Ecological performance underlying ecosystem multifunctionality is promoted by organic farming and hedgerows at the local scale but not at the landscape scale.
Abstract
The relative contributions of agricultural intensity and semi-natural habitats to the multifunctionality and sustainability of ecosystems at different spatial scales remain largely under-investigated. In this study, we assessed the multifunctionality of 40 winter cereal fields and 40 hedgerows based on ecological, agronomic and socio-economic performance using data from field surveys and interviews with farmers. We specifically focused on the effects of local farming systems (organic vs. conventional) and management (cereals intercropped with legumes vs. monocrops), the effects of landscape heterogeneity related to hedgerow density, and the spatial extent of semi-natural habitat and organic farming. Multifunctionality indices associated with increased values of proxies for biodiversity conservation and pest control functions were higher for hedgerows than crop fields. Agroecosystem multifunctionality was similar between organic and conventional farming as a consequence of antagonistic responses of individual function proxies. While organic farming promoted the ecological performance of crops, conventional farming resulted in higher agronomic performance (i.e. yield). Interestingly, lower yields of organic crops were not systematically associated with reductions in socio-economic performance in terms of farmer income and labour. At the landscape scale, hedgerow density and the extent of semi-natural habitats and organic farming had little influence on agroecosystem multifunctionality or individual function proxies. Synthesis and applications. Our results confirm the high value of hedgerows and organic farming at the local scale for the ecological performance of ecosystems. Our study suggests that, among existing agri-environment schemes in Europe, hedgerow planting and organic farming are appropriate tools to optimise the ecological performance of ecosystems at the local scale even if antagonistic effects with agronomic performance should not be neglected.