The Konza Prairie Research Natural Area was established in 1970 using replicated watershed units to study the effects of fire frequency on tallgrass prairie. Seastedt and Benning propose to take advantage of this long-term fire frequency experiment with a retrospective analysis of indices of net primary production (NPP) using remote sensing and Geographic Information System procedures. They will test the hypotheses that 1) fire frequency has measurable effects on remotely sensed indices of foliage NPP, 2) that topoedaphic effects influence watershed patterns, and 3) that growing season precipitation mediates fire frequency effects. The results from this effort will be combined with small plot studies to modify the CENTURY model so that it accurately predicts fire effects on NPP and soil dynamics. This research addresses an important part of vegetation - atmosphere interactions and is related to the problem of detecting effects of global change on biotic processes. The institutional support for this research is outstanding.
