Title: | Modeling Phosphorus in the Lake Allatoona Watershed Using SWAT: I. Developing Phosphorus Parameter Values |
Authors: | Radcliffe, D.E., Z. Lin, L.M. Risse, J.J. Romeis, and C.R. Jackson |
Year: | 2007 |
Journal: | Journal of Environmental Quality |
Volume: | 38 |
Pages: | 111-120 |
Article ID: | |
DOI: | 10.2134/jeq2007.0110 |
URL (non-DOI journals): | |
Model: | SWAT |
Broad Application Category: | hydrologic & pollutant |
Primary Application Category: | data/component contribution to SWAT |
Secondary Application Category: | nutrient cycling/loss and transport |
Watershed Description: | Upper Etowah, Shoal Creek, Little/Noonday, Owl/Kellogg, Acworth/Allatoona, and Stamp/Rowland subwatersheds of the 2,870 km^2 Lake Allatoona watershed in northern Georgia |
Calibration Summary: | |
Validation Summary: | |
General Comments: | |
Abstract: | Lake Allatoona is a large reservoir north of Atlanta, GA, that
drains an area of about 2870 km^2 scheduled for a phosphorus
(P) total maximum daily load (TMDL). Th e Soil and Water
Assessment Tool (SWAT) model has been widely used for
watershed-scale modeling of P, but there is little guidance on
how to estimate P-related parameters, especially those related to
in-stream P processes. In this paper, methods are demonstrated
to individually estimate SWAT soil-related P parameters and to
collectively estimate P parameters related to stream processes.
Stream related parameters were obtained using the nutrient
uptake length concept. In a manner similar to experiments
conducted by stream ecologists, a small point source is simulated
in a headwater sub-basin of the SWAT models, then the instream
parameter values are adjusted collectively to get an uptake
length of P similar to the values measured in the streams in the
region. After adjusting the in-stream parameters, the P uptake
length estimated in the simulations ranged from 53 to 149
km compared to uptake lengths measured by ecologists in the
region of 11 to 85 km. Once the a priori P-related parameter set
was developed, the SWAT models of main tributaries to Lake
Allatoona were calibrated for daily transport. Models using
SWAT P parameters derived from the methods in this paper
outperformed models using default parameter values when
predicting total P (TP) concentrations in streams during storm
events and TP annual loads to Lake Allatoona. |
Language: | English |
Keywords: | |