Agriculture causes some of the largest impacts of land use and is a key influence on biodiversity conservation. Agriculture has both negative and positive impacts on biodiversity. The conversion of natural land and changes in agricultural land use directly result in habitat loss and fragmentation. Also, agriculture contributes to environmental impacts such as climate change, that indirectly cause biodiversity decline. In contrast, agriculture is a major contributor to Europe’s biodiversity, through diverse farming traditions that have resulted in a wide range of agricultural landscapes. In aggregate, however, farmland biodiversity shows a rapid decline, due to changes in management such as intensification and industrialisation of agriculture. For example, populations of farmland birds have more than halved in the last three decades.
To effectively conserve biodiversity, we need to define what is biodiversity, and what targets to set. This is not a straightforward task. Defining biodiversity and setting targets relies, to a large extent, on stakeholder input and societal values. One stakeholder may wish to conserve a specific group of vulnerable or iconic species – such as meadow birds, whereas another focuses on generic conservation measures to reduce extinction risk across species within agriculture. Others may argue that it is better to produce food as intensively as possible in a limited area, so as to spare other land from agriculture to conserve natural habitats, such as forest. Either way, creating or maintaining a suitable landscape for some species will potentially be less suitable for other species. Because it is not possible to boost all species everywhere while still delivering the provisioning services of food, fibre and increasingly energy, then one has to choose which landscapes and inhabiting species to conserve and to what extent.
The EU released the EU Biodiversity Strategy in 2011 to halt the loss of biodiversity by 2020 (European Commission, 2011). To ensure conservation of biodiversity in agriculture, the target is to maximise areas under agriculture covered by biodiversity related measures under the Common Agricultural Policy. However, biodiversity assessments at EU level have so far shown that biodiversity loss has continued, and that more stringent protection is required to stop biodiversity decline.
To develop more effective scenarios for biodiversity conservation on agricultural land, we interviewed experts and stakeholders in biodiversity conservation and assessed proposals for conservation in the Netherlands and France. More heterogeneous landscapes and more extensive (i.e. lower intensity) production were key in their priorities to boost biodiversity. Our scenario calculations suggested that measures to conserve a specific species or habitat, could be realized with a limited overall impact on the existing patterns of land use and food production, because measures only applied to a limited share of the land. Going to more extensive practices to mainstream biodiversity conservation throughout agriculture, however, would have a much larger impact on food production, because it would affect all agricultural production. Especially in case of a large reduction in food production, this could result in intensification of production or land use change elsewhere. Alternatively, a reduction in food production could be achieved by less food waste, less over consumption, and dietary changes.
In conclusion, there is an unavoidable trade-off between biodiversity conservation and food production. Therefore, conservation scenarios may have unwanted effects in regions other than the conservation area due to land use change elsewhere. More effective biodiversity conservation will depend on societal values and stakeholder input around land use. Targets are needed, but policy-makers should be aware of the process, values, frames, and narratives behind these targets.