|Jordan, Nicholas - UNIVERSITY OF MINNESOTA|
Submitted to: Society for Range Management Meeting Proceedings
Publication Type: Proceedings
Publication Acceptance Date: December 31, 2003
Publication Date: January 28, 2004
Citation: BLUMENTHAL, D.M., JORDAN, N., RUSSELLE, M.P. SOIL CARBON ADDITION CONTROLS WEEDS DURING RESTORATION. CAN IT WORK IN ESTABLISHED PRAIRIE?. SOCIETY FOR RANGE MANAGEMENT MEETING PROCEEDINGS. 2004. Technical Abstract: Soil nitrogen enrichment, and consequent vigorous weed growth, is thought to hinder the restoration of tallgrass prairie. Adding carbon to the soil may facilitate prairie restoration by inducing immobilization of plant-available nitrogen. Early attempts to use this method, however, have had mixed results. We compared the productivity of 10 weeds and 10 tallgrass prairie species under 18 levels of C addition, ranging from 0 to 3,346 g C m-2. Carbon was tilled into the soil prior to planting. To control for non-N effects of C addition, N was added to a subset of plots. Relative to untreated plots, the highest level of C addition resulted in an 86% decrease in available NO3-N, a 15-fold increase in early-season light availability, a 54% decrease in weed biomass, and an 8-fold increase in prairie biomass. Nitrogen addition significantly reduced or reversed all of these effects. Significant species-specific responses to C addition included decreased biomass for five annual weeds and increased biomass for six prairie species, one annual weed, and three perennial weeds. These results suggest that C addition may be a useful tool for restoring N-limited plant communities. It is less clear, however, whether C addition can be used to control invaders of established plant communities. A new experiment asks this question, testing the interactive effects of C and water addition on the invasibility of mixed-grass prairie. Added weed species include cheatgrass and five perennial forb weeds.