Management Of Agroforestry Systems Research Articles

Nutrient Contribution and Carbon Sequestration of an Agroforestry System of Coffea canephora Cultivated by Conventional and Organic Management in the Ecuadorian Amazon

Agroforestry systems (AFSs) seek synergies that improve productivity, sustainability, and environmental benefits. This is achieved through the supplying of nutrients to the soil, carbon storage, and sequestration. In the Ecuadorian Amazon, Coffea canephora is planted together with leguminous, woody, forest, and secondary forest species, where the continuous incorporation of vegetative residues from shade species represents a substantial addition of nutrients within these systems. This study was carried out from 2018 to 2022 to determine the contribution of nutrients contained in the biomass and C sequestration in agroforestry systems of coffee with conventional (high use of agrochemicals) and organic (without the use of chemicals) management. The study was carried out with a randomized complete block design, using a factorial arrangement (2 × 4 with three replications). This arrangement included two types of systems (agroforestry and monoculture) and four agronomic management practices (high and medium for conventional, and intensive and low organic). The biomass and nutrient content were measured twice a year (every 180 days); in addition, the yield was also recorded. A multivariate and univariate analysis was used for data analysis through R and SAS software. After five years of evaluation, it was determined that the N, K, Ca, and Mg contents were higher in the agroforestry systems than the monocultures. In the AFSs, the highest nutrient content was obtained with the medium conventional and low organic agronomic management, while in the monocultures, it was obtained with the high and medium conventional management. In addition, at a soil depth of 20 cm, the total storage and CO2 were 38.12 and 139.8 t ha−1, respectively. The highest yields were obtained with conventional management in AFSs (1599 kg ha−1) and monoculture (1789.45 kg ha−1). Overall, AFSs showed a significant contribution of nutrients, such as N, K, Ca, and Mg, for coffee cultivation; moreover, yields were similar in the AFS and monoculture with both conventional and organic management, which is positive, since AFSs also contribute environmental benefits.

Assessing the cropland changes into agroforestry and its livelihood outcomes: Evidence from northern Bangladesh

This research was conducted to assess the scope and impact of the conversion of croplands into agroforestry orchards considering characterizing agroforestry growers, identify challenges they face during the transition process, and gather their recommended strategies to address these challenges.The investigation took place in Sadar and Biral upazila within Dinajpur district of northern part of Bangladesh. To establish a sample group, an updated roster of total 266 agroforestry growers was procured from the respective Upazila Agriculture Offices. Using a simple random sampling method, 80 growers were selected for participation in this study. Data was gathered through structured and pretested interview schedules administered to respondents between April 15th and May 15th, 2022. The study evaluated ten key attributes of agroforestry growers, encompassing factors like age, educational background, farm size, farming experience, family income, extension network engagement, agricultural knowledge, innovation inclination, marketing orientation, and technological attitude. The central focus of the study centered on the transition from croplands to agroforestry orchards. The study revealed that over the period spanning 1990 to 2022, agroforestry farmers in the study region converted cropland into orchards with varying extents, ranging from 13 % to 19.83 %. The substitution of predominant crops such as rice, maize, and wheat, along with minor crops like potatoes, vegetables, mustard, garlic, turmeric, and napier grass, marked the transition to agroforestry practices. Evaluating the consequences of this transition, approximately 60.00 % of growers perceived medium-level impacts on economic aspects, while 70.00 %, 61.25 %, and 58.75 % alleged the effects on environmental conditions, household food security, and social status, respectively as also moderately. Among the challenges faced during this shift, the most prominent was the difficulty in obtaining fair prices due to intermediary involvement. Conversely, elevated production costs were regarded as a lesser concern. Respondents put forth a variety of solutions, with the primary recommendation being the organization of enhanced training programs for farmers on scientific agroforestry systems management. In contrast, the concept of fostering appropriate coordination among agroforestry practitioners garnered less attention as a potential solution. Therefore, for farmer's enhanced benefit as well as for better environmental outputs and food security, agroforestry product marketing strategy should be strengthening using site specific policy and program.

Promoting Collaboration in Supporting the Sustainable Governance of Educational Forest Areas

Agroforestry is designed to offer benefits to communities and improve community welfare. This research focuses on collaborative governance theory that intends to understand the history and management of agroforestry systems in UB Forest and related issues during the transition from Perhutani management to Universitas Brawijaya. The purpose is to understand issues related to agroforestry policies and regulations from the central/local government. This research adopts and confirms the theory developed by Ansell and Gash regarding collaborative governance. Case studies, including interviews, observations, and documentation were used in this research. The Mcnabb model technique was used in data analysis. The results show that the natural conversion of forests into agricultural land causes many problems, such as decreased soil fertility, erosion, extinction of flora and fauna, floods, droughts, and even changes in the global environment. It can be concluded that there are still some issues related to communication and commitment to the process. UB Forest adheres to the ministerial decree and the three pillars of higher education, but other actors have not committed because there is no written regulation.

Management intensity affects insect pests and natural pest control on Arabica coffee in its native range

Abstract Agroforestry systems provide opportunities to reduce the trade‐off between agricultural production and biodiversity, for example by enhancing a diverse community of species potentially acting as natural pest control agents. While management of agroforestry systems is intensifying across the globe, we lack insights into the impact of management intensity on pest levels and natural pest control, especially along broad management gradients and as compared with natural forests. We assessed the impact of management intensity on major insect pests (the coffee blotch miner, the serpentine leaf miner, the coffee leaf skeletonizer and damage by other free‐feeding herbivores) and natural pest control by parasitoid wasps across sixty sites in the centre of origin of Arabica coffee in southwestern Ethiopia. Within this region, coffee is growing along a broad management gradient ranging from little or no management in the natural forest to intensively managed commercial plantations. In the wet season, pest levels were largely similar in the natural forest, semi‐forest and semi‐plantation systems, whereas pests reached outbreak densities in the most intensively managed plantation system. In contrast, management intensity did not significantly affect pest levels in the dry season. The insect pests differed in their seasonal dynamics, consistently declined with elevation and were largely unaffected by shade levels. Parasitism rate of the coffee blotch miner was lower, and the parasitoid community was distinct, in the most intensively managed plantation system. Synthesis and applications : Our findings support the hypothesis that the weaker top‐down control by parasitoids in the intensively managed plantation sites leads to higher pest levels, and that—at least for some pest species—there is a threshold in the effect of management intensity on pest levels and natural pest control. It is important to consider such non‐linear relationships to maintain or enhance the sustainability of agroforestry systems during management intensification. Overall, our findings highlight that ecological knowledge of natural pest control can be used to intensify production to improve the livelihood of smallholder farmers without jeopardizing natural pest control but only up to a certain point where it starts to deteriorate.

The effect of land management and organic matter inputs on bacterial population and soil nutrients across different types of agroforestry system

Abstract. Rinady MVP, Nuraini Y, Prayogo C, Arfarita N. 2023. The effect of land management and organic matter inputs on bacterial population and soil nutrients across different types of agroforestry system. Biodiversitas 24: 1333-1345. Different management of agroforestry systems changes crop composition and growth. This will affect organic matter inputs that become the source of food and energy for soil microorganisms. The soil organisms themself play an important role in amplifying soil biogeochemical processes and regulating soil reactions. This process allows the nutrients to be released into the soil and absorbed by the crop. This study aimed to examine the abundance of soil bacterial population and the changes in soil chemical properties (soil pH, total soil organic carbon (C), and total soil N (Nitrogen) under different land management and organic matter inputs. The determination of total organic C and total soil N was used by Walkey and Black and Kjedahl methods. Total Plate Count (TPC) techniques were employed to measure Total Bacteria Population (TBP) and Total Cellulolytic Bacteria (TCB). The Randomized Complete Block Design was used along with the 5% Tukey's test to examine the significant effect of the treatments. These treatments consisted of various agroforestry system as follow: (i) pine-coffee agroforestry system (PK), (ii) pine-banana agroforestry system (PPs), (iii) pine-cardamom agroforestry system (PR), (iv) pine-vegetable agroforestry system (PS), (v) mixed garden (KC), and (vi) citrus (LJ). Each treatment was repeated four times to obtain 24 experimental plots using a size of 20 m x 20 m. The results showed that the highest organic C and N content was obtained at the PK (agroforestry of pine at 41 years and coffee at 11 years old) plot, which was about 6.64% and 0.56%. Those parameters strongly correspond to the greatest soil bacteria population and soil cellulolytic bacteria population at the value of 1,71 x 105 CFU/g and 4,24 x 104 CFU/g, resulting from the greatest quantity of in-situ litter accumulation at PK plot to reach about 201.35 g. The dry weight value of litter in situ at the PK plot is greater than that of the PS and LJ plots by 81% and 87%. A power equation followed the relationship between soil organic C and the total bacteria population. A similar trend has been observed between total soil Nitrogen and total bacteria population. We concluded that changes in different management could affect soil chemical conditions and the changes in the total population of soil bacteria and cellulolytic soil bacteria.

Effect of neighbouring perennials on cocoa tree pod production in complex agroforestry systems in Cameroon

Agroforestry systems (AFS) are gaining major interest in cocoa producing countries. However, the analysis of competition effects in multispecific complex agricultural systems remains a key lock-in preventing both (i) a thorough understanding of resource partitioning, and (ii) the co-design of spatial patterns and management of cocoa AFS (cAFS) minimising competition. We sampled 48 cAFS 1000 m² plots in Central Cameroon and used an individual based approach to analyse the effect neighbouring tree community composition had on coca tree pod production. First, we determined the distance up to which each neighbouring tree influenced the production of a given cocoa tree and checked for the significance and the magnitude of this effect. We then explored the trade-offs between cocoa tree production and the abundance of associated trees. Our results first underline a significant intra-specific competition within the cocoa tree populations studied, which would need to be thinned down to 800–1100 individuals per ha. We also found a general negative effect of associated trees kept or grown for their fruits (e.g. mango, traditional species, citrus trees). Those effects were stronger when the trees were positioned between 6 and 11 m away from the cocoa trees. These trees clearly impaired pod production, especially for small diameter cocoa trees. Palm trees, however, had a positive effect on cocoa pod production, with suitable densities modelled ranging from 0 to 240 individuals per ha. Finally, we found both positive and negative effects of associated forest trees on cocoa pod production, which varied with the distance separating them from the cocoa trees and the size of the cocoa trees. Overall, our analyses show that cocoa production in complex cAFS is influenced both by intra- and inter-specific interactions while it remains difficult to distinguish between potential intertwined effects and resource limitations.

Tree Effects on Coffee Leaf Rust at Field and Landscape Scales.

Although integrating trees into agricultural systems (i.e., agroforestry systems) provides many valuable ecosystem services, the trees can also interact with plant diseases. We demonstrate that a detailed understanding of how plant diseases interact with trees in agroforestry systems is necessary to identify key tree canopy characteristics, leaf traits, spatial arrangements, and management options that can help control plant diseases at different spatial scales. We focus our analysis on how trees affect coffee leaf rust, a major disease affecting one of the world's most significant crop commodities. We show that trees can both promote and discourage the development of coffee leaf rust at the plot scale via microclimate modifications in the understory. Based on our understanding of the role of tree characteristics in shaping the microclimate, we identify several canopy characteristics and leaf traits that can help manage coffee leaf rust at the plot scale: namely, thin canopies with high openness, short base height, horizontal branching, and small, dentate leaves. In contrast, at the edge of coffee farms, having large trees with high canopy volume and small, thick, waxy leaves is more useful to reduce throughflow wind speeds and intercept the airborne dispersal of urediniospores, an important consideration to control disease at the landscape scale. Seasonal pruning can help shape trees into the desired form, and trees can be spatially arranged to optimize desired effects. This case study demonstrates the added value of combining process-based epidemiology studies with functional trait ecology to improve disease management in agroforestry systems.

Agroforestry management systems through landscape-life scape integration: A case study in Gowa, Indonesia

Abstract. Hasannudin DAL, Nurrochmat DR, Ekayani M. 2022. Agroforestry management systems through landscape-life scape integration: A case study in Gowa, Indonesia. Biodiversitas 23: 1864-1874. Agroforestry has a potentially important role in increasing farmers' income and sustainable landscape management. The need to increase income from a community with limited land area, resulting in indiscriminate deforestation and shifting cultivation, has accelerated soil erosion. This study addresses the problem by evaluating land use and land cover change structure and prediction, providing plant types' preferences for agroforestry systems based on social, business feasibility, and ecological suitability. This study was conducted in Bontolerung Village, part of the KPH Jeneberang 1's working area, Tinggimoncong Sub-district, Gowa District, South Sulawesi Province, Indonesia. The data was collected from January to March 2021 using a snowball-purposive sampling method. The analysis data used land use and land cover change, land management patterns, cost and revenue, household expenditure and income, financial feasibility -Net present value (NPV), Benefit-cost ratio (BCR), and Internal rate of return (IRR), and ecological suitability (invasive series). The study finds that forest cover losses are 17% from 2010-2020 and converted into agricultural land. The agroforestry patterns of coffee, coffee-cloves, and coffee-cloves-iles-iles are feasible to cultivate following the NPV, BCR, and IRR criteria. Agroforestry systems contributed 26% to farmer household income. The value shows a low percentage compared to the non-agroforestry income (74%). The coffee-cloves agroforests show the highest gains with an average annual income of IDR 43,017,192 (US$ 3,024.9). This study promotes using agroforestry to reforest the existing degraded lands. Agroforestry systems offer great potential for environmental conservation and contribution to human well-being.

Growth and Yield of Schizolobium parahyba var. amazonicum According to Soil Management in Agroforestry Systems: A Case Study in the Brazilian Amazon

Studies on applying of soil management practices in the management of paricá and the effects on growth and yield are essential to auxiliary its cultivation and would allow us to inform management and conservation decisions to reconciliate biodiversity, wellbeing, and sustainable production. This case study aimed to evaluate the growth and yield of paricá at different soil management practices, including consortium with an agricultural production, in the Brazilian Amazon. Paricá was implanted, consorted with soybean in the first year, and maize in the second, in a 5 × 2 m spacing. The treatments T1 = subsoiling, basal dressing, top-dressing, inoculation of microorganisms and consortium with soybean/maize were applied. In T2, T3, T4, and T5, we applied the same practices of T1, except subsoiling (T2), basal dressing (T3), top-dressing (T4) and inoculation of microorganisms (T5). T6 was the control, which used none of these practices, including the consortium with soybean/maize. The results indicate that the highest rate of plant survival occurred in T2, while T3 and T4 promoted greater intraspecific competition, compromising the growth in dbh and the yield (m3 ha−1) of plants in future ages. Growth in dbh and th and the yield of plants in the soybean/maize consortium period was higher in T2 and T6. In future ages, the dbh and yield of plants demonstrated higher growth trends in T6, T1, and T5. Agroforestry practices of soil management influence the growth and yield of paricá plants. However, there is a tendency for greater growth and yield for paricá plants cultivated in the absence of agroforestry practices for soil management proposed in this case study. When opting for AFS (paricá intercropped with soybean and maize), it is recommended for paricá a subsoiling, fertilization, and inoculation of microorganisms.

Study of agroforestry system management in Pitumpanua District, Wajo Regency

This study aims to determine the management of agroforestry systems, structure, and composition of agroforestry constituent components and agroforestry constituent components’ income. This research was conducted in October - November 2019 in Pitumpanua district, Wajo Regency. The method used is purposive sampling with respondents farmers who have a land area of ⩾ 0.5 ha and implement agroforestry systems. To determine the volume of wood, structure, and composition of plant species, we created 15 sample plots. To find out the form of agroforestry management and productivity, 30 respondents were interviewed. The data were processed and analyzed using descriptive and quantitative methods. The results showed the management conducted in three villages in the Pitumpanua district is land preparation, seed sourcing, planting, crop maintenance, and harvesting. The composition of plant species contained in each plot as many as 13 species of plants. Productivity can be known after analyzing cost, revenue, and income. Farmers’income in Jauh Pandang Village is higher at Rp. 39,880,341/ha/year, compared to marannu village farmers’ income of Rp. 31,415,334/ha/year and farmers’ income in Ale Lebbae Village is Rp. 28,718,248/ha/year.

Species diversity, composition, structure and management in agroforestry systems: the case of Kachabira district, Southern Ethiopia

Agroforestry is increasingly being identified as an integrated land use enhancing plant diversity while reducing habitat loss and fragmentation. This paper examined species diversity, composition, structure and management in agroforestry systems. Two Kebeles (Kachabira and Mesafe) were purposively selected for this study. Then, farmers who dominantly practiced agroforestry practices such as home garden, parkland and live fence were stratified based on wealth categories. Ten percent of the sample households were randomly selected from each wealth category. Accordingly, a total of 83 households were selected. Inventories of plant species were done by sampling one plot of each farm management type. A total of 59 plant species, belonging to 56 genera and 36 families were recorded across the home gardens, parklands and live fences in the study area. Among the plant species, trees constituted 42%, shrubs 27%, herbs 29% and climber 2%. From recorded plant species, 66% were native and the remainders 34% were introduced species. From the native species recorded in this study, Lippia adoensis and Millettia ferruginea were endemic to Ethiopia. The mean Shannon diversity index of rich, medium and poor households in the three different agroforestry practices were 1.75, 1.57 and 1.62 in home garden, 0.36, 0.30 and 0.49 in parkland and 0.84, 0.99 and 1.00 in live fence respectively. The largest tree basal area was recorded in the live fence (14.7 m2ha-1), followed by home garden and parkland. The study revealed that agroforestry plays an important role in the conservation of biodiversity, and also by providing food, income and a wide range of other products such as fuel wood, construction material, fodder, spices and medicinal plants. Farm household landholding size, species preference and management found to be the most important influencing factors that affect the diversity of plant species. Further detailed study of explicit examining of the factors such as socio-ecological effects that determine species diversity and the contribution of different functional groups to livelihood is needed to fully understand the agroforestry system.

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.

Estrutura e síndromes de dispersão da vegetação arbórea em floresta nativa e agrofloresta, na Amazônia Meridional: Structure and dispersal syndromes of forest and agroforest

The choice of native species used in the management of agroforestry systems for the recovery of anthropized environments, are fundamental for maintaining biodiversity and ecological processes. In this study, we evaluated the structural complexity and diversity of plants in a teak agroforestry, compared to a native forest tangent to the planted area. Thus, we set up 33 plots in the area of ​​native forest and 24 in agroforestry, both with dimensions of 10 × 10 m, at Fazenda Sao Nicolau, Cotriguacu, Mato Grosso, Brazil. We collected data on the structure of vegetation and calculated the descriptive phytosociological parameters of the community structure. We used i) PCoA to evaluate the floristic similarity between native forest and agroforestry, ii) GLM to determine the influence of the canopy opening on the vegetation structure, and iii) ANOVA to analyze the structural characteristics by dispersion syndrome. We registered 395 tree individuals belonging to 98 species and 35 families, including the exotic species Tectona grandis. We considered abundance and the basal area in relation to the dispersion syndrome, where we noticed, the zoocoria significantly higher when compared to anemocoria and autocoria. Thus, we consider the zoochoric dispersion syndrome as a factor that best explains the relationship between the types of forests in the Southern Amazon.

Diversity of saproxylic beetle communities in chestnut agroforestry systems

Chestnut (Castanea sativa Mill.) has been exploited over the centuries for different uses. Nowadays, chestnut is mostly managed as coppice or orchard, creating a matrix of different forest structures. In particular, saproxylic species may provide information to correlate forest naturalness with stand structure. In this study, we evaluated how different management methods might influence the diversity of beetles hosted in chestnut agroforestry systems. Three management options were considered: young and mature coppice stands, and the traditional fruit orchard. Microhabitats occurring on veteran trees were also surveyed to investigate their effect on saproxylic communities, in the fruit orchard. The study area is located in Southern Italy, Aspromonte National Park, where Coleoptera were collected using window flight traps and the stand structural traits were also quantified. In the fruit orchard, a census of the occurring microhabitats was also realized. We used the following diversity indeces (α-diversity) to assess the state of conservation of the analysed forests: (i) Shannon Index; (ii) Margalef’s Richness index; (iii) Equitability index; (iv) Dominance index. Results revealed that forest management have a fundamental role in influencing the diversity of Coleoptera communities and saproxylic beetles. A lower species richness was observed in the mature coppice in comparison with the young coppice and fruit orchard. Nevertheless, these agroforestry systems, reflecting differentiated structural traits, allowed the development of highly specialized and threatened species (34.3% included in IUCN risk categories), with important contribution to conservation of biodiversity in the rural landscape. Finally, the abundance and diversity of microhabitats in the traditional fruit orchard had positive effects on many saproxylic beetle families. These beetle communities, particularly saproxylic species, can be used as excellent bioindicators in actively managed agroforestry systems, suggesting sustainable forest management options for chestnut, while the conservation of veteran trees rich in microhabitats can be considered fundamental for preserving many endangered insects.

Landscape and Thermodynamic Justification for The Application of Intelligent Technologies of Agroforestry Systems Management

Landscape and Thermodynamic Justification for The Application of Intelligent Technologies of Agroforestry Systems Management

Short-term soil physical quality improvements promoted by an agroforestry system

Concerns with environmental sustainability have promoted adoption of conservationist practices in agricultural production, mainly focused on soil quality preservation or recovery. The aim of this study was evaluating short-term soil physical quality improvements under agroforestry system management in Southern Brazil. The agroforestry system was implemented in 2013 in an Ultisol with Sandy Loam texture. Rows of agroforestry system (AFS-R) were composed by biomass producer trees intercalated with wood and fruit producer trees while in the inter-rows (AFS-IR) perennial sub-shrub, perennial grass, and summer and winter green manure annual species were implanted. Soil under native forest was used as control. Soil samples in the 0.0–0.1; 0.1–0.2 and 0.2–0.4 m depths were collected for the determination of physical attributes and the total organic carbon content in 2015, 2016 and 2017. Bulk density decreased about 9% (AFS-R) and 6% (AFS-IR) in 0.0–0.1 m between 2015 and 2017. Total porosity increased over time only in AFS-R, at a rate of 0.025 m3 m−3 year−1. The total organic carbon content of AFS increased over time only in the 0.0–0.1 m layer, although remained up to 35% less in relation to the native forest. The agroforestry system resulted in consistent improvements of several soil physical attributes over short time, particularly in rows with arboreal plants, highlighting the role of diversified tree root systems and plant residues accumulation, which implied a rapid improvement in soil quality. In this context, long-term studies with agroforestry systems are crucial to understand the benefits on soil quality.

Leaf trait variation and decomposition in short-rotation woody biomass crops under agroforestry management

The integration of trees into agricultural landscapes has a strong influence on plant-soil interactions, with major impacts on rates of nutrient cycling across multiple spatial scales. Shifts in abiotic conditions owing to agroforestry practices, such as changes in soil nutrient and microclimatic conditions, are commonly identified as primary mechanisms for these changes. Yet agroforestry systems are also likely to influence litter decomposition rates through their influence on morphological and chemical traits of crop leaves and residues. However, explicit evaluations of how agroforestry management results in intraspecific leaf trait plasticity, and how this variation then links with litter decomposition, remain sparse. Using a 30-year-old agroforestry system intercropped with short-rotation willow (Salix dasyclados), we i) examined the effects of agroforestry management (i.e. N2-fixing trees vs. non N2-fixing trees vs. monoculture) and distance from tree row on key crop (willow) leaf morphological (i.e. leaf area, specific-leaf area [SLA]) and chemical (leaf carbon (C) and nitrogen (N) concentration) traits, and then assessed ii) how this intraspecific leaf trait variability influenced decomposition rates. Willow leaves within agroforestry treatments exhibited significantly greater leaf area (p = 0.01), SLA (p = 0.002), and leaf N (p = 0.001) than willow leaves in monoculture. Following a 56-day incubation, willow leaves from agroforestry treatments did not decompose more quickly than those in the monoculture. Our results indicate high intraspecific variation in willow leaf traits owing to agroforestry management. However, intraspecific variation in willow leaf traits did not correspond to statistically significant differences in decomposition rates. We show that variation in willow traits near tree rows in agroforestry systems translates into limited variability in agroecosystems processes such as litter decomposition (as compared to monoculture arrangements). Our results have implications for optimal nutrient management in agroforestry systems.

Cacao agroforestry management systems effects on soil fungi diversity in the Peruvian Amazon

Abstract Cacao agroforestry system provides productive land use and preserves the best conditions for physical, chemical and biological properties of tropical soils in cocoa tropical region of the world. We evaluated the impact of changing a 30-year-old native secondary forest to two cacao agroforestry systems on soil fungal diversity. The cacao agroforestry systems adapted were: an improved natural agroforestry system (INAS) where trees without economic value were selectively removed to provide 50% shade; and an improved traditional agroforestry system (ITAS) where all native trees were cut and burnt in the location. In both systems, new economically valuable trees were planted. In these management systems, plots of 10 cacao genotypes and one plot with a spontaneous cacao hybrid were selected for soil sampling. In each plot, soil samples were randomly collected at 0–20 cm depth, immediately after the trees were planted (2004) and at the end of 2010; each sample was divided in two, one part for soil characterization by conventional chemical analytical methods and the other for soil fungal analysis using the plate dilution method. Soil fungi were identified by appropriate keys and grouped according to their functionality as potential biocontrol, plant pathogenic, facultative or saprophytic fungi; the structure of fungal communities was analyzed by population, richness and Shannon and Simpson indices. Fungal diversity varied significantly during the years of study, at all soil depths and under the agroforestry systems assessed. The fungal communities showed significant changes due to soil management influenced by INAS and ITAS, and mainly after burning of native vegetation in ITAS. Overall higher abundance of soil fungal communities were observed in ITAS than in INAS. In both systems, differential changes in soil physical and chemical properties under cacao also could have been a contributing factor in the fungal diversity and functional groups observed.

Trichoderma en la Argentina: Estado del arte

Las metodologias que se aplican para manejar los sistemas agricolas y agroforestales tienen efectos notables en la produccion de alimentos y en la conservacion de la biodiversidad. Las enfermedades que causan los hongos fitopatogenos son uno de los problemas criticos en la agricultura argentina. A partir de la necesidad de encontrar mecanismos que eleven la productividad del campo, en los ultimos anos se intensifico la busqueda de estrategias de control de enfermedades agricolas que sean alternativas al control quimico, buscando, ademas, disminuir los riesgos ambientales y sanitarios derivados de este. El hongo Trichoderma es uno de los agentes que mas se usan en los programas de control biologico como reguladores de hongos fitopatogenos. Esta revision tiene como objetivo realizar una compilacion de toda la informacion disponible respecto al estado del arte de Trichoderma como controlador biologico en la Argentina, con el fin de referenciar diferentes instituciones del pais que centralizan a este hongo en sus investigaciones. Cerca de 70 grupos de universidades e institutos de investigacion describieron aproximadamente diez especies diferentes de Trichoderma con capacidad antagonista, se estudiaron alrededor de 35 cultivos y 40 patogenos. La especie de Trichoderma mas utilizada como agente de control biologico es Trichoderma harzianum, seguida por Trichoderma koningii y Trichoderma viride. Actualmente, en el mercado argentino existen cerca de 14 bioproductos cuyo principio activo son cepas de Trichoderma. Las crecientes iniciativas de las instituciones nacionales sobre estos estudios son basicas para el desarrollo de tecnologias innovadoras y para lograr una agricultura mas productiva y ambientalmente sostenible en el pais.https://doi.org/10.25260/EA.20.30.1.0.945

Agroforestry Management Systems Drive the Composition, Diversity, and Function of Fungal and Bacterial Endophyte Communities in Theobroma Cacao Leaves.

Cacao (Theobroma cacao L.) is one of the most economically important crops worldwide. Despite the important role of endophytes for plant growth and health, very little is known about the effect of agroforestry management systems on the endophyte communities of T. cacao. To close this knowledge gap, we investigated the diversity, community composition, and function of bacterial and fungal endophytes in the leaves of T. cacao trees growing in five major cacao-growing regions in the central region of Cameroon using DNA metabarcoding. Fungal but not bacterial alpha diversity measures differed significantly between the agroforestry management systems. Interestingly, less managed home-garden cacao forests harbored the lowest fungal richness and diversity. Our results suggest that the composition of bacterial and fungal endophyte communities is predominantly affected by agroforestry management systems and, to a lesser extent, by environmental properties. The core microbiome detected comprised important fungal phytopathogens, such as Lasiodiplodia species. Several predicted pathways of bacterial endophytes and functional guilds of fungal endophytes differed between the agroforest systems which might be attributed to bacteria and fungi specifically associated with a single agroforest. Our results provide the basis for future studies on foliar fungal and bacterial endophytes of T. cacao and their responsiveness towards agroforestry management systems.