Nonpoint sources of nutrient pollution remain the most intractable drivers of water quality impairments in the United States.  Our research group explores biogeochemical nutrient removal processes in the context of the hydrological variability that is inherent to bioengineered “green” water infrastructure systems. Two key applications are constructed wetlands and edge-of-field biofiltration systems for agricultural applications (e.g., woodchip bioreactors).  A specific objective is advancing methods to enhance microbial nitrogen removal without stimulating production of the greenhouse gas nitrous oxide (N2O).  A new initiative in this research theme is the implementation of sensing and automated process controls in decentralized green infrastructure systems.  This allows water residence times and redox conditions in treatment systems to be deliberately controlled in order to optimize nutrient removal processes.

This research emphasizes a biogeochemical systems perspective, and explores complex interactions and couplings among the cycles of nitrogen, carbon, and  redox-sensitive metals; and between (geo)chemical, microbiological, and hydrological processes.  This work integrates analysis of chemical parameters with metagenomic and metatranscriptomic sequencing and bioinformatic analysis.  This work is funded by NSF and the New York State Water Resources Institute, and sequencing is supported by the community science program of the Joint Genome Institute.