Читать книгу Reconciling agricultural production with biodiversity conservation - Группа авторов - Страница 9

Introduction

More intensive, monocultural agriculture has been associated with a decline in diversity of habitat and plant species which leads to corresponding declines in diversity of insect, bird and mammal species. There is mounting evidence that a more biodiverse landscape improves ecosystem services which benefits farmers. This collection summarises the wealth of research on ways of improving biodiversity in agricultural landscapes, with a focus on temperate agriculture.

The first part of this volume reviews landscape approaches to biodiversity conservation, mapping and modelling biodiversity as well as assessing the economic value of biodiversity conservation practices. Part 2 reviews management practices promoting biodiversity such as field margins and hedgerows, ways of reconciling agricultural production and biodiversity in grassland management as well as the role of agroforestry in promoting biodiversity.

Part 1 Methods to study biodiversity in agroecosystems

The book begins with a focus on the challenge of mapping biodiversity in agricultural landscapes at the EU level. Chapter 1 reviews the current surveys of biodiversity in agricultural areas in the EU. It begins by examining established surveys, ongoing pilots and plans for new surveys at the EU level, focusing specifically on the monitoring of farmland birds and butterflies, grasslands, pollinators and soil biodiversity. The chapter also assesses where we stand in the short–medium term in terms of our knowledge of agrobiodiversity in the EU and which gaps still need to be filled to sufficiently describe biodiversity dynamics.

The next chapter looks at modelling biodiversity in agriculture. Models have been widely used in agricultural science to understand complexity, predict the consequence of change and extend knowledge to new scales. ‘Crop modelling’ began in the 1960s and is now well advanced and applied globally but is restricted to a few economic species. More recently, modelling has been expanded to cover biota as mediators of ecological process or as endpoints for assessment of environmental status. Chapter 2 examines the range of modelling approaches in biodiversity studies, including individual-based approaches that combine within- and between-species diversity, process-based models operating at plot, field and increasingly at landscape scales, integrated system models that seek optimal trade-offs between biodiversity and economic outputs, and global frameworks that combine the biophysical, economic, social and political forces acting on biodiversity. The chapter concludes with a more practical approach known as multi-attribute decision modelling that can be developed and applied by biodiversity managers and planners.

The subject of Chapter 3 is assessing the economic value of agricultural biodiversity. The chapter reviews developments in methods to assess the economic value of agricultural biodiversity, outlines their limitations and proposes a possible, novel way forward. It discusses the different definitions of agrobiodiversity. It then highlights ways of evaluating agrobiodiversity. This is followed by two sections, the first introducing and discussing the ecosystem services framework (ESF) and its limitations, the second outlining the integration of ecosystem interactions in the ESF. The chapter then explores two fundamental problems affecting the evaluation of agricultural biodiversity: the ecosystem services whose value cannot be derived from the market and uncertainty. On the basis of these considerations, the authors propose a novel way forward, the investor perspective, where by giving the natural environment the rights of a legal persona enshrined in a Bill of Rights, the authors address many of the drawbacks of current evaluation methods. The chapter concludes with recommendations for evaluators and decision and policy makers, and with an extended bibliography.

The final chapter of Part 1 examines functional biodiversity for the provision of agroecosystem services. In the context of sustainable agricultural development, the provision of other services beyond production is becoming a priority. Chapter 4 highlights that a functional approach to agrobiodiversity is the best approach to meeting this goal in both research and agricultural practice. The chapter includes an analysis of the development of studies on agriculture-biodiversity relationships and refers to two milestones that had a tremendous impact on research: the United Nation’s Convention on Biological Diversity (1992) and the Millennium Ecosystem Assessment (2005). Interest in the functional aspects of agrobiodiversity, i.e. the potential or actual provision of ecosystem services, has boomed in the latest 15 years, yet use of the term ‘functional biodiversity’ is still scarce. The chapter also provides a trait-based definition of functional biodiversity and a four-step methodology that should shed light on the potential of elements at each agrobiodiversity level – from gene to species and habitat – to provide single or multiple agroecosystem services in any context.

Part 2 Management practices to support agroecosystem services

Part 2 begins by discussing the role of field margins in biodiversity conservation in agroecosystems. Chapter 5 reviews research on ways of modifying the agricultural landscape to reverse the decline in a range of fauna and flora. The chapter starts by looking at the range of options for promoting biodiversity in agricultural landscapes. It then focuses on field margins, their characteristics and types as well as the role of field margins in agroecosystems. The chapter then reviews research on managing field margins to promote insect biodiversity. It also looks at managing field margins to promote rare arable plants (RAP), reptiles, amphibians, birds and mammals.

Chapter 6 considers the role of hedgerows in supporting biodiversity and other ecosystem services in intensively-managed agricultural landscapes. Over the past half century, agricultural intensification has substantially changed agricultural landscapes and farming systems. These changes have been beneficial to provisioning services, i.e. agricultural yields, but detrimental for biodiversity and associated ecosystem services. As a contribution to halting and reversing the decline, it has been suggested that conserving and/or restoring hedgerows would be beneficial. Hedgerows are key features of agricultural landscapes. The chapter begins by highlighting what hedgerows are and their role as a habitat in promoting biodiversity. It then looks at hedgerows and hedgerow networks and goes on to examine how hedgerows contribute to the provision of ecosystem services. The chapter also provides a case study on hedgerow plantation and bocage restoration and how it enhances biodiversity and other ecosystem services. It concludes by providing potential areas for future research as well as resources for further information.

The subject of Chapter 7 is reconciling production and biodiversity in management of pastures and grasslands. Grasslands are crucial for the conservation of biodiversity across the world. Current agricultural practices have increasingly replaced grasslands by crops or managed them more intensively, resulting in a dramatic reduction of biodiversity. Is it possible to reconcile profitable grassland production with conservation of biodiversity? The chapter reviews research on the relationship between biodiversity and the quantity and quality of biomass produced by grasslands. It also shows it is possible to manage grasslands to reconcile production and biodiversity of grasslands. A case study on flowering meadows is also provided, followed by an analysis of potential future trends in research.

The final chapter of the book focuses on the importance of agroforestry systems in supporting biodiversity conservation and agricultural production from a European perspective. Chapter 8 begins by reviewing the contribution of agroforestry to global biodiversity goals. It then discusses agroforestry and the protection of species and habitats, followed by a discussion of agroforestry and the maintenance and restoration of ecosystems. The chapter also analyses the importance of achieving sustainable agriculture and forestry practices as well as preserving global biodiversity.