Submitted to: Ecological Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 2000
Publication Date: August 6, 2000
Citation: PETERS, D.C., HERRICK, J.E. PLANT-SOIL FEEDBACKS AND RECRUITMENT CONSTRAINTS ON PERENNIAL GRASS RECOVERY FOLLOWING SHRUB INVASION. 85TH ANNUAL MEETING, ECOLOGICAL SOCIETY OF AMERICA. 2000. ABSTRACT P. 372. Technical Abstract: Recent climate change simulation analyses predict an expansion of Chihuahuan Desert grasslands and reduction in shrublands in the southwestern U.S. Our objective is to evaluate the importance of plant life history traits and soil development processes to responses of these ecosystems. We are using a spatially interactive gap dynamics model (ECOTONE) to predict vegetation responses for a variety of initial soil conditions, from well-structured soils with relatively high soil organic matter to highly degraded soils. Our model includes feedbacks between soil organic matter, water availability, plant recruitment, and growth. We are simulating sites located throughout the Chihuahuan Desert including the SEV-LTER and JER-LTER. We are also examining the importance of seed dispersal to the recovery of perennial grasses. Our results show that recovery at the landscape scale is highly heterogeneous and depends both on nthe initial vegetation and soil properties, as well as the modification of these properties through time due to plant-soil feedbacks. Recruitment is more important than plant growth in determining grass response. Recovery is also affected by climate interacting with vegetation and soil properties. Our plans include expanding the spatial component of the model to include the redistribution of water, soil, and nutrients across the landscape.