COLLABORATIVE RESEARCH: Dynamics of plant-soil feedbacks in changing environments

Western Illinois University, Macomb IL

Investigators

Abstract

Human activities have increased nitrogen (N) availability throughout the world. Nitrogen enrichment commonly results in increased plant productivity in terrestrial ecosystems. A large amount of work also indicates that anthropogenic nitrogen enrichment can lead to reduced plant species richness. Reductions in plant diversity have most commonly been attributed to plant resource competition, but other mechanisms may contribute to the observed loss of plant species in fertilized plots. The goal of this research is to include the 'unseen majority' - belowground microbial interactions - in understanding how N enrichment alters plant community structure aboveground. Plant interactions with microbes (e.g., soil parasites, symbionts, decomposers) could be an even more important determinant of plant diversity decline in response to N enrichment than simple plant resource competition. Utilizing microbial surveys of long-term fertilization plots, tissue culture experiments, and field manipulations in the moist meadow tundra and other grassland systems, previous hypotheses of diversity loss with N enrichment will be extended to include belowground microbial interactions. In addition, this research will promote the teaching, training and understanding of issues related to biodiversity and environmental change through virtual field trips accessible on the web, hands-on microbial activity sets distributed to high school classrooms, and the training of women, particular Hispanic women, scientists. Ultimately, the inclusion of belowground microbial interactions will improve predictive abilities regarding how environmental change factors such as N deposition may affect terrestrial biodiversity.