Mixed biodiversity benefits of agri‐environment schemes in five European countries

TLDR

Agri‑environment schemes are an increasingly important tool for maintaining and restoring farmland biodiversity in Europe, yet their ecological effects remain poorly understood and their design is often driven by non‑ecological considerations that limit evaluation. The study aims to evaluate the biodiversity effects of agri‑environment schemes in five European countries using a robust approach, and to highlight that scheme objectives should distinguish between common species that respond to simple practice changes and endangered species that need more elaborate conservation measures. We compared species density of vascular plants, birds, bees, grasshoppers, crickets, and spiders on 202 paired fields, one with an agri‑environment scheme and the other conventionally managed. Across all five countries, agri‑environment schemes produced marginal to moderately positive effects on biodiversity, but uncommon and Red Data Book species benefited only in two countries and rarely at all.

Abstract

Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures.