Cocoa Agroforestry Systems Research Articles

A rapid tree diversity assessment method for cocoa agroforestry systems

Biodiversity is recognized as an essential part of sustainable development efforts, however reducing biodiversity loss is a key global challenge that requires updated data on biodiversity status at different scales. Cocoa agroforests include tree species besides cocoa, a practice beneficial to biodiversity, ecosystem conservation and farming households. We present a stepwise procedure to test and select a method that rapidly assesses biodiversity in cocoa agroforests based primarily on species richness and counts of non-cocoa trees. Three rapid assessment methodologies (RapidBAM) with different sampling procedures were tested in three phases: calibration, testing and evaluation. Results showed the method using the lowest number of sample plots with a minimum area coverage and a consistent sampling time (regardless of farm context) provided the most accurate and straightforward assessment. Farmers accurately reported qualitatively on species, complimenting quantitative data produced by RapidBAM. Collecting biodiversity data with RapidBAM proved valuable to collect data at large-scales and is applicable to different landscapes. Monitoring biodiversity with fewer required resources than conventional methods is a relevant outcome, which can help defining efficient biodiversity-friendly farming practices.

Socio-economic assessment of different cocoa agroforestry systems in the forest-Savannah transition zone in central Côte d’Ivoire

ABSTRACT Cocoa production in Côte d’Ivoire is generally based on “full sun” crops. However, the presence of traditional agroforestry systems based on cocoa (AFSc) has been highlighted in several regions including the Centre and Centre-West. This study aimed to provide information on the financial profitability and the potential economic value of simple, mixed and complex AFSc types identified in central Côte d’Ivoire. A socio-economic survey and direct observations carried out among farmers with these AFSc types, revealed an annual average cocoa production of 207.7 kgha−1 (i.e. US$323.9). This income does not vary significantly from one type to another. Fruit species associated with cocoa trees yield an average of US$32.39 ha-1yr-1. This fruit contribution is more important in simple AFSc than in the two other types. Considering the profitability of cocoa trees and associated species, no system is more profitable than the other. However, the potential economic value of the stored carbon and the other benefits that the complex AFSc type provides to farmers make this type more efficient and sustainable than the two others considering ecosystem services. We therefore recommend that payment for ecosystems services be considered if one would like to promote complex cocoa agroforestry systems in the study areas.

Upper canopy tree crown architecture and its implications for shade in cocoa agroforestry systems in the Western Region of Ghana

Several studies have been conducted on shaded cocoa systems, but few of these have examined species-specific crown architecture of upper canopy trees and its influence on shade provision in cocoa agroforestry systems. In view of the fact that cocoa agroforestry is a recommended practice to drive cocoa production onto a climate-smart pathway, and given the role of upper canopy trees in the moderation of shade and light to the cocoa system, there is the need to understand the dynamics of upper canopy crown as well as dendrometric parameters and how these parameters influence shade provision for the cocoa system. Employing a replicated transect method, quantitative data on upper canopy trees in cocoa agroforestry systems were collected from twelve (12) 1 ha plots established on a 5 km long transect at the Bonsu Nkwanta cocoa growing district in the Western Region of Ghana. Given that there was no existing information on various crown forms of upper canopy trees in cocoa systems in Ghana, the crown forms generated by (Frank, 2010) were adopted for this study. These were “spreading to cylindrical”, “elongate to rounded to oval”, “upswept and vase shaped”, “conical to pyramidal” and “spade shaped” crown forms. One hundred and sixty (160) upper canopy trees comprising of 44 species, which were distributed in 21 families were recorded in the cocoa agroforestry systems surveyed in the study area. Newbouldia laevis was observed to be the most abundant species recorded in the sampled farms. The results showed that crown and dendrometric characteristics of the upper canopy trees did not differ in cocoa agroforestry systems of different ages. Also, the highest values of crown volume, crown area and shade area were recorded by the “spreading to cylindrical” crown forms followed by the “elongate” crown form, respectively. Furthermore, the study showed that crown area, crown volume, crown diameter, tree DBH and crown height were the parameters that strongly affected the ability of a particular crown form of a tree to provide higher shade. Based on the results, we conclude that in selecting upper canopy trees for the provision of shade in cocoa agroforestry systems, trees with “spreading to cylindrical” and “elongate” crown forms are the most suitable crown forms to incorporate in cocoa agroforestry systems. However, these constituted the least crown forms in the cocoa systems studied. The study provides a useful guide to the selection and management of upper canopy tree species for the provision of shade in cocoa agroforestry systems, and holds further applications for the provision of decision support for the promotion of climate – smart cocoa agroforestry in Ghana and the West African cocoa belt.

Carbon and nutrient cycling in tree plantations vs. natural forests: implication for an efficient cocoa agroforestry system in West Africa

Nutrient cycling has been widely studied in tree plantations. However, studies on the observed negative changes relative to natural vegetations and how these could be capitalized toward setting up ecofriendly agroecosystems are rare. This study was conducted in Central-West Cote d’Ivoire to establish the changes in carbon and macronutrient cycling occurring in full-sun cocoa (Theobroma cacao L.) and Teak (Tectona grandis) relative to primary forest and subsequently make cocoa agroforestry-based recommendations. Leaf litterfall and associated carbon and macronutrient inputs, rates of leaf litter decomposition, and macronutrient release were assessed. In addition, soil (0–10 cm depth) chemical and microbial parameters were evaluated. Litterfall yields were 10.6 ± 2.0, 9.3 ± 0.8, and 10.1 ± 0.4 Mg dry mass ha−1 year−1 in forest, cocoa, and teak, respectively. Compared to the forest, the cocoa plantation supplied lower inputs of C (−736 kg ha−1 year−1 or −15.5%) and N (−75 kg ha−1 year−1 or −27%), similar P, but greater K. Similar quantities of C and N were recorded in the teak plantations and the forest. However, the teak plantation supplied lower K but higher P inputs than the forest. Cocoa leaf litters decomposed at the same rate as those of the forest (k = 0.3 month−1) but faster than the teak’s, the initial leaf litter N:P ratio being the most influencing factor. Except for P, the macronutrient release from cocoa and forest litters exhibited similar patterns and rates, which were significantly different from those observed in the teak leaf litter. Soil C mineralization rate and mineral N concentration drastically declined in both tree plantations, the greatest gap occurring in cocoa (Cmin: −40%, mineral N: –54.2%) due to lower litter Ca input and soil acidity. Teak appears to be a good candidate for shade as it may compensate for the deficit in litter C (and N, to a lesser extent) supply exhibited by cocoa relative to the forest. The trends in microbial activity underscore the need to grow cocoa in association with trees that provide quality litter materials, for improved cocoa nutrient availability and faster C storage in soil. In line with this, some suggestions were made and discussed. This study can be used in support of developing an efficient cocoa agroforestry system in West Africa.

Dispersion patterns and monitoring samplings of termite pests in cocoa agroforestry systems of Southern Cameroon

Termites are major emerging pests of cocoa in Africa. However, their dispersion models on cocoa trees as well as their sampling plans remain unclear. Moreover, the effect of shade trees on the severity of termite infestation on cocoa is poorly known. We evaluated the severity of termite infestation on cocoa trees in relation to shade management in five cocoa agroforestry systems in southern Cameroon with shade cover ranging from rustic to full sun. The dispersion models of termites on cocoa were analyzed using Taylor’s power law, Nachman model and Iwao’s method. We then simulated the optimal sampling sizes for pest monitoring based on parameters of the best-fitted dispersion model using Southwood’s and Green’s formulas. Our results suggest that shade trees reduce belowground infestation by termites and encourage aboveground infestation; however, belowground infestation is more severe. Taylor’s power law was the best-fitted model to describe the aggregative dispersion pattern of termites on cocoa trees. The estimated sampling plans suggested that Green’s sampling was more precise for termites sampling, where less trees is required, than Southwood’s sampling. This study is pioneer on dispersion patterns and sampling plans of termites on cocoa and could be used by researchers and farmers for decision making about pesticide application.

Litterfall seasonal dynamics and leaf-litter turnover in cocoa agroforests established on past forest lands or savannah

Nutrient cycling in cocoa agroforestry systems (cAFS) is complex and poorly understood. To better understand the mass flow of carbon and nutrients into the soil sub-system under various contexts we quantified the mass flow of litterfall, its composition and seasonal variations in different agroforestry systems in Bokito (Central Cameroon). We studied litterfall dynamics and in situ leaf-litter cycling of cAFS established on past forest lands (F-cAFS) and savannah (S-cAFS). We also studied the decomposition of cocoa and associated tree leaf-litter in litterbags. Local secondary semi-deciduous forests were included as control. Annual litterfall in full-grown cAFS (> 15 years old) was high (9.4 Mg ha−1 y−1) and represented ca. 67% of litterfall in control forests. In full-grown cAFS, associated tree leaf-litter contributed to litterfall the most and ranged between 60 and 70% of the total amount recorded (6.3 Mg ha−1 y−1). The quantities and dynamics of the litter components monitored were similar in full-grown S- and F-cAFS. The microclimate was best buffered in forests and least buffered in young S-cAFS but could not be linked to leaf-litter decomposition. Forest leaf litterfall was higher and tended to cycle faster than total leaf-litter of cAFS, whose decomposition appeared limited by cocoa leaf-litter quality. Our study underlines (i) the critical contribution of associated trees to the nutrient cycle of agroecosystems established on poor soils and, (ii) the ability of farmers to channel associated tree communities towards similar functioning despite different past land-uses.

Working towards Sustainable Innovation for Green Waste Benefits: The Role of Awareness of Consequences in the Adoption of Shaded Cocoa Agroforestry in Ghana

Drawing on the awareness of consequence literature, this paper unpacks how the awareness of the consequences of full-sun cocoa production can encourage farmers to adopt shaded cocoa agroforestry that preserves the land and favours better cocoa farm waste management. Using Ghana as a case study, the paper provides distinctive insights on how shaded cocoa agroforestry systems provide sustainable yields in the medium- to long-term, relative to unshaded systems. We also find that cocoa farmers’ awareness of consequences about the effects of undertaking unshaded cocoa production could make individual farmers exhibit pro-environmental behaviour, leading to the adoption of cocoa agroforestry systems that help preserve soil fertility and improve waste management. We recommend that the utilization of awareness of consequence protocols, coupled with the efficient diffusion of information on the benefits of agroforestry in terms of waste management and environmental improvements to the cocoa farmers, could increase the adoption of shaded cocoa production regimes in Ghana.

Rehabilitation practices in cocoa agroforestry systems mitigate outbreaks of termites and support cocoa tree development and yield

Most smallholder cocoa farmers in West Africa are not equipped with the necessary tools, techniques, and practices to rejuvenate their aging cocoa farms. Instead, they rather prefer to establish new cocoa farms at the expense of forest remnants. Poor management of their overaged farms has resulted in the emergence and outbreaks of new pest species such as termites feeding on the remaining productive trees and negatively affecting overall yield. We investigated how rehabilitation pruning of cocoa trees influences termite outbreaks and yield in three cocoa agroforestry systems (rustic, intermediate and full sun systems). We monitored cocoa and non-cocoa trees at different development stages after rehabilitation pruning and assessed termite diversity and damage. We demonstrated that farm rehabilitation practices are associated with high beta diversity of shade trees and linked with a high diversity of beneficial termite species. Cocoa trees and farm age were positively correlated with the level of infestation by termite species. We also showed that rehabilitation practices improve cocoa tree vigor and yield in cocoa agroforestry systems with the intermediate systems as the most productive after pruning (167 % of yield increase after pruning). Rehabilitation pruning is a suitable practice to rejuvenate aging trees and increase short-term cocoa yield while mitigating the negative effects of insect pests such as termites. It could be recommended as an effective measure for sustainable cocoa production, thereby enhancing ecosystem services provided by local biodiversity and avoiding forest clearance.

Estructura y carbono específico en una cronosecuencia de sistemas agroforestales de Teobroma cacao L. en Tabasco, México

Ante el impacto que representa el cambio de uso de suelo en la pérdida de biodiversidad y deterioro del medio ambiente, los sistemas agroforestales de cacao de sombra son una alternativa para la conservación de biodiversidad y almacén de carbono. El objetivo de este trabajo fue conocer el efecto de la edad de los sistemas agroforestales de cacao en la diversidad arbórea y almacenes de carbono de su vegetación de sombra. Se compararon 258 parcelas distribuidas en once sistemas agroforestales entre 10 años y 70 años, totalizando 7.87 ha. Dentro de cada parcela se midió el diámetro normal (DN) y altura total de todos los árboles >5 cm (DN) para estimar su biomasa aérea con una ecuación general y otra específica, y conocer la discrepancia de ambos métodos. Los sistemas agroforestales de 70 años presentaron en promedio más especies arbóreas por hectárea (23), índice de diversidad Shannon (2.0) y almacén de carbono (75 Mg ha-1) que los de 10 años (p < 0.01; 10 Mg ha-1, 1.1 Mg ha-1 y 36 Mg ha-1; respectivamente). La ecuación alométrica específica estimó 27.7% (p = 0.05) más biomasa aérea que la ecuación general, por lo que se considera de mayor precisión para estos sistemas agroforestales en particular, y se recomienda su uso para estos tipos de vegetación. Se concluye que, particularmente para México, conservar sistemas agroforestales de cacao de edad madura contribuye a la conservación de la biodiversidad arbórea y almacenes de carbono de la vegetación tropical, asemejando relictos de la vegetación original.

Decomposition and nutrient mineralisation of leaf litter in smallholder cocoa agroforests: a comparison of organic and conventional farms in Ghana

PurposeAlthough litter decomposition and nutrient release patterns have been studied in cocoa agroforestry systems in general, studies focusing on organic and conventional cocoa systems are lacking which is critical as organic farms are particularly dependent on nutrient returns from decomposing litter.Materials and methodsDynamics in leaf litter decomposition and the mineralisation of macro- and micro-nutrients in organic and conventional cocoa agroforestry systems were studied using the litterbag technique for 12 months.ResultsThe average monthly mass loss was more than two times higher on organic farms (9.2–14.4 g month−1) compared to conventional farms (4.2–7.3 g month−1) in the first five months. The annual rate of decomposition (k) was higher on organic farms (1.9) compared to conventional systems (1.4). The time required for 50% (t50) and 99% (t99) decomposition of leaf litter was both lower on organic farms (t50 = 0.4 years, t99 = 2.6 years) than conventional farms (t50 = 0.5 years, t99 = 3.5 years). The estimated k values for macro- and micro-nutrients on organic cocoa systems ranged from 2.3 for calcium to 4.5 for potassium compared to 1.6 (Ca) to 2.8 (K) on conventional farms. The k values of all nutrients (except nitrogen and phosphorus) were significantly greater on organic farms than conventional systems. The estimated k values for both litter decomposition and nutrient mineralisation correlated with soil pH and moisture content, but not initial litter chemistry.ConclusionsOrganic management of smallholder cocoa agroforestry systems enhanced leaf litter decomposition and nutrient mineralisation through improved soil conditions. Thus, organic management of cocoa agroforestry systems may contribute to sustainable cocoa production in smallholder systems through enhanced nutrient return from litter decomposition.

Simplification of the structure and diversity of cocoa agroforests does not increase yield nor influence frosty pod rot in El Soconusco, Chiapas, Mexico

Cocoa is traditionally grown in agroforestry systems (AFS). It is essential to the household and regional economy and plays an important role in natural resource and environmental services conservation. In recent years, the vegetation structure and diversity of cocoa AFS throughout the world are being simplified as farmers consider that the removal of trees helps to increase yields and reduce disease incidence. However, debate exists on the relationship between tree shade and diversity and cocoa yields and the incidence of disease such as frosty pod rot, one of the most important fungal infections in cocoa cultivation. The objective of this study was to analyze changes in agroforestry structure, plant species diversity, uses, yields, the incidence of frosty pod rot disease in cocoa agroforestry systems, and discuss the consequences of the simplification of this particular AFS in the municipality of Acacoyagua, Chiapas, Mexico. Inventories were carried out in 27 plots. Interviews were applied to families to assess ecological, technical, and productive variables. Incidence of frosty pod rot disease and yields were estimated on-farm and through interviews over a period of 3 years. Multivariate cluster analysis, Pearson correlation analysis, the Levene test for equality of variances and a non-parametric U Mann–Whitney test were carried out. Three types of cocoa agroforests were identified as a result of a structure simplification: (1) traditional cocoa polyculture; (2) cocoa with Legumes Inga spp and Lonchocarpus spp.; and (3) cocoa with diverse, scattered, predominantly wild trees. Fifty species were recorded in shade vegetation, with a diversity index of 3.15. Simplification in tree structure did not have a significant effect on cocoa yield nor on the incidence of frosty pod rot disease. On the contrary, it resulted in a decrease in plant diversity and provisioning of food and other products. Farmers undertake few agricultural practices; some practices are eventually carried out, such as the pruning of cocoa trees and shade-trees, removal, and burial of diseased fruits, and weeding. Seven out of 27 plots sampled yielded more than 300 kg ha−1, and one plot attained a yield of 437.5 kg ha−1; however, yields averaged 155.8 kg ha−1 and incidence of frosty pot rot averaged 9.6%, regardless of AFS type. These results highlight the importance of improving AFS management which in this case appears to be the most critical factor for attaining an increase in yields. Low levels of production and the incidence of frosty pod rot subsequently reduces farmers’ motivation to continue cultivating cocoa, placing the crop at risk and increasing the possibility of a change in the land-use.

The morphological and molecular characterization of Trichoderma spp. in cocoa agroforestry systems

Species of the genus Trichoderma have been used as growth inhibitors and regulators of phytopathogens. The aim of this work was to study and molecularly characterize the species of the genus Trichoderma that can be found in the rhizosphere of cocoa agroforestry systems in the state of Tabasco, Mexico. Four composite samples were taken from each of three municipalities (Cardenas, Comacalco and Cunduacan). Thirty homogeneous sub-samples were taken (0-30 cm of depth) from each site (plantation) in a random zig-zag pattern across the middle part of the plantations, avoiding the edges. Thirteen strains of the Trichoderma genus were isolated and morphologically identified, while two species, T. harzianum and T. koningiopsi, were molecularly identified. Of the 13 strains, only five were amplified, and of these five, four corresponded to T. harzianum and one to T. koningiopsi.

Farmers\u2019 Perceptions as a Driver of Agricultural Practices: Understanding Soil Fertility Management Practices in Cocoa Agroforestry Systems in Cameroon

In Africa, cocoa yields are low, partly due to soil fertility constraints and poor management. While peoples’ knowledge, aspirations, and abilities are key factors explaining their behaviour, little is known about the rationales that underpin soil fertility management practices (SFMPs) of cocoa farmers. To address this gap, we conducted an exploratory survey in two contrasting regions in Cameroon where cocoa is an important crop: the humid forest and the forest-savannah transition zone. Some 30% of farmers in the transition zone as opposed to 13% in the humid forest expressed concerns about soil fertility. The most relevant soil fertility indicators for farmers were high cocoa yield, dark soil colour, ease of tillage, and floral composition. To enhance and maintain soil fertility, farmers used residues from weeding (100%), planting of trees (42%), mineral fertilisers (33%), compost (16%), and manure (13%). More farmers in the transition zone than the humid forest implemented SFMPs. Our findings suggest that soil fertility perceptions, access to inputs, local practices, and experience influence farmers’ use of SFMPs. The limited use of mineral fertilisers was explained by poor access whereas the use of organic fertilisers and tree planting were mostly constrained by lack of labour and knowledge. Farmers prioritised practices to increase yield and viewed SFMPs to be the least important management practices, although they believe high cocoa yield is an important indicator of soil fertility. To foster sustainable cocoa intensification, it is necessary to enhance farmers’ knowledge on SFMPs, increase access to inputs, and ensure returns on investment while considering farmers’ priorities and practices.

Influence of organic cocoa agroforestry on soil physico-chemical properties and crop yields of smallholders’ cocoa farms, Ghana

AbstractThe success of sustainable Theobroma cacao (cocoa) production depends on the physical and chemical properties of the soils on which they are established but these are possibly moderated by the management approach that farmers adopt. We assessed and compared soil physico-chemical properties of young, mature and old organic and conventional cocoa agroforestry systems at two depths (0–15 and 15–30 cm) and evaluated the production of cocoa pods, banana and plantain in the two farm types. Cocoa farms under organic management had 20, 81, 88 and 323% higher stocks of soil organic carbon, P, Mn and Cu, respectively, compared to those under conventional management. Higher soil moisture content, electrical conductivity and pH were found on organic systems than the conventional farms. Annual cocoa pod production per tree was similar in both cocoa systems (Org. 10.1 ± 1.1 vs Con. 10.1 ± 0.6 pods per tree). The annual production of banana and plantain was higher on organic farms (186.3 ± 34.70 kg ha−1 yr−1) than conventional systems (31.6 ± 9.58 kg ha−1 yr−1). We concluded that organic management of cocoa agroforestry systems result in soils with the greater overall quality for cocoa production than conventional management and it increases the yield of co-products. Studies focusing on the impact of organic management on cocoa agroforestry systems at the landscape and regional scales are urgently needed to further deepen our understanding and support policy.

Landscape composition is more important than local vegetation structure for understory birds in cocoa agroforestry systems

Biodiversity-friendly agricultural systems allow the maintenance of native species even in highly fragmented landscapes by providing corridors to species dispersion and offering supplementary resources for animal populations. In the tropical region, cocoa agroforestry systems are of great importance for biodiversity conservation as they maintain part of the native vegetation, and therefore can be used by the local fauna. In this system, understory of native forests is replaced by cocoa trees, which are shaded by large old-growth trees. However, the persistence of native species in cocoa agroforests depends on local vegetation characteristics but also the landscape structure in which these systems are located. Here, we investigated the influence of landscape composition (i.e. amount of forest cover, cocoa agroforestry and cattle pasture) and local vegetation structure (i.e. number of native and cocoa trees, basal area of native trees and canopy closure) on understory birds in 18 cocoa agroforestry systems located in three regions in the Brazilian Atlantic forest, presenting distinct land use contexts. Specifically, we assessed the effects of these landscape and local features in predicting richness and abundance patterns of the entire community, and also in distinct ecological groups, such as forest-dependent and non-forest-dependent birds, and insectivores, frugivores, and omnivores. Using generalized linear models and Akaike information criterion, we observed lower species richness of complete community, non-forest and omnivorous birds in the most deforested region. Also, our findings demonstrated that cocoa agroforests integrated in more forested landscapes harbor greater richness and abundance of frugivorous birds. Conversely, the increase in cattle pasture amount at the landscape had a harsh effect on all bird groups evaluated. Regarding local vegetation, we observed that the increase of canopy closure leads to greater abundance of insectivorous birds in cocoa agroforestry systems. Similarly, abundance of non-forest species increased in agroforests with higher number of cocoa trees. Our study demonstrated that cocoa agroforestry systems can provide complementary habitats for many species, including forest birds, and therefore can mitigate the effects of habitat loss. However, this key benefit for bird conservation will be more effective when these agroforestry systems are located in more forested landscapes, with low amount of cattle pastures. Our findings therefore reinforce the alarming need to maintain and recover landscape-scale forest amount to ensure species persistence of birds in anthropogenic landscapes, even in those comprising biodiversity-friendly land uses such as cocoa agroforestry systems.

Biomass and carbon stocks of organic and conventional cocoa agroforests, Ghana

Cocoa production is a globally important commodity that has been a major driver of deforestation in humid tropical areas. Cocoa agroforestry systems have been credited for storing significant stocks of carbon potentially mitigating some of the negative impacts of cocoa production on ecosystem services but the impact of organic management on this potential is unclear, especially in Africa. We quantified cocoa and shade tree biomass, above and below ground and soil carbon stocks of 42 organic and 42 conventional cocoa agroforestry systems in Ghana (a globally important cocoa producing country) across three cocoa-age groups; young (≤ 15 years), mature (16–30 years) and old (≥ 31). We used the carbon stocks data to estimate the monetary value of the stored carbon in the two systems. Mean aboveground biomass C (Org. 41.3 ± 3.62 vs. Con. 22.9 ± 2.60 Mg C ha−1), belowground biomass C (Org. 7.8 ± 0.67 vs. Con. 4.2 ± 0.66 Mg C ha−1) and soil C stocks (Org. 59.7 ± 3.36 vs. Con. 49.7 ± 3.33 Mg C ha−1) were higher on organic farms compared to conventional farms. The dominant shade tree species on both organic (15 spp.) and conventional (15 spp.) stored more than 70 % of vegetation carbon stocks on both farm types. The estimated monetary value of the rate of CO2 equivalent of stored carbon by organic cocoa systems ranged from 74.58 US$ ha−1 yr−1 in old farms to 208.07 US$ ha−1 yr−1 in young farms compared to a range of 39.08 US$ ha−1 yr−1 in old farms to 99.60 US$ ha−1 yr−1 in young farms on conventional cocoa farms. The results show that organic cocoa agroforestry systems in our study area hold a greater potential to accumulate carbon and in addition benefit from carbon schemes than conventional cocoa agroforestry systems. Organic farms had higher shade tree diversity and richness which reflected the willingness of organic farmers to maintain/plant agroforestry trees. This indicate organic cocoa agroforestry system can help retain important ecosystem services within the cocoa production areas while providing some additional income to small holder cocoa farmers.

Biodiversity of the Cocoa Agroforests of the Bengamisa-Yangambi Forest Landscape in the Democratic Republic of the Congo (DRC)

Cocoa agroforestry has evolved into an accepted natural resource conservation strategy in the tropics. It is regularly proposed as one of the main uses for REDD+ projects (Reducing Emissions from Deforestation and forest Degradation and the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks in developing countries) in the Democratic Republic of the Congo. However, few studies have characterized the cocoa agroforestry systems in this country. Hence, this research proposes to determine the impact of distance from Kisangani (the unique city in the landscape) and land-use intensity on the floristic composition of cocoa agroforests in Bengamisa-Yangambi forest landscape in the Congo Basin. The results revealed that species diversity and density of plants associated with cocoa are influenced by the distance from Kisangani (the main city in the landscape and province). Farmers maintain/introduce trees that play one or more of several roles. They may host caterpillars, provide food, medicine, or timber, or deliver other functions such as providing shade to the cocoa tree. Farmers maintain plants with edible products (mainly oil palms) in their agroforests more than other plants. Thus, these agroforests play key roles in conserving the floristic diversity of degraded areas. As cocoa agroforestry has greater potential for production, biodiversity conservation, and environmental protection, it should be used to slow down or even stop deforestation and forest degradation.

Cocoa agroforestry systems versus monocultures: a multi-dimensional meta-analysis

Scientific knowledge, societal debates, and industry commitments around sustainable cocoa are increasing. Cocoa agroforestry systems are supposed to improve the sustainability of cocoa production. However, their combined agronomic, ecological, and socio-economic performance compared to monocultures is still largely unknown. Here we present a meta-analysis of 52 articles that directly compared cocoa agroforestry systems and monocultures. Using an inductive, multi-dimensional approach, we analyzed the differences in cocoa and total system yield, economic performance, soil chemical and physical properties, incidence of pests and diseases, potential for climate change mitigation and adaptation, and biodiversity conservation. Cocoa agroforestry systems outcompeted monocultures in most indicators. Cocoa yields in agroforestry systems were 25% lower than in monocultures, but total system yields were about ten times higher, contributing to food security and diversified incomes. This finding was supported by a similar profitability of both production systems. Cocoa agroforestry contributed to climate change mitigation by storing 2.5 times more carbon and to adaptation by lowering mean temperatures and buffering temperature extremes. We found no significant differences in relation to the main soil parameters. The effect of the type of production system on disease incidence depended on the fungal species. The few available studies comparing biodiversity showed a higher biodiversity in cocoa agroforestry systems. Increased and specific knowledge on local tree selections and local socio-economic and environmental conditions, as well as building and enabling alternative markets for agroforestry products, could contribute to further adoption and sustainability of cocoa agroforestry systems.

The role of shade trees in influencing farmers’ adoption of cocoa agroforestry systems: Insight from semi-deciduous rain forest agroecological zone of Ghana

Farmers growing desire for no shade cocoa system has reiterated the scepticism about the impact of research on farmers’ adoption of cocoa Agroforestry. In this study, we assess farmers’ perception about shade trees and how that influences their adoption of cocoa Agroforestry. Five cocoa growing communities in the Eastern Region of Ghana and 91 cocoa farmers were purposively sampled and interviewed. The result showed that the most desirable shade trees among the farmers were Spathodea campanulata, Terminalia superba, and Terminalia ivorensis while Alstonei boonei was the least desirable. About 87 % of farmers introduced shade trees at different stages of cocoa farm establishment while 13 % of farmers had existing trees at establishment. Farmers with less than 11 years farming experience and those with Senior High education kept the recommended number (15–18) of shade trees ha−1. Most farmers related the importance of shade trees to the good growth of cocoa associated crops (37 %) and as source of fodder (31 %), while higher cocoa yield and low education on the importance of shade trees were major reasons farmers removed shade trees. In conclusion, collaboration between farmers and other stakeholders in the cocoa sector is essential in reversing the growing hunger for no shaded cocoa system. This collaboration must focus on educating farmers on the importance of shade trees, and by providing money and agro-inputs support to farmers as impetus for the adoption of cocoa Agroforestry in Ghana.

Diversity of indigenous arbuscular mycorrhizal fungi in rhizosphere of upland rice (Oryza sativa L.) varieties in Southwest Nigeria

Diversity of indigenous arbuscular mycorrhizal fungi in rhizosphere of upland rice (Oryza sativa L.) varieties in Southwest Nigeria