008.
Tennesen, M., 2008.When juniper and woody plants invade, Water May Retreat. Sci. 322:
1630-1931.
25
Theoharides, K.A., J.S., and Dukes, 2007. Plant invasion across space and time: factors
affecting non indigenous species success during four stages of invasion. New
Phytologist, 176: 256-273
Tighe, E., Livert, D., Barnett, D., and Saxe, L., 2009. Cross-survey analysis to estimate low
incidence religious groups. Waltham: Brandeis University. Steinhardt Social research
institute.
Tilman, D., 1997. Community invisibility, recruitment limitation and grassland biodiversity.
Ecology, 78: 81-92.
Troxler, T.G., and Childers, D.L., 2010. Biogeochemical contributions of tree islands to
everglades wetland landscape nitrogen cycling during seasonal inundation.
Ecosystems, 13: 75–89.
Van Auken, O.W., 2000. Shrub invasion of North American semiarid grasslands. Annual
Review of Ecology and Systematics, 31: 197-215.
Van Auken, O.W., 2009. Causes and consequences of woody plant encroachment into western
North American grassland. Journal of Environmental Management, 9: 2931-2942.
Vetter, S., Goqwana, W.M., Bond, W.J., and Trollope, W.S.W., 2006. Effects of land tenure,
geology and topography on vegetation and soils of two grassland types in South Africa.
African Journal of Range and Forage Science, 23: 13 – 27.
Vilà, M., and Ibá˜nez, I., 2011. Plant invasions in the landscape. Landscape Ecology, 26: 461–
472.
26
Vilà, M., Burriel, J. A., Pino, J., Chamizo, J., Llach, E., and Porterias, M., 2003. Association
between Opuntia species invasion and changes in land-cover in the Mediterranean
region. Global Change Biology, 9: 1234–1239.
Visser, N., Botha, J.C., and Hardy, M.B., 2003. Re-establishing vegetation on bare patches in
the Nama Karoo, South Africa. Journal of Arid environments, 57: 15-37.
Vitousek, P.M., 1990. Biological invasion and ecosystem processes: towards an integration of
population biology and ecosystem studies. Oikos, 57: 7-13.
Walther, G.R., Post, E., Convey, P., Menzel, A., Parmesan, C., Beebee, T.J., Fromentin, J.M.,
Hoegh-Guldberg, O, and Bairlein, F., 2002. Ecological responses to recent climate
change. International weekly journal of science. Nature, 416: 389-395.
Wang, L., D’Odorico, P., Manzoni, S., Proporato, A., and Macko, S., 2009. Soil carbon and
nitrogen dynamics in southern African savannas: The effect of vegetation-induced
patch-scale heterogeneities and large scale rainfall gradients. Climate Change, 94: 63–
76.
Ward, D., 2005. Do we understand the causes of bush encroachment in African savannas?
African Journal of Range and Forage Science, 22: 101-105.
Ward, D., Ngairorue, B.T., Karamata, J., Kapofi, I., Samuels, R.and Ofran, Y., 2000. Effects
of communal pastoralism on vegetation and soil in a semi-arid and in an arid region of
Namibia. In: White P S, Mucina L, Leps J and Van Der Maarel E (Eds) Vegetation
Science in Retrospect and Perspective. Opulus Press, Uppsala, Sweden, 344-347.
Watkinson, A.R., and Ormerod, S.J., 2001. Grasslands, grazing and biodiversity: editors’
introduction. Journal of Applied Ecology, 38: 233-237.
27
Wiegand, K., Salt, D., and Ward, D., 2005. A patch-dynamics approach to savanna dynamics
and woody plant encroachment-Insight from an arid savanna. Perspectives in plant-
ecology, Evolution and systematics, 7: 229-242.
With, K., 2001. The landscape ecology of Invasive Spread in Conservation Biology, 16: 5.
Zeng, X., Shen, S.S.P., Zeng, X., and Dickinson, R.E., 2004. Multiple equilibrium states and
the abrupt transitions in a dynamical system of soil water interacting with vegetation.
Geophysical Research Letters. doi:10.1029/2003GL018910, 2004.
28
Chapter 3: Assessment of farmer’s knowledge and perception of Pteronia incana invasion and its impacts on livelihoods in four communal areas of Ngqushwa, Eastern Cape.
Abstract
This study evaluated the communal farmer’s perceptions of the Pteronia incana invasion on the rangelands and livestock production. A total of 80 farmers were selected from four communal areas, namely Mgwalana, Celetyuma, Nyaniso and Nobumba. From each communal area, 20 households that own livestock were randomly selected to conduct an interview. From livestock species, goats had the highest mean household holding number in relation to sheep and cattle across the selected villages. Both goats and cattle had equal or more importance than sheep. Three out of four villages raised cattle primarily for income generation and secondarily for cultural purposes like slaughtering during weddings ceremonies, amazila and also during female circumcisions (Ntonjane). Similarly, goats and sheep are primarily raised for cash income generation. The respondents revealed that the livestock population decreased over the last one-two decades and poor rangeland condition is assumed to be the cause of the situation as feed is the key factor for production. The area was dominated by the grasses more than by woody species so the P. incana is more competitive over grasses than woody species as it increases in density.
It was concluded that Ngqushwa communal farmers were partially knowledgeable about the effects P. incana invasion and their livelihoods in agriculture. P. incana was indigenous to the study area and the density has increased significantly over the last 10-20 years. Climate change could be associated with the increase of the invasion. Forage and animal performance as well as farmers’ economic status (livelihoods) were negatively affected by P. incana invasion.
29
Key words: Invasive species, Farming, Poverty, Shrub invasion, Rangeland production.
3.2 Introduction. South African communal areas are inhabited largely by black people who are involved in the production of crops and livestock mainly for sale on local and informal markets, consumption and for other socio-cultural reasons. Invasive plant species are considered as one of the greatest threats to arable and grazing land. Invasion is regarded as one of the degradation examples that usually result in reduced productivity of the rangeland and inappropriate land use practices are associated with this problem (Hudak, 1999; van Auken, 2000). The economic costs of alien invasive species worldwide were estimated to be US$ 1.4 trillion per year (Pimental et al.,
2000). More than 70% of communal farmers in South Africa rely on livestock for their livelihoods (Bester et al., 2003). The communal farmers depend on livestock for meat, milk, hides, manure, cash, drought power and social- cultural uses (Beyer et al., 2004). Indeed, the relative importance of each function varies between communities at small and large scale geographical and locations depending on farmers’ social-cultural circumstances and rangeland type (Botsime, 2006; Simela et al., 2006). Many communal farmers in Ngqushwa district,
Eastern Cape Province are experiencing a change and transformation of their traditional livestock farming practice and grazing land management. The main reasons behind the change are land degradation, climatic change, shrub invasion and increasing human population resulting in land degradation and reduction of natural resources. Despite these challenges, the communal people continue to use their indigenous knowledge and practices to raise livestock on the communal land. Therefore, any effort of intervention in the development of the rangeland-based communal livestock production systems should first incorporate a thorough understanding of the farmers’ traditional practices, indigenous knowledge and perceptions. In many communal areas of the province, little effort has been made in communal engagements
30 and those efforts made to develop the rangeland based livestock production were not successful because of lack of adequate participation of the farmers in developing strategies and decision making. This study was therefore conducted to measure: 1), the farmers’ knowledge and perceptions of P. incana invasion and impacts on rangeland, livestock production and to measure the effectiveness of the control methods of P. incana and its impacts on the grass biomass production, grass species distribution and soil chemical characteristics in Nyaniso rangeland at Ngqushwa district.
3.2 Materials and Methods 3.2.1 Description of the study area The study was conducted in four adjacent communal areas with extensive invasion of P. incana in their grazing lands of Ngqushwa located in the Eastern Cape, Mgalwana, Nyaniso, Nobumba and Celetyuma under Ngqushwa. The villages have common average temperature, rainfall, and vegetation as they are very close to each other but altitudes are different.
Mgwalana area is located at an altitude of 327 m above sea level with co-ordinates 33°14’ 504”
S, 027° 06’ 288” E, at Celetyuma village the altitude is 215 m located at 33° 16' 374''S, 027°
08’ 287”E, Nyaniso village is 322 m above sea level and is located at (33°14' 287''S, 027° 08’
284''E and lastly Nobumba village was 310 m above sea level and located at 33° 16'
200''S, 027°01'565''E.
The rainfall from these villages ranges between 480 mm-550 mm per annum and mostly falls in summer with peaks in March-April and October-November. The geology of the area is predominantly shale in association with red mudstones of the Ecca Group, Karoo Super Group.
Limestone and calcareous sand soil characterizes the upper-middle catchment. Rock outcrops and plateaus are characterized by shallow litholic soils of the Mispah. The soil consists of predominantly swelling hydrous mica clays with high sodium adsorption ratio (Kakembo,
2004).
31
The vegetation is described as Eastern Thorn Bush-veld and comprises Acacia karoo trees (<
3 m tall), thicket species (e.g. Scutia myrtina, Searsia spp) which form bush clumps, and a dense grass layer comprising of a mixture of species such as Themeda triandra, Sporobolus africanus and Digiteria eriantha (Low and Rebelo1996). The vegetation varies from diverse grasslands with A. Karroo invasion, to dense thickets of A. Karroo scrub and overgrazed grasslands.
3.2.1.1 Sampling procedure for the interview
The extension officer and the chief of the villages were contacted to request for authorization and to make an appointment for the interview.
Four villages (Mgalwana, Nyaniso, Nobumba and Celetyuma) with extensive invasion of P. incana in their grazing areas were surveyed. About 20 households per village were selected for the interview totaling of 80 household surveys from the four villages. The target respondents were livestock holders as they are using the rangeland every time and they have better knowledge about the rangelands than non-livestock keepers. Accordingly, old people were the first preference for the interview as youth ≤35 years old are not well informed about the history of the P. incana invasion.
3.2.1.2 Data collection and statistical analysis
The interview was conducted in Xhosa language. An open and close ended questionnaire was prepared. Famer’s socio-demographic information, livestock ownership, livestock feeding, and resource availability, grazing management systems, conditions of the veld and animals, major constraints on livestock production, livestock species and general trend of P. incana on the rangeland was captured. Data were analyzed using the SPSS statistical software program version 20 (SPSS, 2011). For ranked data, Friedmans’ chi-square test was used. When this test revealed significant variation, a set of sign tests for multiple comparisons of means was
32 performed. Descriptive statistics such as means, standard deviations and percentages were used where appropriate.
3.3 Results and discussion. 3.3.1 Demographic information.
3.3.1.1 Household size, age distribution and educational background.
A household is defined as the combination of man and wife, their children and whoever is dependent on that family for food and his/her/their needs. The additional members may include kin or non kin members (Hog, 1992). The average household size in the study area was 6.1,
6.4, 6.3 and 5.5 for Mgwalana, Celetyuma, Nobumba and Nyaniso villages, respectively. The mean size of the household in the current study site is significantly lower than the reports of
Mndela (2013) in the same study area and this might be due to differences in village sizes.
Data on marital status showed that 70%, 65%, 25% and 31% of the respondents from
Mgwalana, Celetyuma village, Nyaniso and Nobumba respectively, were married (Table 2).
The majority of the farmers in all the villages were older than 50 years (range: 75% at
Nobumba-100% at Mgwalana village) (Table 1). The same results were reported by Mapiye
(2009) in the same Province as the current study. The results revealed that youth ds not participate in agricultural activities as none showed interest and this could be due to the lack of participation at younger ages and less motivation. Lesoli (2011) postulated that less participation of the young people in agriculture provides an evidence of the breakdown of the transfer of indigenous knowledge and skills from the one generation to another. The current study also concurs with the study of Gwelo (2012) that the youth of this generation do not want to take part in agricultural production in Kwezana and Dikidikana villages of the Eastern Cape.
33
However, many studies confirmed that youth involvement in agricultural production is very significant to both optimum food production and knowledge transfer from the old to the young
(Mbata, 2001, Jourbet and Simalanga, 2004 and Lesoli, 2011).
The percentages of farmers who attended secondary school ranged from 20% at Nobumba to
65% at Nyaniso village, whereas farmers who attended tertiary schools ranged from 0%
(Mgwalana) to 15% (Nyaniso) (Table 1). Respondents with tertiary education owned significant higher numbers of livestock than the poor educated ones. The proportion of farmers who attended elementary schools ranged from 10% at Nyaniso to 65% at Nobumba village, while the percentages of illiterate farmers ranged from 0% (Celetyuma) to 15% (Mgwalana).
The level of education in the study area is very poor (Table 1), this implies that the use of the current technology to improve agriculture and the standard of living could be a challenge in these villages. According to Mapiye et al. (2007) and Moyo et al. (2008), literacy levels are a very important determents in livestock production as they coordinates the acceptance of new interventions e.g. on rangeland management practices.
The higher number of livestock ownership by well-educated than the poorly educated respondents of the current study indicates that gradual improvement of levels of education also reduces poverty through farming in communal areas. Gwelo (2012) reported similar results that levels of education in communal areas of the Eastern Cape Province are improving gradually.
The Province of the Eastern Cape has been reported to be dominated by rural areas, therefore, livestock production plays a vital role in the eradication of poverty in rural areas (Beck and
Nesmith, 2001). This confirmed that livestock production in communal areas is regarded as a main source of food and livelihood for those who trade/sell since goats, sheep and cattle are usually slaughtered during traditional ceremonies, funerals, weddings and rituals.
34
Table1. Percentage age distribution, educational and occupational status of the respondents in four villages (Respondents, N= 100).
Age distribution Mgwalana Celetyuma Nyaniso Nobumba
30-40 0 10 5 5
40-50 0 0 15 20
>50 100 90 80 75
Educational status
Illiterate 15 0 10 10
Elementary 55 55 10 65
Secondary 26 40 65 20
Tertiary 0 5 15 5
Occupational status
Grant holder 59 45 45 57
Employee 21 21 20 27
Business 15 29 0 12
No occupation 5 5 35 3
3.3.1.3 Percentage distribution of occupational status.
Nearly all the interviewed farmers in the study areas were not formally employed. They relied on livestock, social grants and pensions for their livelihood. The percentage of pensioner /social grant, business and unemployed respondents ranged from 0%- 29%, 45%-59% and 3%-5% of the selected villages respectively. Most of the respondents at the study area are not employed hence 51% of them live with pension and social grants (Table 1). Since most people have
35 abandoned their crop fields and therefore there is not enough forage for their livestock production due to shrub invasion in the crop fields so income from livestock keeping does not completely compensate for of unemployment. Vast crop fields have been abandoned and the invasion is very high on those areas. This is very detrimental to livestock production as it reduces the forage production resulting in starvation and deaths of animals, according the respondents. This increases the dependence of the unemployed farmers on their grant as invasion is growing at the expense of agriculture.
Table 2. Percentage distribution of marital status and relation to house hold in percentage
(n=20per village).
Marital status Mgwalana Celetyuma Nyaniso Nobumba
Single 10 10 25 30
Married 70 65 25 31
Divorced 20 25 50 39
Relation to head
Head 10 0 0 0
Grandchildren 40 35 35 15
Father or mother 50 65 65 85
3.3.1.4 Livestock ownership
The mean number of female goats, cattle and sheep owned by a household from Nobumba were (21.3, 12.3 and 3.1); Nyaniso (18.3, 9.2 and 2.4); Celetyuma (11.6, 3.9 and 1.4) and
36
Mgwalana (13.1, 4 and 2.7) respectively. Household cattle and goat holdings varied significantly among the villages with Nobumba and Nyaniso having the highest population.
The mean number of goats in all the four communal areas were the highest and the sheep population was the lowest. This could be due to livestock species uses per house hold and forage availability (Table 3). In the current study respondents justified that cattle and sheep population is less than the goat population because of the scarcity of the grazing forage as the because of shrub invasion. Forage availability is the main determinant of animal production in the semi-arid communal areas of South Africa (Gwelo, 2012). Sheep and cattle prefer grazing more than browsing unlike goats that spend more time in browsing (Nyakiri et al., 2005) so therefore high bush invasion hinders grass growth. Similarly, Mndela (2013) reported the lowest population of sheep holdings per household in the Eastern Cape. The mean number of livestock holdings from all the villages in this study were lower than the findings of
Mngomezulu (2009) (cattle= 12, goats=6); Mapiye et al., 2009 from the same province and country. The difference in mean livestock holdings of the current study and previous studies could be associated with, shrub invasion, differences in agro-climatic factors and local preferences of the inhabitants for raising animals.
In as far as the cattle and goat holdings amongst the villages are concerned differences in densities of P. incana and landscape among the villages could be the reason as steep gradients increase the negative impacts of P. incana invasion such as land degradation (Kakembo, 2009).
The mean number of male goats, cattle and sheep owned by a household from Nobumba were
(8.0, 8.4 and 0.5), Nyaniso (6.8, 4.3 and 2.2), Celetyuma (1.3, 1.8, and 2.5) and Mgwalana
(2.4, 1.1 and 0.8) respectively. In all livestock species female population was higher than male population. This is because female animals are sold during emergencies e.g. they are culled during dry winters to buy some supplements and medicines and some are castrated for animal
37 traction for calm purposes (Davie, 2006). Females and few male animals are kept to produce the young ones.
The majority of the respondents keep goats and cattle together (37.5%) or goat species only
(28%) (Table3). However, keeping a mixture of livestock species makes the households’ economy more resilient than a single species (Alary et al., 2011; Solomon et al., 2014).
The low male: female ratio reported in the current study is in agreement with the report of
Gwaze et al. (2010) in the same province. In a study conducted by Gwelo (2012) in the Eastern
Cape, Kwezana location lower mean numbers than the current study were reported with goats having the highest. Differences in the vegetation type and animal husbandry could facilitate the difference. However, goats are tolerant to drought as they have feeding behavior that includes drought–resistant browse species and forages with low nutritional contents (Coppock,
1994).
Furthermore, respondents reported that the population of livestock decreased over the last 10-
20 years (cattle and goats) with goats having the lowest decrease in population number than the rest of the species and P. incana invasion was perceived to be the reason as it is fatal to grass cover (Kakembo, 2004). Smith (2004) reported different results where mean goat population was not affected in bush encroached areas. This could be due to the fact that browsing material increased the forage for goats which are the main feeding source unlike P. incana that is not browsable.
38
Table 3. Livestock holdings (mean± SE) in the four studied villages (n=20 per village).
Livestock Mgwalana Celetyuma Nyaniso Nobumba Cattle
M <3 years 0.45b±0.2 0.6ab±0.2 1.2ab±0.8 2.1a± 0.8
M =3yrs 0.2b±0.2 0.3b ±0.2 2.1ab±0.8 2.2a±0.8
M>3yrs 1.1b ±0.4 1.8ab±0.5 2.2a±0.1 1.1b±0.9
Total 1.8b ±0.7 2.7b ± 0.8 4.3b ±2.4 8.4a±2.4
F<3 years 0.8b±0.2 0.5b± 0.2 1.1b±0.9 2.0a±0.9
F=3yrs 0.4b ± 0.7 0.6b±0.4 1.8ab±0.8 3.1a±1.4
F>3yrs 3.9b±0.8 2.8b±0.9 5.9a±1.5 7.2a±1.7
Total 4.0b±1.1 3.9b±1.1 9.6a±2.9 12.3a±3.5
Sheep
M <2 years 0.3a±0.2 0.5a±0.5 0.5a± 0.1 0.2a±0.2
M=2yrs 0.1a±0.1 1.0a±1.0 0.3a ±0.2 0.4a±0.3
M>2yrs 0.4a±0.2 1.0a±0.9 1.4a±0.9 0.9a±0.6
Total 0.8a±0.4 2.5a±2.4 2.2a± 1.6 0.5a±0.9
F<2 years 0.6a±0.2 0.6a± 0.6 0.3a± 0.2 0.4a±0.2
F=2yrs 0.4a ±0.2 1.0a±1.0 0.7a±0.5 0.3a±0.3
F>2yrs 3.3a±0.9 4a±0.6 3.7a±0.5 3.3a±0.9
Total 2.7a±1.1 1.4a±0.6 2.4a ±1.4 3.1a ±1.2
Goat
M <2 years 3.4a±1.9 1.4b±0.6 2.4ab± 0.9 3.3 a±0.9
M=2yrs 1.2b±0.6 1.1b±0.5 2.0ab ± 0.9 3.3a±0.1
M>2yrs 2.4b±0.8 1.3b±0.9 6.8a±2.1 8.0a±1.8
Total 6.9b±0.8 5.8b ±1.9 12.5 a±4.1 15.0a±3.4
F<2 years 2.7a±0.9 1.8a± 0.6 3.5a±1.3 4.2 a±2.5
F=2yrs 1.9a ± 0.8 2.2a±1.5 4.5a± 2.5 4.4 a± 2.5
F>2yrs 8.5ab±2.6 7.6b±1.4 10.4ab±2.9 12.7a±2.5
Total 13.1b±4.3 11.6b±2.8 18.3a±6.2 21.3a±5.6
Values with different superscript within a row are significantly different (P < 0.05).
39
Table 4. Types of livestock raised by respondents in four villages (n= 20 per village, 80= total)
Livestock species Respondents (%)
Cattle 12.5
Cattle and Goats 37.5
Cattle, Goats & Sheep 16.3
Goats only 28.8
Sheep only 2.5
Goats and sheep 2.5
3.3.1.4 Relative importance of livestock species
Respondents from Mgwalana and Nobumba village revealed that goats are the most important livestock species (P<0.05) followed by cattle and sheep. Household respondents from
Celetyuma and Nyaniso villages indicated that goats and cattle have equal or greater importance than sheep (Figure 1). These findings disagree with the study of Mapiliyao (2010) who reported that sheep were the most important livestock species followed by cattle and goats in the Eastern Cape Province but in a different study area from ours. Although livestock production is diverse, Mndela (2013) also came up with contradictory results that cattle production was the main production system followed by goat production and sheep production system in the Eastern Cape, South Africa. It has been justified by the respondents that different religions results in different livestock commodities raised per house hold.
40
3
2.5
2
1.5 Goats ranks) Cattle 1 Sheep
0.5 Livestock (mean importance Livestock 0 Mgwalana Celetyuma Nyaniso Nobumba
Villages
Figure 2. Mean ranks of livestock importance from the most important (3) to the least important (1).
All villages listed similar reasons for raising livestock species, but the ranking of the reasons were different. The most important reason for raising cattle in Mgwalana was for sale, meat and milk production for consumption followed by the use for draft power. In Celetyuma,
Nyaniso and Nobumba village, cattle are raised primarily for sale followed by meat and milk production and draft power. Income derived from cattle sales is used to support family necessities like taking children to school, buying other food items, and for agricultural activities
(Musemwe et al., 2010). In support of the current results, Nthakheni (2006) and Stroebel et al.
(2011) reported that cattle production is mainly practiced for financial security and cash income in the small holder farmers in South Africa. A study conducted in northern Kalahari contradicts with the present study and it was perceived that cattle are primarily raised to produce milk
(Katjiua and Ward 2007). In most of the Xhosa tribes cattle production is mostly practiced for cultural events such as slaughtering for weddings and to pay bride price that is well known as
Lobola in Xhosa language. In a studies conducted Mngomezulu 2010) reported cattle are raised
41 primarily for draft power (Mngomezulu, 2010). However, milk production was the primary priority from studies conducted by Solomon et al. (2007); Katjiua and Ward (2007) or is intended for slaughtering for meat consumption (Kassahun et al., 2008).
As for goat production, respondents from Mgwalana, Celetyuma and Nyaniso raised goats primarily for sale, traditional purpose as the secondary use and prestigious purpose was listed thirdly whereas Nobumba village ranked traditional ritual as the primary use and sale was the secondary and lastly prestigious purpose was list important (Table 5). According to Libala
(2015), the ritual purposes are almost the same as the slaughtering of goats during traditional functions like introduction of a new born baby to ancestors (Imbeleko).
The report from our study compares well with the observations by Webb and Mombolo (2004) in Mpumalanga province that goats are primarily raised for sales/ income generation and Libala
(2015) in the Eastern Cape, South Africa. Nevertheless, meat production was the main purpose for raising goats in Namibia (Katjiua and Ward 2007) and in the sand River catchment, South
Africa (Shackleton et al., 2005). It is however postulated in the current research that differences in priorities for goat keeping might be due to differences in religion per respondents.
All villages primarily raised sheep for sale and meat production. Many studies concur that sheep production is primarily for cash generation (Kunene and Fossey, 2006; Beyene et al.,
2014) for meat and lastly for wool production in KwaZulu-Natal province of South Africa.
According to Beyene et al. (2014), livestock species diversity per house hold can be used as a measure of economy and the capacity to react to risk than those who have one species (Alary et al., 2011) hence most the farmers raised different species. Some of the respondents revealed that keeping a mixture of livestock species allows wide range of benefits from animal production. In support of the results Dovie et al. (2006) postulated that subsistence farmers in
42 the Southern Africa raise a mixture of livestock species to increase the choices of food products as well as the income.
Table 5. Relative importance (mean ranks) of the purposes for rearing livestock as ranked by the respondents (n= 20 per village).
Livestock Mgwalana Celetyuma Nyaniso Nobumba
Cattle
Attribute Sale 1.7d 1.6d 1.8c 1.9c
Lobola 3.6a 3.4a 3.7a 3.4a
Meat & Milk 1.9d 2.0c 2.0c 2.0b
Prestige 3.0b 2.ab 2.7b 2.3b
Draft power 2.5c 2.0c 3.0b 2.0b
Goat
Sale 1.8c 1.7c 1 .9c 2.1b
Traditional purposes 2.4b 2.1b 2.2b 1.4c
Prestige 3.5a 3.7a 2.4a 2.5a
Sheep
Sale 1.6c 1.8b 1.5c 2.9d
Meat 1.9c 2.9a 2.3b 2.5c
Prestige 2.5a 3.0a 3.2a 3.4a
Wool production 2.0b 2.7a 3.0a 2.0b
Values with different superscript within a column are significantly different (P< 0.05).
43
3.3.1.4 Constraints on livestock production. The listings of the limiting factors for raising livestock by respondents from the four communal areas are similar. However, the rankings were different (Table 6). Respondents from Mgwalana village regarded drought as the primary limiting factor for livestock production followed by shortage of feed and shrub invasion. At Celetyuma drought was the primary limiting factor, whereas feed shortage, shrub invasion, predation and diseases were perceived to be the second most important limiting factors (Table 6). At Nyaniso village respondents regarded drought as the single most important constraint followed by feed shortage, predation and diseases, and shrub invasion, respectively. Respondents from Nobumba perceived that predation was the primary limiting factor to livestock production followed by shrub invasion and disease outbreak (Table 6).
The report from our study contracts with the report of many researchers (Kassahun et al., 2008;
Niguse, 2008 and Libala, 2015) but contrasts from the reports of Mngomezulu (2010) and
Gwelo (2012) where feed shortage and diseases were the primary constraints reported (Table
6).
Repeated droughts have elevated other challenges of the range such as P. incana invasion, feed shortages, and predation of small stock by jackals that hide from P. incana and animal diseases.
The amount of invasion have a great effect on how well the prey may see a predator and escape it (Kunkel and Pletscher, 2000; Creel and Winnie, 2005).
44
Table 6. Attributing factors (mean rank) to livestock production as perceived by respondents
CHALLENGES Mgwalana Celetyuma Nyaniso Nobumba
P. incana invasion 2.4b±0.7 2.0b±0.7 3.5a±2.3 2.1b±0.8
Feed shortage 2.2b±0.7 1.7b±0.7 2.0c±0.9 2.6a±0.9
Predation 3.0a±0.9 2.1b±0.8 2.9b±0.9 1.9c±0.8
Drought 1.8c±0.7 1.4b±0.7 1.8c±0.7 2.6a±1.0
Diseases 3.4a±1.0 2.0a±0.7 2.8b±0.9 2.1b±0.7
Values with different superscript within a column are significantly different (P< 0.05).
3.3.1.5 Animal feeding and supplementation.
Crop residues are importantly used as supplements by smallholder farmers during dry seasons in the mixed systems in subtropical Africa and Asia (Valbuena et al., 2012). Nonetheless, in the current study few (18%) of the respondents practiced crop production therefore most farmers lacked the crop residues as they are the cheap supplements for their livestock during dry periods. Maize stalks were rarely used by the farmers as most of them have abandoned their crop fields. Lucerne and barley were used as supplements by those who afford to buy even though most of the respondents could not afford to buy supplements and as a result livestock usually starve and die sometimes more especially the pregnant ones.
45
3.3.1.6 Mean ranks of factors to rangeland degradation as perceived by farmers.
Many respondents revealed that degradation has taken place in many parts of Ngqushwa
(formerly Peddie) communal areas. Although the listings of contributing factors were similar, their rankings differed greatly among the four villages (Table 7). Mgwalana respondents perceived P. incana invasion to be the primary cause of the rangeland degradation and the least cause to be overgrazing. Respondents revealed that P. incana invades mostly the drier areas as a result low densities are found close to river banks so therefore drought speeds up the invasion.
Celetyuma respondents perceived that P. incana invasion, topography and animal type as the primary cause of range degradation, followed by overgrazing. Similar findings were reported from a study conducted in Ethopia by Kassahum et al. (2008) and Ward (2005) that shrub infestation is the major contributory factor. The impact of woody plant was reported by Ward
(2005); Wigley et al. (2009); Kgosikoma et al. (2012) and Mndela (2013). It has been perceived by the farmers that small open areas frequently receive grazing pressure as invaded areas have low or no forage for grazing.
Some of the respondents also testified an alarming increase of less palatable and poisonous plant species which are very deadly to the animals upon rummaging e.g. kronxini poisonous plant. Kronxini is an evergreen poisonous plant with purple inflorescence, narrow and small leaves. It grows up to 25- 30 cm on average.
In addition, almost all the respondents revealed that P. incana invasion kills the grass due to soil water competition and consequently results in loss of forage leading to bare patch development. This is supported by the report of Kakembo (2004) that related P. incana invasion to severe reduction of grazing capacity and increased erosion.
In Nyaniso village respondents observed topography as the primary causes followed by animal type and climate and P. incana invasion being the least factor, they further justified that they
46 observe a lot of gullies on steep areas. The respondents from Nobumba village revealed topography as the primary contributory factor, P. incana invasion and climate as the second contributory factors and overgrazing and animal type were the list factors. This is in line with the report by Kakembo (2004) that steep P. incana invaded areas are eroded. In the Thorn bush areas, Libala (2015) reported contradictory findings compared to the current study that topography is the least important factor of range degradation. Variation of woody plant species and in the climate, soil type of the study areas might have played a big role.
The respondents from the villages indicated that the livestock numbers were low but the stocking rate was high due to crossover of other livestock from the other villages and that resulted to overgrazing. Overgrazing is a threat to veld of Southern Africa and has been widely reported in Kenya and Eastern Ethiopia as a threat to many rangelands (Wasonga et al., 2011;
Baars and Aptidon, 2002).
Table 7. Mean ranks of perceived factors of rangeland degradation (respondents, n = 80).
Factor Mgwalana Celetyuma Nyaniso Nobumba
Overgrazing 3.6a±1.1 2.1b±0.8 2.8b±0.1 2.8a±0.1
Animal type 3.0 b±1.0 1.8c±0.8 2.4c±1.0 2.6a±0.1
Climate 2.4 c±0.9 2.8a±0.9 2.6bc±0.9 2.2b±0.1
Shrub invasion 1.8d±0.6 1.7c±0.8 3.5a±2.3 2.1b±0.1
Topography 3.2b±1.1 1.9c±0.8 1.9d±0.7 1.9c±0.1
Values with the same superscripts moving down the column show no significance difference
(P> 0.05).
47
3.3.1.7 Rangeland uses Rangelands have various purposes in the rural areas. Respondents from all villages firstly ranked browsing/grazing, fire and wood collection for making kraals as the primary use of rangelands. The respondents revealed that grazing is available throughout the year excluding during the winter season when grass quantity and quality declines. According to Solomon et al. (2007) rangeland natural resources are mostly used by resource poor farmers and grazing was the primary use. Wood collection is practiced in the winter season and used for cooking to save electricity and paraffin. The collection of wood for fire increases during June and
December when people are doing their traditional /ritual events like wedding ceremonies and boys’ traditional circumcisions. Collection of wood for building kraals is done during the rainy season so as to harvest woods with green leaves for wind breaks. O’Farrel et al. (2007) postulated that communal famers use rangelands primarily for grazing and medicinal purposes.
In a study conducted by Lesoli (2008) and Gxasheka (2014) in the same province of the current study, grazing was cited as primary use of the rangeland (81%) and collection of medicinal plants as the secondary use of rangeland. In contradiction, Libala (2015) found that woody plant collection for fire and kraal making were ranked thirdly in her study conducted in the
Eastern Cape, South Africa. The differences between the two reports could be clarified by differences in classes of respondents from different study sites as rich ones might not rely much on the rangelands.
In the remote areas of the Ethiopia where water tanks are not easily accessible, rangelands are mainly used as a source of water for drinking by households, livestock and wild ungulates
(Amaha, 2006). The use of rangelands for medicinal purposes and cow dung collection were generally ranked as the least use of rangelands and this concurs with the results reported by
Libala (2015). In the present study the major resources from rangelands were grass for consumption by livestock, water but not every season, fire wood for cooking and making kraals
48 and traditional medicines. In terms of resource availability 41% of the respondents stated that grass is almost enough during rainy seasons but it is scarce during dry seasons but green patches along valleys are mostly found, said the respondents.
Table 8. Mean ranks of rangeland uses starting from the most important to the least important across all the villages.
Purpose Mgwalana Celetyuma Nyaniso Nobumba
Grazing 1.5d 1.1d 1.1e 1.0d
Fire wood 2.1c 2.1c 2.1d 2.3c
Fencing 3.2b 3.1b 3.1c 3.3b
Medicine 3.2b 3.3a 3.3b 3.4b
Dry cow dung 3.9a 3.0b 4.3a 4.3a
Values with the same superscripts moving down the column show no significance difference
(P>0.05).
3.3.1.8 Conditions of the rangelands, challenges and access of rangeland. Respondents among all the communities had different opinions on the rangeland conditions but most (71%) of them perceived their rangelands to be in poor state and 19% of them rated them as moderate and the rest rated them to be good. The major problem reported was the shortage of forage due to high P. incana invasion. They reported that invasion of P. incana increased over period of 10-20 years ago. Gxasheka (2014) found similar report from his study
49 in the same province and country that Euryopsy floribundus increased in density. Wigley et al.
(2009) postulated that woody plants increase as time goes by.
Recurrent drought, grazing and climate change were perceived to be the most catalyst of the increase of shrub that suppresses the forage. In support of the change in climate of South Africa,
Meadows and Hoffman (2002) postulated that climate change has been observed and rainfall and temperatures varied significantly from the past records.
Respondents from Mgwalana village perceived that over 10-25 years ago rangelands were divided into camps and the situation of invasion and forage was better than the current situation.
Similarly, lack of the paddocks in the rangeland is one of the key factors that negatively affect grazing management, rangeland performance and hereafter livestock production (Samuel,
2007; Nqeno, 2008). In addition, rangeland partitioning prevents cattle theft and restoration of the rangelands (Mapiye et al., 2009, Bennet et al. (2010). In the same country, bush encroachment is perceived to be an advantage by Katjiua and Ward (2007) as it provides browse for goats and cattle. In Ethiopa Solomon et al. (2007) concurs with the current study that cattle and sheep production are not favored by bush encroachment. All the respondents reported that one of the reasons of this alarming increase in P. incana invasion is the lack of control of the invasion. All the communities were reported to be invaded by the poisonous plants like kronxini by the respondents. In a study conducted by Solomon et al. (2014) in the same country and province, the same poisonous have been found to be problematic to their rangelands and livestock.
In addressing the question of access of the range by farmers, the farmers accessed the range by the being the member of the village in all the villages. One more problem faced by the farmers was the crossing of the livestock from one village to another resulting in over grazing. The aforementioned deed have been reported by Solomon et al. (2007) that overgrazing result to shrub invasion.
50
Almost all the farmers anticipated that if the government can employ communal people to remove the shrubs that can help improve the conditions of the rangelands as it used to be during the Lennox Sebe government time. During that time the invasion was kept lower than now.
Respondents (88 %) reported that the invasion is very high in the areas that used to be crop fields and steep landscapes even though it is found next to houses.
During the survey respondents reported that there is no daily, monthly or seasonal community management of the rangelands. Almost all the respondents requested training in veld management.
3.3.1.9 Perception of P. incana invasion on livelihood of farmers. The invasion of P. incana is perceived differently among the four communal areas.
All respondents from Nobumba village perceived that during their teenage stage the P. incana density was not in the grazing lands but only on steep gradients of the rangeland. They observed the invasion in the grazing lands in the early 1990s. Gxasheka (2014) reported the same results that invasion of Eryopsy floribandus increased gradually over years in a study conducted in the
Eastern Cape of South Africa. Respondents from Mgwalana perceived that the invasion was visible in the grazing lands during their early ages (10-20 years ago) even though it was not significant like the present situation. After the abandonment of crop fields the invasion was observed to be heavy. Mgwalana was perceived to have highest densities and Nobumba had lowest density. One of the reasons of crop abandonment was the climate change, settlement relocating and drought so they related the increase of invasion to the combination of the three factors.
In terms of weather conditions all the respondents perceived that there is a great change, there are cold and prolonged winter seasons with great winds compared to previous decades. About
83% of the respondents said the rainfall was less effective than before. There are either floods or not enough rainfall. Niguse (2008) is in agreement with findings from the current study that
51 possible factors of shrub invasion in rangeland ecology are the climate changes overgrazing and recurrent drought.
The situations of Mgwalana, Celetyuma and Nyaniso were the same as they are next to each other and turn to share their grazing lands.
The other reason perceived by the respondents was the lack of control of the shrub by the communal people in relation to the previous decades.
3.3.1.10 Uses of the P. incana and environmental impacts The shrub (P. incana) is reported not to be used as an animal feed source by the respondents.
Some respondent revealed that they rarely use it as the source of fire. In the olden days people used to use it as medicine to treat fever.
In the grazing land the shrub was perceived to decreases the grazing space, basal cover of the grass and substitutes the palatable grasses, perennial grasses species like Themeda triandra
(Iqude in Xhosa) with Karroiod species and annual grass species. About 76 % of the respondents perceived that P. incana results in soil erosion on steep gradients. Soil crusting and deep gullies are usually noticed by the farmers in invaded areas. Kakembo (2004) reported the same findings that P. incana results to the above mentioned challenges like soil crusting.
Angassa and Oba (2008) concurs with the current study that he decline of forage production and change in species composition is attributed it to the rapid increase of woody plants.
The gullies are reported to facilitate livestock injuries and some deaths more especially during rainy weather. Ngulube (2003) reported that communal farmers are knowledgeable about the degradation of their of the rangelands
This shrub is a perennial plant so its impact is everlasting in the environment of Ngqushwa area. The shrub spreads through the blowout of the seeds by wind. Predators like jackals turn to hide around homesteads with P. incana as it is very dense making easy hunting of the livestock. However, this invasion results in hiring of the people to look after small stock even
52 though most of the crop fields have been abandoned as they were the main reason for hiring of the people to look after livestock in those communal areas according to the respondents. Indeed
P. incana invasion had made the lives of the farmers to be more difficult.
3.4. Conclusion It was concluded that Ngushwa communal farmers were partially knowledgeable about the effects of P. incana invasion and their livelihoods in agriculture. It was concluded that P. incana was indigenous to the study area and the density has increased significantly over the last 10-20 years. It was concluded that recurrent drought and climate change have resulted in the increase of the P. incana density. P. incana invasion has detrimental effects on rangelands of the study area and consequently in livestock production and species diversification as small stock predation by jackals was promoted by P. incana invasion as they hide on the shrub, therefore it was concluded that P. incana invasion reduces the choices of farmers to different food products, the income, savings and security more especially during drought periods.
However, the livelihoods of the respondents were affected by P. incana invasion as most of them seem to be unemployed.
3.5. Recommendation. Rehabilitation of the degraded areas may be useful.
Installation of grazing camps and mechanical removal of P. incana may help to improve low forage production and livestock production.
53
References Alary, V., Corniaux, C., and Gautier, D., 2011. Livestock’s contribution to poverty alleviation:
How to measure it? World Development, 39: 1638–1648.
ALASA, 1998. Handbook of feeds and plant analysis. Palic, D. (Ed).
Amaha, K.G., 2006. Characterization of rangeland resources and dynamics of the pastoral
production systems in the Somali region of eastern Ethiopia, PhD’s thesis. University
of the Free state, Bloemfontein, South Africa.
Baars, R.M.T., and Aptidon, S.M., 2002. Pastoralists perceptions of rangeland degradation in
Eastern Ethiopia.Nomadic Peoples, 6: 144 – 157.
Beck, T., and Nesmith, C., 2001. Building on Poor People’s Capacities: The Case of Common
Property Resources in India and West Africa. World Development, 29: 119-133.
Bennett, J., Ainsilie, A., and Davies, J., 2010. Fenced in: Common property struggles in the
management of communal rangelands in central Eastern Cape Province, South Africa.
Land use Policy, 27: 340-350.
Bester, J., Matjuda, L.E., Rust, J.M., and Fourie, H.J., 2003. The Nguni: A case study. In FAO,
2003: 45-68.
Beyene, S.T., Mlisa, L., and Gxasheka, M., 2014. Local Perception of Livestock Husbandry
and rangeland degradation in the highlands of South Africa Implication for
Development Interventions. Journal of Human ecology, 47: 257-268.
Beyer, T., Antoch, G Bockish, A., and Stataus, J., 2004. Optiomized Intravenius conytrast
administration for dog nostic whole body for diamagnetic.
Botsime, B.D., 2006. Influence of Agro-Ecological Region on Selected Anthropometrical
Measurements of Nguni in South Africa, PhD Thesis, University of Pretoria.
Coppock, D.L., 1994. The Borana plateau of southern Ethiopia: synthesis of pastoral research,
development and change, 1980– 91. ILCA (International livestock Centre for Africa)
Systems study 5. I.L.C.A, Addis Ababa, Ethiopia, 299.
54
Creel, S., and J. A., and Winnie, J.R., 2005. Responses of elk herd size to fine-scale spatial and
temporal variation in the risk of predation by wolves. Animal Behavior, 69: 1181–1189.
Dovie, D.B.K., Shackleton, C.M., and Witkowski, E.T., 2006. Valuation of communal area
livestock benefits, rural livelihoods and related policy issues. Land Use Pol, 23: 260–
271.
Goldblatt, P., and Manning, J.C., 2000. Cape plants: A Conspectus of the Cape flora of
Southern Africa. National Botanical Institute, Cape Town and Missouri Botanical
Garden, St Louis.
Gwaze, F.R., Chimonyo, M., Dzama, k., 2010. Estimation of goat production potential and
efficiency in the resource poor communal farmers of the Eastern Cape Province of
South Africa. Tropical Animal Health Production, 42: 1235-1242.
Gwelo, F.A., 2012. Communal farmers’ perceptions of livestock feeding and rangeland
resources management and dynamics of mineral levels of soils, forage and Nguni cattle
blood serum in two communal areas of the Eastern Cape, South Africa. MSc
Dissertation, University of Fort Hare, South Africa.
Gxasheka, M., 2014. Euryops floribundus Encroachment in Eastern Cape communal
Rangelands: Indigenous and Scientific Understanding of Effects on Range Ecology,
and Food security and climate. Msc Dissertation, South Africa: University of Fort hare.
Hogg, R., 1992. Cooperative development in the southern Rangelands: past experience and
future development. Final Consultancy Report. Fourth Livestock development project,
Addis Ababa, Ethiopia, 76.
Hudak, A.T., 1999. Rangeland mismanagement in South Africa: Failure to apply ecological knowledge. Human ecology, 27: 55-78.
Joubert, B., and Simalanga, T.E., 2004. Mechanizing agriculture using animal traction and
small scale irrigation. In: Empowering farmers with animal traction (eds Kaumbutho,
55
P., Pearson, A. and Sinalinga, T). Proceedings of a workshop of the Animal Traction
Network for Eastern and Southern Africa (ATNESA) held at Mpumalanga, South
Africa, 249–252.
Kakembo, V., 2004. Factors affecting the invasion of Pteronia incana (Blue bush) onto
hillslope in Ngqushwa (formerly Peddie) District, Eastern Cape, Unpublished PhD
thesis, Rhodes University, Grahamstown.
Kakembo, V., 2009. Vegetation patchiness and implications for landscape function: The case
of Pteronia incana invader species in Ngqushwa Rural Municipality, Eastern Cape,
South Africa. Catena, 77: 180-186.
Kakembo, V., Palmer A.R., and Rowntree K., 2006. The use of high resolution digital imagery
to characterize the distribution of Pteronia incana invader species in Ngqushwa
(formerly Peddie) District, Eastern Cape, South Africa. International journal of
Remote sensing, 27: 2735-2752.
Kassahun, A., Snyman, H.A., and Smit, G.N., 2008. Impact of rangeland degradation on the
pastoral production systems. Livelihoods and perceptions of the Somali pastoralists in
Eastern Ethiopia. Journal of Arid Environment, 72: 1265–1281.
Katjiua, M., and Ward, D., 2007. Pastoralists’ perceptions and realities of vegetation change
and browse consumption in the northern Kalahari. Namibia. Journal of Arid
Environment, 69: 716–730.
Kgosikoma, O. E., Harvie1, B. A., and Mojeremane, W., 2012. Bush encroachment in relation
to rangeland management systems and environmental conditions in Kalahari ecosystem
of Botswana. African Journal of Agricultural Research, 7: 2312-2319.
Kunene, N.W., and Fossey, A., 2006. A survey on livestock production in some traditional
areas of Northern KwaZulu Natal in South Africa. Livestock Research for Rural
Development, 18: 1265–1281.
56
Kunkel, K. E., and Pletscher, D. H., 2000. Habitat factors affecting vulnerability of moose to
predation by wolves in south eastern British Columbia. Canadian Journal of Zoology,
78: 150–157.
Lesoli, M.S., 2008. Vegetation and soil status, and human perceptions on the condition of
communal rangelands of the Eastern Cape, South Africa. MSc Thesis, University of
Fort Hare.
Lesoli, M.S., 2011. Characterization of communal rangeland degradation and evaluation of
vegetation restoration techniques in the Eastern Cape, South Africa. PhD. Thesis,
University of Fort Hare, Alice, South Africa.
Libala, N., 2015. Bush encroachment in the semi-arid communal grazing land of Eastern Cape
and farmers perceptions of causes and livelihood impacts. MSc Dissertation, South
Africa: University of Fort Hare.
Low, A.B., and Rebelo., AG., 1996. Vegetation of South Africa, Lesotho and Swaziland.
Department of Environmental Affairs & Tourism, Pretoria.
Lubke, R.A., and Breenlamp, G., 1996. Eastern Thorn Bushveld. In: Low AB and Rebelo,
AG. (eds). Vegetation of South Africa, Lesotho and Swaziland. Department of
Environmental Affairs & Tourism, Pretoria, 24-25.
Mapiliyao, L., 2010. Sheep Production Practices, Flock Dynamics, Body Condition and
Weight Variation in Two Ecologically Different Resource Poor Communal Farming
Systems. MSc Dissertation, South Africa: University of Fort Hare.
Mapiye, C., Chimonyo, M., and Dzama, K., 2009. Seasonal dynamics, production potential
and efficiency of cattle in sweet and sour communal rangelands of South Africa.
Journal of arid environment, 73: 529-536.
57
Mapiye, C., Chimonyo, M., Muchenje, V., Dzama, K., Marufu, MC., and Raats, JG., 2007.
Potential for value-addition of Nguni cattle products in the communal areas of South
Africa: a review. African Journal of Agricultural Research, 2: 488-495.
Mbata, T.N., 2001. Determinants of animal traction adoption in traditional agriculture: An application of the multivariate probity procedure of Lesotho. Development Southern Africa, 18: 34–41.
Meadows, M. E., and Hoffman, M.T., 2002. The nature, extent and cause of land degradation
in South Africa: Legacy of the Past, lessons for the future? Area, 34: 428-437.
Mndela, M., 2013. Evaluation of range condition, soil properties, seed banks and farmers
perceptions in Peddie communal rangeland of the Eastern Cape. MSc Dissertation,
University of Fort Hare, South Africa.
Mngomezulu, M., 2010. Formal Marketing of Cattle by Communal Farmers in the Eastern
Cape Province of South Africa, Can They Take Part? Animal Production Systems Group.
MSc Dissertation, South Africa: University of Fort Hare.
Moyo, B., Dube, S., Lesoli, M., and Masika, P.J., 2008. Communal area grazing strategies:
institutions and traditional practices. African Journal of Range and Forage Science, 25:
47-54.
Musemwa, L., Mushunje, A, Chimonyo, M., and Mapiye, C., 2010. Low cattle market off-take
rates in communal production systems of South Africa: Causes and mitigation
strategies. Journal of Sustainable Development in Africa, 12: 209–226.
Niguse, B.N., 2008. Ecological Impacts of Bush Encroachment on Rangeland Ecosystem: The
Case of Hallona and Medhacho Pastoralist Associations in Borana Lowlands. Msc,
Addis Ababa University School of Graduate Studies.
58
Nqeno.N., 2008. Reproductive Performance of cows in the sweet and sour veld types under
communal production in the Eastern Cape Province, South Africa. Msc, University of
Fort hare, South Africa.
Ngulube, P., 2003. Using the SECI knowledge management model and other tools to
communicate and manage tacit indigenous knowledge. Innovation, 29: 21-30.
Nthakheni, N.D., 2006. A livestock production systems study amongst resource–poor livestock
owners in the Vhembe District of Limpopo Province. PhD Dissertation, University of
the Free State, Bloemfontein, South Africa.
Nyakiri, D.M., Kitalyi, A., Wasonga, V.O., Isae, I., Kyagaba, E., and Lugenja, M., 2005.
Indigenous techniques for assessing and monitoring range resources in East Africa.
Pimental, D., McNair, S., Janecka, J., Wightman, J., Simmonds, C., O’Connell, C., Wong, E.,
Russel, L., Zern, J., Aquino, T., and Tsomondo, T., 2000. Economics and
environmental threats of alien plant, animal and microbe invasions. Agriculture,
Ecosystems and Environment, 84: 1–20.
Samuel, M.I., Allsopp, N., and Knight, R.S., 2007. Patterns of resources use by livestock during
and after on the commons of Namaqualand, South Africa. Journal of arid
Environment, 70: 728-739.
Shackleton, C.M., Shackleton, S.E., Netshiluvi, T.R., and Mathabela, F.R., 2005. The
contribution and direct-use value of livestock to rural livelihoods in the sand River
catchment. South Africa. African journal of Rangeland and Forage science, 22: 127-
140.
Simele, L., Montshwe, B.D., Mahanjan, A.M., and Tshuwa, M.P., 2006. The livestock
production environment in the South African smallholder sector. New challenges for
the animal science industries. SASAS 41st Congress Abstracts, 66.
59
Smit, G.N., 2004. An approach to tree thinning to Southern African savannas for long term
restoration from bush encroachment. Journal of Environmental Management, 71: 179–
191.
Solomon, B.T., Mlisa, L., and Gxasheka, M., 2014. Euryops floribundus Encroachment in
Eastern Cape communal Rangelands: Indigenous and Scientific Understanding of
Effects on Range Ecology, and Food security and climate. Msc Dissertation, South
Africa: University of Fort hare.
Solomon, T.B., Snyman, H.A., and Smit, G.N., 2007. Cattle management practices and
perceptions of pastoralists towards rangeland degradation in Borana zone of Southern
Ethiopia. Journal of Environment Management, 82: 481–494.
SPSS, 2011. Statistical package for social science, version 20, USA.
Stroebel, A., Swanepoel, F.J.C., and Pell, A.N., 2011. Sustainable smallholder livestock
systems: A case study of Limpopo Province, South Africa. Livestock Science, 139:
186–190.
Van Auken, O.W., 2000. Shrub invasion of North American semiarid grasslands. Annual
Review of Ecology and Systematics, 31: 197-215.
Valbuena, D., Erenstein, O., Homann, S., Abdoulaye, T., Claessens, L., Duncan, A.J., Gérard,
B., Rufino, M.C., Teufel, N., Rooyen, A. van and Wijk, M.T. van., 2012. Conservation
agriculture in mixed crop-livestock systems: Scoping crop residue trade-offs in sub-
Saharan Africa and South Asia. Field Crops Research, 132: 175-184.
Ward, D., 2005. Do we understand the causes of bush encroachment in African savannas?
African Journal of Range and Forage Science, 22: 01-105.
60
Wasonga, V.O., Nyariki, D.M., and Ngugi, R.K., 2011. Assessing socio-ecological change
dynamics using local knowledge in the semi-arid lowlands of Baringo District, Kenya.
Environment Research Journal, 5: 11 – 17.
Webb, E.C., and Mamabolo, M.J., 2004. Production and reproduction characteristics of South
African indigenous goats in communal farming systems.
Wigley, B.J., Bond, W.J., and Hoffman, M.T., 2009. Bush encroachment under three
contrasting land –use practices in mesic South Africa savanna. A Journal of ecology,
47: 62-70.
61
Chapter 4: Effects of Pteronia incana (Blue bush) invasion on grass biomass production, species distribution and soil chemical characteristics under systematic control methods.
Abstract The objective of this study was to investigate P. incana (Blue bush) invasion control methods on grass species distribution, herbage production and soil chemical characteristics. The experiment was conducted in a 270 m x 100 m trial site that was established in 2014. The area was divided into 3 open (grazing) and 3 fenced (rested) plots each having an area of 45 m x
100 m established down a slope gradient. Each plot was divided into four equal subplots to apply the control treatments. Therefore, the trial layout was a stratified block experiment of four treatments replicated three times. The four control treatments applied to P. incana were chopped and rested (CR), rested without chopped (RWOC), grazed and chopped (GC), grazed without chopped (GWOC). Species composition was not affected (P>0.05) by the treatments applied. The herbage height and basal cover had greater values (P<0.05) under rested+ chopped
(CR) followed by grazed and chopped (GC). Grass biomass production and essential nutrients showed a greater concentration (P<0.05) under CR treatment than any treatments applied. It was concluded that chopping and resting (CR) treatment was the most effective treatment in controlling P. incana invasion and allowing recovery of the herbaceous vegetation.
Key words: Shrub invasion, bare patch, grass biomass, resting, grazing, and chopping.
4.1 Introduction Shrub invasion has been widely reported in the savanna ecosystems of the world during the past few decades. Shrub invasion can be defined as a successful colonization and expansion of one or more indigenous and/ or exotic species of usually dwarf woody growth forms on lands that were previously dominated by other native vegetation species (Gxasheka et al., 2014).
This term is synonymously used with bush or woody plants encroachment or thickening
62 although the later refers mainly to the gradual increase in the density and cover of the existing woody plants in the ecosystem. Under normal circumstances, rangelands are dominated by grasses interspersed with woody plants of different species. But this could change to a state where the rangelands become dominated by few woody species that increase in both cover and density.
Many researchers indicated that shrub invasion on rangelands appears to result from any of a number of distinct factors and/or the interaction of multiple factors and these are mainly recognized as plant and ecosystem related factors.
Grazing has been proved to be a crucial mechanism underlying plant-plant interaction in arid and semiarid environments. Normally, overgrazing results in replacement of palatable perennial by less palatable annual grass species, reduction in biomass production and bare sites develop where woody seedlings are able to establish (Pelgrave, 2002; Graff et al., 2007 and
Solivers et al., 2011). However the frequency of fire is lessened as it increases with biomass production and as a result woody plants multiply (Van Auken, 2009).
Leguminous trees facilitate the increase in abundance of invasive trees due to their nitrogen fixation making the conditions conducive to tree growth and that leads to their multiplication
(Lesoli et al., 2013).
Shrub invasion has severe outcomes in food security and income generation in farmers as it affects agriculture (Ward, 2005). The amount of invasion have a great effect on how well the prey may see a predator and escape it (Kunkel and Pletscher 2000; Creel and Winnie, 2005).
Several studies reported that woody plant invasion decreases stream flow (Tennesen, 2008) and modifies ecosystem water balance as most of the invaded areas have bare patches, therefore the level of infiltration is very low, e.g. Juniperus virginiana expansion into grasslands decreases herbaceous species diversity in the study conducted in Brazil (Linneman and Palmer, 2006). However, changes in soil hydrological properties and nutrient cycles result
63 in shrub invasion (Bekele et al., 2006); (Axmann and Knapp, 1993). Increased rates of shrub and bush encroachment will lead to arid, semi-arid and savanna and wood lands desertification
(Eldridge et al., 2011).
One of the invasive species that is spreading abundantly on parts of South African grasslands is P. incana. The species is distributed from the Eastern Cape westwards to Namaqualand
(Goldblatt and Manning, 2000). In recent years ago, P. incana has been spreading on extensive rangelands of the Eastern Cape. P. incana is indigenous to Nama Karroo regions of South
Africa, successfully invading thicket and natural grassland (Kakembo et al., 2006). P. incana is a perennial woody shrub belonging to the Asteraceae family. The grey-leaved shrub has small, thin and white-wooly leaves. The yellow flower heads are discoid in shape and carried solitary on branch tips and its flowering time is mainly during September to October. High density of P. incana is found in Ngqushwa grazing land and has been there for more than 20 years more especially on south oriented aspects (Kakembo, 2004). P. incana invasion has been associated with rangeland degradation in the steep gradients of the Eastern Cape, South Africa
(Kakembo, 2004).
Invasion of P. incana may threaten livestock production, food security and livelihood of the communal people who depend on rangeland resources for food production. However, not many studies have been conducted to investigate different control treatments on the rangeland ecosystems, their impacts on the grass production, soil chemical characteristics and bare patch development.
Although the effects of herbivory, clipping the P. incana shrub and resting the veld on grass biomass production, height and diameter have been studied individually, little information exists about how these different factors interact.
64
4.2 Materials and Methods
4.2.1 Description of the study site
The study was conducted in Nyaniso communal area in Ngqushwa district, Eastern Cape. The area is situated at the south east of the Ngqushwa town. Nyaniso village, Ngqushwa district is situated at 33°14’ 204” S and 27° 07’ 466” E and is situated at 311m above sea level.
The average temperatures range from 19.3-25.8°C and the average rainfall is 412 mm per year and it mostly falls in summer. The vegetation of Ngqushwa district is dominated by woody vegetation including P. incana, Scotia and Rhus species. The grass layer is dominated by
Themeda triandra, Eustachys paspaloides and Digitaria eriantha with some forbs and Karroid species.
4.2.2 Experimental layout and data collection.
4.2.2.1 Trial layout and transect establishment
The trial was laid out to investigate the influence of chopping P. incana and grazing on grass species composition, grass biomass production and soil chemical characteristics. Treatments were applied in a block design, applying two chopped subplots and the other two unchopped subplots as their control in an alternating layout within 100m x 45 m plot in a P. incana invaded area and the site was established in February 2014.
All the four subplots combined, were tested on two grazing system treatments (controlled and continuous grazing).
Each block of grazing system block with its four subplots (45m x 25m each) in combination of chopped and unchopped treatments and that was replicated three times.
65
All controlled grazing subplots (45m x 25m) were in a fenced block (100m x 45m) and replicated three times whereas continuous grazing block (45m x 25m) were not fenced. All the controlled grazing subplots were denoted as rested and chopped (RC) and the other one was rested without chopped (RWOC). The continuous grazing subplots were denoted as grazed with chopped (GC) and the other one was grazed without chopped (GWOC) and in combination the plots ended up to 270m down and 100m across the slope. Both controlled grazing and continuous plots were in an alternating manner down the slope as shown in the experimental layout figure below;
66
100 m
45m RWOC RC RWOC RC
GC GWOC GC GWOC
RWOC RC RWOC RC
270 m GC GWOC GC GWOC
RWOC RC RWOC RC
GC GWOC GC GWOC
Figure 2: Layout of the trial plots. Dotted lines demarcate the edge of the
unfenced/continuous grazing plot or subplot and solid lines show fenced and controlled
grazing plots/subplot.
Two fixed transects of 40 m that were separated by 10 m apart were established in each subplot
to monitor species composition and P. incana cover using step point method. On the fenced
plots two exclosures of 1m x1m size were randomly distributed in each subplot to make sure
that grazing is controlled. Within each exclosure two 0.25m2quadrates were put randomly to
measure biomass. Density of P. incana was determined from 5m x 5m quadrates that were
67 placed randomly within each subplot. The density and height of individual shrub plant was measured. All rooted live woody plants were recorded and counted in each quadrate.
4.2.2.2 Soil sampling
Soil samples were collected during forage sampling. Two soil samples per subplot were collected in the subplot. Soil samples were taken from 0cm-20cm deep using soil auger.
Collected samples were oven dried at 60℃ for two days, milled and analysed in the laboratory.
All soil samples were analysed for pH, Mg, Cu, Zn, C, Ca, N, P, K and Fe. Nitrogen was determined with the standard Kjeldahl method using a block digester (Bremner and
Breitenbeck, 1983). Soil P was determined using inductively coupled Plasma (ICP) analysis of extract of soil with 1 % of citric acid (ALASA, 1998). Calcium, Magnesium and Potassium were determined by ICP in the same 1 % citric acid extraction (ALASA, 1998). Cu and Zn were determined using ICP in 0.02 M Di-ammonium EDTA soil extracts (ALASA, 1998). 1m potassium chloride (KC1) 2.5 KC1: 1 was used to determine soil pH.
4.2.2.3 Vegetation sampling
Grass species composition and cover were determined using the step point method as described by Solomon (2007) and Warburton (2011). The nearest plant and basal strikes were recorded from 40 point observations per transect and 80 per subplot since each replica is 45m across.
When the distance of the nearest plant was further than 40cm from the marked step-point, it was recorded as “bare area”. Point observations were spaced at approximately 1m intervals along straight parallel transects approximately 10m apart over the length of the subplot. In each subplot, two 0. 25m2 quadrates were randomly placed to determine the biomass production.
Grasses species within each quadrate were identified and tuft height using a 30cm ruler, diameter and distance between tufts were measured using Vernier calipers. Thereafter grasses were harvested at stubble height, bulked and oven-dried for 48 hours at 80 °C. Dried samples
68 were weighed to measure the biomass yield. The density and height of individual shrub plants was measured. All rooted live woody plants were recorded and counted in each quadrate.
4.2.2.4 Statistical analysis
Vegetation and soil data were analyzed using the general linear models (GLM) procedure of
SAS (2009). Data were analyzed based on a 2 × 2 factorial treatment design within a randomized complete block design. The main effects were grazing/resting and chopping/not chopping. Significant difference between means was estimated by the PDIFF option of SAS
(2009).
The following statistical model was used in vegetation:
Yij = µ + G i +Cj + (G x C)ij + Eij
Where Yij = the dependent variable
µ = overall mean
Gi = the effect due to treatment
Cj = the effect due to season
(G x C)ij = interaction between season and treatments
Eijk = the random error
4.3 Results and discussion. 4.3.1 P. incana density and height distribution in two different treatments. Results of P. incana density were not significantly different (P>0.05) between grazing without chopping (GWOC) (10033.33 shrubs/ ha) and resting without chopping RWOC (10733.33 shrubs/ha) treatment. The reason behind was that randomization of the plots was done in an invaded area. In a study conducted by Annika (2002), shrub densities did not vary with sites so therefore their results are concurrent with ours.
69
In a study conducted in Swaziland by Solomon et al. (2008) the density was found to be moderate at the range of <250-550 shrubs per hectare on the communal grazing areas where as in our study it was very high (>850/ha). However our study site was categorized to be heavily invaded as the density of P. incana in both sites (the rested plus chopped and the grazed plus not chopped) was above the density considered to be high by Solomon et al. (2008) so then therefore this P. incana species needs to be minimized.
Table.4.1 Mean shrub density across the treatments applied in Nyaniso rangeland.
Treatment Shrub density per Range density Height hector range(m)
RWOC 10733.33a 4400-15200 0.2m-0.8m
shrubs/ha
GWOC 10033.33a 3200-36000 0.2m-0.8m
shrubs/ha
S.E 1905.37
Values with same letters along the column show no significant difference (P>0.05).
4.3.2 Species composition in Nyaniso communal rangeland.
A total of 22 herbaceous species were identified, 18 of them were perennial grasses with some sedges, Karroid species, forbs and P. incana. As far as the grazing value is concerned five grass species had high grazing value, seven of them had average grazing value and six had low grazing value. Eustachys paspaloides and Eragrostis chloromelas occurred as the dominant species in the rested plus not chopped treatment. The Eragrostis chloromelas was reported to grow well in previously disturbed open areas (van Outshoorn, 2012). Eragrostis capensis was common in chopping plus resting CR and resting without chopping (RWOC) treatments. This
70 could mean that this species favored grazing exclusion and growing on open areas. Digitaria eriantha was the common species in all the treatments except in plots receiving grazing without chopping (GWOC) treatment where it was rare (Table 4.2). This could mean that Digitaria eriantha was grazed severely since it’s a decreaser species. Decreasers species are palatable grasses (like Themeda triandra and Digitaria eriantha) that are dominant in velds of good conditions but decrease with overgrazing or under grazing (van Outshoorn, 2012).
Themeda triandra had the highest abundance in subplots receiving CR and GWOC than the rest of the treatments. P. incana clearing as well as grazing exclusion could be attributed to the results obtained above. In support of the fore mentioned results van Outshoorn (2012) reported that Themeda triandra is common in open undisturbed and high rainfall areas. However,
Solomon and Mlambo (2010) revealed contradictory findings where they say Themeda trianda is adapted to micro habitats under Acacia brevispica. Nevertheless, expansion in tree quantities reduces the abundance of Themeda triandra (Mugasi et al., 2000; Riginos and Grace, 2008).
However it is postulated from the current study that grasses with tufted root system like Themda triandra compete very weakly with P. incana invasion as it is tap rooted therefore it can access soil resources at parts of the soil. In support of our postulate (Abdallah, 2012; Angassa et al.,
2012) reported that Cynodon dactylon was more prevalent under canopy trees. The creeping root system was claimed to be the reason because it has adventitious root system that is scattered all over the place that helps it in up taking soil resources more than tufted grasses as their root system does not occupy a bigger surface area and that might result in low access of the soil resources (e.g. water) than tufted grasses. According to Mndela (2013) the creeping habit of Cynodon dactylon makes it easy to access the light in inter-tree canopy spaces.
All the above mentioned grass species are palatable and produce high leaf yield and are usually associated with rangelands of good conditions (van Outshoorn, 2012).
71
Mechanical shrub removal and grazing exclusion result in native grass improvement of the rangeland but it produces short term grass community changes (Robson, 1995) as the effectiveness of CR treatment may lose its value over time because new seedlings of P. incana may establish in the chopped areas and have its negative effects to grasses next to it.
72
Table 4.2. Distribution of grass species (mean %) in four different treatments in Nyaniso
communal rangelands.
Species RC RWOC GC GWOC Life form Grazing value
Eragrostis plana R R R R P LGV
Erograstis capensis C C - R P AGV
Eustachys paspaloides C D R R P HGV
Eragrostis chloromelas LC D R LC P AGV
Eragrostis obtuse R - - R WP AGV
Microchloa caffra LC LC LC LC P LGV
Aristida congesta R R - R P AGV
Sporobolus africanus R LC LC LC P LGV
Sporobolus fimbriatus R R R R P LGV
Heteropogon contortus R R R C P AGV
Elionurus muticus R R R R P LGV
Themeda triandra C LC LC C P HGV
Digitaria eriantha LC LC LC R P HGV
Setaria sphacelata. Var. torta - R - - P AGV
Brachiaria serrate + R R R P AGV
Chryopogon serrulatus - R - R P HGV
Cymbopogon plurinodis - - - R WP LGV
Cynodon dactylon R R - + P HGV
Forb LC LC LC R -
Sedge LC R LC R P -
Karroid species R R R LC -
Pteronia incana R LC C R P -
Bare space - - R - - -
D= dominant (>15%), C= common (10%-15%), LC= less common (5%-10%), R= rare (1%-
5%) + = present (<1%) and - = absence. A= Annual, P= perennial and WP= Weak perennial.
AGV= average grazing value, LGV= low grazing value and HGV=High grazing value.
73
4.3.3 Effects of treatments on species composition of selected grass species. The frequency occurrence of Sporobolus africanas, Eragrostis chloromelus, Microcloa caffra and Eragrostis capensis did not show significant differences between the four treatments
(Table 4.3). The abundance of Themeda triandra was significantly (P < 0.05) the highest under the rested plus chopped CR treatment (Table 4.3). This is in agreement with the study conducted in Namibia by Solomon and Mlambo (2010) where Themeda triandra was found to be in different quantities between sub-canopy and open areas encroached by Acacia drepanolobium. In as much as CR treatment is concerned, seeding and seedling establishment is suspected to have taken place to result in highest Themeda triandra abundance in the current study even though bush clearing is ascribed to be the most important intervention.
Eustachys paspaloides abundance is significantly highest in the CR and RWOC treatment.
Nevertheless, it is postulated from the current study that P. incana invasion has little or no effect on the Eustachys paspaloides composition compared to other grass species. Under subplots receiving GWOC Eustachys paspaloides had the lowest abundance. Grazing was the most important factor influencing the species abundance.
Digitaria eriantha was the lowest in the GWOC treatment. The grazing pressure and P. incana invasion impacts could have resulted in variations of Digitaria eriantha among the treatments.
Digitaria eriantha species is categorized under decreaser species and reported to be palatable so selective grazing is suspected to have taken place resulting in low abundance under grazing treatments. Overgrazing results in reduced grass basal cover permitting high bush invasion and
P. incana is more competitive for both soil nutrients and moisture on the soil surface and outcompetes grass growth (Kakembo, 2004).
Ecological changes in Nyaniso rangelands in a transition in species composition from grassland to bush encroachment bear a resemblance to the findings of Kotile (2001) who postulated that
74
bush encroachment and shrub invasion drives the herbaceous composition to unpalatable
species establishment. All the common species found in the current study were perennials.
Table 4.3 Mean (± S.E) abundance of the common grass species in four treatments.
Species RC RWOC G C GWOC Eragrostis capensis 8.2±(2.1)a 5.1±(2.1)a 4.2±(2.1)a 5.1±(2.1)a
Eustachys paspaloides 5.4±(1.2)a 6.4±(1.2)a 2.0±(1.2)b 4.0±(1.2)ab
Themeda triandra 6.9±(1.5)a 2.5±(1.5)b 3.8±(1.5)ab 3.9±(1.5)ab
Microchloa caffra 4.4±(1.0)a 2.6±(1.0)a 3.7±(1.0)a 3.0±(1.0)a
Digitaria eriantha 3.2±(1.0)a 2.8±(1.0)a 2.0±(1.0)a 1.0±(1.0)b
Eragrostis chloromelas 3.5±(1.3)a 2.6±(1.3)a 4.1±(1.3)a 4.6±(1.3)a
Sporobolus africanus 2.7±(1.0)a 1.7±(1.0)a 2.5±(2.2)a 2.2±(2.2)a
Different superscripts across the row represent significant differences (p<0.05).
4.3.4. Effects of treatments on grass heights. Data on grass height were collected during the growing season because it was anticipated that
plant growth is insignificant during the winter season. Eragrostis capensis and Themeda
triandra had significantly the highest plant height in subplots receiving CR and the least in
GWOC treatment. Eustachys paspaloides had significantly the highest plant height in plots
receiving rested and chopped CR, whereas plant height recorded in the other three treatments
were statistically similar. The P. incana invasion is ascribed to have contributed to the lowest
plant height under treatment combination receiving no chopping due to its high competition in
terms of moisture (Kakembo, 2004) whereas resting may have contributed to highest heights
under (CR) treatment due to P. incana removal and grazing exclusion. Water serves as the
75 medium of nutrient transportation in plants therefore its shortage results in reduced plant growth (Scartazza et al., 2001).
The same results were reported under a study conducted on Sagebrush (shrub) invasion control by Davies et al. (2007), Sagebrush was associated with the decrease of herbaceous vegetation resources and also grass height and yield. Shrub (Sagebrush) removal sometimes results in high grass biomass production even though this is not always the case (Kirk et al., 2012).
In comparison of the treatment effect during the two seasons, the mean heights were higher during summer than in winter in both rested plus chopped and rested plus not chopped treatment whereas grazed plus chopped together with grazed plus not chopped showed no significant differences.
76
Table 4.4 Effects of treatments on grass heights in (cm).
Species height Treatment Plant height
Eragrostis capensis RC 15.3±(1.2)a
RWOC 8.0±(0.8)bc
GC 9.3±(0.9)b
GWOC 7.3±(0.5)c
Eustachys paspaloides RC 16± (0.9)a
RWOC 4.7±(0.4)b
GC 5.2±(0.8)b
GWOC 5.0±(0.9)b
Themeda triandra RC 14.8±(0.4)a
RWOC 9.4±(0.4)b
GC 8.9±(0.7)b
GWOC 5.6±(0.4)c
Microchloa caffra RC 9.7±(1.2)a
RWOC 9.7±(1.2)a
GC 8.0±(1.5)a
GWOC 5.0 ±(0.5)a
Values with different letters within a column show significant difference (P < 0.05).
4.3.5 Effects of treatments on grass diameter. Eragrostis capensis, Eustachys paspaloides, Microchloa caffra and Themeda triandra had significantly the highest plant diameters in plots receiving CR. It is suspected in our study that
77
P. incana has advantage over grasses because its presence results in low performance of the grasses. P. incana morphology gives it a competitive advantage (taller height than grasses resulting in shading) hence CR resulted in greater grass yields than the other treatments. It has been reported that P. incana root system can go to as far as 90cm-100cm deep whereas grass roots can go from 40 cm-60 cm deep. This proves the competitive advantage of this shrub over the grasses (Kakembo, 2009). Consequently bush encroachment and shrub invasion have a negative effect on the nutrient, water and light availability on the understory environment
(Scholes and Archer, 1997). Prevosto et al. (2006) agreed that both species quantity and grass cover were reduced following Cytisus scopartius encroachment due to shading or a reduction in light demanding species.
The high amounts of the soil nutrients in the CR treatment more especially the essential nutrients e.g. potassium and phosphorus (Table 4.8) might have resulted in larger or taller heights, diameters. Prevosto et al. (2006) agreed that both species quantity and grass cover were reduced following Cytisus scopartius encroachment due to shading or a reduction in light demanding species.
78
Table 4.5 Effects of treatments on grass diameter (in cm).
Species diameter Treatment Plant diameter
Eragrostis capensis RC 15.33±(1.2)a
RWOC 8.0± (0.8)bc
GC 9.3±(0.9)b
GWOC 7.3±(0.5)c
Eustachys paspaloides RC 7.8±(0.4 )a
RWOC 2.1±(0.1)c
GC 5.5±(0.4)b
GWOC 1.4±(0.5)c
Themeda triandra RC 9.8±(0.3)a
RWOC 5.8±(0.5)bc
GC 5.8±(0.4)b
GWOC 5.6±(0.4)c
Microchloa caffra RC 9.7±(0.6)a
RWOC 5.0±(0.6)ab
GC 4.9±(0.5)b
GWOC 3.3±(0.4)a
Values with different small letters within a column show significant difference (P < 0.05).
GWOC denotes grazed no chopped treat, RC is rested and chopped, RWOC is rested without chopped and GC is grazed and chopped treatment.
79
4.3.6 Effects of treatment on grass yield. Results of grass biomass yield showed that in both dry and wet seasons, plots from CR treatment produced the greatest yield (P<0.05) followed by CG treatment. Reduced competition between P. incana and the herbaceous plants for soil water and nutrients available may have contributed to increase in total herbage production on the CR subplots. P. incana is also known to reduce the grazing capacity of rangelands because soils under P. incana form considerable crusts (Kakembo, 2007) resulting in reduced infiltration and rate of decomposition of the litter and also prevents the emergence of grass seedling. Grazing exclusion in the grasslands leads to a recovery of perennial grass cover that is directly proportional to biomass (Tiedemann and Klemmedson, 2004).
Indeed, exclusion of livestock has been suggested as the main and effective method of maintaining and re-establishing vegetation productivity and diversity in degraded rangelands
(El-Keblawy et al., 2009; Ratherford and Powrie, 2010). The results in our study agree well with the previous findings that reported the removal of woody species on grasslands resulted in increased herbage biomass production (Martin and Morton, 1993; McClaran et al., 2003).
In contradiction, Jimeznez- Labato and Vaverd (2006) reported that grass production was higher under shrub canopies in contrast to open grass areas. Leguminous trees usually result in high grass biomass production and non-leguminous trees result in low grass biomass production under canopies, so this may be the reason of the differences between the current study and the other studies. According to Teague (2009), the minimum state of biomass production for soil protection against degradation is 800kg/ha whereas under livestock production perspective, the minimum threshold for biomass production is 1500 kg/ha.
However none of the treatments has met the minimum threshold for both livestock and degradation perspectives except for resting plus chopping treatment, therefore the invaded
80 rangeland cannot ensure sustainable livestock production in Peddie communal areas not unless control measures are put in place.
Table 4.6 Mean treatment effects on grass biomass production during summer and winter season in kg/ha.
Treatment Summer season Winter Season
GWOC 473Ba 256Ba
RWOC 454Ba 326Ba
GC 564Ba 476Aa
RC 1772Aa 697Ab
S.E 91.53
Lower case superscripts are used to compare means between seasons within each treatment, whereas uppercase superscripts are used to compare treatment means within each season.
Means with different superscripts differ significantly (P<0.05).
4.3.7. Effects of treatments on distance between tufts.
Results of distance between tufts showed that in both dry and wet seasons, subplots from CR treatment had the lowest distance between tufts (P < 0.05) followed by GC treatment. Lowest distance under CR treatment could be ascribed to seedling establishment, increased basal cover during resting period. It is however postulated from the current study that P. incana contributes to bare patches as it has been confirmed to be directly proportional to bare patch development.
In a study conducted by Richardson and Wilgen (2004) grass-tree competition was the main cause of poor rangeland production e.g. bare patch expansion, which consequently plays a vital
81 role in loss of grazing potential. The greater bare area under GC than CR might be due to grazing pressure. Continuous grazing is associated with bare patch development and bush encroachment by Lesoli et al. (2013), therefore the combination of continuous grazing on its own is detrimental to palatable a plant that is why it had largest bare patch.
As for seasons, CR treatments and GC treatments showed seasonal variation for distance between tufts with the summer season having smaller distance than the winter season. It has been postulated from the perceptions under chapter 3 of this thesis that P. incana normally invades the dry areas as a result its density was low along the rivers. Winter season is suspected to have greater threat to bare patch development than summer due to scarcity of water in winter in the rangelands of the Eastern Cape. Grass density reduction and vigor due to heavy grazing always result in percolation of water down to subsoil where shrub roots are mostly found and grasses are few. Grass roots depth showed a significant difference in P. incana roots in a study conducted by (Kakembo, 2009), where by the average number of grass roots decreased more rapidly than P. incana.
Table 4.7 Treatments means on distance between tufts (cm).
Treatment Summer Winter
RC 2.9± (0.4)Db 5.4±(0.3)Ac
RWOC 7.4±(0.6)aB 8.2± (0.3)Aa
GC 4.6±(0.6)bC 6.3±(0.3)aB
GWOC 8.7±(0.7)Aa 8.2±(0.4)Aa
82
Values with different higher cases within a column show significant difference and values with different lower cases within a row show significant difference (P<0.05). Standard error in brackets.
4.3.8 Effects of treatments on soil minerals in Nyaniso communal area.
There were significant variations in soil chemical nutrients among treatments applied in rangeland of Ngqushwa district. Potassium levels were higher (P<0.05) under treatment CR and CG than GWOC and RWOC treatment.
Both soil P and Fe levels were higher (P <0.05) in the CR treatments than the other treatments suggesting that bush clearing combined with resting could improve the nutrient contents of the soil. Grazing exclusion does not only affect forage height and biomass but soil nutrient concentration and availability as well as forage nutrients build up.
The level of soil N was significantly the lowest in the CR treatment than the rest of the treatments and it is suspected that differences could be in the parent materials from which the soils were derived and also low organic matter. Thorpe et al. (2006); Koutika et al. (2011) suggested that low organic matter content due to invasion by exotic plants usually results in low nitrogen and phosphorus concentration.
Solomon et al. (2007) agrees with the results of the current study where they found nitrogen concentration to be directly proportional (where there is no shrub invasion there is low or no nitrogen at all) to the invasion of Chromolaena odorata in Swaziland. In contradiction Yusuf et al. (2013) found low concentrations of N and P in an invaded area than areas lacking Lantana camara were reported. High nitrogen amounts under canopies might be due to nitrogen fixing trees.
83
Under all treatments applied the concentrations of the soil nutrients mentioned above were within the ideal range for plant requirement even though they varied with levels. Total nitrogen deficiency can limit grass productivity (Solomon et al., 2007).
Organic matter accumulation on the sites that have received CR treatment might be due to littering of the leaves. It was suspected from the current study that organic matter on the invaded areas might be lower than open areas as P. incana is associated with soil crusting and low moisture availability (John, 2009). In support of the above idea, Thorpe et al. (2006) reported that organic matter processes are very slow in areas invaded by exotic plants. Thorpe et al. (2006); Koutika et al. (2011) suggested that low organic matter content due to invasion by exotic plants usually results in low nitrogen and phosphorus concentration.
Grazing of the livestock on an area invaded by P. incana might not meet the requirements of the animals more especial high producing animals like pregnant animals, unless the soils are fertile naturally.
Some exotic plant species have an allelopathic advantage of producing secondary complexes from (roots exudes and leaf leachates) that are novel to the native grass and woody species and give them with a head start advantage in resource competition (Callaway and Ridernour, 2004;
Weidenhamer and Collaway, 2010).
84
Table 4. 8 Soil chemical properties between treatments in the rangeland of Nyaniso community.
Soil RC RWOC GC GWOC Critical constituent levels pH (KCI) 4.6±(0.09) a 4.7±(0.09) a 4.7±(0.09) a 4.6±(0.09) a
Ca (Cmol/kg) 2.2±(0.2) a 2.4±(0.2) a 2.3±(0.2) a 2.2±(0.2) a <0.35
Mg (Cmol/kg) 1.7±(0.1)a 1.8±(0.1) a 2.0±(0.1) a 2.0±(0.1) a <0.07
K (Mg/kg) 160±(9.7)a 146±(10.6)b 156±(9.7)a 129±(10.6)c <0.15
P (Mg/kg) 35.4±(4.2)a 22.0±(4.2)b 15.6±(4.2)b 16±(4.2)b <10
Cu (Mg/kg) 1.7±(0.2)a 1.8±(0.2)a 2.0±(0.2)a 2.0±(0.2)a
Zn (Mg/kg) 0.8±(0.09) a 0.8±(0.1) a 0.8±(0.1) a 0.7±(0.1) a
C (%) 1.8±(0.1) a 1.9±(0.1) a 2.0±(0.14) a 1.7±(0.1) a
Fe (Mg/kg) 140.2±(6.2)a 61.8±(6.2)c 81.5±(6.2)b 77.1±(6.9)b
N (%) 0.133±(0.01)b 0.14±(0.01)a 0.15±(0.01)a 0.15±(0.01)a <0.7
Different superscripts across the row represent significant differences (p<0.05).
RC =Rested+ chopped, RWOC= Rested + no chopped, GC = Grazed + chopped, GWOC=
Grazed + not chopped.
4.3.9 Conclusion In as much as the P. incana control treatment is concerned it was concluded that CR treatment had the greatest improvement in grass basal cover as the bare patches got reduced in sizes after the application of CR in relation to GC, GWOC and RWOC treatments. It can be concluded that CR can improve grass height and hence the biomass production under CR treatment was
85 also the greatest while GWOC treatment was very detrimental to biomass production.
Chopping plus resting is the appropriate control method that can be used to minimize the impact of P. incana in the rangelands of Ngqushwa district.
4.4 Recommendation. It is recommended from the current study that fencing of the grazing veld and
application of rotational grazing together with chopping plus resting treatment might
be a sound control measure of P. incana impacts.
Extension of the resting periods to be more than the ones applied in the present study
could increase the effectiveness of the chopping and resting treatment.
In the current study nutrients were only analyzed in the soil samples so it is
recommended that nutrients should be analyzed in both grass and soil as to check if the
nutrient deficiencies are not due to P. incana invasion as they are correlated.
86
Chapter. 5 Summary
5.1 General discussion
The objectives of this study were to assess the farmers’ knowledge and perception of Pteronia incana invasion and impacts on livestock production and peoples’ livelihoods in four communal areas, and to investigate the impacts of P. incana invasion and control methods on the herbage biomass production, species distribution and soil characteristics in Nyaniso rangeland at Ngqushwa district. In Chapter three, 80 farmers were selected from four communal areas, from each communal area, twenty households that own livestock were randomly selected to conduct an interview using an open and closed ended questionnaire.
The results under livestock population showed that goats had the highest mean household holding number than any other livestock species across the selected villages. This could be ascribed to the fact that goats have higher resistance to drought than other livestock species, because they browse and have a faster breeding cycle (Libala, 2015). Similar results were reported by Mndela (2013). Three out of four villages raised cattle primarily for income generation and secondarily for cultural purposes like slaughtering during weddings ceremonies, amazila and also during woman circumcisions (Ntonjane). Similarly, goats and sheep are primarily raised for cash income generation. The respondents revealed that livestock population decreased over 10-20 years ago as most famers assumed to be due to poor rangeland conditions as feed is the key factor for production and most farmers do not supplement their animals. It was postulated that P. incana is indigenous to the study site even though its density was lower than the current situation in the past twenty years. Climate change could be associated with an increase of the invasion. Forage and animal performance as well as farmer’s livelihoods were reported to be negatively affected by P. incana invasion due to its high competition to forage growing next to it. Respondents revealed a shift of perennial grass species
87 to annuals resulting to low biomass next to the encroachment. In chapter 4, respondents recommended control methods of P. incana to improve rangeland grass and animal production.
With regard to the grass species distribution under the applied treatment, only Eragrostis capensis that was common in the CR and RWOC treatment in summer season than winter. This could mean that this species favored grazing exclusion and growing on open areas even though most of grass species were not affected significantly. Grass biomass production was the greatest under CR treatment. Consequently, reduced competition between P. incana and the herbaceous plants for soil water and available nutrients may have contributed to increase in total, grass height and diameter as a result herbage production on the CR subplots was consequently increased. However none of the treatments has met the minimum threshold for both livestock and degradation perspectives except for resting plus chopping treatment, therefore the invasion by P. incana and continuous grazing is detrimental to agriculture. Similar results were reported by Tiedemann and Klemmedson (2004) that grazing exclusion in the grasslands leads to a recovery of perennial grass cover that is directly proportional to biomass.
In as much as soil nutrients are concern, P and Fe levels showed higher concentration (P< 0.05) in the CR treatments than the other treatments suggesting that bush clearing combined with resting could improve the nutrient contents of the soil.
5.2 Conclusion
In as much as the farmers’ perceptions were concern it was concluded that respondents were partly informed about the effects of P. incana invasion and their livelihoods in agriculture. The density of P. incana significantly multiplied as years went by and risks of livelihoods of farmers became endangered concurrently. P. incana invasion has detrimental effects on rangelands of the study area and consequently in livestock production and species diversification as small stock predation by jackals were promoted by P. incana invasion as they
88 hide on the shrub, therefore it is concluded that P. incana invasion reduces the choices of farmers to different food products, income, savings and security more especially during drought periods. However, the livelihoods of the respondents were affected by P. incana invasion as most of them seem to be unemployed. As far as the P. incana control methods were concern chopping plus resting RC treatment was the appropriate method that can be used to minimize the impact of P. incana in the rangelands of Ngqushwa district as it has resulted in better grass production.
89
References Abdallah, F., Noumi, Z., Ouled-belgacem, A., Michalet, R., Touzard, B., and Chaieb, M., 2012.
The influence of Acacia tortilis (Forssk) ssp. raddiana (savi) Brenan presence, grazing,
and water availability along the growing season, on the understory herbaceous
vegetation in Southern Tunisia. Journal of Arid Environments, 76: 105 114.
ALASA, 1998. Handbook of feeds and plant analysis. Palic, D. (Ed).
Annika, A., 2012. Towards a Transcultural Community of Climate Change. Adapting Max
Weber`s Distinction of Vergemeinschaftung and Vergesellschaftung. In: Maik Arnold
Przemyslaw Lukasik (eds.): Europe and America in the Mirror: Culture, Economy, and
History. Kraków: Nomos.
Axmann, B.D., and Knapp, A.K., 1993. Water relations of Juniperus virginiana and
Andropogon gerardii in an unburned tall grass Prairie watershed. The South Western.
Naturalist, 38: 325-330.
Bekele, A., Hudnall, W.H., and Downer, R. G., 2006. Woody encroachment effects on the
calcareous soil. Journal of Geophysical research, 111. DOI: 10.1029/2006JG000214.
Bremner, J.M., and Breitenbeck, G.A., 1983. A simple method for determination of ammonium
in semi–micro Kjedahl analysis of soil and plant material using a block digester.
Communications in Soil Science and Plant Analysis, 14: 905–913.
Callaway, R.M., and Ridenour, W.M., 2004. Novel weapons: Invasive success and the
evolution of increased competitive ability. Frontiers in Ecology and the Environment,
2: 436-443.
Creel, S., and J. A., and Winnie, Jr., 2005. Responses of elk herd size to fine-scale spatial and
temporal variation in the risk of predation by wolves. Animal Behaviour, 69: 1181–
1189.
90
Davies, K.W., Bates, J. D., and Miller, R.F., 2007. Short-term effects of burning Wyoming big
sagebrush steppe in southeastern Oregon. Rangeland Ecology and Management, 60:
515–522.
Eldridge, DJ, Maestre FT, Moro, S, and Bowker MA., 2011. A global database of woody
encroachment effects on ecosystem structure and functioning. Ecology, 93: 2499.
El-Keblawy, A., Ksiksi, T., and El-Alqamy, H., 2009. Camel grazing affects species diversity
and community structure in the deserts of the UAE. Journal of Arid Environment, 73:
347–354.
Graff, P., Aguiar, M.R., and Chaneton, E.J., 2007. Shifts in positive and negative plant
interactions along a grazing intensity gradients. Ecology, 88: 188–199.
Jimenez-labato and Veverde, T., 2006. Population dynamic of the shrubs acacia bilimekii in a
semi desert region in central Mexico. Journal of arid environment, 65: 29-45.
John, O.O., 2009.The invasion of Pteronia incana (blue bush) along a range of gradient in the
Eastern Cape Province: Its spectral characteristics and implications for soil moisture
flux. PhD. Thesis. Nelson Mandela Metropolitan University. Port Elizabeth, South
Africa.
Kakembo, V., 2004. Factors affecting the invasion of Pteronia incana (Blue bush) onto
hillslope in Ngqushwa (formerly Peddie) District, Eastern Cape, PhD thesis, Rhodes
University, Grahams town.
Kakembo, V., 2009. Vegetation patchiness and implications for landscape function: the case
of Pteronia incana invader species in Ngqushwa Rural Municipality, Eastern Cape,
South Africa. Catena, 77: 180–186.
91
Kakembo, V., Rown tree, K.M., and Palmer, A.R., 2007. Topographic controls on the invasion
of Pteronia incana (Blue bush) onto hill-slopes in Ngqushwa (formerly Peddie)
District, Eastern Cape. Catena, 70: 185–199.
Kirk, W., Davies, Jonathan, Bates, D., and Aleta, M., 2012. Mowing Wyoming Big Sagebrush
communities With Degraded Herbaceous Understories in Oregon State University,
Corvallis: Has a Threshold been crossed? Rangeland Ecology and management, 499.
Koutika, LS., Rainey, H.J., and Dassonville, N., 2011. Impacts of Solidago gigantean,
Prunusserotina, Heracleummantegazzianun and Fallopiajavanica invasion on
ecosytems. Applied Ecology of environment research, 9: 73-83.
Kunkel, K.E., and Pletscher, D.H., 2000. Habitat factors affecting vulnerability of moose to
predation by wolves in south eastern British Columbia. Canadian Journal of Zoology,
78: 150–157.
Lesoli, M.S. Gxasheka, M., and Solomon, T.B., 2013. Integrated Plant Invasion and Bush
Encroachment Management on Southern African Rangelands. South Africa, 262-277.
Linneman, J.S., and Palmer, M.W., 2006. The effect of Juniperus virginiana on plant species
composition in an Oklahoma grassland. Community Ecology, 7: 235- 244.
Martin, S.C., and Morton, H.L., 1993. Mesquite control increases grass density and reduces
soil loss in southern Arizona. Journal of Range Management, 46: 170–175.
McClaran, M.P., 2003. A century of vegetation change on the Santa Rita Experimental Range.
In: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station,
16-33.
McClaran, M.P., Ffolliott, P. F., Edminster, C.B., and tech. coords., 2003. Santa Rita
Experimental Range: one-hundred years of accomplishments and contributions. Proc.
92
RMRS-P-30. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky
Mountain Research Station, 16–33.
Mugasi, S.K., Sabiiti, E.N., and Tayebwa, B.M., 2000. The economic implications of bush
encroachment on livestock farming in rangelands of Uganda. African Journal of Range
and Forage Science, 17: 64 – 69.
O’Farrell, P.J., Le Maitre, D., Gelderblom, C., Bonora, D., Hoffman, T., and Reyers, B., 2007.
Applying a resilience framework in the pursuit of sustainable land-use development in
the Little Karoo, South Africa, in: M. Burns and A. Weaver (Eds), Advancing
sustainability science in South Africa. (Stellenbosch, South Africa, African SUN
MeDIA).
Oba, G., and Kotile, D.G., 2001. Assessment of landscape level degradation in Southern
Ethiopia. Pastoralists versus ecologists. Land Degradation and Development, 12: 46–
475.
Palgrave, M.C., 2002. Trees of South Africa. Struik Publishers, Cape Town, South Africa.
Prévosto, B., Dambrine, E., Coquillard, P., and Robert, A., 2006. Broom (Cytisus scoparius)
colonization after grazing abandonment in the French Massif Central: impact on
vegetation composition and resource availability. Acta Oecologica, 30: 258- 268.
Ratherford, M.C., and Powrie, L.W., 2010. Severely degraded rangeland: implications for plant
diversity from a case study in Succulent Karoo, South Africa severely degraded
rangeland: implications for plant diversity from a case study in Succulent Karoo, South
Africa. Journal of Arid Environment, 74: 692–701.
Richardson, D.M., and Van Wilgen, B.W., 2004. Invasive alien plants in South Africa: How
well do we understand the ecological impacts? South African Journal of Science, 100:
45-52.
93
Riginos, C., and Grace, J.B., 2008. Savanna tree density, herbivores, and the herbaceous
community: Bottom-up vs. Top-down effects. Ecology, 89: 228 – 2238.
Robson, A.D., 1995. The Effects of Grazing Exclusion and Blade-Ploughing on Semi-Arid
Woodland Vegetation in North-Western New South Wales Over 30 Months. The
rangeland Journal, 17: 111-127.
Scartazza, A., Proietti, S., Moscatello, S., Augusti, A., Monteverdi, M.C., Brugnoli, E., and
Battistelli, A., 2001. Effect of water shortage on photosynthesis, growth and storage
carbohydrate accumulation walnut (JUGLANS REGIA L.). Act Hortic. 544: 227-
232.htt://dx .doi17660/ActHortic. 2001.544.30
Scholes, R.J., and Archer, S.R. 1997.Tree-grass interactions in savannas. Annual Review of
Ecology and Systematics, 28: 517–544.
Soliveres, S., Eldridge, D.J., Maestre, F.T., Bowker, M.A., Tighe, M. And Escudero, A., 2011.
Microhabitat amelioration and reduced competition among understory plants as drivers
of facilitation across environmental gradients: Towards a unifying framework.
Perspectives in Plant Ecology, Evolution and Systematic (2011).
http://dx.doi.org/10.1016/j.ppees.2011.06.001.
Solomon, T.B., and Mlambo, V., 2010. Encroachment of Acacia brevispica and Acacia
drepanolobiumin Semi-Arid rangelands of Ethiopia and their influence on sub-canopy
grasses. Research Journal of Botany, 5: 1 – 13.
Solomon, T.B., Snyman, H.A., and Smit, G.N., 2007. Rangeland dynamics in Southern
Ethiopia: (3). Assessment of rangeland condition in relation to land-use and distance
from water in semi-aridBorana rangelands. Journal of Environmental Management, 85:
429 – 442.
94
Solomon, T.B., Dlamini, B.J., and Dlamini, A.M., 2008. Invasion of Chromolaena odorata in
the Lowveld Region of Swaziland and its Effect on Herbaceous Layer Productivity,
Swaziland. International Journal of Agricultural research, 3: 105-106.
Teague, W.R., Kreuter, U.P., Grant, W.E., Diaz-solis, H., and Kothmann, M.M., 2009.
Economic implications of maintaining rangeland ecosystem health in a semi-arid
savanna. Ecological Economics, 68: 1417 – 1429.
Tennesen, M., 2008. When juniper and woody plants invade, Water May Retreat. Sci, 322:
1630-1931.
Thorpe, A.S., Archer, V. and Deluca, T.H., 2006. The invasion forb centaureamaculosa
increases phosphorus availability in Montana grass lands. Applied Soil Ecology, 32:
118-122.
Tiedemann, A.R., Klemmedson, J.O., 2004. Responses of desert grassland vegetation to
mesquite removal and regrowth. Journal of Range Management, 57: 455-465.
Van Auken, O.W., 2009. Causes and consequences of woody plant encroachment into western
North American grasslands. Journal of Environmental Management, 90: 2931–2942.
Van Oudtshoorn, F., 2012. Guide to Grasses of southern Africa. Cape Town, South Africa, 96.
Warburton, D., 2011. Rangeland condition monitoring: A guide for pastoral lessees. www.
agric.wa.gov.au. Accesssed [12-06-2015].
Ward, D., 2005. Do we understand the causes of bush encroachment in African savannas?
African Journal of Range and Forage Science, 22: 101−105.
Weidenhamer, J.D., and Colloway, R.M., 2010. Direct and indirect effects of invasion plants
on soil chemistry and ecosystem function. Journal of Chemical Ecology, 36: 59-60.
95
Yusurf, R., Simba. Abel, M., Kamweya, Peter, N., Mwangi and John, M. Ochora., 2013. Impact
of invasive shrub, Lantana camara on soil properties in Nairobi National park, Kenya,
International Journal of Biodiversity and conservation, 5: 807-808.
96
Appendix 1: Questionnaire
Effects of Pteronia incana (Blue bush) invasion on peoples’ livelihoods in Ngqushwa
communal rangelands, Eastern Cape.
The objective of the survey is to investigate the farmers’ knowledge and perception of
Pteronia incana invasion and its impacts on livelihoods in four communal areas of Ngqushwa,
Eastern Cape.
Enumerators name…………………………………………………………Date……………… Village………………………………………………………………………………………….. Name of respondent…………………………………..Questionnaire reference number……… INSTRUCTIONS: Fill in the relevant information and where possible mark with an X
A.HOUSEHOLD DEMOGRAPHY Relation to head: 1 Head…………2 Spouse /husband……….3 Child………. 4 Grandchild….5 Father or mother….. 6 other….. Marital status: (S) Single…….. (M) Married……….. (D) Divorced or separate……….(W) Widow………….. Education: 1 Preschool ……….2 Up to std 5……...3 Std 6-9………4 Std 10……...5 Tertiary………. 6 None…….. Age of the household head: …………………………………………………………………….
Status: (1) farming…………. (2) Household wife……….(3) Employee……….. (4) Pensioner……… (5) Business…………. (6) No occupation………….. (7) Student……….
Household size…………… Adults …………… Children (less than 13 years)……..
97
B.1 Livestock statistics in the village and Pasture production. Livestock type Livestock statistics Age group Sheep 2yrs < 2yrs 2yrs > Total Male Female Age group Goat 2yrs < 2 yrs 2 yrs> Total Male Female Age group Cattle 3 yrs < 3 yrs 3 yrs> Total
B.1. Importance of livestock species (ranking in order of importance 1-most important, 3-least important) Class Cattle Sheep Goat Rank
B.2.1.Purpose of rearing livestock (ranking in order of importance 1-most important, 5-least important) Purposes Sale Dowry/Lobola Prestige Food Draft Other (Meat& power ( specify) milk) Rank B.2.2 Purposes Sale Traditional Prestige Other purposes ( specify) Rank
B.2.3 Purposes Sale Prestige Wool Food Other production (Meat& ( specify) milk) Rank
B.3.Crop farming B.3.1. What are your crop commodities (from most important to least important?) Crop type
98
1) 2) 3) 4)
B.4.Do you feed crop residues to livestock? Crop type Livestock(Goat=1,Sheep=2,Cattle=3) Time (season) 1) 2) 3) 4)
B.5.1.Do you have demarcated/ fenced natural grazing land? Yes or no B.5.2.If the answer is yes in B.5.1, is the demarcated area continuously grazed or grazed during winter, spring, summer, autumn season or grazing ...... B.5.3. Is it communal owned or private? B.5.4.what is the size of the area
B.6.1Do you have cultivated pasture? ………………………………………………………………………………………………... B.6.2.If yes, name the species in there………………………………………………………..... …………………………………………………………………………………………………. B.6.3Do you have irrigation system/ access to water? ………………………………………………………………………………………………… B.7.Which landscapes are normally preferred for grazing by livestock? Put a tick to the relevant answer. B.8.Mountain top plain……., Steep slope…... gentle slope…... river banks….., flat slopes……., other……. B.9. How is the condition of the mostly preferred grazing areas? …………………………………………………………………………………………………. B.10.which problems do you face in management of grazing areas? …………………………………………………………………………………………………
…………………………………………………………………………………………………
B.11.How was the condition of the rangeland days before (10-20 years back)?
99
…………………………………………………………………………………………………
…………………………………………………………………………………………………
…………………………….
B.12.Do you assess the rangeland condition?
………………………………………………………………………………………………….
B.13. If yes inB.12. Which systems do you use to asses rangelands?
………………………………………………………………………………………………….
C. Rangelands / Grazing C.1. Do you utilize rangelands for grazing? Yes No C.2.At what time of the year would you experience a shortage in grazing? (Winter, summer, autumn, spring)-specify the month. ………………………………………………………………………………………………….. C.4.What could be the cause of such a shortage? 1)……………………………………………………………………………………………...... 2)………………………………………………………………………………………………... 3)………………………………………………………………………………………………... C.5. Who monitors that users of the grazing land adhere to rules and regulations? ...... C.6. Rangeland is used for? (In order of importance: 1-most important 5-least important) Uses Rank Season of access(summer, winter, year round) Grazing/browsing of animals
Collecting fire wood
Collecting wood and grass for building and Fencing
Collecting plants for medicinal purposes
Collecting dry dung for cooking
Other (specify) ………………………………………………
100
C.7.1. Are there times of restricted access to rangelands? Yes
No C.7.2.If Yes, Which month(s)………………………………………......
C.8. Does your community have grazing camps? Yes No C.8.1. If yes, what is the purpose of camps? (Give answer in order of importance) ………………………………………………………………………………………………… ………………………………………………………………………………………………… C.9 Mention the situation of grazing during the following seasons.
Season Good Moderate Fair Poor Summer Winter
D Livestock Production
D.1. what threat do the neighbouring communities put on your rangeland
D.2 For how long do you keep your livestock on the fields utilising the residues or st?
D.3 What impact does your answer in no.3 has on the fields………………………………….?
D.4 Do women work together with men on livestock production…………...... ?
D.5.A Does youth take part in agricultural practises...... ?
D.7. Do you use any breeding management system
…………………………………………………………………………………………….?
D. 8 What is the major constraints that you face on animal production?
………......
……………………………………………………………………………………………..
D.8 In which season of the year do you notice the challenge…………...... ?
101
D.9. where do you Near Middle Far graze, how far from your homestead?
D.10. How often do you collect livestock from the range?
…………………………………………………………………………………………
E.1. How is the condition of the grazing land currently?
Condition Mark Very poor Poor Fair Good Very good I don’t know
E.2. what resulted to the condition of the range mentioned above, rank according to the importance (rom the most to the list)
Reason Rank Stocking rate applied Type of animals utilising the rangeland Climate Absence of fire/ incorrect use of fire Shrub invasion Topography Other(specify)
Ranks (1)……(2)…...(3)…… (4)…….(5)…….(6)……(7)
E.3.How can the University of Fort Hare help you to minimise the problem?
…………………………………………………………………………………………………..
…………………………………………………………………………………………………..
102
………………………………………………………………………………………………......
F. Pteronia incana invasion and land degradation
F.1.When did P.incana get into the community??
…………………………………………………………………………………………………..
F.2. How is the density of P. incana in the rangeland?
Density Mark
Very high
High
Average
Low
None
F.3. which are the most invaded areas?
…………………………………………………………………………………………………
…………………………………………………………………………………………………
F.4. Do you apply any control measure on the invaded land?
Put tick to the relevant answer
Yes……No…..
F.5. If yes which methods do you use to control P.incana.
F. 6 Is the method effective??
Yes….. No…….
103
F.7 Support your answer above………………………………………………………………..
F.8.Does the invasion affects livestock production?
Yes….. No…….
How……………………………………………………………………………………………
…………………
F.9. What are the uses or the benefits of Pteronia incana species?
Use of P.incana No. of respondents % of respondents
Biomass fuel
Fencing/ livestock enclosure
Medicinal
Packing for erosion gullies
Do not use
Other (specify)
How do you consider the condition of your soil?
Good Fair Poor Very poor Don’t know
C.10. What is the reason for your answer above?
………………………………………………………………………………………………
C.11. what are the major causes of invasion in the rangeland?
Start with the most important to least important (1-6)
104
Reason Mark
Overgrazing
Climate change
Drought
Infrequent or absence of burning
Expansion of settlements on grazing lands
Uncontrolled livestock movement
I do not know
C.12 what are the effects of P. incana invasion on rangeland, crop production and Livestock?
Rangelands...... Crop...... Livestock......
C.13. How does the invasion affect your livelihoods......
......
C.14. Any other comments about the Pteronia incana invasion......
105
Appendix 2: Ethical clearance certificate.
106
Appendix 3: Biomass ANOVA tables for both summer and winter.
Source DF Type I SS Mean Square F Value Pr > F trt 3 12137145.24 4045715.08 40.24 <.0001 Seasons 1 3415753. 54 3415753.54 33.98 <.0001 trt*seasons 3 3954201.36 1318067.12 13.11 <.0001
Source DF Type III SS Mean Square F Value Pr > F trt 3 12137145.24 4045715.08 40.24 <.0001 Seasons 1 3415753.54 3415753.54 33.98 <.0001 trt*seasons 3 3954201.36 1318067.12 13.11 <.0001
Appendix 4: Soil mineral ANOVA tables
Dependent Variable: pH
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.07791667 0.02597222 0.54 0.6591
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.07791667 0.02597222 0.54 0.6591
Dependent Variable: Ca
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.12191667 0.04063889 0.23 0.8726
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.12191667 0.04063889 0.23 0.8726
Dependent Variable: Mg
Source DF Type I SS Mean Square F Value Pr > F Sites 3 3219.106946 1073.035649 1.00 0.4134
107
Source DF Type III SS Mean Square F Value Pr > F Sites 3 3219.106946 1073.035649 1.00 0.413
Dependent Variable: K
Source DF Type I SS Mean Square F Value Pr > F Sites 3 7932.000000 2644.000000 1.03 0.3996
Source DF Type III SS Mean Square F Value Pr > F Sites 3 7932.000000 2644.000000 1.03 0.3996
Dependent Variable: P
Source DF Type I SS Mean Square F Value Pr > F Sites 3 475.4583333 158.4861111 0.63 0.6048
Source DF Type III SS Mean Square F Value Pr > F Sites 3 475.4583333 158.4861111 0.63 0.6048
Dependent Variable: Cu
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.23614583 0.07871528 0.39 0.7625
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.23614583 0.07871528 0.39 0.7625
Dependent Variable: Zn
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.09041250 0.03013750 0.53 0.6640
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.09041250 0.03013750 0.53 0.6640
Dependent Variable: C
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.35783333 0.11927778 0.93 0.4441
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.35783333 0.11927778 0.93 0.4441
Dependent Variable: Fe
108
Source DF Type I SS Mean Square F Value Pr > F Sites 3 5261.454433 1753.818144 1.10 0.3741
Source DF Type III SS Mean Square F Value Pr > F Sites 3 5261.454433 1753.818144 1.10 0.3741
Dependent Variable: N
Source DF Type I SS Mean Square F Value Pr > F Sites 3 0.00116667 0.00038889 1.75 0.1883
Source DF Type III SS Mean Square F Value Pr > F Sites 3 0.00116667 0.00038889 1.75 0.1883
109