Document Type
Article
Publication Title
Ecological Applications
Publisher
Ecological Society of America
Publication Date
2003
Volume
13
Issue
2
Disciplines
Ecology and Evolutionary Biology
Abstract
Tropical rain forest ecosystems are currently undergoing unprecedented rates of land conversion and land use change. Recent research suggests these activities profoundly influence nutrient cycling, but the principal mechanisms driving variation in nutrient status following land conversion are still not well understood. In this study, we used soils of varying fertility (oxisols and mollisols) in Costa Rica to investigate how conversion of tropical rain forest to cattle pasture affects the size and function of the microbial community, and to explore possible relationships between microbial dynamics and biogeochemistry.
Our pasture sites are relatively lightly managed, and total pools of carbon (C), nitrogen (N), and phosphorus (P) were not significantly different from their forest counterparts. However, pools of available elements were different; most notably, plant available forms of P were significantly lower in the oxisol pasture than in the oxisol forest site. In addition, we found that land conversion led to fundamental changes in the size and activity of the soil microbial community. Microbial biomass was consistently higher in forests than in pastures, particularly in the oxisol sites, where it was more than twice the pasture value. Forest sites were also characterized by a microbial community that was more active, responded more rapidly to carbon substrate additions, and showed strong seasonal variation. Our results provide evidence that changes in biogeochemical cycling following land conversion observed here and elsewhere may be directly related to changes in microbial community structure and function.
DOI
10.1890/1051-0761(2003)013[0314:SMDABI]2.0.CO;2
Recommended Citation
Cleveland, Cory C.; Townsend, Alan R.; Schmidt, Steven K.; and Constance, Briana C., "Soil Microbial Dynamics and Biogeochemistry in Tropical Forests and Pastures, Southwestern Costa Rica" (2003). Ecosystem and Conservation Sciences Faculty Publications. 17.
https://scholarworks.umt.edu/decs_pubs/17
Comments
Copyright 2003 by the Ecological Society of America. Cory C. Cleveland, Alan R. Townsend, Steven K. Schmidt, and Briana C. Constance 2003. SOIL MICROBIAL DYNAMICS AND BIOGEOCHEMISTRY IN TROPICAL FORESTS AND PASTURES, SOUTHWESTERN COSTA RICA. Ecological Applications 13:314–326.