Delineating regional and local Uniform Management Zones of agroecosystems using geospatial data

An agroecosystem can be viewed as being composed of a series of subsystems defined at different spatial scales. Delineation of a hierarchical structure of agroecosystems provides a framework for integrating biophysical, ecological and socioeconomic modeling, thus enhancing the study of the interacting effects in support of sustainable development and land management. In this study, a Uniform Management Zone (UMZ) hierarchy was proposed to reveal the hierarchical organization of agroecosystems. The hierarchy consists of seven levels of spatial units at different scales. Ranging from the smallest units to the largest, the levels are: site-specific management units, field management units, local UMZs, regional UMZs, country, continent and globe. The objective of this study was to develop a method of defining and delineating local and regional UMZs. A typical region in the Canadian Prairies was selected as the study area. A Majority-Combination method was developed to divide the study area into Regional UMZs using a land use map and circular moving windows. Annual crops were grouped into 4 types based on agronomic practices; cereals, oilseeds, pulses and fallow, A Ratio-Cell method was introduced to divide Annual Regional UMZs (RUMZ) into Local UMZs (LUMZ) based on crop group ratios and soil characteristics. MODIS NDVI was used to describe and evaluate the spatial characteristics of LUMZs. The RUMZ and LUMZ zones provide a spatial framework that identifies distinct combinations of land management practices and environmental conditions, thus supporting modeling at different spatial scales and providing a means of bridging the gap between the site-specific concepts of precision agriculture and the agroenvironmental and socioeconomic approaches used in broad policy and program development.