Modelling Soil Organic Matter Dynamics – Global Challenges - Sustainable Management of Soil Organic Matter - page 42

organic matter (Antle, 1996). Management practices are to a large degree
driven by economic factors. Thus, the feedbacks and interactions between
biophysical and economic components that govern the larger human-
dominated ecosystem are fundamental to predicting potential changes in
soil C amounts and dynamics. This is particularly true for assessing the
potential outcome of greenhouse gas mitigation policies in which changes in
soil C and other soil-derived greenhouse gases will have a direct effect on
farm income. However, it is equally true for assessing the effects on soil C of
climate change or other changes in policies or economics to which farmers
respond. Understanding regional soil organic matter dynamics, as driven by
economically based management decisions, will require a whole-ecosystem
approach where the interactions between SOM, crop yields, economic
returns and subsequent changes in management feedback to determine
SOM and crop responses (Fig. 2.1). Integrating SOM models into such
systems will provide valuable tools to guide policy and decision-making on
many of the pressing environmental issues facing society.
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