Using Soil Function to Characterize Highly Managed Lands.

We propose and demonstrate a new framework for characterizing land using soil function, as estimated by dynamic soil properties and processes that will help achieve conservation objectives for ecological sites under agronomic uses. Predicted outcomes include: (1) optimizing management based on land potential, (2) promoting development of innovative management systems, (3) supporting identification of high priority research needs, (4) improving efficiency of conservation planning, (5) increasing certainty of conservation outcomes, and (6) providing flexibility to promote innovative management systems. Within the framework, called the Land Management Optimization tool (LMO), reference conditions are defined for each agroecological site, which is a distinctive kind of land based on reoccurring soil, landform, geological, and climatic characteristics that differs from other kinds of land in its potential to support distinctive ranges of soil functions (as indicated by soil properties) and their responses to natural and human-caused disturbance. The framework will facilitate the collection, interpretation and application of information on current status (condition) of land relative to two reference conditions: (a) ecological potential, the maximum potential for a site with little or no human intervention (as reflected in the status of soil functions) and (b) attainable potential for an agricultural product group such as grains or forage, assuming current technology, market and regulatory conditions but differing management practices. Results using EPIC/APEX outcomes will be shown, including soil C sequestration and loss, N cycling and loss and other properties and processes affected by management. This approach directly fits current NRCS Soil Survey initiatives and relates to conservation program needs. Implementation of the framework will immediately increase usefulness of existing data by managers and provide a roadmap for long-term future data collection.