| Title: | The relationship between land use and vulnerability to nitrogen and phosphorus pollution in an urban watershed |
| Authors: | Tasdighi, A., M. Arabi and D.L. Osmond |
| Year: | 2017 |
| Journal: | Journal of Environmental Quality |
| Volume (Issue): | 46(1) |
| Pages: | 113-122 |
| Article ID: | |
| DOI: | 10.2134/jeq2016.06.0239 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | hydrologic assessment |
| Secondary Application Category: | none |
| Watershed Description: | 4,367 km^2 Jordan Lake drainage area, located in north central North Carolina. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | SWAT served a relatively minor role in this study, being used to estimate streamflow at monitoring stations where measured streamflow data were not available. |
| Abstract: | Characterization of the vulnerability of water bodies to pollution
from natural and anthropogenic sources requires understanding
the relationship between land use and water quality. This study
aims (i) to explore the influence of upstream land use on annual
stream water concentrations and loads of total nitrogen (TN) and
phosphorus (TP) and (ii) to characterize the vulnerability of water
bodies to TN and TP pollution as a function of land use under
varying climatic conditions. Multiple linear regression models
were used across 23 stream locations within the Jordan Lake
watershed in North Carolina between 1992 and 2012 to explore
land use–water quality relationships. The percentage of urban
land use and wastewater treatment plant capacity were the most
important factors with strong (R2 > 0.7) and significant (p < 0.01)
positive correlations with annual TN and TP concentrations and
loads. Percent agricultural land was negatively correlated with TN
in 18 out of 21 yr of the study period. Using analysis of covariance,
significant (p < 0.01) differences were determined between
models developed for urban land use with TN and TP loads
based on annual precipitation. Using concentrations instead of
loads resulted in a nonsignificant difference between models for
average and wet years. Finally, a procedure was developed to
characterize the vulnerability to TN and TP pollution, computed as
the probability of exceeding the nutrient standard limits. Results
indicated that the vulnerability to TN and TP was controlled
primarily by urban land use, with higher values in dry years than
normal and wet years. |
| Language: | English |
| Keywords: | |