TY - JOUR
T1 - Impacts of environmental stressors on nonpoint source pollution in intensively managed hydrologic systems
AU - Botero-Acosta, A.
AU - Chu, M. L.
AU - Huang, C.
N1 - Funding Information:
Funding for this research was provided by the National Institute for Food and Agriculture (NIFA) project # ILLU-741-380. The authors would like to acknowledge the Danish Hydraulic Institute (DHI) for providing the educational licenses of MIKE-SHE and MIKE 11.
Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/12
Y1 - 2019/12
N2 - Agricultural practices intended to increase productivity can adversely affect our soil and water resources. Expected changes in climate and other social pressure are anticipated to exacerbate these impacts jeopardizing the sustainability of the agro-ecosystems. Watershed Management Practices (WMPs) are meant to achieve a rational use of resources as well as enhance ecosystem resilience to climate change. However, the effectiveness of WMPs depends on the complex interactions between processes occurring across the watershed. The objective of this study was to simulate the impacts of WMPs and projected climate on the sediment and nitrate-nitrogen (NO3-N) stream loads in an intensively managed watershed. The modeling framework was developed with the physically-based distributed model Mike SHE for the Upper Sangamon River Basin (USRB), an agricultural watershed in central Illinois. The fate and transport of sediment and NO3-N in the watershed and rivers was simulated using a generic advection-dispersion equation (ADE) with NO3-N and sediment as the main species. Results showed that non-structural WMPs, such as crop rotation and cover crops, presented the highest reductions of simulated NO3-N and sediment load, respectively, while structural WMPs had higher area-efficiency performance. On the other hand, climate conditions had a strong impact on the transport of both pollutants due to water fluxes alterations especially for a future dry climate scenario. Sediment transport was shown to be more sensitive to climate given that rainfall is one of the main drivers of the erosion processes. Outcomes from this research will give a more comprehensive approach toward understanding the impacts of environmental stressors at a watershed scale, and how they may be propagated to ecological systems.
AB - Agricultural practices intended to increase productivity can adversely affect our soil and water resources. Expected changes in climate and other social pressure are anticipated to exacerbate these impacts jeopardizing the sustainability of the agro-ecosystems. Watershed Management Practices (WMPs) are meant to achieve a rational use of resources as well as enhance ecosystem resilience to climate change. However, the effectiveness of WMPs depends on the complex interactions between processes occurring across the watershed. The objective of this study was to simulate the impacts of WMPs and projected climate on the sediment and nitrate-nitrogen (NO3-N) stream loads in an intensively managed watershed. The modeling framework was developed with the physically-based distributed model Mike SHE for the Upper Sangamon River Basin (USRB), an agricultural watershed in central Illinois. The fate and transport of sediment and NO3-N in the watershed and rivers was simulated using a generic advection-dispersion equation (ADE) with NO3-N and sediment as the main species. Results showed that non-structural WMPs, such as crop rotation and cover crops, presented the highest reductions of simulated NO3-N and sediment load, respectively, while structural WMPs had higher area-efficiency performance. On the other hand, climate conditions had a strong impact on the transport of both pollutants due to water fluxes alterations especially for a future dry climate scenario. Sediment transport was shown to be more sensitive to climate given that rainfall is one of the main drivers of the erosion processes. Outcomes from this research will give a more comprehensive approach toward understanding the impacts of environmental stressors at a watershed scale, and how they may be propagated to ecological systems.
KW - Advection-dispersion equation
KW - Hydrologic model
KW - MIKE 11
KW - MIKE-SHE
KW - MUSLE
KW - Nonpoint source pollution
KW - Transport model
KW - Water management practices
UR - http://www.scopus.com/inward/record.url?scp=85072583545&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85072583545&partnerID=8YFLogxK
U2 - 10.1016/j.jhydrol.2019.124056
DO - 10.1016/j.jhydrol.2019.124056
M3 - Article
AN - SCOPUS:85072583545
VL - 579
JO - Journal of Hydrology
JF - Journal of Hydrology
SN - 0022-1694
M1 - 124056
ER -