A landscape level analysis of potential excess nitrogen in east-central North Carolina, USA

• Published in: Water, air, and soil pollution Vol. 146; no. 1-4; pp. 3 - 21
• Main Authors: GARTEN, C. T, ASHWOOD, T. L
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer 01.06.2003; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Applied sciences; BIOGEOCHEMISTRY; Biological and medical sciences; Biological and physicochemical phenomena; DENITRIFICATION; DEPOSITION; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Environmental monitoring; ENVIRONMENTAL SCIENCES; Exact sciences and technology; FERTILIZATION; Fundamental and applied biological sciences. Psychology; INVENTORIES; LAND USE; Literature reviews; MINERALIZATION; Natural water pollution; NITROGEN; NORTH CAROLINA; Pollution; Pollution, environment geology; Receiving waters; River basins; RIVERS; SEASONS; Soil and water pollution; Soil science; SOILS; USA; Water treatment and pollution; North Carolina; United States; North America; America; USA, North Carolina, Neuse R; USA, North Carolina; Cartography; Water resource management; landscape ecology; mass balance model; Nitrogen; Spatial variation; environmental health; Land use; Eutrophication; Seasonal variation; Risk assessment; Watershed; Bloom; Surface water; Water pollution; harmful algal blooms; Material balance; Ground water
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1023/A:1023923105942

The objective of this research was to arrive at an assessment of potential excess nitrogen (N) under different land cover categories in the Neuse River Basin (North Carolina, USA) on a seasonal basis. Data on five processes (atmospheric N deposition, fertilization, net soil N mineralization, plant uptake, and denitrification) that contribute to potential excess N under different land cover categories were obtained from a literature review. Factors were also estimated to apportion annual N fluxes among different seasons of the year. Potential excess N was calculated as the difference between inputs to and outputs from an inorganic N pool. If inputs exceeded outputs, then the difference was assumed to represent N at risk of loss from the landscape to surface receiving waters and groundwaters. Land covers that were classified as potential N sources were influenced by soil N inventories and rates of net soil N mineralization (which is a natural process). The results indicated that there are large land areas in the Neuse River Basin that could be classified as either a N source or a N sink. Such areas are potentially sensitive because future changes in land use, or small alterations in N fluxes, could convert areas that are essentially in balance with respect to N biogeochemistry into the N source or N sink category. In this respect, model predictions indicate that the timing of N inputs and outputs on the landscape can be a critical determinant of potential excess N.