Physicochemical Properties of Soil Analysis Under Rangeland Traditional Management Practice on Shilavo District, Somali Regional State, East Ethiopia

Journal of Agriculture and Ecology Research International

21(2): 22-30, 2020; Article no.JAERI.53937 ISSN: 2394-1073

Physicochemical Properties of Soil Analysis under Rangeland Traditional Management Practice on Shilavo District, Somali Regional State, East Ethiopia

Mowlid Hassan1,2*, Zawde Tadesse3, Mohamed Abdikader3 and Dinow Sharif4

1Department of Animal Production and Technology, Kebridehar University, Kebridehar, P.O. Box 250, Ethiopia. 2Department of Rural Development and Agricultural Innovation Communication, Jigjiga University. P.O. Box 1020, Ethiopia. 3Department of Natural Resource and Management, Kebridehar University, Kebridehar, P.O. Box 250, Ethiopia. 4Department of Rural Development and Agricultural Extension, Kebridehar University, Kebridehar, P.O. Box 250, Ethiopia.

Authors’ contributions

This work was carried out in collaboration among all authors. Author MH designed the study, technical writing and wrote the first draft of the manuscript. Authors ZT and MA managed the analyses of the study, performed the statistical analysis and wrote the protocol. Author DS managed the literature searches. All authors read and approved the final manuscript.

Article Information

DOI: 10.9734/JAERI/2020/v21i230129 Editor(s): (1) Dr. Nhamo Nhamo, Zimbabwe Open University, Zimbabwe. Reviewers: (1) Fábio Henrique Portella Corrêa de Oliveira, Universidade Federal Rural de Pernambuco, Brazil. (2) Kholil, Sahid University, Jakarta, Indonesia. Complete Peer review History: http://www.sdiarticle4.com/review-history/53937

Received 02 December 2019 Accepted 07 February 2020 Original Research Article Published 27 March 2020

ABSTRACT

Traditional management practice is emerging as one of the strategies to rehabilitate and restore degraded soils. In this study the important roles of area enclosure with comparison to an open sites were investigated for physicochemical properties of soil in rangeland of Shilabo district Somali region, east Ethiopia. The management types (5 yrs enclosures, 10 yrs enclosure and open grazing land) were taken as treatments. The sand, silt and clay content of CGL, 5E and 10E were

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*Corresponding author: E-mail: [email protected];

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78, 76 and 75%; 8.67, 12.00 and 14.67% and 14.67, 10.33 and 10.33% respectively. Where the mean value of N, P and K for CGL, 5E and 10E were 0.04, 0.14 and 0.16%; 3.72, 3.91 and 5.96 mg/L and 0.16, 1.05 and 1.53 (cmol (+)/Kg soil respectively. The soil variable results revealed that soil organic matter, CECs, exchangeable Cat ions and soil moisture were significantly improved as a result of the enclosure. This study generally shows that area enclosure is a promising strategy to rehabilitate degraded environments as it is fast, cheap and lenient.

Keywords: Degraded soils; physicochemical properties; soil organic matter; soil moisture; Shilavo.

1. INTRODUCTION subsequently land degradation. Mureithi et al. [5] it been mentioned that withdrawal of Traditional management practice is emerging as livestock grazing is often not sufficient to one of the cheap strategies to rehabilitate and initiate the autogenic recovery of soil. restore degraded soils in the rangeland areas. Which so important the sustaining soil Rangelands represent about 70% of worldwide condition. rummage for both household and wild creatures. Rangelands spread about 62% of the all out The influence of livestock grazing on plant landmass of the global. Roughly 12-15 million diversity, physicochemical properties of soil peaceful and agro pastoral networks are decline are the major problem in many parts of supported in seven regional conditions of the Somali region rangeland and particularly world. The majority of these areas have been communal grazing land is very common that subjected to loss of nutrients and biodiversity leads very serious soil in soil condition (3). For changes, soil organic matter and land this concept it clear that soil in somali region is in deterioration due to vegetation removal by danger of becoming seriously degrading owing to livestock burning, and climate variability (Belay, natural and human-induced factors. They are 2015). The Somali Regional State is a major under pressure by various drivers of change and pastoral habitat in Ethiopia. It has a total land there are considerable difficulties in assessing area is around 327,000 km2 of which about 90% these changes and what they may mean for is classified as rangeland [1]. The populations in human use of rangeland resources. Heavy Somali region greatly depend on natural forest grazing pressure and climatic factor such as resources for their basic livelihood in many elevation can influence soil erosion and forms. However, the rangeland bio-physical rangeland degradation, increase bush density. conditions such as vegetation cover, soil fertility, Such changes would influence the productivity feed mass production and plant bio-diversity are [3]. Sustainable utilization and management of degrading at an alarming rate, resulting in rangelands ecosystem in the area. In view of deteriorations in the range-livestock production the increasing adoption of rangeland systems and the pastoral livelihoods in the region enclosure and the pressure exerted on the [1]. remaining communal grazing areas, it is important to understand rangeland traditional Because of different interactions among various practice effectiveness in restoring declined of soil biological, environmental and social factors, the property [4]. Despite the obvious rising issues of rangeland management is difficult [2]. Pei et al. private grazing, enclosures within the communal [3] screened that numerous studies have and consequent physicochemical of soil indicated that the overgrazing of rangeland resulting ecological implications for rangeland causes a decline in quality of bio- resource and there have not been studies physicochemical properties results in dramatic considered or investigated how the enclosure changes in vegetation and modifications in has impacts on soil parameters in the rangeland nutrient cycling; indeed, it could lead in the of shilavo district. permanent degradation of land productivity and the ecosystem destruction. Raiesi and Riahi [4] The study was to analyze physicochemical stated that the effects of animal grazing on soil properties of soil in Rangeland of Shilavo District such quality as physicochemical and and to determine the changes brings on selected microbiological properties of soil have been physical and chemical property of soils under reported in many rangeland ecosystems ethiopia area enclosures (traditional practice of and in most cases, rangeland over or continuous rangeland) in comparison with the adjoining grazing resulted in severe soil erosion and communal gazing land.

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2. MATERIALS AND METHODS

2.1 Description of the Study Area

Shilavo (Somali: Shilaabo) is one of the districts in Korahe zone of the Somali Regional state of Ethiopia. Part of the Korahe Zone, Shilabo is bordered on the southwest by the Gode Zone, on the west by Debeweyin, on the northwest by Kebri Dahar, on the northeast by the Werder Zone, and on the southeast by Somalia. The major settlement in Shilavo is Shilavo. The major somali group's inhabited ogaden Bahgeri and makaahil mousagomcadle clan, The woreda Shilavo is the place where found the natural gas of the Ogaden region. Based on the 2007 Census conducted by the Central Statistical Agency of Ethiopia (CSA), this district has a total population of 107,590, of whom 67,376 are men and 34,214 women. While 4,924 or 8.55% are urban inhabitants, a further 36,969 or 64.19% are pastoralists. 98.8% of the population said they were Muslim.

Fig. 1. Study area map

2.2 Experimental Materials and Design were taken as treatments. The sampling sites for both enclosures and open rangelands Different materials were used in the experiment. were selected purposely due to the These materials are Meter, spade, sack, auger, accessibility located at 22 x 22 m and polythene bags, rope, and meter. The categorized into three blocks (6 x 20 m each) experiment was conducted in MAY, 2019 at based on vegetation cover. Top plant Shilabo enclosures and open rangelands with an debris was removed at 1-10 cm depth 2 area of 484 m and relative location of 6°6`N and by using sharp knife. Three transects were 44°46`E. Each management type was farther laid at each block and five samples (4 laid out in to three blocks (Block one (B1), Block samples at corners and 1 sample at the center) two (B2) and Block three (B3) based on was taken and composite as 1 sample. vegetation cover. The field would be designed in Accordingly, from each management type, a randomized complete block design, for three composite samples were taken by using management types as random block and auger at 5 m intervals with 10-20 cm depth. Sampling Site as a fixed effect. Finally, 500 g of 9 composite soil samples (3

2.3 Soil Sampling blocks x 1 composite sample x 3 management types) were prepared, labeled, sealed and The management types (5 yrs enclosures, transported to Haramaya University soil 10 yrs enclosure and open grazing land) laboratory for analysis.

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2.4 Soil Data Collection Procedure

Selected physical and chemical parameters of soil samples such as Total nitrogen, Available phosphorus, Available Potassium (AV.K), Exchangeable Calcium (Ca2+), Exchangeable Magnesium (Mg2+), Power of Hydrogen (pH), Organic Carbon (OC) and OM can be calculated by using conversion factor of 1.724 (OM=1.724*OC), Cat ion Exchange Capacity (CEC), Moisture Content (MC), electrical conductivity (EC) and soil texture will be obtained from Haramaya University Soil Laboratory.

Fig. 2. Soil sampling design

Fig. 3. Taking soil sample using augur inside of enclosure

Moisture contents were determined by Soil texture was determined by using Bouyoucos gravimetric method [6]. Electrical Hydrometer method [9] and Total nitrogen was conductivity was measured on the calibrated EC determined by Kjeldahl digestion method [10]. K, meter and set temperature Compensation Ca, Mg and Na were extracted by using to 25°C, the cell is inserted dip to the extract and Mehlich-3 extraction method [11,12]. Available conductivity is recorded. Therefore, phosphorus was determined by Olsen et al. [13]. Electrical conductivity is recorded at ES ISO 11265:2014 (1:5). Power of Hydrogen was 2.5 Soil Data Analysis measured potentiometrically in the supernatant suspension of 1:2.5 soil distilled water/ kcl Raw Data were subjected to one way analysis of mixture using A3-point calibrated PH-meter while variance (ANOVA) by using general linear model organic carbon was determined by using walkely (GLM) of the SAS statistical package version 9.0 and black method [7]. Cat ion exchange capacity [14] followed by SAS Institute, [14] to determine was determined by using Ammonium acetate the existence of any statistical difference among method [8]. the treatments. Tukey multiple comparisons were

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used to test significant differences among the organic matter, the trampling effect of livestock means Separations of significant and the sparse vegetation aggravate soil erosion differences between and among treatment which selectively removes clay from the open means were done by using least grazing land. The higher clay content in the significant difference (LSD) at 5% probability enclosures means that there is relatively low soil level [15]. erosion in the site, while the lower clay in the open grazing land means there is relatively 3. RESULTS AND DISCUSSION higher soil erosion at the open grazing land, which might reflect the differences in their 3.1 Physicochemical Properties of Soil vegetation cover. The presence of good vegetation cover in the area enclosure reduced Soil texture: Texture of soil samples for the erosion through addition of organic matter and closures and open grazing land was generally surface litter. classified as Sand, silt and clay respectively Primary macronutrients: The total nitrogen in (Table 1). The sand fraction values were CGL was less than that of the enclosures. statistically significant ((P=0.028) for the three Results of this enquiry are in line with the treatments. The mean percentages of sand for findings Yimer et al. [18], who reported the treatments stand at 78, 76 and 75% for open that the higher total nitrogen content in the grazing land, Enclosure1 and Enclosure 2 enclosures is the result of higher soil organic respectively (Table 1). matter content and the presence of leguminous

plants which have the capacity to fix Table 1. Soil texture nitrogen from the atmosphere through the roots’

nodules. Trts Sand (%) Silt (%) Clay (%) b a b CGL 78.0±1.0 14.7±1.2 10.3±0.6 The mean values of Total nitrogen content for 5E 76.0±76.0a 8.7±1.0b 14.7±0.6a open grazing land, 5E and 10E were 0.0, 0.1 and 10E 75.0±3.0a 12.0±2.3 ab 14.7±1.5a 0.2% respectively. The total nitrogen was P 0.028 0.011 0.003 significantly different (<0.0001) for the three Note: Trt: Treatment, CGL: Communal grazing treatments (CGL, 5E and 10E) (Table 2). This land, 10E: Area enclosed ten years, 5E: Area finding is in agreement with work done by other enclosed five years researchers. According to the study by Abiy Tsetargachew [19], there was significant The amount of sand under open grazing land difference on total nitrogen between open was greater than the enclosures. This is probably grazing land and enclosures. The significant due to the systematic removal of clay particles difference on total nitrogen in the free that leaving the sand particles in the free pasture grazing land and the enclosure is due to land [16]. difference in soil organic content and intensities of soil erosion. Under scattered vegetation covers the clay fractions of clay likely to be lost to processes of The mean values of available Phosphorous erosion and migration down the soil profile values for CGL, 5E and 10E were 3.7, 3.9 and [17].The mean percentage of silt under open 6.0 (mg/L), respectively. The mean value of grazing land was greater than that of the available Phosphorous for the free grazing land enclosures. The ANOVA showed that is higher than that of the enclosure but difference statistically, there was significant difference (p = was statistically insignificant (P=0.275) (Table 2). 0.011) on the silt fraction between the CGL, 5E The low available Phosphorous in the enclosure and 10E. This is contradicted with Abinet could be due to the presence of Phosphorous in Tadesse [16] who stated that there was no its unavailable forms. From this we can conclude significant difference (p> 0.05) on the silt fraction that the establishment of area closure did not between open grazing land and the area bring a significant change on availability of enclosures. Phosphorous. A similar finding (i.e. lower available phosphorous level in closed area than The mean percentage of clay was lower in open in free grazing land) was also reported by Abiy grazing land than the enclosures (Table 1). The Tsetargachew [19] and Abinet [17]. The mean clay content values for the three treatments were values of available potassium values for CGL, 5E statistically significant (P= 0.003). The low and 10E were 0.2, 1.1 and 1.5 (mg/L),

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respectively. The mean values of available the trend Ca2+>Mg2+>Na+ for the three Potassium were significantly different (P<0.0001) treatments. Similar findings were reported by for the three treatments (Table 2). Open grazing other researchers (Abiy Thetargachew [19] and land had lower available Potassium (cmol(+)/Kg Gebremedhin Gebreanenia [21]. soil than the closed area. This is probably due to the selective removal of this vital macro-nutrient 3.2 Some Chemical Properties of Soil from open grazing land by accelerated erosion. Because of its high mobility in the soil, Potassium The mean values of pH stand at 8.9, 8.7 and 9.3 is most susceptible to leaching losses for CGL, 5E and 10E, respectively. The ANOVA [20,17], which might be the reason for the decline revealed that there was significant difference (p= of this vital micronutrient in free grazing land. 0.008) in mean pH values between the soils of Therefore, probably the higher soil leaching rates the Open grazing land and the enclosures at .05 in the grazing land caused lower potassium significant level. This result is contradicted with content. the result got by Abinet Tadesse [17] who described that there was no significant difference Table 2. Primary nutrients in pH between Open grazing land and enclosure. Trt N P K The mean values OM, CEC and EC stands at CGL 0.0±0.0a 3.7±2.2a 0.2±0.1a three treatments were 0.9, 2.3 and 3.0%; 12.8, 5E 0.1±0.0b 3.9±1.6a 1.1±0.2b 18.8 and 21.2 meq/100 g; and 11.7, 11.2 and 10E 0.2±0.0b 6.0±1.0a 1.5±0.0c 11.8(us/cm) respectively. There was higher P <0.0001 0.275 <0.0001 organic matter content in the soils taken from the Note: The units of N, P and K are %, mg/L and cmol enclosures than the open grazing land. One way (+)/Kg soil respectively analysis of variance for organic matter content for the three treatments indicated that there was Table 3. Exchangeable cat ions significant difference (p = 0.000) in mean Organic matter (%) between the three treatments Trt Ca2+ Mg2+ Na+ at 0.05 level (Table 4). CGL 10.4±0.9a 3.2±0.3a 0.8±0.1a 5E 10.8±0.3a 3.8±0.2a 0.82±0.1a The reason for soil organic matter accumulation 10E 10.3±0.6a 3.5±0.4a 0.9±0.1a in the enclosure site could be the higher P 0.683 0.146 0.824 vegetation coverage of enclosure which resulted Note: the units of Ca2+, Mg2+ and Na+ of above is in higher litter input and thus higher accumulation (cmol (+)/Kg soil of organic matter in the soil [22]. The higher clay content of the soil of the enclosures might have Exchangeable cat ions: The mean values of also contributed to higher accumulation of Ca2+, Mg2+ and Na+ for CGL, 5E and 10E stands organic matter in the soils of the enclosures. at 10.4,10.8 and 10.32(cmol(+)Kg-soil);3.2, 3.8 and 3.5(cmol(+)Kg- soil ); and 0.8,0.8 and Soil in the enclosures showed higher in CEC 0.9(cmol(+)Kg- soil ) respectively(Table 3).The than the soil in open grazing land. There was 2+ 2+ + mean values of Ca , Mg and Na for 10E were significant difference (P= 0.002) in mean values higher than that of CGL and 5E.However, there of CEC between the three treatments at 0.05 was insignificant difference (p=0.683, 0.146 and level (Table 4). This could be attributed to the 0.824 respectively) in Ca2+, Mg2+ and Na+ higher soil organic matter and clay percentage of between the three treatments. This suggests that the soil in the enclosure site. Soil CEC is the three treatments did not bring any effect on associated with clay and organic matter colloids, these exchangeable bases. The overall mean and especially organic matter renders soils a exchangeable cat ions (cmol kg-1) of the better CEC [23,24]. Thus, slight difference in Enclosure area and grazing area was followed organic matter can make a big difference in soil

Table 4. Other soil chemical properties

Trt pH OM CEC EC CGL 8.9±0.1a 0.9±0.1a 12.8±2.4a 11.7±0.8a 5E 8.7±0.0a 2.3±0.5b 18.8±0.5b 11.2±0.4a 10E 9.3±0.2b 3.0±0.1b 21.2±1.4b 11.8±2.3a P 0.008 0.000 0.002 0.892 Note: the units of OM, CEC and EC are %, meq/100g and µs/cm respectively

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CEC as observed in this study. Similar findings  The enclosure area should have also clear were reported by other researchers Kibret Mamo and well organized operational manual in [24], Abiy Tsetargachew [19]. They reported order to control successfully, there should higher mean value of CEC in enclosure than free be alternative livestock management grazing lands adjacent to the enclosures. One systems like tethering, instead of letting way analysis of variance for EC for the three livestock to move freely, this will reduce treatments indicated that there was significant overgrazing and increase land productivity difference (p = 0.000) in mean EC (us/cm) in order to increase soil nutrient level in between the three treatments at 0.05 level adjacent grazing lands. (Table 4).  The governmental and non-governmental institutions should create awareness for 4. CONCLUSIONS the community about the importance of enclosure and give full responsibility for The findings in the current study generally show them to develop its sustainable that the management types had a major impact management. on soil properties of rangeland. Some soil quality  For addressing the environmental parameters was observed as a direct effect of problems as well as socio-economic heavy grazing in communal grazing land and this benefits by establishing enclosures, indicates that grazing enclosure results in collaboration among concerned bodies, altering soil physical and chemical properties mainly office of agriculture, local extension which can effect plant growth in the study area. workers, administrative bodies and active The status of the soil in the rangeland is a poor participation of the local people, etc., is both in enclosure and communal grazing area quite indispensable. but in the open-grazed areas was poorer than enclosure due to over grazing pressure while the ETHICAL APPROVAL status of enclosure areas was in better conditions than open grazing area. This was due As per University or academically standard to reduced disturbances. From the result of this written ethical approval has been collected and study, we conclude that enclosures are good preserved by the author(s). options for the rangeland, restoration, rehabilitation, improvement and conservation of ACKNOWLEDGEMENT vegetation and soil in the Shilabo rangeland as a specific and in the Somali Region as general are This study is part of full research about both so important. vegetation and soil under the traditional management practice at the College of dry land 5. RECOMMENDATIONS agriculture Kebridehar University particularly research and technology transfer office. Area enclosure is an advisable and less expensive strategy of soil sustainability and The authors are grateful and express their rehabilitation and it need to be broad practiced sincere gratitude to Kebri dehar University with full involvements of the local community. providing the funds for this research work. The Therefore, consideration ought to be given for authors also extend their special thanks to the expansion of enclosures and considered as Kebridehar TVET College for their assistance, one of the best traditional management practice genuine approach and their kindness in allowing for the protection and restoration against soil us to use the material for soil data sampling. degradation. By the way according to the result of the study, the following suggestions are COMPETING INTERESTS forwarded. Authors have declared that no competing  Open Grazing areas be modified to interests exist. enclosure areas before soil organic and different nutrient contents are depleted REFERENCES more and the administration and conservation exercise carried out in 1. Kassahun A, Snyman HA, Smit GN. enclosure location be bolstered in the Impact of rangeland degradation on future. pastoral production systems, livelihoods

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