The Nitrogen Cascade, from the Nooksack to the Globe

Western undergrad Savanna Dayton and grad student Lauren Cohen sample stream flow and nutrient concentrations in Schell Creek, near Ferndale, to help calibrate models of riparian nutrient retention.

Archived video from this presentation.

Nitrogen (N) fertilizers have helped fuel the agricultural revolution and feed an exponentially growing human population since the 1950’s. However, any excess nitrogen – that which the crops don’t capture - can escape into the environment and cause a variety of environmental and human health problems, from local air and water pollution to global climate change. And managing nitrogen use is tricky: because N is transformed by a variety of biological and chemical processes in air, soil and water, reducing N release at one point in this “nitrogen cascade” may just cause greater release at other points. My lab is working on these issues at a variety of scales. Locally, grad students are working to model the impact of riparian buffers on nitrogen retention along the Nooksack River and its tributaries. That is, can planting trees and shrubs along creeks, primarily intended to help improve salmon habitat, also help prevent excess nutrients from causing eutrophication in Bellingham Bay? Regionally, we’re part of the Nooksack-Fraser Transboundary Nitrogen (NFTN) Project, a multi-agency, cross-border collaboration seeking to understand sources, sinks and impacts of nitrogen in the U.S. and Canadian parts of the Nooksack Watershed, Lower Fraser Valley, and Salish Sea. Globally, NFTN is part of the project “Towards an International Nitrogen Management System” (INMS), based at the University of Edinburgh, Scotland. We are one of seven global demonstration regions seeking to better understand N benefits, impacts, and management under a variety of social, cultural, and economic conditions. In this talk, I’ll describe the progress that we’re making and how these different scales of inquiry help inform one another.