Non-cropped fragments as important spider reservoirs in a Pampean agro-ecosystem

POMPOZZI, GABRIEL; MARRERO, HUGO J.; HAEDO, JOANA; FRITZ, LAURA; TORRETTA, JUAN P.

ANNALS OF APPLIED BIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2019 vol. 175 p. 326 - 335

0003-4746

Agricultural landscapes include patches of cropped and non-cropped habitats. Non-cropped fragments are often source habitats for natural pest predators which colonise less suitable agricultural fields. The goals of the present study were: (a) to evaluate the contribution of non-cropped fragments to agro-ecosystems as biodiversity reservoirs and ecosystem service providers, by assessing the abundance of spider species and their diversity and (b) to quantify the spatial variation in spider communities across different non-cropped fragments and crops. We hypothesised that non-cropped fragments function as spider diversity reservoirs with better conditions for reproduction than crops. We collected spiders from 10 restored fragments having had no disturbance for 20 years and four field edges, along a gradient inside the crop adjacent to each fragment. Overall, we collected 3,591 spiders belonging to 49 species/morphospecies in 14 families. Non-cropped fragments had a central role in the spider community, as estimated through species?habitat networks. We found differences in the diversity and abundance of spiders between non-cropped and cropped fragments. However, these differences were only for immature spiders, whose abundance decreased from non-cropped fragments towards the inside of crops. Our results highlight the importance of non-cropped fragments in agro-ecosystems as important source habitat patches, reservoirs of biodiversity and sites where spider reproductive success is possibly higher.