Advances in soil ecosystem services: concepts, models, and applications for earth system life support

The ecosystem services approach is gaining wide acceptance at the policy-making level as a framework for integrating science and policy regarding the natural environment. It is important that soil science clearly articulates how knowledge and understanding of the vadose zone soils can be transmitted through this framework into the decision-making process. Competition between food production, living space, and maintaining habitat for all of earth’s life-forms has never been so intense, so the need for soil security and vadose zone protection is paramount. Soil management can no longer be thought of in terms of single function management but instead needs to be considered and managed in the context of the multiple functions it offers. In this 10th anniversary issue of the journal, we assess progress in the development of a coherent soil ecosystem services framework using the natural resource management stock-flow and fund-service resource approach. We go on to examine some of the areas where the application of an ecosystems approach is gaining traction, which include national and local decision making as well as support for legal arguments in court

Soil functions in Earth's critical zone: key results and conclusions

This chapter summarizes the methods, results, and conclusions of a 5-year research project (SoilTrEC: Soil Transformations in European Catchments) on experimentation, process modeling, and computational simulation of soil functions and soil threats across a network of European, Chinese, and United States Critical Zone Observatories (CZOs). The study focused on the soil functions of biomass production, carbon storage, water storage and transmission, water filtration, transformation of nutrients, and maintaining habitat and genetic diversity. The principal results demonstrate that soil functions can be quantified as biophysical flows and transformations of material and energy. The functions can be simulated with mathematical models of soil processes within the soil profile and at the critical zone interfaces with vegetation and atmosphere, surface waters and the below-ground vadose zone and groundwater. A new dynamic model for soil structure development, together with data sets from the CZOs, demonstrate both seasonal fluctuations in soil structure dynamics related to vegetation dynamics and soil carbon inputs, and long-term trends (decadal) in soil carbon storage and soil structure development. Cross-site comparison for 20 soil profiles at seven field sites with variation in soil type, lithology, land cover, land use, and climate demonstrate that sites can be classified, using model parameter values for soil aggregation processes together with climatic conditions and soil physical properties, along a trajectory of soil structure development from incipient soil formation through productive land use to overly intensive land use with soil degradation. A new modeling code, the Integrated Critical Zone model, was applied with parameter sets developed from the CZO site data to simulate the biophysical flows and transformations that quantify multiple soil functions. Process simulations coupled the new model for soil structure dynamics with existing modeling approaches for soil carbon dynamics, nutrient transformations, vegetation dynamics, hydrological flow and transport, and geochemical equilibria and mineral weathering reactions. Successful calibration, testing, and application of the model with data sets from horticulture plot manipulation experiments demonstrate the potential to apply modeling and simulation to the scoping and design of new practices and policy options to enhance soil functions and reduce soil threats worldwide

On the value of soil resources in the context of natural capital and ecosystem service delivery

The ecosystem services approach endeavors to incorporate the economic value of ecosystems into decision making. This is because many natural resources are subject to market failure. As a result, many economic decisions omit the impact that natural resource use has on the earth’s resources and the life support system it provides. Hence, one of the objectives of the ecosystem services approach is to employ economic valuation of natural resources in micro- and macroeconomic policy design, implementation, and evaluation. In this article we examine valuation concepts, and ask why we might attempt to economically value the contribution of soils to the provision of ecosystem services. We go on to examine economic valuation methods and review economic valuation of soils. By surveying prices of soils on the web we are able to make a first, limited global assessment of direct market value of topsoil prices. We then consider other research efforts to value soil. Finally, we consider how the valuation of soil can meaningfully be used in the introduction of improved resource management mechanisms such as decision support tools on which valuation can be based, within the UN’s System of Environmental and Economic Accounts (SEEA) and policy mechanisms like Payments for Ecosystem Services (PES)