Land Suitability Evaluation Supported by GIS

Agricultural suitability mapping involves identifying land use patterns and assessing whether the current use is the most feasible both economically and environmentally. Essential to such activities is an accurate inventory of current land use. Asset mapping, like all other agricultural practices, is scale dependent, so various strategies for different study scales should be employed. A factor, however, that does not change with scale, whether it is at the subfield or national level, is that improved knowledge of what exists allows for better management practices.

Useful suitability assessments cannot solely be based upon biophysical resource information. Other factors include transportation networks, scale dependent localized economies, and social factors such as education and demographics. Obviously, large volumes of spatially related information need to be efficiently managed. The GIS required to service such research must incorporate high functionality and an ability to work seamlessly with both raster and vector data structures. Tabular information from census and agricultural statistics, raster image data, and vectorized productivity field data all add elements to the overall study. Such data integration, however, is only half of the story, and equal efforts need be applied in mapping and understanding relationships evident in the compiled information. Crop modeling, including soil/water requirement and geostatistical analysis, is critical at this stage to identify and make sense of complicated spatial relationships and, ultimately, substantiate trends and theories.

Looking at this abbreviated description of the processes involved in agricultural suitability mapping, it would be easy to become distracted from the ultimate aim, that of providing decision makers, whether farmers or politicians, with improved tools to aid land management and policy making processes.