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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 December 2, 2026
Arthropod rain in a lowland tropical forest
Abstract In lowland tropical forests, “arthropod rain” (i.e., arthropods falling from the canopy to the understory), represents a potentially important terrestrial nutrient flux.We investigated the composition, abundance, biomass and environmental drivers of arthropod rain on Barro Colorado Island, Panama. Pairs of traps (pan traps and pole traps) placed 1 m above the ground, respectively, collected fallen arthropods and arthropods potentially climbing to the canopy.Average (±SE) arthropod biomass in pan traps was dominated by Hymenoptera (primarily ants; 0.501 ± 0.023 mg dry mass m−2 day−1) and Lepidoptera larvae (0.228 ± 0.001 mg m−2 day−1). Total dry biomass in pan traps was 0.891 ± 0.033 mg m−2 day−1; thus, ca. 27 kg of arthropod biomass rains into the understory per km2per month during the wet season in this forest. This equates to ca. 3 million mid‐sized ants falling from the canopy per day on BCI as a whole.Arthropod abundance in pan traps, especially ants and spiders, increased marginally with the increasing number of high‐wind events. By contrast, arthropod biomass showed no relationship with wind or rain.Arthropod abundance was higher in pole traps than in pan traps and was dominated by Collembola and Acari. Compositional overlap between pan and pole trap contents suggests that some fallen arboreal arthropods regularly return to the canopy.These findings illustrate an understudied pathway linking canopy and understory food webs within tropical forests, and the complex interactions between environmental conditions and arthropod rain.
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- PAR ID:
- 10650968
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Insect Conservation and Diversity
- ISSN:
- 1752-458X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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