ECOLOGICALLY-BASED SOIL MANAGEMENT FOR SUSTAINABLE AGRICULTURE AND RESOURCE CONSERVATION
Title: Soil Quality Assessment: Past, Present, and Future
Submitted to: Electronic Publication
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 15, 2008
Publication Date: December 29, 2008
Citation: Karlen, D.L., Andrews, S.S., Zobeck, T.M., Wienhold, B.J. 2008. Soil Quality Assessment: Past, Present, and Future. Electronic Journal of Integrative Biosciences. 6(1):3-14. Available: www.clt.astate.edu/electronicjournal.
Interpretive Summary: Soil is formed at a very slow rate, so it is critical to only use management practices that protect and preserve this precious resource. Traditionally, soil loss tolerance or "T" values have been used to evaluate the effects of soil loss on plant productivity. However, soil quality assessment encompasses much more than quantifying soil erosion. It includes assessments of physical, chemical, and biological properties and processes occurring within a specific body of soil. This study shows how the Soil Management Assessment Framework (SMAF) can be used to complement the Soil Conditioning Index (SCI) as a tool for evaluating the long-term effects of various soil management practices for the Conservation Effects Assessment Program (CEAP), the Renewable Energy Assessment Project (REAP), or programs such as the Conservation Security Program (CSP) or the Environmental Quality Incentive Program (EQIP). Soil quality assessment can help land owners and managers appreciate the multiple functions that soils perform and thus improve the resource management decisions they make.
Soil quality assessment can help land owners and managers appreciate the multiple functions that soils perform and thus improve the resource management decisions they make. Our objective is to show how the Soil Management Assessment Framework (SMAF) can complement the Soil Conditioning Index (SCI) and improve soil management. The SCI predicts whether a soil and crop management system will result in decreasing, stable, or increasing levels of soil organic matter (SOM). It is a good first step toward moving beyond T for conservation planning, but focusing on a single indicator (SOM) has raised concern among several groups including both scientists and producers. The SMAF offers a more comprehensive soil quality assessment by including biological, chemical, and physical indicators. One current limitation to using the SMAF for conservation planning is the requirement for measured data, but it is being adapted to interpret results of simulation models such as the Economic and Productivity Impact Calculator (EPIC). Opportunities for collaboration and further improvement of the SMAF are discussed, so it can ultimately be used to help guide management or restoration and contribute to long-term sustainability of soil resources.