Quantifying and mapping ecosystem services

Since the publication of the Millennium Ecosystem Assessment’s outcomes in 2005 (Millennium Ecosystem Assessment 2005), there has been rapid growth in the science and policy of valuing ecosystem services and biodiversity for natural resource management decision making. Most prominent at the global scale is The Economics of Ecosystems and Biodiversity (2010), and at the national scale is the United Kingdom National Ecosystem Assessment (Bateman et al. 2011). New initiatives, such as the World Bank’s Global Partnership for Wealth Accounting and Valuation of Ecosystem Services1 and the Global Environment Facility (GEF)-funded Project for Ecosystem Services2 aim to get ecosystem service values into mainstream national accounting. Other recent global developments such as the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services3 and the Convention on Biological Diversity’s Strategic Plan for Biodiversity 2011–20204 aim to recognise, protect and enhance the values provided to society by biodiversity and ecosystem services. The biodiversity strategy of the European Union (EU) to 20205 demands improving the knowledge of ecosystem services and commissions its member states to map and assess the state of ecosystems and their services in their national territories by 2014. The integration of ecosystem service values into accounting and reporting systems at EU and national levels is expected be completed by 2020. All such efforts to better value ecosystem services demand robust quantification and mapping methods. Furthermore, the commodification of ecosystem service production, such as payments for ecosystem services, biodiversity and wetland banking, carbon offsets and trading and conservation auctions, depends on robust measurement of the stocks and flow of services to provide surety to participants in these markets. At a broader level of sustainability policy, there needs to be better understanding of where and what services are provided by a given piece of land, landscape, region, state, continent and globally, so that the level of provision of services can be monitored and managed. There also needs to be better understanding of conditions and threats to the natural capital that supplies ecosystem services so that finite resources can be targeted to where the enhancement of services is needed most. Maps are a very powerful tool to process complex data and information from ecosystem service quantification on different spatial and temporal scales and thereby support resource and environmental management as well as landscape planning. This special issue on ‘Quantifying and mapping ecosystem services’ contains a collection of papers that present the state of the art in ecosystem service quantification and mapping methodologies. The collection of papers in this special issue covers a broad spectrum of ecosystem service quantification and mapping, from the theoretical (Bastian et al. 2012) and review (Martinez-Harms and Balvanera 2012) style, to those of a more applied nature (Ericksen et al. 2012; Klug et al. 2012). Several papers focus on the single ecosystem service of water quality (Bastian et al. 2012; Klug et al. 2012; La Notte et al. 2012; Lautenbach et al. 2012) or habitat (La Notte 2012; Rolf et al. 2012), while other papers focus on the supply of multiple (or bundles of) ecosystem services (Ericksen et al. 2012; Guerry et al. 2012; Petz and van Oudenhoven 2012; Schulp et al. 2012; Vihervaara et al. 2012). The major characteristics of the papers that appear in this special issue are summarised in Table 1. The scale, resolution, input data sources and case study locations presented in these special issue papers are many and varied, from the local to the global and the fine-grained to the coarse-grained (Table 1). However, of most interest to readers are the major findings of the papers in this collection and how they contribute to the state of the art for quantifying and mapping ecosystem services. For example, using biophysical models (La Notte et al. 2012) or detailed species (Rolf et al. 2012) or biodiversity data (Vihervaara et al. 2012) to supplement land-cover/landuse data-based assessments will more accurately quantify ecosystem services than if using land-cover/land-use data alone. The selection of relevant ecosystem services and respective indicators is also important and careful selection will arguably result in more relevant and accurate maps for valuation (La Notte 2012) and decision making (Petz and van Oudenhoven 2012). A number of papers offer some insights into cases where lack of data makes quantifying and mapping ecosystem services more difficult. For example, Lautenbach et al. (2012) suggest a hierarchical approach across multiple scales could be used where high-resolution data are fragmented, while Ericksen et al. (2012) demonstrate that simple and relatively coarse land-use data are still very useful for mapping bundles of ecosystem services to aid decision making in developing countries that are traditionally data poor. Furthermore, Klug et al. (2012) demonstrate the potential of open source methods for collecting data and modelling ecosystem services that are complex in space and time.