Vegetation Restoration and Other Actions to Enhance Wildlife in European Agricultural Landscapes
José María Rey Benayas and James M. Bullock
Abstract Intensive farming practices are a major cause of destruction and degradation of natural vegetation throughout the world. However, in some regions including Europe, semi-natural vegetation and farmland systems harbour wildlife of conservation concern and other values. We propose widespread strategic revegetation—a type of restoration related to wildlife-friendly farming or land sharing with little competition for land—by planting woodland islets and hedgerows for ecological restoration in extensive agricultural landscapes. This approach allows wildlife enhancement, provision of a range of ecosystem services, maintenance of farmland production, and conservation of values linked to cultural landscapes. In contrast, vegetation restoration by land separation, namely secondary succession following farmland abandonment and tree planting, would provide all these benefits only at the landscape or regional scales as this restoration type is at the expense of fieldlevel agricultural production. Furthermore, seed dispersal from revegetated elements favours passive restoration of nearby abandoned farmland and, consequently, rewilding. Revegetation of riparian systems and other actions that do not compete for land use such as introduction of bird perches, refuges for wildlife or creation of ponds would provide similar benefits. Revegetation of roadsides and roundabouts may support dispersal and spread of species but may function as ecological traps for wildlife. We provide a practioner's perspective related to land-sharing restoration actions in central Spain. We conclude that practical restoration projects—particularly strategic revegetationare essential if we want to halt biodiversity loss and encourage the return of wildlife in agricultural landscapes.
Keywords Biodiversity • Farmland • Land separation • Land sharing • Seed dispersal •Strategic revegetation
A large part of environmental degradation is due to the expansion of the agricultural frontier in many parts of the world together with intensification of farming methods. For instance, Ellis and Ramankutty (2008) indicated that 14 of the World's 21 major biome types have agricultural use. Agricultural land covered 4.91 billion ha, ca. 38 % of the terrestrial surface, in 2011 (FAOSTAT 2013), to the detriment of natural vegetation cover. However, at the global scale, the amount of agricultural land has currently reached a plateau (Rey Benayas and Bullock 2012), with a redistribution of agricultural land from temperate areas towards the tropics (Foley et al. 2011; Rey Benayas and Bullock 2012). In the European Union (EU-27) 43 % of the land is under agriculture (FAOSTAT 2013), but this proportion is often nearly 100 % at more local scales such as the Castillian plains of Spain.
A powerful approach to countering the negative impacts of agricultural expansion and intensification is ecological restoration. Restoration actions are increasingly being implemented in response to the global biodiversity crisis, and are supported by agreements such as the global Convention for Biological Diversity—a major target of its strategic plan for 2020 is restoring at least 15 % of degraded ecosystems—and the EU Council's conclusions on biodiversity post-2010, e.g. “halting the loss of biodiversity and the degradation of ecosystem services in the EU by 2020, and restoring them in so far as feasible”. Such policy initiatives are useful, but raise questions about our ability to manage and restore ecosystems to supply multiple ecosystem services and biodiversity (Bullock et al. 2011). For instance, there is often a trade-off between agricultural production that meets societal needs for food and fiber vs. other services and conservation of biodiversity (Pilgrim et al. 2010).
Recent discussions about the future of farming have contrasted “land sharing”— sometimes called “wildlife-friendly farming”with “land separation”. The former advocates the enhancement of the farmed environment, while the latter, also called “land sparing”, advocates a separation of land designated for farming from that for conservation (Fischer et al. 2008; Phalan et al. 2011). Rey Benayas and Bullock (2012) argued that these approaches should not be seen as alternatives, but as representing the range of actions that can be best combined to enhance biodiversity and ecosystem services. Furthermore, considered broadly the land sharing/land separation approaches might be seen as a gradient rather than as a dichotomy as they represent actions at different spatial scales. However, when planning actions at specific locations, there is a true contrast between the land sharing and separation approaches (e.g. Phalan et al. 2011), as we will demonstrate. In this article we will first examine the complex role of agricultural systems in both delivering and harming wildlife (the so called “agriculture and conservation paradox”, Rey Benayas et al. 2008). Then we focus on approaches to enhance wildlife—including rewilding—and associated ecosystem services in agricultural landscapes. On one hand, we will examine restoration actions that do not or hardly compete for land use to produce systems in which agricultural production is in partnership rather than in conflict with the enhancement of wildlife. Among the various restoration actions, we will pay particular attention to strategic revegetation by planting woodland islets and hedgerows. We will present a practitioner's perspective of implementation of such restoration actions in central Spain.
Cropland has mostly spread at the expense of forest land in Europe (Foley et al. 2005). Thus, on the other hand, we will focus on forest regrowth or passive restoration following farmland abandonment and tree plantations on cropland as examples of habitat restoration by land separation. Strategically revegetated elements and forest regrowth are linked by species dispersal processes. Thus, ecological restoration in farmland may maintain agricultural practices, promote wildlife return, and accelerate rewilding sensu Navarro and Pereira (see Chap. 1) in circumstances where the socio-ecological dynamics promote abandonment.