Responses of the shortgrass steppe to fire

The structure and function of ecosystems result from interactions between key ecological drivers, the species present and the physical environment.  Similar systems may be shaped by similar drivers, but it is not always clear whether these systems respond to a particular driver in the same way or to the same extent.  If the systems do respond similarly, broader generalizations may be made encompassing both systems.  The goal of this study was to measure responses to fire in one grassland, the shortgrass steppe, and compare the observed responses to long-term data on the responses to fire in another grassland, the tallgrass prairie.  In the first growing season after a late spring burn, there were no major changes in overall productivity or diversity in the shortgrass steppe plant community.  This differed from the tallgrass prairie system where burning increases productivity and decreases diversity.  Perennial grasses were less productive in burned plots relative to control plots in this study, while in the tallgrass prairie burning increases growth of dominant perennial grasses.  Although tallgrass prairie and shortgrass steppe are both C4-grass dominated systems, they appear to be responding to fire in different ways. The broader goal of this study is to address the need for long-term, replicated experiments investigating the responses of the shortgrass steppe, not just to a single fire, but to a variety of fire frequencies.