Landscape disruption in a fragmented world: A critical global analysis.

Managing shade trees, balancing trade-offs: Effects of shade-tree density on economic performance of Brazilian cocoa agroforests

This study extends the Hi-sAFe agroforestry model by incorporating the effects of elevated atmospheric CO2 on tree growth. Hi-sAFe is a process-based biophysical model that represents tree-crop interactions, but until now lacked a mechanism to simulate CO2-driven physiological responses of trees. We introduced CO2 sensitivity into the Light Use Efficiency (LUE) module and simulated the growth of Juglans nigra (black walnut) under current and future climate conditions (550ppm CO2, + 3°C, - 10% precipitation). Elevated CO2 increased tree height, diameter and root development in both forestry and agroforestry systems, but responses were stronger and more persistent in forestry. In agroforestry, CO2 effects were more variable over time and were strongly modulated by competition with crops, while belowground responses indicated greater root system plasticity. Climate change reduced tree growth in both systems, but CO2 partially offset these effects, particularly in forestry. These results demonstrated the importance of explicitly representing CO2 fertilisation in agroforestry models to realistically capture vegetation-climate interactions and assess the resilience of tree-crop systems under global change.

ABSTRACT Research shows the use of trees by farmers in agroforestry systems improves household nutrition consistent with local culture and food traditions. Additionally, it enhances climate change adaptation while contributing to environmentally friendly agricultural products. Nonetheless, some scientists argue that trees reduce soil moisture content in agricultural settings and that associated water demand could effectively compete with crops over limited available moisture. This research explored these competing claims in the context of Burkina Faso through the lens of farmer managed natural regeneration (FMNR). To assess FMNR’s impacts on soil moisture, a citizen science approach was used to collect soil matric potential data and measure crop yield near and away from trees using the crop-cutting technique. Results demonstrate that FMNR increases soil water availability and crop yield. Trees significantly increased soil moisture throughout the growing season, and crop yields were consistently higher in the canopy zone compared to outside it. These findings highlight FMNR as a sustainable strategy for managing water resources and boosting agricultural productivity. Beyond improving resilience to climate variability, FMNR contributes to addressing food insecurity and water scarcity in Burkina Faso, underscoring its importance as a nature-based solution for sustainable development.

Intercropping can reshape the rhizosphere microbiome, but how specific companion plants influence nutrient cycling and host growth remains unclear. We proposed that intercropping poplar with medicinal plants creates distinct rhizosphere niches that select for microbial communities with distinct​ functional potential, thereby improving tree nutrition. Intercropping significantly promoted poplar growth, with increases in diameter at breast height (DBH) of 15.33%, 14.3%, and 15.23% in systems with Anemarrhena asphodeloides, Belamcanda chinensis, and Saposhnikovia divaricata, respectively. Intercropping did not change microbial alpha diversity but led to plant-specific shifts in beta diversity with clear seasonal dynamics. Metagenomic analyses revealed corresponding shifts in the functional potential of microbial communities related to carbon (C) and phosphorus (P) cycling, including genes such as frdC, aldB, ppk2, and phnH. Intercropping, particularly with S. divaricata, was associated with an increased genetic potential for microbial C metabolism and​ a heightened potential for P solubilization. These co-occurring shifts in genetic potential were correlated with greater P accumulation in poplar leaves. Network analysis showed distinct temporal microbial co-occurrence patterns across intercropping treatments, with A. asphodeloides supporting the most interconnected community linked to P mobilization. Three bacterial genera (Priestia, Pseudomonas, Acinetobacter) were strongly associated with key soil nutrient pools. Re-inoculation experiments confirmed their functional roles: Priestia sp. increased N and P retention in the rhizosphere; Pseudomonas sp. promoted plant growth, suggesting a role in​ stimulating plant secondary metabolism; and Acinetobacter sp. enhanced organic C mineralization. Intercropping with specific medicinal plants structures the rhizosphere microbiome through niche differentiation. This restructuring leads to distinct patterns of microbial functional potential, centered on C and P metabolism, which correlate with improved poplar nutrient acquisition and growth. Our findings, integrating metagenomic inference with experimental validation, provide a framework for selecting companion plants to steer the rhizosphere microbiome toward beneficial functional outcomes in agroforestry systems. Video Abstract.

Metallic trace element concentrations, vertical patterns and environmental implications in soils under the "cabruca" agroforestry system of Brazil's largest cocoa-producing region.

The development of under-forest economy within agroforestry systems can enhance the efficiency of land and forest resource utilization, protect the ecological environment, and promote the sustainable development of forests. Forest understory American ginseng (Panax quinquefolius L.) often experiences spatial variability in light availability. However, the impact of light intensity under reduced spatial heterogeneity on soil microenvironments and the regulation of plant physiological traits to promote P. quinquefolius growth remains insufficiently explored. This study adopts field experiments in forest ecosystems to explore how light intensity influences P. quinquefolius physiology, soil biochemical properties, and microbial communities under reduced light spatial heterogeneity. The results indicate that, under reduced spatial heterogeneity with a light transmittance of 13.1%, P. quinquefolius exhibits coordinated physiological responses. The 13.1% light transmittance treatment decreases hydrogen peroxide content, while increasing net photosynthetic rate and chlorophyll content. These changes further improve root dry weight, which is significantly higher than that under 0.7%, 6.4%, and 19.8% light transmittance (with increases of 600.0%, 50.0%, and 5.0%, respectively). Additionally, soil urease activity, pH, and alkali-hydrolyzable nitrogen content are elevated, along with the relative abundance of pH-related microorganisms (e.g., unclassified_Leotiomycetes) and denitrifying bacteria (e.g., unclassified_Gemmatimonadaceae, Anaeromyxobacter, and Bradyrhizobium). The results of the Partial least squares path modeling analysis show that under reduced spatial light heterogeneity in the agroforestry system, light intensity directly promotes the growth of P. quinquefolius by modulating its physiological characteristics. Furthermore, light intensity indirectly fosters the growth of P. quinquefolius by improving soil biological properties (Urease, Sucrase, Catalase, Dehydrogenase, Acid phosphatase) and chemical properties (pH, Alkali-hydrolyzable nitrogen, Available potassium) through the regulation of its physiological characteristics. In conclusion, the optimal light transmittance for P. quinquefolius growth under reduced spatial heterogeneity is 13.1%. These findings offer practical insights for managing P. quinquefolius cultivation in forest ecosystems, contributing to the sustainable development of agroforestry systems.

Subsistence agriculture in tropical smallholder farming systems of eastern Africa faces persistent productivity challenges due to low soil fertility, limited inputs, and increasing climate variability. Agroforestry can offer a sustainable strategy for smallholder systems by enhancing soil quality and influencing arbuscular mycorrhizal fungi (AMF) community composition in crop root systems. Using a canopy-based radial sampling design, we assessed the influence of Mangifera indica (mango) trees on soil properties and AMF communities in maize and cassava in southern Ethiopia. Illumina MiSeq sequencing identified 908 AMF operational taxonomic units (OTUs) from 7 families, dominated by Glomeraceae. While soil properties, including pH, total nitrogen (TN), organic carbon, and potassium, were significantly affected by the distance from mango trunks (p < 0.001), this was not the case for AMF community composition and AMF richness and diversity. Host identity, rather than distance from the mango trees, was the primary driver of AMF community composition, with distinct and host-specific assemblages in mango, maize, and cassava roots (p < 0.001). Soil nutrients influenced AMF diversity differently across host plants (p < 0.05). In maize-mango systems, TN positively affected observed richness (Sobs) and Shannon diversity (N1), whereas Olsen P negatively affected N1 and Simpson diversity (N2). In cassava-mango systems, TN increased Sobs, and Olsen P positively influenced expected richness (Sexp). Overall, these findings suggest that improvements in soil fertility associated with mango-based agroforestry systems do not necessarily translate into corresponding changes in crop-associated AMF community composition and diversity. Without demonstrating direct benefits, we at least show that mango can be effectively integrated into smallholder maize and cassava production without compromising the AMF communities, while enhancing key soil fertility indicators. Maintaining adequate nitrogen levels while avoiding excessive phosphorus inputs may help sustain stable AMF communities in agroforestry systems.

Sandalwood (Santalum album L.), a highly valued hemi-parasitic tree, depends on host plants for nutrient acquisition, particularly under abiotic stress. However, the influence of host species on sandalwood's free amino acid (FAA) profiles under water deficit stress remains poorly understood. This study investigated how 11 host species modulate FAA composition in sandalwood roots during water deficit stress, aiming to identify host-specific metabolic adaptations that enhance stress resilience. LC-MS/MS analysis revealed significant host-dependent variations in FAA profiles. Pongamia pinnata association led to the highest accumulation of aspartic acid (7.28µg g- 1 FW), glutamic acid (13.87µg g- 1 FW), and lysine (67.11µg g- 1 FW), while Sesbania grandiflora resulted in minimal arginine (0.55µg g- 1 FW). Acacia nilotica and Punica granatum enhanced physiological resilience, with higher chlorophyll content (5.57µg mg- 1 FW), relative water content (62.8%), and proline levels (18.38µg g- 1 FW). Principal component analysis (69.7% variance explained) highlighted arginine, lysine, and histidine as key contributors to metabolic shifts under stress. Hierarchical clustering further confirmed host-specific FAA patterns, with Pongamia pinnata and nitrogen-fixing hosts promoting stress-responsive amino acids. Host selection strongly influences sandalwood's drought tolerance. Pongamia pinnata, Dalbergia sissoo, and Punica granatum enhance nitrogen metabolism, amino acid accumulation, and physiological traits under stress. These findings offer a practical, science-based strategy for improving sandalwood resilience in semi-arid regions through climate-smart host selection in agroforestry systems.

Shade-driven morpho-physiological plasticity buffers light-water co-limitation in Euterpe precatoria under rainfed field conditions.

Agroforestry systems (AFS), which integrate trees into agricultural landscapes, offer a promising strategy for climate change mitigation and biodiversity restoration. The trees can access additional resources, improving soil functions and contributing to soil regeneration through increased organic matter inputs. However, evidence is scattered and thus hindering unified global quantification of impacts. Here, we present the first bias-adjusted global quantitative synthesis of agroforestry effects on distinct soil and water attributes, drawing on 1590 primary studies summarized in 26 meta-analyses. We evaluated each meta-analysis against 16 standardized quality criteria. Less than half of the meta-analyses met > 75% of these criteria, while most did not weigh effect-sizes or assess heterogeneity and publication bias. We quantified primary studies overlap, finding an overall redundancy of 18% across all soil parameters, most of which arise from studies reporting on soil carbon. Accounting for meta-analysis quality and bias, AFS tend to increase soil organic carbon by 20%, improve chemical soil quality by 59%, physical soil quality by 22%, and enhance water regulation by 71%. Biological soil quality (86%), nutrient leaching reduction (67%), and erosion control (6%) also benefit from AFS, though with higher heterogeneity. Evidence is extensive for soil organic carbon and chemical properties (73% of studies), whereas it remains limited for AFS effects on biological (< 12%), physical (< 19%), and water-regulation traits (< 27%). 58% of meta-analyses report no details at all on system characteristics, such as stand age, species diversity, or tree density, limiting the identification of AFS management practices that maximize soil health attributes and highlight the need for standardized definitions of agroforestry and consistent sampling protocols. By systematically evaluating meta-analysis quality and study overlap, this synthesis provides a robust framework to distinguish reliable from uncertain outcomes and demonstrates the capacity of agroforestry to deliver multifunctional benefits, particularly regarding soil health.

Abstract In northwestern Vietnam, agroforestry is promoted to enhance environmental sustainability and support livelihoods, especially in resource-constrained situations. However, farmers adapt agroforestry in diverse ways, and there is still limited structured understanding of how differences in farm resources and configurations shape adoption patterns and support needs. Lack of knowledge about adoption patterns limits the design of cost-effective interventions. To fill this gap, we employed a participatory approach to develop a farm typology that links farm structure, agroforestry adoption patterns and group-specific constraints. Survey data from 101 households were analyzed using archetype analysis to identify distinct farm profiles. These profiles were validated through a series of farmer workshops to explore group-specific constraints and support needs. The archetype analysis identified three distinct agroforestry archetypes, each reflecting unique resource constraints. Archetype 1 and Archetype 2 both represent small-scale farmers with limited agricultural labor and diversified livelihood activities, but they differ in land configuration: Archetype 1 farmers manage more consolidated land and maintain high crop and tree diversity, whereas Archetype 2 farmers operate highly fragmented, small plots with limited potential to diversify. Archetype 3 farmers operate the largest farms among the three groups; they rely on annual crops and show the lowest agroforestry adoption level, with moderate species diversity in their agroforestry systems. Across archetypes, farmers emphasized needs for market access, as well as financial support for production inputs, tree seedlings and irrigation systems, system diversification and technical knowledge. Yet the rationale for these needs differed across groups. Our study is novel in combining data-driven archetype analysis with participatory validation to generate an action-oriented understanding of farm heterogeneity. The results show that support strategies should not only respond to common needs but also to the distinct constraints shaping agroforestry adoption across different farm contexts, highlighting the importance of context-specific, constraint-aware agroforestry policy and extension.

This study examines the socio-economic and environmental impacts of coffee-based agroforestry systems (AFS) in the Despagne community, Haute Voldrogue, Jérémie, Republic of Haiti, an area highly vulnerable to climate change and environmental degradation. Using a mixed and participatory research approach that combines household surveys, focus group discussions, and field observations, the study highlights the critical role of diversified agroforestry systems in promoting ecological restoration, strengthening food security, and enhancing income diversification among rural households. Results indicate that farmers’ monthly incomes range from 10,000 to 75,000 HTG, depending on land size, crop diversity, and market access. Agroforestry plots integrating coffee with bananas, yams, vegetables, and various fruit trees significantly contribute to soil fertility restoration, improved moisture retention, and biodiversity conservation. These diversified systems also reduce vulnerability to climate variability by stabilizing yields and providing multiple sources of food and income throughout the year. However, several structural challenges persist. The predominance of older producers aged between 40 and 65 years, limited youth involvement in agriculture, weak extension services, and geographical isolation continue to hinder long-term sustainability and access to profitable markets. In addition, climate instability, recurrent soil erosion, and the spread of coffee leaf rust disease further exacerbate production risks and threaten farmers’ livelihoods. Despite these constraints, the community perceives coffee agroforestry as a transformative strategy for resilience, sustainable land management, and inclusive local development in vulnerable rural regions.

Can carbon insetting deliver credible sustainability outcomes in forest-risk supply chains? A critical perspective from soy and cattle production in Argentina’s Gran Chaco

Comparing allometric models to machine learning models for aboveground biomass estimation in agroforestry systems in Kenya

Interactive effects of climate change and grazing history on soil microbial diversity in Mediterranean agroforestry systems

Uncovering seasonal "growth-nutrient-chemical components" coupling Alpinia galanga (L.) Willd.: A comparison between monoculture and intercropping agroforestry systems

Sandalwood (Santalum album L.) is an endemic species of ENT – Indonesia, currently listed as a vulnerable species on the IUCN Red List. The study seeks to understand the status of sandalwood among agroforestry farmers, on how the ecosystem balance of the sandalwood trade has been maintained for centuries under traditional management, and how current institutional arrangements or policies seem to be leading to unsustainable sandalwood production and trade. Primary data were collected through a survey of eight villages in the South Central Timor district, West Timor, purposively selected based on the distribution of the sandalwood ecosystem; secondary data and information were obtained from manuscripts and open-access sources. The research showed that the current sandalwood trees are mostly found in Mamar, a traditional agroforestry system, with dominant respondents (32%) maintaining populations of fewer than 15 trees, and only 2% respondents own more than 50 trees; however, accounted 80% respondents were willing to plant sandalwood. The paper highlighted that traditional sandalwood management practices during the early sandalwood trade contributed to the sustainable, environmentally sound nature of the sandalwood natural production system. Conversely, induced sandalwood management practices, in general, lead to overexploitation and social distrust, creating unsustainable sandalwood production. The paper suggested that sandalwood cultivation should focus on private land in Mamar, and that regulations and technical standards for sandalwood production and trade should be designed to increase participation and promote sustainable, environmentally friendly dryland management. Sandalwood trees should receive special consideration and be valued more in biodiversity and carbon credit schemes to attract more upland farmers to plant and conserve them.

Against the background of global climate change, soil salinization has emerged as a major abiotic stressor constraining agroforestry productivity worldwide. Root-recruited microbes enhance plant stress resilience, and host-microbe interactions depend on plant root metabolism. Stress-tolerant plant genotypes exhibit a marked capacity to enrich beneficial root-associated microbes through specialized metabolic responses, thereby facilitating phenotypic plasticity. However, the molecular mechanisms underlying these plant-microbe interactions remain unclear. In this study, we compared salt tolerance among three poplar varieties under aseptic and non-aseptic conditions, and analyzed their rhizosphere bacterial community responses to salt stress. We found that microbial inoculation modulated poplar salt tolerance, and poplar shaped rhizosphere bacterial communities in a genotype-dependent manner. Transcriptome sequencing and targeted metabolomic analysis indicated that salt-tolerant poplar plants preferentially activate the phenylpropanoid biosynthesis pathway, accompanied by the enhanced root secretion of benzoic acid (BA) and salicylic acid (SA) and up-regulation of CHD-18g encoding cinnamoyl-CoA hydratase/dehydrogenase. Overexpression of CHD-18g increased rhizosphere Pseudomonas abundance by enhancing BA and SA biosynthesis. Binary interaction assays further showed that the BA-induced Pseudomonas taxa mitigated salt stress and promoted poplar growth under salt stress. Our findings propose a framework linking host gene expression, root metabolism, and key microbial taxa in conferring salt tolerance. This work uncovers a metabolic signaling mechanism by which trees shape their root microbiome to enhance stress adaptation, offering actionable genetic and ecological strategies for improving tree resilience in sustainable agroforestry systems.

Forest structure and fragmentation dynamics in cacao-producing landscapes of Amazonas, Peru, revealed by multi-temporal land-use change and spaceborne LiDAR.