One of the research projects in the Hegarty Lab in the Department of Civil and Environmental Engineering at Case Western Reserve University focuses on reducing greenhouse gas emissions and pollutant runoff from wetlands.

Artificial wetlands exploit the critical ecological services provided by the plants and microbial communities of natural wetlands for the control of pollutants, the treatment of greywater, and more. Reducing runoff, particularly of nitrogen and phosphorus, is particularly important for reducing eutrophication and modulating algal blooms. Previous research has suggested that microbial communities in artificial wetlands are less diverse than in natural wetlands, but the impact that this has on contaminant removal or the production of greenhouse gasses is unknown. 

By pairing multi-omics (e.g. gene expression studies) with other molecular tools, we are identifying the key genes for metabolizing specific pollutants of local relevance to devise new systems for bioremediation and biodegradation. Critical to this work will be understanding the complex interactions between key microbial players (from archaea and bacteria to viruses and eukaryotes), as well as determining the ways in which environmental factors drive viral dynamics. 

Open questions motivating this work include:

• How do microbiomes vary between natural and engineered wetlands? 

• How are viruses affecting the fluxes of greenhouse gasses (GHG) or pollutant removal in engineered wetlands? 

• What design choices can improve pollutant removal or reduce GHG emissions in engineered wetlands?