Changing Soil Science to Understand Soil Change and Ecosystem Services.

Soils provide, and support, a range of provisioning, regulating and cultural ecosystem services. A major challenge is to identify and account for ‘soil change’ and the contribution or impact this has on ecosystem service delivery. One way to attempt this is by better accounting for resource use, ‘change’ in the resource, and how this change impacts other resources. Major international initiatives are seeking ways to quantify and account for change. For example the United Nations recognizes that Gross Domestic Product (GDP) indicators in the system of national accounts (SNA) are deficient in this regard. Basically, the costs of environmental degradation, natural resource depletion and non-market values are not included because the SNA only considers goods and services transacted in markets or accounted for as a benefit. Worse still, the degradation and loss of environmental resources often involves additional economic activity and thus increases GDP. Thus, the current macro-economic measures of performance that inform policy and debate can provide misleading information with respect to sustainable use of resources.

Limitations of the SNA in relation to the environment and depletion of natural resources have led to the development by the UN of the 2003 System of Environmental and Economic Accounts (SEEA). The approach articulated within the SEEA is not to explicitly include monetary estimates of environmental damage (such as soil erosion) and resource use in accounts. Instead the SEEA advocate disaggregated, issue specific “satellite” accounts that sit beside the existing SNA that capture resource use and environmental degradation. With regard to soils, SEEA has proposed initially capturing the change in area and volume of soil that can operate as a biological system under different land uses. Although area losses clearly represent degradation of the resource, the loss of soil thickness due to erosion is a rather crude degradation measure, not least because of preferential loss of biologically active soil components. The accounts currently make no attempt to assess soil condition or how this affects the supply of ecosystem services.

We present data from UK and European initiatives to develop monitoring and modelling frameworks that allow us to better understand the state and change of soils. For example, the Countryside Survey in the UK attempts to measure the state and change of the British countryside and has operated for 30 years; and a similar effort (GMEP) is now being undertaken in Wales to monitor the impact of agri-environmental schemes. Initiatives such as the EU SoilTrEC project are developing capacity to predict effects on water and solute fluxes of soil structural changes induced by climate and management. All these efforts seek to identify and quantify soil change on anthropogenic time scales and provide decision-makers with an understanding of how ecosystem service delivery will be affected.