An eddy covariance system for simultaneous flux measurements of total reactive nitrogen, ammonia, and nitrogen oxides (NOx).

SummaryNitrogen balance plays a critical role in agricultural food security and biodiversity. While some nitrogen addition, such as fertilization, is highly beneficial to agriculture, too much can result in lower crop yields and plant loss. Air pollution can tip the nitrogen balance toward unhealthy soil and poor growing conditions and affect a plant's ability to cope with drought. Understanding the role that different sources of air pollution play in the nitrogen budget will help inform decisions aimed at maintaining healthy, productive soil. Technologies are needed that can a) quantify the amount of nitrogen entering soil from the atmosphere, and b) determine the relative contributions of different pollution sources to the nitrogen budget at a farm or agricultural region.Aerodyne Research, Inc. is developing an air sampling system capable of measuring the amount of total "reactive" nitrogen entering the soil from air. It will also determine how much of this reactive nitrogen is from ammonia - a common agricultural pollutant - and how much is from NOx - a common urban pollutant. This system will combine advances in reactive nitrogen sampling (the "TRANC" reactor) and ammonia sampling (the "inertial inlet") with established measurement techniques to provide a unique insight into how air pollution affects agriculture and ecology. Aerodyne will build a field-ready system that will be demonstrated at a local farm and at an ecologically sensitive site. Use of this analytical tool will provide improved and more complete information for policy makers, influencing policy decisions to strengthen U.S. food security and maintain a healthy environment.