Title: | Comparing an annual and a daily time-step model for predicting field-scale phosphorus loss |
Authors: | Bolster, C.H., A. Forsberg, A. Mittelstet, D.E. Radcliffe, D. Storm, J. Ramirez-Avila, A.N. Sharpley and D. Osmond |
Year: | 2017 |
Journal: | Journal of Environmental Quality |
Volume (Issue): | 46(6) |
Pages: | 1314-1322 |
Article ID: | |
DOI: | 10.2134/jeq2016.04.0159 |
URL (non-DOI journals): | |
Model: | SWAT |
Broad Application Category: | pollutant only |
Primary Application Category: | phosphorus cycling/loss and transport |
Secondary Application Category: | model and/or data comparison |
Watershed Description: | 11 research sites located in the Southern U.S. |
Calibration Summary: | |
Validation Summary: | |
General Comments: | This study describes a comparison between the Texas Best Management Practice Evaluation Tool (TBET) and the APLE model. The authors state that TBET is a daily time step model but it is really an interface based on output from underlying SWAT simulations, and thus SWAT is identified as the model for this study. |
Abstract: | A wide range of mathematical models are available for predicting
phosphorus (P) losses from agricultural fields, ranging from
simple, empirically based annual time-step models to more
complex, process-based daily time-step models. In this study, we
compare field-scale P-loss predictions between the Annual P Loss
Estimator (APLE), an empirically based annual time-step model,
and the Texas Best Management Practice Evaluation Tool (TBET),
a process-based daily time-step model based on the Soil and
Water Assessment Tool. We first compared predictions of fieldscale
P loss from both models using field and land management
data collected from 11 research sites throughout the southern
United States. We then compared predictions of P loss from both
models with measured P-loss data from these sites. We observed
a strong and statistically significant (p < 0.001) correlation in both
dissolved (r = 0.92) and particulate (r = 0.87) P loss between the
two models; however, APLE predicted, on average, 44% greater
dissolved P loss, whereas TBET predicted, on average, 105%
greater particulate P loss for the conditions simulated in our
study. When we compared model predictions with measured
P-loss data, neither model consistently outperformed the other,
indicating that more complex models do not necessarily produce
better predictions of field-scale P loss. Our results also highlight
limitations with both models and the need for continued efforts
to improve their accuracy. |
Language: | English |
Keywords: | |