The Regionalization of National-Scale SPARROW Models for Stream Nutrients.

ABSTRACT: This analysis modifies the parsimonious specification of recently published total nitrogen (TN) and total phosphorus (TP) national-scale SPAtially Referenced Regressions On Watershed attributes models to allow each model coefficient to vary geographically among three major river basins of the conterminous United States. Regionalization of the national models reduces the standard errors in the prediction of TN and TP loads, expressed as a percentage of the predicted load, by about 6 and 7%. We develop and apply a method for combining national-scale and regional-scale information to estimate a hybrid model that imposes cross-region constraints that limit regional variation in model coefficients, effectively reducing the number of free model parameters as compared to a collection of independe

SUBMITTER: Schwarz GE 

PROVIDER: S-EPMC3307635 | biostudies-literature | 2011 Oct

REPOSITORIES: biostudies-literature