Trajectories Nutrient Dataset for Nitrogen (TREND-nitrogen)

In the present work, we have synthesized agricultural, population, and atmospheric deposition data across the contiguous U.S. for the period 1930-2017 to develop the Trajectories Nutrient Dataset for Nitrogen (TREND-nitrogen). The data is provided at U.S. county scale at an annual time step, and the following components of the N mass balance are included: atmospheric N deposition, N fertilizer, biological N fixation, manure N, crop N uptake, human N waste, and the overall N surplus. The dataset was constructed using information from a variety of sources, including the U.S. Census of Agriculture, the National Atmospheric Deposition Program, the United States Geological Survey, and the U.S. Census Bureau. Gap-filling and data-fusion techniques were utilized to provide annual-scale coverage and to harmonize data obtained from disparate sources over different time periods and varying spatial scales. The dataset will facilitate investigations of spatial and temporal changes in anthropogenic N dynamics at multiple scales across the U.S. in the context of historical changes in population, land use, and management.