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Abstract Non‐crop habitats are essential for sustaining biodiversity of beneficial arthropods in agricultural landscapes, which can increase ecosystem services provision and crop yield. However, their effects on specific crop systems are less clear, such as soybean in South America, where the responses of pests and natural enemies to landscape structure have only recently been studied.Here, we analysed how native forest fragments at local and landscape scales influenced arthropod communities, herbivory and yield in soybean fields in central Argentina. To do this, we selected soybean fields located in agricultural landscapes with varying proportions of forest cover. At two distances (10 and 100 m) from a focal forest fragment, we sampled natural enemy and herbivore arthropods, and measured soybean herbivory and yield. We focused on herbivore diversity, abundance of key soybean pests in the region (caterpillars and stink bugs), and their generalist and specialist natural enemies.Higher abundance of predators, lower herbivory rates and increased yield were found near forests, while overall forest cover in the landscape was positively related with parasitoid and stink bug abundance, soybean yield, and negatively with herbivory. Moreover, yield was positively linked to richness and abundance of generalist and specialist enemies and independent of herbivory according to piecewise Structural Equation Models.Synthesis and applications. Our results show positive effects of native forests on biodiversity and yield in soybean crops, highlighting the need for conservation of forest fragments in agricultural landscapes. Moreover, the relation between natural enemies and crop yield suggests that Chaco forests support a diverse and abundant community of natural enemies that can provide sustained levels of ecosystem services and result in positive effects for farmers.
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This content will become publicly available on January 1, 2027
Successional and native forests predict the occurrence and infection status of Chagas disease vectors in Panama
Abstract Changes in land use and land cover (LULC) due to agricultural expansion, commercial land management and other human‐driven modifications significantly influence the ecology of pathogens and vectors. This underscores the urgent need to understand how these respond to rapid and dynamic land use changes in these ecosystems and, critically, to identify strategies for mitigating their impacts.In tropical Central and South America, palm trees serve as primary habitats forRhodniuskissing bugs, vectors ofTrypanosoma cruzi, the etiologic agent of Chagas disease. This study investigates how LULC, weather and traits of the palmAttalea butyraceapredict the occurrence and infection ofRhodnius pallescens, integrating field data collection, molecular detection and spatial and hierarchical analyses across a rural landscape in Panama.Rhodnius pallescenswere collected from 46 palms in 11 communities with different landscape compositions including native forests, grasslands, successional forests and artificial structures. Robust occupancy modelling using land cover data at 10 m2resolution revealed that successional forest cover at 300 m spatial scale predicted greater occurrence ofR. pallescens, whereas native forest predicted lower occurrence. Quadratic models outperformed linear models, indicating occupancy peaks at intermediate land covers and palm tree traits.Real‐time PCR assays detectedTrypanosomainfections in 70% ofR. pallescensacross communities. Spatial autocorrelation analyses showed significant spatial clustering forT. cruzibut not forTrypanosoma rangeli. We used generalized additive mixed models to assess the influence of palm‐level and landscape‐scale attributes on parasite infection and identified significant nonlinear positive associations betweenT.cruziinfection and native forest and grassland, with high predictive accuracy (AUC = 0.90).Synthesis and applications. Findings here show that successional forest predicts greater kissing bug infestation risk in palm trees, whereas native forest predicts lower kissing bug occurrence but greater infection withT. cruzi. These insights can guide land use planning towards vegetation management practices that help minimizeT. cruzitransmission risks for rural communities. Importantly, vector surveillance should target forest‐grassland ecotones and consider forest successional stages near settlements, with intensified monitoring after disturbances; this approach is applicable to other vector‐borne pathogen systems shaped by land use change.
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- Award ID(s):
- 1924200
- PAR ID:
- 10659661
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Applied Ecology
- Volume:
- 63
- Issue:
- 1
- ISSN:
- 0021-8901
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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