Microbes and Climate Change
Historical contingencies in how soil microbes respond to a change in the environment can make processes such as soil respiration less predictable from purely abiotic conditions. To understand how prior climate controls microbial community function under current conditions, we examine the drivers of historical contingencies using soils from across a steep precipitation gradient and experimental rainfall manipulations in central Texas.
Plants are home to a wide variety of fungi and bacteria living both inside plant tissues and on plant surfaces. We focus on two groups of fungi: fungal endophytes and arbuscular mycorrhizas. These microbes can dramatically affect plant growth and physiology, and we are particularly interested in how they improve plant stress tolerance. Using our extensive culture library of fungi, we explore the function of individual symbionts, study fungal interactions, and identify genomic and chemical mechanisms underlying plant-microbe interactions. Our ultimate goal is to develop a predictive trait framework for the outcome of symbiosis. In addition, the plant microbiome may prove to be a useful tool in agricultural management in the future.
To understand the high beta diversity in microbial communities, we work to distinguish local from regional controllers of community assembly. This work includes long-term studies of microbial communities across environmental gradients, microcosm experiments to test assembly processes, experimental manipulations of tree species in Neotropical rainforest, and studies in island ecosystems.
Microbial Roles in Ecosystem Function and Resilience
Soils and soil microbes are critical to how ecosystems function, but the complexity of soil microbial communities can limit our understanding of their contributions. This is particularly relevant for ecosystem restoration or engineering efforts. We have used large-scale experiments in Florida shrublands to examine the role of soil microbes in legacy effects and recovery of plant communities and biogeochemical cycling.