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Support of total maximum daily load programs using spatially referenced regression models

G. McMahon·R. B. Alexander·S. Qian
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Abstract

The spatially referenced regressions on watershed attributes modeling approach, as applied to predictions of total nitrogen flux in three North Carolina river basins, addresses several information needs identified by a National Research Council evaluation of the total maximum daily load program. The model provides reach-level predictions of the probability of exceeding water-quality criteria, and estimates of total nitrogen budgets. Model estimates of point- and diffuse-source contributions and nitrogen loss rates in streams and reservoirs compared moderately well with literature estimates. Maps of reach-level predictions of nutrient inputs and delivery provide an intuitive and spatially detailed summary of the origins and fate of nutrients within a basin.

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G. McMahon, R. B. Alexander, S. Qian. 2003. Support of total maximum daily load programs using spatially referenced regression models. https://doi.org/10.1061/(asce)0733-9496(2003)129%3A4(315)

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