Response of the shortgrass steppe plant community to fire

Authors: SCHEINTAUB, MADELINE - COLORADO STATE UNIVERSITY; Derner, Justin; KELLY, EUGENE - COLORADO STATE UNIVERSITY; KNAPP, ALAN - COLORADO STATE UNIVERSITY

Submitted to: Journal of Arid Environments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/26/2009
Publication Date: 9/11/2009
Citation: Scheintaub, M., Derner, J.D., Kelly, E.F., Knapp, A.K. 2009. Response of the shortgrass steppe plant community to fire. Journal of Arid Environments. 73:1136-1143.

Interpretive Summary: Responses of aboveground biomass production to fire in the shortgrass steppe rangeland ecosystem have been assumed to be strongly negative. Here we used a summary of previously published research findings and current experimental field findings to determine if responses are strongly negative for this plant community variable. Aboveground biomass production with prescribed fires in shortgrass steppe was slightly decreased or remained similar to non-burned areas, as apposed to the assumed strongly negative results. These results are in contrast to findings in rangeland ecosystems of the eastern Great Plains which are wetter and more productive, and where fire tends to promote aboveground biomass production through the removal of a large litter component.

Technical Abstract: Fire is an important driver of ecological pattern and process in grasslands worldwide, although its role in semi-arid systems is less well known. We utilized published studies and new experimental research to 1) provide a synthesis of existing knowledge of fire in the semi-arid grasslands of the North American Great Plains, and 2) assess the degree of similarity in semi-arid and mesic grassland responses to fire in this region. Based on published studies, burning has neutral to negative effects on aboveground productivity in semi-arid grasslands and variable effects on plant communities. To more rigorously assess fire effects, replicated experimental plots were established in ungrazed shortgrass steppe in northern Colorado and prescribed spring fire was applied in 2006 and 2007, 2006 only, or not at all. Aboveground net primary productivity decreased or remained unchanged with burning. Plant community changes included increases in perennial forbs, decreases in annual grasses and a positive response in annual forbs to the combination of fire and the wet conditions in 2007. Combined, these results indicate that post-fire changes in productivity in semi-arid grasslands are neutral to negative in contrast to positive responses in mesic grasslands, and not as strongly negative as previously assumed.