XIV WORLD CONGRESS, Durban, South Africa, 7-11 September 2015

Bamboo as a land use option for household energy needs and food security in Ghana Samuel T. Partey1, Oliver B. Frith, Michael Y. Kwaku and Daniel A. Sarfo

International Network for and Rattan (INBAR), International Forestry Research Center, Fumesua-Kumasi, Ashanti-Region, Ghana

1Corresponding author. Email: [email protected], Tel: +233 (0) 240 843 963

Abstract Available literature indicates that fuelwood consumption is a major cause of in Ghana. Similar to many parts of Africa, fuels currently provide 71% of Ghana’s total annual energy demand; hence with rising household energy demands, the rates of deforestation and the concomitant negative effects on beneficial ecosystem services are set to increase unless new systems of integrated land uses are developed. In Ghana, sustainable management has been made a priority, and government and scientists are now advocating the use of bamboo agroforestry to reduce pressure on major commercial timber species sometimes sourced for household energy needs. Although Ghana has more than 300,000 hectares of bamboo, it is currently underutilized. Bamboo’s characteristics of fast growth and high renewability make it an efficient and renewable substitute resource for and production. In Asia, bamboo-based intercropping systems are confirmed as suitable land use approaches for increased productivity of food crops and non-food . However, there is limited available data to verify the suitability of the technology in Africa and elucidate the ecological principles by which the system works. Therefore, we are currently conducting a 4-year pilot study in Ghana to: (1) assess local knowledge, governance and economics of bamboo agroforestry; (2) evaluate the ecological interactions within bamboo-based intercropping systems and accentuate implications on soil and crop productivity; and (3) perform a life-cycle analysis of bamboo charcoal using environmental and social indicators. This paper presents the study design, preliminary results and indicates how the premise of the study fits into Ghana’s Growth and Poverty Reduction Strategy. Further, the paper draws on the study’s potential to influence policy and district level recommendations for household energy needs and food security.

Keywords: bamboo, food security, renewable energy, agroforestry

1. Introduction, scope and main objectives According to a recent survey by FAO and JRC (2012), Africa loses about 1.6 million hectares of forest annually. Whilst this is a major improvement from previous estimates of 3.4 million hectares/year (FAO 2010), the current rate is still alarming considering the huge dependence of about 90% of the African populace on forest resources and non-timber forest products. In Ghana, the annual rate of deforestation is about 65,000 hectares (ITTO 2005), which means the country’s substantial forest cover could completely disappear in 25 years. The forest cover of Ghana that contained over 300 species capable of growing to timber size has reduced from 8.2 million hectares in 1984 to the current cover area of 1.3 million hectares. Most interventions and policies, such as introducing annual allowable cuts of 1 million m3 of round logs and bans on illegal chainsaw operation, have not reduced the pressure on . This is attributed to the fact that some of the poorest, rural people depend on the forest for their livelihoods. Available literature points to the fact that fuelwood consumption is one major cause of deforestation in Ghana. It is estimated

1 that 14 million m3 of wood are annually consumed for energy production in Ghana. Similar to many parts of Africa, wood fuels currently provide 71% of the total annual energy demand in Ghana (Energy Commission 2009) and the annual per capita consumption of charcoal for cooking and heating in Ghana is also estimated to be 180 kg (FAO 2001). With rising household energy demands, the rates of deforestation and the concomitant negative effects on beneficial ecosystem services are set to increase unless new systems of integrated land uses are developed.

According to Thevathasan et al. (2011), agroforestry has emerged as one of the most promising approaches to reducing deforestation in the tropics while enhancing rural livelihoods. It is worth mentioning that the use of several woody perennials, such as Senna siamea, Tectona grandis, Leucaena leucocephala, and Acacia spp., has contributed to the development of woodlot agroforestry systems for fuelwood production in Africa. However, the relatively slow growth of these species, their smokiness when burnt, coupled to competing uses and the relative poor quality of the wood for charcoal production, tends to limit their acceptability and adoption potential among many households. In Ghana, sustainable has been made a priority, and government and scientists are now advocating the use of bamboo agroforestry to reduce pressure on major commercial timber species sometimes sourced for household energy needs. Bamboo’s characteristics of fast growth and high renewability make it an efficient and renewable substitute resource for charcoal production. Although bamboo is underutilized for food production systems in Ghana, there are currently more than 300,000 ha of bamboo in Ghana (Obiri and Oteng-Amoako 2007). While experiences from Asia and other countries demonstrate that the integration of bamboo within agricultural systems is a suitable approach for increased productivity of food crops and non-food biomass (Mailly et al. 1997), there is limited available data to verify the suitability of the technology in Africa and elucidate the ecological principles by which the system works. In this pilot study, field trials and socioeconomic studies are currently being carried out to assess the agronomic potential of bamboo agroforestry and its socioeconomic functions in relation to household energy needs and food security. Four thematic areas have been earmarked for the execution of this study:

Theme 1: Ethnobotany and socioeconomic aspects of bamboo agroforestry

Specific objectives: Assess the local knowledge of bamboo; identify challenges/constraints associated with bamboo production; assess the adoption potential of bamboo for arable crop production; and evaluate the economics of bamboo agroforestry

Theme 2: Ecological processes and component interaction within bamboo agroforestry

Specific objectives:Determine the aboveground and belowground biomass and nutrient distribution in a growing bamboo; identify the complementary and competitive zones between bamboo and associated crops; quantify litterfall, decomposition and nutrient release patterns of bamboo fine roots and leaves; evaluate the aboveground carbon-fixing capacity, accumulation and soil organic carbon dynamics in a bamboo-based intercropping system; evaluate crop performance, soil nutrient dynamics and soil moisture conservation in a bamboo-based intercropping system; evaluate shading effect on soil properties and crop performance within a bamboo agroforestry; and evaluate the soil-plant-water interactions in a mixed bamboo-based Agroforestry system.

Theme 3: Life cycle assessment (LCA) of bamboo charcoal

Specific objectives: Characterize the quality of bamboo charcoal and compare likewise with charcoal produced from common biomass sources; compare a range of environmental impacts of producing bamboo charcoal using traditional charcoal production methods. Impacts will be assessed based on the recommendations of the Environmental Protection Agency of Ghana (Greenhouse gas (GHG) emissions,

2 energy consumption, ozone depletion potential, photochemical oxidation, acidification potential, eutrophication potential, and water demand

Theme 4: Suitability of bamboo leaves as fodder for livestock

Specific objectives: Characterize the biochemistry and nutritive value of bamboo leaves; assess the suitability of bamboo leaves as whole feed or feed supplement for livestocks; determine the palatability and digestibility of bamboo leaves; and evaluate growth and development of livestock fed with bamboo leaves either as sole feed or feed supplement

Only preliminary results of Themes 1 and 2 are presented in this paper.

2. Methodology/approach

2.1 Study site The study is being carried out at Jaduako in the Sekyere Central District of Ghana; located within Lat 060551 and 070301N and Long 050001 W (Fig. 1). The District covers a total land area of 1564 km2 and has 150 settlements with 70% being rural. The research area falls within the Dry Semi-Deciduous Forest Zone of Ghana. It is characterized by a bimodal rainfall pattern with an average annual rainfall of 1270 mm. The major rainy season starts in March with a major peak in May. There is a slight dip in July and a peak in August, tapering off in November. December to February is a very long season, which is warm and dusty (the driest period). The area has a mean annual temperature of 27oC, with variations in mean monthly temperature ranging between 22oC and 30oC throughout the year. The soil type of the study site is sandy loam (Ejura – Denteso Association).

Fig. 1: Map of Ghana showing the Sekyere Central District where study is currently being carried out.

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2.2 Field experimentation

2.2.1 Bamboo nursery establishment and transplanting

Two bamboo species were selected for the study: Lowland African Bamboo (Oxytenanthera abyssinica) and Beema bamboo (Bambusa balcooa). B. balcooa was sourced from India in the form of a tissue- cultured propagule, whilst the seeds of O. abyssinica were sourced from Ethiopia. All planting materials were nursed for 5 weeks before field transplant. At the nursery, poultry manure (5 t dry matter ha-1) was applied to the seedlings. During field transplant, O. abyssinica and B. balcooa were allocated to different sites within the same experimental environment. Both bamboo species were planted at an intra-row spacing of 5 m and inter-row spacing of 17 m within 35 x 83 m plots. This was done in four blocks each of size 17 x 35 m. The same design was used for both bamboo species.

2.2.2 Bamboo agroforestry design The bamboo-based intercropping system was designed using a modification of that suggested by Nath et al. (2009). Two separate bamboo-based agroforestry systems were established for both bamboo species with the intercrops receiving either fertilizer application or not. This was done to depict low-input and high-input systems. The alleys of the bamboo were planted with maize (Zea mays), Cassava (Manihot esculenta), Cowpea (Vigna unguiculata) or a Cowpea-Maize rotation system. The selection of the crops was based on the preference of the community where the experiment was sited. Maize (variety- ‘omankwa’-locally bred) was planted at 0.4 x 0.8 m spacing by sowing 4 seeds per hill and to 2 per hill within 2 weeks. Cassava (variety – ‘Ampong’) was planted at a 1 x 1 m spacing using cuttings (of uniform sizes). The cuttings were 40 cm in length. Moreover, cowpea was planted at 0.2 x 0.4 m spacing by sowing 4 seeds per hill and thinning to 2 per hill within 2 weeks. For the cowpea-maize rotation system, cowpea was planted first (beginning from the minor rainy season of 2014). Maize is yet to be planted in the major rainy season trial of 2015. The rotation cycle will be cowpea-maize-cowpea-maize until canopy closure of bamboo. Within the bamboo alleys, zones of potential competition and complementarity were laid out for each intercrop for monitoring purposes.

The experimental design used was a randomized complete block design using the different cropping systems within the bamboo hedgerows as treatments. Controls were included as sole bamboo and maize, cassava and cowpea monoculture systems. As done with the intercropping systems, the monoculture systems were either fertilized or not. Where fertilizer was applied, they were applied at the following -1 -1 -1 -1 recommended rate: maize (90 kg N ha , 60 kg P2O5 ha , 60 kg K2O ha ); cassava (68 kg N ha , 45 kg -1 -1 -1 P2O5 ha , 68 kg K2O ha ) and cowpea (only 60 kg P2O5 ha ).

2.2.3 Soil sampling and analysis The soil conditions at the onset of the experiment were characterized. To do this, soil was collected from 20 locations using a stainless steel auger at within 20cm depth. The soil cores were composited and homogenized by hand mixing before sending out to the laboratory for physicochemical analysis. In the laboratory, soil samples were air-dried till constant weight and passed through a 2 mm sieve and analyzed using five replicates. Soil pH was analyzed using a glass electrode with a soil/water ratio of 1: 2, total N by dry combustion using LECO TruSpecTM CN autoanalyzer (LECO Corporation), organic carbon by the dichromate oxidation method (Motsara and Roy 2008), cation exchange capacity using ammonium acetate extract (Motsara and Roy 2008), available P by the ammonium phosphomolybdate method and soil texture by the hydrometer method (Motsara and Roy 2008). The initial soil characteristics of the study site were: pH (5.8), organic carbon (1.2 g/kg), total N (0.5 g/kg), CEC (4.92 cmol/kg), available P (7.8 mg/kg), available K (82.9 mg/kg), sand (62%), clay (15%) and silt (23%).

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2.2.4 Data collection and analysis Data was collected on bamboo growth characteristics (height and stem diameter), and the shoot and grain yield of maize and cowpea. Cassava is yet to mature for harvesting. The Breast Diameter Height (BHD) of Bamboo culms was measured using an electronic caliper and long field ruler. Data on grain and shoot yield of cowpea and maize were collected per plot within a 4-m2 area. This was done concurrently during harvest. All data recorded were subjected to analysis of variance test at 5% probability level. Where the results were significant, the least significant difference method was used to compare treatment means. All statistical analyses were conducted with Genstat 12 edition.

2.3 Socioeconomic studies on bamboo agroforestry and charcoal governance Two socioeconomic studies are being carried out in this research: one involving farmer-based interviews on the perception of farmers on bamboo agroforestry and the implication of adoption on rural livelihoods and food security; secondary, a study involving expert views on charcoal governance and the potential of bamboo agroforestry as an for meeting household energy needs. The farmer-based interviews are yet to be conducted. Meanwhile, structured questionnaire, and focus group discussions will be used to determine farmers’ knowledge, ecology, usage, and perception on bamboo agroforestry as well as the incentives for the adoption of bamboo-based agroforestry technology in Ghana. Farmers in the study community will be interviewed to ascertain their knowledge base on bamboo cutivation and their readiness to incorporate bamboo cultivation in their farming systems. Social network analysis will be done to establish interactions with farmers- network of information sharing and the line of decision making and choice of farming practices and cropping systems choice and management. Farmer perception will be determined using the Logit or Probit indicator Model. So far, ten expert questionnaire interviews with top officials (up to District Forest Manager positions) of the Forestry Commission of Ghana have been conducted. The officials were purposefully sampled based on their roles in forest governance and production. The results are reported in Section 4.

4. Results and Discussion

4.1 Bamboo growth Analysis of variance test showed significant (p ≤ 0.05) effect of cropping system on the culm diameter and height of both B. balcooa and O. abyssinica (Table 1). Consistently, both bamboo species recorded greater height and stem diameter when planted as monocrops than with the arable crops. The culm diameter of all bamboo species was comparable among the intercropping systems. However, bamboo height was significantly lower when planted with maize and cassava. This observation may be attributed to shading effect by cassava and maize. Considering that the bamboo species would have to adapt to field conditions after transplanting, growth rate was relatively slower than that of the arable crops, which were directly planted at stake. Cassava particularly developed broader and heavy crowns casting partial shade on the bamboo seedlings. Shading is known to impede the growth of plants (Echer et al. 2015) and may account for the greater growth parameters of bamboo recorded on the monocropping field. Meanwhile, among the two bamboo species, B. balcooa seemed better integrated than O. abyssinica per the results obtained so far. As reported in Table 1, growth characteristics of B. balcooa were more than three times greater than O. abyssinica.

4.2 Grain and shoot yield of cowpea So far no significant differences were observed between cowpea planted as a monocrop and intercrop between bamboo rows. This may at this stage demonstrate some degree of compatibility between cowpea and bamboo as there were no clear indications of the components adversely affecting each other. Meanwhile, the application of P fertilizer significantly (p < 0.05) increased the grain and shoot yield of cowpea either as a sole crop or as an intercrop (Table 2). The initial soil test results showed the soil at the project site was relatively low in P, which necessitated the application of triple superphosphate. Generally, the production of cowpea with P fertilizer application is highly recommended (particularly on

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P limiting soils) considering the effect on N fixation and the agronomic performance of cowpea. This result is consistent with previous studies that have found greater yield responses of cowpea to P fertilizer application (Ahamefule et al. 2014; Odundo et al. 2014).

Table 1: Growth characteristics of B. balcooa and O. abyssinica planted as monocrops or integrated with cassava, cowpea and maize over six months under field conditions at Jeduako in the Sekyere Central District of Ashanti, Ghana Bamboo cropping systems B. balcooa O. abyssinica

Culm Height Culm Height diameter (m) diameter (m) (mm) (mm) Bamboo monocropping system 44.08 (0.12) 3.89 (0.05) 10.70 (0.25) 1.86 (0.03) Bamboo + Cassava intercropping 31.80 (0.08) 3.51 (0.04) 4.05 (0.27) 0.87 (0.05) system Bamboo + Cowpea intercropping 33.31 (0.24) 3.73 (0.03) 9.53 (0.21) 1.56 (0.01) system Bamboo + Maize intercropping 33.51 (0.30) 3.59 (0.06) 7.55 (0.28) 1.48 (0.01) system

P value < 0.001 0.001 < 0.001 < 0.001 LSD at 5% 0.683 0.146 0.914 0.10

Values are the means of 4 replicates. Values in parentheses are standard error of means. LSD = Least Significant Difference.

4.3 Grain and shoot yield of maize The results on maize were similar to that of cowpea. Neither the type of cropping system nor its interaction with inorganic fertilizer significantly affected the grain and shoot yield of maize. However, the application of fertilizer significantly (p ≤ 0.05) increased both the shoot and grain yield of maize. Relative to the control, fertilizer application increased shoot and grain yield by about 134% (Table 3). Although inorganic fertilizers are relatively expensive to most resource-poor smallholder farmers in Africa, they continue to be part of farming systems. Increased crop productivity with inorganic fertilizer application is highly reported (Partey and Thevathasan 2013; Zhu et al. 2015) and consistent with the results obtained in our preliminary investigations.

4.4 Charcoal governance and socioeconomic aspects of bamboo agroforestry

The objective of the study was to establish whether charcoal production was formalized in Ghana and determine land tenure issues that could constrain bamboo cultivation in Ghana. Average working experience of the respondents was 23 years. They had at least an undergraduate degree in forestry and had run through the ranks to become either forest district managers or operation directors.

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Table 2 Grain and shoot yield of cowpea as affected by fertilizer application and cropping systems at Jeduako in the Sekyere Central District of Ashanti, Ghana Treatments Grain yield (t ha-1) Shoot yield (t ha-1) Factor A: Cropping System Bamboo + Cowpea intercropping system (BCinter) 1.25 (0.03) 1.87 (0.08) Cowpea monocropping system (Cm) 1.23 (0.04) 1.91 (0.09) P value 0.229ns 0.644ns

Factor B: Fertilizer (TSP) TSP 1.32 (0.01) 2.04 (0.04) No TSP 1.16 (0.02) 1.74 (0.08) P value < 0.001*** 0.004** LSD at 5% 0.035 0.175

Cropping system x Fertilizer interaction BCinter x TSP 1.32 (0.02) 2.02 (0.05) BCinter x No TSP 1.18 (0.02) 1.72 (0.12) Cm x TSP 1.33 (0.001) 2.06 (0.07) Cm x No TSP 1.13 (0.02) 1.75 (0.11) P value 0.085ns 0.894ns Values are the means of 4 replicates. Values in parentheses are standard error of means. TSP = triple -1 superphosphate applied at 60 kg P2O5 ha , LSD = Least Significant Difference. LSD was determined where p ≤ 0.05. ** and *** refer to statistical significance at 1% and 0.1% probability levels respectively, ns = not significant at 5% probability level.

Table 3: Grain and shoot yield of maize as affected by fertilizer application and cropping system at Jeduako in the Sekyere Central District of Ashanti, Ghana Treatments Grain yield (t/ha) Shoot yield (t/ha) Factor A: Cropping System Bamboo + Maize intercropping system (BMinter) 2.02 (0.16) 3.10 (0.19) Maize monocropping system (Mm) 1.88 (0.14) 3.27 (0.19) P value 0.341ns 0.102

Factor B: Fertilizer (F) F 2.24 (0.07) 3.62 (0.11) No F 1.67 (0.15) 2.70 (0.07) P value 0.003** < 0.001 LSD at 5% 0.458 0.241

Cropping system x Fertilizer interaction BMinter x F 2.24 (0.07) 3.51 (0.18) BMinter x No F 1.81 (0.29) 2.64 (0.07) Mm x F 2.24 (0.05) 3.73 (0.13) Mm x No F 1.52 (0.03) 2.81 (0.10) P value 0.336ns 0.837 Values are the means of 4 replicates. Values in parentheses are standard error of means. LSD = Least Significant Difference. LSD was determined where p ≤ 0.05. ** and *** refer to statistical significance at 1% and 0.1% probability levels respectively, ns = not significant at 5% probability -1 -1 -1 level. Fertilizer was applied at 90 kg N ha , 60 kg P2O5 ha , 60 kg K2O ha

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4.4.1 Charcoal governance

Responses from the interviews showed charcoal production is not formalized in Ghana and that formalizing charcoal has not been given any full considerations yet. The following factors were identified as barriers to formalizing charcoal production: land tenure system, lack of policies and permit systems, lack of proper documentation and data on preference for charcoal; and inadequate technical staff strength and logistics for the Forestry Commission (FC). From respondents’ own experience, species used in charcoal production are sourced from either the natural forest, farmland or woodlot . However, the level of dependence on the natural forest was deemed highest, which poses threat to deforestation. From the FC, there is currently no available policy that allows charcoal producers to cut from the forest for charcoal although the latest 2012 Forest Policy talks about the need for regularizing woodfuel harvesting off forest reserve. Further, it was confirmed that species used for charcoal production were enormous and may be determined by the ecological zone. For instance, it was shown that Senna siamea and Neem (Azadirachta indica) were predominantly used in the Coastal Savanna; in the middle belt, Celtis spp., Triplochiton scleroxylon, Pycnanthus angolensis, and Terminalia ivorensis whilst Adansonia digitata, Azadirachta indica, Rosewood (Dalbergia spp.) are predominantly used in the Northern Savannah zone.

Considering the threats charcoal production pose on biodiversity, respondents showed the FC has encouraged private commercial producers, individuals and communities to establish their own forest plantations. Meanwhile, no significant successes have been reported considering individuals and communities are expected to source for seeds, make their own nurseries and transplant unto the field. The FC confirmed that issues of funds unavailability, land tenure, lack of motivation and weak law enforcement that restricts forest encroachment constrain the development.

4.4.2 Bamboo cultivation and land tenure issues According to the FC, bamboo is not deliberately planted in Ghana except where it is used for experimental trials. Meanwhile it was confirmed that the FC is currently promoting the use of bamboo biomass to reduce the pressure on the forest. In addition, the FC has seconded staff to assist Bamboo and Rattan Development Programme (BARADEP). Also, a relatively large number of technical staff have been trained in Bamboo technology in China to help in the promotion of bamboo cultivation and utilization in Ghana. The interview results showed that the forestry sector of Ghana does not have any bamboo plantations yet considering bamboo plantation development is a relatively new concept in Ghana. However, it was confirmed that few trial plots in Subri Forest Reserve (Takoradi), Nkawanda Forest Reserve (Mpraeso) and Brimso Forest Reserve (Cape Coast) are currently being established. The FC was aware quality charcoal could be produced from bamboo. This was known through a pilot project at Daboase in the Western Region, which was jointly executed by the Forestry Research Institute of Ghana (FORIG) BARADEP, and INBAR. While the FC agreed bamboo cultivation for charcoal could ease the pressure on forest resources, it was likely to face land tenure challenges especially outside forest reserves. Bamboo cultivation may also compete with other land use systems. However, it is likely to be less problematic in Forest Reserves, which have been zoned in line with Forest Management presentations.

5. Conclusions/outlook The results of our preliminary studies may not be strong to make solid conclusions at this stage. However, the results give clues to hypothesize in our on-going research that maize and cowpea may have better integration with bamboo than cassava. Cassava may impede the growth of young bamboo seedlings due to shading effects. This provides useful information on managing spacing of cassava within bamboo alleys. In addition, the results provided evidence to believe that beema bamboo may have better integration with the selected crops and be more adaptable to site conditions than abyssinica. From our socioeconomic studies, it was evident that charcoal production is not formalized in Ghana although policies that restrict encroachment of forest reserves for trees are in place. Deliberate planting of bamboo is a new concept in Ghana and its currently being tried in some parts of the country. The Forestry Commission attests that bamboo plantations could minimize deforestation

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and must be promoted. However, bamboo cultivation may face land tenure issues and compete with other land use systems considering the pressure on land resources. Example, an average landholding per family is less than 0.5 ha and so farmers may not be interested in expanding cultivation of bamboo.

Acknowledgements The authors wish to express their appreciation to the entire Biomassweb working groups and partners for their utmost support. The funding support from the German Government (The Federal Ministry of and Research) in the execution of this research is highly appreciated.

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