By Ann Briggs
A University of Nebraska–Lincoln research team has received a three-year, $496,722 National Science Foundation grant to investigate an understudied reservoir of organic nitrogen that may shape groundwater quality long after nitrogen management strategies are in place. A separate five-year, $357,000-plus award from the Nebraska Corn Board will help the researchers evaluate approaches that may proactively reduce nitrate risk before it reaches groundwater.
Clean groundwater is vital to drinking water supplies, agriculture and rural communities, but nitrogen contamination remains a persistent challenge. About four out of five Nebraskans drink groundwater. Much of it sits beneath some of the most productive agricultural land in the world. Nitrogen fertilizer is a critical crop nutrient; however, when it leaves the root zone, it becomes a loss to the farmer and a concern for drinking water.
The puzzling part is what happens when nitrogen management practices are improved. Nitrate levels in some Nebraska wells continue to rise, even years after modern nutrient strategies to reduce excess nitrogen use have been implemented. A research team based at the Nebraska Water Center thinks the explanation lies in historical nitrogen stores buried in the deep vadose zone between the surface and the water table. The two new awards will support collaborative efforts to better understand these underground processes and evaluate proactive solutions.
Nebraska Water Center researchers have studied the vadose zone for four decades to understand how nutrients, including nitrogen, move from the land surface to the groundwater. The vadose zone is a critical region for the storage, transport and transformation of chemicals that can affect groundwater quality.
Source : unl.edu