Potential Of Agroforestry Research Articles

Agroforestry potential of Ricinodendron heudelotii (Baill.) Pierre ex Pax in Nigeria

With the current geometric increase in Nigerian population and the depleted soil nutrients vis-à-vis decreased agricultural outputs. It becomes pertinent to identify important indigenous multiple agroforestry trees that would be compatible with food crops on the same piece of land for multiple outputs. This study aimed at determining the agroforestry potential of Ricinodendron heudelotii with focus on the ex-situ growth rate of the tree, compatibility with maize as a test crop, coppicing ability and its impact on soil nutrients. The experiment was sited at the Teaching and Research Farm, University of Ibadan, Nigeria, utilizing two alley widths (3 and 6 m) and control (15 × 10 m). Maize plants were intercropped with trees at two different seasons (dry and rain), six months after tree planting, but only the rain season maize survived for further analysis. Data were collected on the height, collar diameter and number of leaves of the trees and maize. Soil analysis was carried out before and after the experiment. The data were subjected to descriptive statistics, ANOVA, t-test, Kruskal Wallis and Mann–Whitney U Test. The results showed that the effect of alley treatment was significant (p < 0.05) on tree and maize growth with the 6 m alley having the highest values. The effect of planting distance was not significant on maize growth. The alley agroforestry practice significantly (p < 0.05) improved the soil properties of the site, especially for pH, available phosphorus, magnesium and natrium. The findings from this study indicated that it is possible to incorporate maize into the alley of Ricinodendron heudelotii for multiple productions.

Carbon Sequestration in Coffee Agroforestry of Barbere District, Bale Zone, Southeastern Ethiopia: Implications for Climate Change Mitigation

Climate change has become one of the most challenges facing the global community today. Human activities, particularly the burning of fossil fuels and deforestation, have increased the level of greenhouse gases, major contributors to global warming in the atmosphere. In spite of this hard fact; there was a growing need to develop strategies that will reduce current levels of greenhouse gases in the atmosphere. One such mechanism is the sequestration of carbon by the agroforestry system. The objective of this study was to determine the above and below ground carbon sequestration potential of coffee agroforestry and indicating their contributions to climate change mitigation. The coffee agroforestry of the study area was divided into three-shade types: monoculture shade cover, intermediate shade covers and densely shaded grown comprises a total area of 261ha, of which 16 samples from the three-shade categories were chosen using lottery method. A total of 48 quadrant plots were laid to sample the coffee agroforestry system. Plot of size 400 m2 was used to measure the shade trees and coffee shrubs. Shade trees with >2.5 cm diameter at breast height were recorded, Coffee shrubs were measured in each 20m X 20m quadrant plot with stem diameter at 15 cm from the ground. Regression equations for estimation of AGB and BGB were established. Results indicate the coffee agroforestry production system that stores the most amount of carbon per hectare in its AGC and BGC was densely Shade (65.69+ 6.27Mg C ha-1), employing a variety of shade-tree species in three distinct layers. Conversely, the shaded monoculture with low structural complexity in its shade layer stores the least carbon (28.85+ 3.93 Mg C ha-1). The carbon-stock of the intermediate shade cover examined falls within this range. The study shows that the coffee agroforestry of Barbere district in southeastern Ethiopia plays a great role in the mitigation of climate change phenomenon by its good potential of carbon sequestration. This study recommends that the shade layer in coffee agroforestry be made denser for increased carbon storage and maintenance of biodiversity. Key Terms: - Agroforestry, Biomass, Barbere, Carbon stock, Mitigation DOI: 10.7176/CER/11-9-01 Publication date:October 31st 2019

Carbon Sequestration in Coffee Agroforestry of Barbere District, Bale Zone, Southeastern Ethiopia: Implications for Climate Change Mitigation

Climate change has become one of the most challenges facing the global community today. Human activities, particularly the burning of fossil fuels and deforestation, have increased the level of greenhouse gases, major contributors to global warming in the atmosphere. In spite of this hard fact; there was a growing need to develop strategies that will reduce current levels of greenhouse gases in the atmosphere. One such mechanism is the sequestration of carbon by the agroforestry system. The objective of this study was to determine the above and below ground carbon sequestration potential of coffee agroforestry and indicating their contributions to climate change mitigation. The coffee agroforestry of the study area was divided into three-shade types: monoculture shade cover, intermediate shade covers and densely shaded grown comprises a total area of 261ha, of which 16 samples from the three-shade categories were chosen using lottery method. A total of 48 quadrant plots were laid to sample the coffee agroforestry system. Plot of size 400 m2 was used to measure the shade trees and coffee shrubs. Shade trees with >2.5 cm diameter at breast height were recorded, Coffee shrubs were measured in each 20m X 20m quadrant plot with stem diameter at 15 cm from the ground. Regression equations for estimation of AGB and BGB were established. Results indicate the coffee agroforestry production system that stores the most amount of carbon per hectare in its AGC and BGC was densely Shade (65.69+ 6.27Mg C ha-1), employing a variety of shade-tree species in three distinct layers. Conversely, the shaded monoculture with low structural complexity in its shade layer stores the least carbon (28.85+ 3.93 Mg C ha-1). The carbon-stock of the intermediate shade cover examined falls within this range. The study shows that the coffee agroforestry of Barbere district in southeastern Ethiopia plays a great role in the mitigation of climate change phenomenon by its good potential of carbon sequestration. This study recommends that the shade layer in coffee agroforestry be made denser for increased carbon storage and maintenance of biodiversity. Key Terms: - Agroforestry, Biomass, Barbere, Carbon stock, Mitigation DOI: 10.7176/CER/11-9-01 Publication date:October 31st 2019

Potential of Agroforestry for Climate Change Mitigation through Carbon Sequestration: Review Paper

Climate change is widely accepted that human activities are now increasingly influencing changes in global climate. Carbon emission is higher from deforestation and forest degradation. However, this can be managed through the sustainable management of land and forest. Thus, the purpose of this review paper is to present the compiled studies which have been done on the potential of agroforestry in climate change mitigation through carbon sequestration. The enhancement of forest C stocks through agroforestry can be considered as one of the main options for reducing greenhouse gases in the atmosphere Agroforestry is a unique extensive action involving the integration of woody plants with crop and livestock components. Therefore, in the recent decades, the role of agroforestry in climate change mitigation received strong attention. Thus, the greatest role of agroforestry in relation to climate change is in mitigating the emissions of CO2 by sequestering carbon from the atmosphere. Because the adoption of agroforestry practice has greater potential to increase C sequestration of predominantly agriculture dominated landscapes than the monocrop agriculture.

Evaluation of Agroforestry Carbon Storage Status and Potential in Irrigated Plains of Pakistan

The Kyoto Protocol includes agroforestry practices as a suggested approach for mitigating global atmospheric CO2. Agroforestry systems are a desirable option for mitigating atmospheric CO2, as they provide numerous secondary benefits, including food, fodder, fuel, increased farm income, biodiversity maintenance, and soil conservation. This research was planned to assess the current carbon storage status and future potential of agroforestry systems in Pakistan through a nondestructive approach (allometric equations) in 14 subdivisions (tehsils) of three selected districts located in the irrigated plains of Punjab, Pakistan. A total of 1750 plots of 0.405 ha each were selected in a randomized, unbiased sampling to estimate the total number of trees, tree species diversity, diameters at breast height (DBHs), and tree heights. Soil carbon was also measured at 0–30 cm using the Walkley–Black method in a subset of plots. It was found that the current number of trees in farms in the study area varied from 18 to 51 trees/ha, which can be increased to 42–83 trees/ha if all the farmers plant the maximum permissible number of trees along with their crops. The estimated total tree carbon stock ranged from 0.0003 to 8.79 Mgha−1, with the smallest mean value of 0.39 Mgha−1 for tehsil Faisalabad, and the largest mean value of 1.41 Mgha−1 for tehsil Chiniot. The whole study area had an estimated woody vegetation carbon stock of 950,470 Mg and a soil carbon stock of 22,743,008 Mg. If farmers in the study area all increased tree stocking to their average maximum desired stocking, the total tree carbon stock would more than double to 2,497,261 Mg. These results highlight both the current and potential carbon sequestration potential of agroforestry in Pakistan and can be further used in devising strategies for implementing tree planting programs on agricultural lands and designing future carbon sequestration projects in Pakistan.

Assessing food sustainable intensification potential of agroforestry using a carbon balance method

Abstract: Food security, climate change mitigation, and land use challenges are interlinked and need to be considered simultaneously. One possible solution is sustainable intensification, which is the practice of increasing food production per area of land whilst also reducing the environmental impacts associated with this. Agroforestry has been stated to be a practice that meets this definition. In this study, a new methodology is presented to assess the potential of different management options as sustainable intensification practices. The methodology is based on comparing the carbon emissions associated with the production of food and the carbon sequestered for that same activity for a particular quantity of food produced over a specific area and over a specific time. The resulting indicator, the “carbon balance” is the difference between the greenhouse gasses emitted (considered as negative values) and carbon sequestered (positive values) estimated in Mg CO2eq per Mg of food produced on one hectare of land for one year. The carbon balance quantifies the global warming potential associated with sustainable intensification by integrating a process-based model with life cycle analysis and is able to estimate above- and below-ground biomass and soil carbon content. This methodology is tested in Portugal for wheat production under crop monoculture and agroforestry systems. The results show agroforestry to be a suitable practice for sustainable intensification compared to a crop monoculture as it just slightly decreased wheat yields whilst providing a positive carbon balance from year 50 onwards of approximately 1 Mg of CO2eq sequestered per Mg of wheat produced.

Effects of rehabilitation pruning and agroforestry on cacao tree development and yield in an older full-sun plantation

AbstractOveraged full-sun cacao plantations and the need for sustainable production systems call for combining rehabilitation of plantations with the establishment of agroforestry. We tested the effect of drastic rehabilitation pruning of old cacao tree stock and the introduction of both high- and low-diversity agroforestry on survival, growth and yield of T. cacao in a commercial plantation in peninsular Malaysia over a period of 5 years. We further determined the incidence of pests and diseases of cacao pods and assessed the performance of the whole system for smallholder farmers, including yields of by-crops. Rehabilitation pruning negatively affected cacao tree development and short-term yield. No more effects of pruning on cacao yield were observed starting in the third year on in the monoculture and starting in the fourth year on in low-diversity agroforestry. We found similar cacao tree development and yield in the low-diversity agroforestry and a common practice monoculture, suggesting that the implementation of agroforestry is a commercially feasible strategy, due to additional income generated through timber production. Reduced cacao tree development and yield in the high-diversity agroforestry were compensated by additional harvests of cassava and banana compared to monoculture. Incidence of cocoa pod borer (Conopomorpha cramerella) was lower in the agroforestry systems, especially the high-diversity system, while the incidence of black pod disease (Phytophthora spp.) did not differ between agroforestry and monoculture. The findings highlight the potential of agroforestry to reconcile ecologically sustainable land use with natural, cost-effective pest management. While pruning needs to be done with timing and disease pressure in mind to minimize short-term yield losses, this measure proved to be a feasible strategy for establishing agroforestry on extant plantations.

Water use of Coffea arabica in open versus shaded systems under smallholder’s farm conditions in Eastern Uganda

Coffee cultivation is a major source of income in East Africa. Increasing temperatures and water scarcity related to climate change are becoming major challenges for coffee production. Therefore, there is an urgent need for sound scientific understanding of the functioning of current coffee cultivation systems and the potential of agroforestry as an adaptation strategy to climate change. In a smallholder coffee farm on Mt Elgon, Uganda, we assessed the effect of three coffee cultivation systems (i.e., Coffee-Open, Coffee-Banana and Coffee-Cordia) on (i) the coffee cultivation environment (e.g. microclimate and soil moisture), (ii) water consumption of coffee, (iii) water consumption of banana (Musa sp.) and Cordia africana and (iv) water competition or complementary use between coffee and shade tree species. To this end, we monitored sap flux density (Js) (g cm−2 hour-1) of coffee, banana and C. africana from March 2015 to April 2016, using Granier thermal dissipation method, along with microclimate, soil moisture and rainfall. Shaded systems reduced irradiance by 70% in Coffee-Cordia system and 58% in Coffee-Banana system compared to Coffee-Open system. Maximum temperatures and daily temperature amplitude were on average reduced by 4 °C in both shaded systems compared to Coffee-Open system. Soil water content (SWC) in shaded systems was reduced by 59% in Coffee-Cordia and 6% in Coffee-Banana compared to Coffee-Open. Daily water consumption of coffee plants was 1.2 ± 0.64 l d-1 and did not differ between systems. Water use of banana was 3.1 ± 1.8 l d-1 and 42 ± 40 l d-1 by C. africana. Coffee-Banana system had the largest daily transpiration rate, 0.9 ± 0.4 mm d-1 per ground area and 0.6 ± 0.4 mm d-1 per unit leaf area, followed by Coffee-Cordia with 0.37 ± 0.1 mm d-1 (per ground area), 0.36 ± 0.1 mm d-1 (per leaf area) and Coffee-Open 0.24 ± 0.1 mm d-1 (per ground area), 0.27 ± 0.1 mm d-1 (per leaf area). Our results showed that differences in microclimate and SWC between cultivation systems did not influence coffee water use during the monitored year. However, water competition between coffee and shade trees could likely occur in drier years, due to the reduced SWC presently observed in shaded systems. Further research is needed to explore the performance of management practices (mulching, pruning and thinning) in interaction with seasonal weather forecast and appropriate selection of shade species (provision of extra products, reduced water use, fast growth and root zone below 80 cm depth) to match the systems’ water requirements with expected soil water availability.

Total Biomass Carbon Sequestration Ability Under the Changing Climatic Condition by Paulownia tomentosa Steud

The concentration of carbon dioxide (CO2) has risen continuously in atmosphere due to human induced activities, and has been considered the predominant cause of global climate change. Paulowina tomentosa Steud. (P. tomentosa), a multipurpose tree is popular around global market for its timber and its potential role in CO2 sequestration. In this study, the total biomass carbon of five years old and newly planted P. tomentosa has been estimated. The results indicated that the average total biomass carbon of five years old plant was found to be 4.52±0.53Kg C Year-1 per tree i.e. 9.04±1.06-ton C ha-1 Year-1 (assuming 2000 plants per hector). Likewise, the average total biomass carbon of newly planted P. tomentosa within 4 months was found to be 6.07±0.38 Kg in remote village area in Nepal. The estimated biomass carbon in one year of newly planted plants was found to be 18.21±1.14 Kg Year-1 i.e. 0.36-ton C ha-1 Year-1. These findings reveled that short rotational trees like P. tomentosa can be implemented in agroforestry system to reduce the green house emission in cities and emphasizes the carbon storage potential of agroforestry. In vitro micro propagation technique could be implemented to produce genetically uniform clone of P. tomentosa and can be applied in agroforestry system for the adaptation and to mitigate global climate change.Int. J. Appl. Sci. Biotechnol. Vol 6(3): 220-226

The potential of agroforestry as an adaptation strategy to mitigate the impacts of climate change: A case study of Kiine Community, Kenya

Nyaruai MA, Musingi JK, Wambua BN. 2018. The potential of agroforestry as an adaptation strategy to mitigate the impacts of climate change: A case study of Kiine Community, Kenya. Nusantara Bioscience 10: 170-177. This study has a purpose of evaluating the agroforestry potent as a conformation policy to the effects of climate change in the location of the study. One hundred farmers were used as study sample in collecting data with stratified sampling technique. To achieve data from individual farmers, both arranged and disarranged questionnaires were used. The study utilized questionnaires and observation timetable to collect data from individual farmers associated with the study objectives. The study found out that more preferable practices in agroforestry were planting the trees and shrubs as windbreakers, riparian forest buffers, silvopasture, and boundary planting while the less preferable practices were forest farming, alley cropping, and woodlots. It also found that the coaching to identify both indigenous and exotic agroforestry tree species is needed. In particular, 94% and 90% of the respondents got a feeling that the coaching on agroforestry practices and incorporation of exotic species is needed very much. The reason is that the feeling felt by respondents could give contribution to shortening the prolonged production time of trees on farm. On the contrary, 90% of the respondents are confident that agroforestry can increase catchment yield in rivers and streams, ameliorate the micro-climate, increase wood production as well as increase livestock health and products. The result showed that agroforestry has a direct link in increasing subsistence of people in the study area. Food (fruits), fodder, fuelwood, medicinal substances, gums, tannins, essential oils, fibers and waxes are the examples of agroforestry products sold by the surrounding farmers. The money will be used to provide second-tier facilities such as paying the tuition for their children or even getting healthcare facilities. The result shows that agroforestry is a method in agricultural production which can decrease the effects of human activities and climate change on the local environment. Agroforestry can increase the endurance of agricultural outturn to contemporary climate variance as well as prolonged climate change by means of the utilization of trees for intensification, diversification and supporting of farming systems.

The utility of farmer ranking of tree attributes for selecting companion trees in coffee production systems

There is increasing interest in the potential of agroforestry to improve the productivity and sustainability of coffee production, but designing management options is knowledge intensive. Tree-crop interactions and the biophysical and socio-economic factors influencing farmers’ decision-making about companion trees are complex and context-specific but fine scale data relating to them are rarely available. A novel method was used to analyse trees ranked by farmers for a range of attributes and evaluate the consistency of farmers’ knowledge underpinning decisions about tree management in coffee production systems in Rwanda. Farmers’ knowledge about tree planting was changing, in line with new shade management recommendations being promoted alongside a limited number of tree species, often freely distributed through eco-certification initiatives. Farmers had detailed knowledge about soil and water conservation processes associated with trees, but they traded these off against perceived competition for light, water and nutrients with coffee. The competitiveness of trees with coffee was influenced by combinations of attributes related to: crown architecture, foliage properties and growth patterns; as well as how trees responded to management, and, their utility. Farmers consistently ranked 20 tree species for 12 attributes (five related to ecology, four to management and three to utility). Given the paucity of data on tree attributes for many species, systematically acquired and consistent local knowledge complements global scientific information and can be useful in bridging knowledge gaps relating to the integration of tree diversity in coffee production systems, which is an increasingly important strategy for smallholder farmers adapting to climate change.

Yield, soil health and moisture status in bael (Aegle marmelos)-based hortipasture system in semi-arid ecosystem of India

A study was conducted from 2008–2009 to 2012–2013 to evaluate the performance of bael-based hortipasture (agroforestry) system under different soil moisture conservation practices in rainfed condition for optimization of system productivity and improvement in soil health. Two cultivars of bael, NB-9 and CISH B-2 were transplanted under square system of planting with 6 × 6 m spacing. The understorey of each plot was intercropped with perennial pastures (grass + range legume) viz; Cenchrus ciliaris + Stylosanthes seabrana to utilize interspaces available between rows. Tree growth, forage yield (green & dry), physico-chemical quality of bael fruit, nutrient buildup and moisture content were found to be better in different moisture conservation treatments over control (without treatment). During the fifth year, tree height (NB-9) ranges from 3.11 to 3.31 m and 2.99 to 3.42 m (CISH B-2) under different treatments. Collar diameter varied from 6.91 to 7.86 cm and 6.81 to 7.56 cm in NB-9 and CISH B-2, respectively. Tree canopy (EW) varied from 1.94 to 2.49 m and 1.68 to 2.17 m and canopy spread (NS) ranges from 1.84 to 2.21 m and 1.85 to 2.28 m in cultivars NB-9 and CISH B-2, respectively. Green and dry forage yield was found to be maximum in staggered trenches (17.88 t/ha and 5.78 tDM/ha). Fruit yield in NB-9 varied from 1.14 to 2.41 t/ha and cultivar CISH B-2 gave 1.74 t/ha fruit yield in staggered trench and 1.11 t/ha in control. Increased Nitrogen, Phosphorus and Potash buildup in soil of experimental site ranged from 3.84 to 15.16%, 7.05 to 21.1% and 4.73 to 15.53%, respectively. Moisture content in staggered trench was 37.08% (at 15 cm depth) and 33.51% (at 30 cm depth) higher than control. Overall productivity of fruit and pasture increased with application of in situ moisture conservation treatments in bael-based hortipasture system. Results revealed that bael-based hortipasture system is a potential agroforestry model for degraded land.

Long term impacts of crop cultivation and tree shading on Piliostigma thonningii (Schumach) Milne-Redhead population, growth and biomass production after charcoal production in central Zambia

Charcoal production in Sub-Saharan Africa is often perceived to have serious ecological and environmental effects even although it does not necessarily result in forest conversion to other land uses. Forest recovery through natural or assisted regeneration is particularly appealing for managing tropical dry forests following degradation by charcoal production because of the coppicing ability of the majority of tree species. However, the impacts of crop cultivation and tree enrichment planting on the regeneration of indigenous trees following charcoal production have rarely been investigated. The present study was conducted on adjacent cultivated and control subplots for over 20 years after charcoal production at a site in central Zambia, southern Africa, to assess the effects of short term crop cultivation, tree enrichment planting and tree shading on Piliostigma thonningii, a potential agroforestry species in sub-Saharan Africa. Seedling emergence, sapling survival and annual tree growth were monitored from 2000 to 2017 and aboveground wood biomass estimated using an allometric equation developed from trees cut at the site and the surrounding area. Seedling emergence from untreated seeds occurred over a 6-year period and tree shading significantly reduced seedling germination and survival. Saplings grew very slowly and none transitioned into a tree after 12 years of observations. Although crop cultivation had no significant effect on the population dynamics of P. thonningii, it reduced tree growth rates, biomass production and peak biomass accumulation. Peak aboveground wood biomass on post-cultivation blocks of 13.7 t ha−1 represented only 61% of the 22.5 t ha−1 on control blocks. Some of the major challenges in cultivating P. thonningii as an agroforestry species are seed dormancy and slow sapling growth and these need to be resolved if the species is to be widely cultivated.

Agroforestry Potential for Increasing Forest and Tree Cover in Himachal Pradesh - An Analysis

Forests and trees are essential for the welfare of people and play significant role in sustainable development. Extent of forest resources is one of the criteria for monitoring the progress towards sustainable forest management. The total forest and tree cover of Himachal Pradesh is 15,453 km² which is 27.76 percent of the state’s geographical area. As per National Forest Policy 1988, the aim should be to maintain two-third of the geographical area of the state under vegetal cover in the hills and in mountainous regions; but there is very little scope for realizing the envisaged target in near future in the state. There is no enough culturable land in the state, as large area of the state is covered under alpine pastures, barren and unculturable wastelands and snow bound areas where trees do not grow. Agriculture in the state is mainly subsistence, and hence there is not much scope of expanding agroforestry in these marginal lands. Therefore, it is prudent to focus more on protecting the existing unspoiled forests, eco-restoration and qualitative improvement of the degraded forests. Positive environment towards agroforestry plantation in the state will motivate the farmers to reap the incentives under Sub-Mission on Agroforestry which will not only fulfill the multiplicity of local requirements but also reduce the pressure on existing forests.

Mitigating climate vagaries through adoption of agroforestry land use in Maharashtra, India

Climate change is the leading ecologic, economic and geopolitical issue of the 21st century and has even the potential to rewrite the global equation for prosperity, development and peace. Adoption of agroforestry land use offers viable option for reducing some of the vagaries arising due to climate change especially the elevated level of CO2 and global warming. The realistic estimates of area and C-sequestration potential of agroforestry are essential for assessing its contribution of agroforestry in climate change mitigation. This has more relevance in current scenario when Maharashtra is facing drought condition especially in Marathawada region. The modern technologies like satellite remote sensing can provide spatially explicit information on land covers and natural resources like water. In the present study, estimation of area under tree cover and agroforestry has been done in Latur, Wardha, Nashik, and Thane districts of Maharashtra. The combination of remote sensing technique and CO2FIX model were applied to estimate agroforestry area and carbon sequestration in selected districts. Dynamic CO2FIX model v3.1 was used to assess the baseline carbon, i.e. year of survey (2013) and to estimate the carbon sequestration potential(CSP) of agroforestry systems for a simulation period of 30 years. Estimated area under agroforestry was in the range of 2.84% in Thane to 5.17% in Latur district and C-sequestration potential ranged from 0.06 to 0.41 Mg C/ha/yr. Study concluded that agroforestry has potential for carbon sequestration vis-Ã -vis climate change mitigation and a viable solution for coping the climate vagaries like drought.

Policies for a Sustainable Biomass Energy Sector in Malawi: Enhancing Energy and Food Security Simultaneously

Summary Biomass energy still dominates the energy sector in Sub-Saharan Africa, in particular as the main cooking energy source in rural and urban areas. The strong linkages to food security and the environment place biomass energy at the heart of sustainable development, a fact that is largely ignored by policy makers in favor of modern energy. At the same time, population and GDP growth are exacerbating already existing supply–demand imbalances in highly populated countries such as Malawi. These trends make it imperative to identify policy interventions that promote sustainable biomass energy while simultaneously considering linkages with other sectors. We use new data on demand and supply for biomass energy in Malawi and develop a model that estimates fuelwood demand based on actual diets and project demand in future years. We simulate how demand side interventions in the form of improved cookstoves affect biomass demand and built a behavioral model to analyze the potential of agroforestry for promoting a sustainable biomass energy sector in Malawi. Our findings show that policy measures aimed at increasing cooking efficiency are not enough to decrease demand for cooking energy due to high population growth. Supply side interventions like agroforestry on the other hand will not only increase sustainable supply, but can also enhance food security and protect the environment. We find that biomass energy can be inherently sustainable and should be an integral part of every energy sector strategy in developing countries as well as of the Sustainable Development Goals.

Drivers of farmers’ decisions to adopt agroforestry: Evidence from the Sudanian savanna zone, Burkina Faso

AbstractIn most developing countries, there has been a long-standing conflict of interest between using land for agriculture and the conservation of biodiversity. This paper reports on a study of factors influencing farmers’ decisions to integrate trees into their agricultural practice. We also discuss the possibility of protecting and managing planted and naturally regenerating trees on farmland in order to restore degraded land and improve biodiversity. Data were collected from interviews with farmers in the Center-West region of Burkina Faso and analyzed using Principal Component Analysis, multiple linear regression and binary logistic regression. The results show that farmers’ decisions to incorporate trees into their farmland were mainly influenced by silvicultural knowledge and skills, participation in farmers’ groups or other social organizations with an interest in tree conservation, the social value of biodiversity in the rural landscape, and the perceived economic benefits of trees on farmland. The most important factors associated with variation in levels of motivation to conserve trees on farms included household wealth, gender, age, education level, marital status, residence status, farmland size, household size and technical support. We conclude that an agroforestry project will be more successful if the local biophysical conditions and diversity of smallholder socio-economic characteristics and their perceptions, needs and preferences are considered in its design. There is also an immediate need for coordinated development of information and training to raise local community awareness of the potential of agroforestry as well as to disseminate information about adding value to tree products in order to encourage farmers to protect on-farm trees.

The potential of agroforestry to reduce atmospheric greenhouse gases in Canada: Insight from pairwise comparisons with traditional agriculture, data gaps and future research

Canadian agriculture is a source of greenhouse gases (GHG) and agroforestry has the potential to sequester carbon (C), and mitigate agricultural GHG emissions. Agroforestry systems are common features in Canada’s agricultural landscape; however, there are limited empirical data to support implementation of agroforestry practices for GHG mitigation. This shortfall of data may be a contributing factor to the lack of policy that supports the use of agroforestry for GHG mitigation in the Canadian agricultural landscape. We reviewed published studies that compared C stocks in vegetation and soils, and/or GHG emissions in agroforestry systems to traditional agriculture across Canada, with the aims of assessing the benefit of adopting agroforestry for GHG reduction. We then identified data gaps and obstacles that could direct future research. We found that most studies reported increases in vegetation and soil organic C storage in areas with woody species compared to herbaceous crops. Agroforestry systems also reduced the emission of CH4and N2O, and increased CO2respiration from soil, but few studies have examined these gases. The small set of studies we reviewed demonstrated the potential of agroforestry to store terrestrial C and mitigate GHG emissions. However, additional research is required to verify this pattern across geographic regions, determine the regional potential for development of agroforestry systems, and assess the potential atmospheric GHG reduction at regional and national scales.

Accurate crop yield predictions from modelling tree-crop interactions in gliricidia-maize agroforestry

Agroforestry systems, containing mixtures of trees and crops, are often promoted because the net effect of interactions between woody and herbaceous components is thought to be positive if evaluated over the long term. From a modelling perspective, agroforestry has received much less attention than monocultures. However, for the potential of agroforestry to impact food security in Africa to be fully evaluated, models are required that accurately predict crop yields in the presence of trees. The positive effects of the fertiliser tree gliricidia (Gliricidia sepium) on maize (Zea mays) are well documented and use of this tree-crop combination to increase crop production is expanding in several African countries. Simulation of gliricidia-maize interactions can complement field trials by predicting crop response across a broader range of contexts than can be achieved by experimentation alone. We tested a model developed within the APSIM framework. APSIM models are widely used for one dimensional (1D), process-based simulation of crops such as maize and wheat in monoculture. The Next Generation version of APSIM was used here to test a 2D agroforestry model where maize growth and yield varied spatially in response to interactions with gliricidia. The simulations were done using data for gliricidia-maize interactions over two years (short-term) in Kenya and 11years (long-term) in Malawi, with differing proportions of trees and crops and contrasting management. Predictions were compared with observations for maize grain yield, and soil water content. Simulations in Kenya were in agreement with observed yields reflecting lower observed maize germination in rows close to gliricidia. Soil water content was also adequately simulated, except for a tendency for slower simulated drying of the soil profile each season. Simulated maize yields in Malawi were also in agreement with observations. Trends in soil carbon over a decade were similar to those measured, but could not be statistically evaluated. These results show that the agroforestry model in APSIM Next Generation adequately represented tree-crop interactions in these two contrasting agro-ecological conditions and agroforestry practices. Further testing of the model is warranted to explore tree-crop interactions under a wider range of environmental conditions.

Shade trees have limited benefits for soil fertility in cocoa agroforests

Agroforestry is often promoted as a sustainable agricultural practice that can ameliorate causes of declining yields, such as soil degradation. However, despite the often-stated potential of agroforestry, quantitative data on the benefits of shade trees are limited to relatively few cropping systems, particularly maize and coffee. Furthermore, agroforests are not cost-free and the benefits of agroforests might not be sufficient to outweigh these costs in all cropping systems or environments. Here we quantify costs and benefits of agroforests for cocoa production in Ghana, West Africa. Specifically, we quantified the ability of shade trees to increase soil carbon stocks and soil fertility (i.e. total soil carbon, nitrogen and phosphorus, available phosphorus and potassium, cation exchange capacity, soil aggregation, pH, and foliar nitrogen and phosphorus concentrations), and investigate if these benefits are sufficient to outweigh the negative effects of shade trees on cocoa growth and yields. We measured cocoa yields, soil fertility and carbon-sequestration under individual shade trees, and in 30 × 30 m plots that were distributed along a gradient of shade-tree cover (plot-scale). We found localized positive effects of individual shade trees on soil carbon and nitrogen content, as well as soil aggregation. However, we found no evidence for positive effects of agroforests via improved soil fertility or carbon-sequestration with increasing shade-tree cover at the plot scale, a scale that more closely matches the scale at which agroforests are managed. Cocoa growth was lower under individual shade trees and decreased with increasing shade-tree cover in plots, and cocoa yields also decreased with increasing shade-tree cover. Our results indicate that the benefits of agroforestry for soil fertility and carbon sequestration in cocoa cultivation systems might not be as extensive as believed, and may not be sufficient to compensate for short-term costs to production.