The significance of woody vegetation's nonproductive elements for the overwintering of key biocontrol agents in intensively used agricultural areas

Abstract

Background: Successful overwintering habitats are critical for the long-term survival of biocontrol agents in agricultural landscapes, promoting ecosystem services by preserving beneficial arthropods. Although it is known that predatory arthropods overwinter in leaf litter in fruit orchards, the potential of nonproduction woody vegetation in agricultural landscapes for supporting overwintering spiders is poorly understood. Results: We compared spider assemblages overwintering in leaf litter of solitary trees, woody vegetation in line, and areal formations across three types of intensively used agricultural landscapes. We recorded 2502 overwintering spiders from 83 species and 20 families, with Linyphiidae being the most abundant. Assemblage composition and abundance were significantly influenced by landscape type, woody vegetation structure, adjacent land use, vegetation identity and litter weight. Linear and areal formations supported more spiders than solitary trees. Grass and leaf litter cover, as well as litter weight, affected both abundance and community composition. No significant differences were found in guild or ballooning traits across landscapes. Spider assemblages also differed between early and late winter, with higher abundance observed at the end of the season. Conclusion: Our study highlights that nonproduction elements of woody vegetation are important for the overwintering of spiders in agricultural landscapes. These findings are significant for landscape planning aimed at supporting ecosystem services and biodiversity conservation through the strategic integration of noncrop habitats.