Understanding how environmental factors affect soil C cycling processes is important, as soil is the largest C pool in terrestrial ecosystems, and any change in its size may feed back to the atmospheric CO2 concentration and ongoing climate change. It is therefore essential to improve our ability to predict the response of soil microbial processes to a changing environment. We submit that an increased knowledge of the fundamental biochemistry of microbial processes in intact soil communities will be central in this effort.
We have recently proposed a new method, called "metabolic tracer probing", which, in combination with a metabolic model, is used to quantify the C flow through the pathways of the central C metabolic network. Current models produce reasonable outcomes for aerobic soil, but need improvement to be more representative of the complexities of the soil microbial community and substrate dynamics, especially in anaerobic environments. Our objective is to apply community proteomics, metabolomics, transcriptomics, fluorescent microscopy and nano-SIMS in combination with metabolic tracer probing to generate the next generation of soil metabolic models. These technologies require a world-class instrumentation and expertise present at the Environmental Molecular Science Laboratory.
We have chosen two ecosystems in a Florida landscape to conduct our research: long-leaf pine woodland and sawgrass peatlands. These ecosystems have strong contrasts in relative C and N availability and oxygen concentration, two factors that have large effects on soil ecology and C cycling.