"Environment" research area

Capturing and Repurposing Nitrogen and Phosphorus from Agricultural Runoff

Primary Investigator - Satoshi IshiiPrimary InvestigatorSatoshi Ishii
Industry PartnersNA
Award Type: Seed Grant - Undergraduate Research Scholar

Problem: Agricultural runoff sends nitrogen (N) and phosphorus (P) nutrients into rivers and lakes. This can cause eutrophication, where algae grow too quickly and damage the aquatic ecosystem. Agricultural runoff in Minnesota also contributes to the dead zone in the Gulf of Mexico. Some techniques can reduce runoff from fields, but it remains difficult to control N and P leaching completely.

Solution: The Ishii Lab will harness algae’s ability to grow quickly in the presence of excess N and P. Instead of causing eutrophication, the algae will remove N and P from runoff water in a bioreactor. Researchers will monitor water quality in the bioreactor and perform DNA/RNA analysis on efficient communities to optimize a granule-based algal bioreactor. Granules are microbial structures that sink when they become large enough, leaving clean water at the top. Bioreactors that use granular technology have higher nutrient removal efficiencies and less energy input compared to other nutrient removal systems. 

Impact: An algal bioreactor can improve water quality in Minnesota’s aquatic ecosystems, as well as the Gulf of Mexico, without sacrificing agricultural activity. The algae biomass can be harvested for energy or reused as fertilizer because of its high nutrient content.