Linear Landscape Elements and Heteropteran Assemblages within Mediterranean Vineyard Agroecosystems

Abstract

In agricultural systems, linear habitat features and resource shifting over the season can shape insect communities. When evaluating insect assemblages, the use of trait-based approaches allows measuring of the functional component of diversity which, combined with a taxonomical perspective, may help to understand how environmental factors drive community structuring. In Mediterranean vineyard agroecosystems, we assessed Heteroptera communities to evaluate linear habitat type (hedgerow vs. grass strip) and seasonality drive assemblages from both a taxonomical and a trait-based perspective. Morphometric traits related to dispersal ability or microhabitat and resource use were measured. Heteroptera community composition varied from hedgerows to strips and also changed over the season. However, the taxonomical response was not as strong as the trait one. Trait composition of the omnivorous heteropteran community remained stable when compared to those of phytophagous and predatory heteropterans, which were more sensitive to the evaluated factors. Given that each linear habitat type supports communities with different trait compositions, we highlight the importance of preserving a variety of habitats to achieve a high functional diversity. We also emphasize the need to develop studies at different spatial scales that allow to better understand the significance of landscape elements on shaping insect assemblages across different climatic regions.