Abstract
Wetlands can improve water quality through natural processes including sedimentation, nutrient transformations, and microbial and plant uptake. Tailwater from irrigated pastures may contribute to nonpoint source water pollution in the form of sediments, nutrients, and pathogens that degrade downstream water quality. We examined benefits to water quality provided by a natural, flow-through wetland and a degraded, channelized wetland situated within the flood-irrigation agricultural landscape of the Sierra Nevada foothills of Northern California. The non-degraded, reference wetland significantly improved water quality by reducing loads of total suspended sediments, nitrate, and Escherichia coli on average by 77, 60, and 68%, respectively. Retention of total N, total P, and soluble reactive P (SRP) was between 35 and 42% of loads entering the reference wetland. Retention of pollutant loads by the channelized wetland was significantly lower than by the reference wetland for all pollutants except SRE A net export of sediment and nitrate was observed from the channelized wetland. Decreased irrigation inflow rates significantly improved retention efficiencies for nitrate, E. coli, and sediments in the reference wetland. We suggest that maintenance of these natural wedands and regulation of inflow rates can be important aspects of a best management plan to improve water quality as water runs off of irrigated pastures.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1837-1846 |
| Number of pages | 10 |
| Journal | Journal of Environmental Quality |
| Volume | 37 |
| Issue number | 5 |
| DOIs | |
| State | Published - Sep 2008 |
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ASJC Scopus subject areas
- Environmental Science(all)
- Environmental Chemistry
Cite this
Efficacy of natural wetlands to retain nutrient, sediment and microbial pollutants. / Knox, A. K.; Dahlgren, R. A.; Tate, K. W.; Atwill, Edward R.
In: Journal of Environmental Quality, Vol. 37, No. 5, 09.2008, p. 1837-1846.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Efficacy of natural wetlands to retain nutrient, sediment and microbial pollutants
AU - Knox, A. K.
AU - Dahlgren, R. A.
AU - Tate, K. W.
AU - Atwill, Edward R
PY - 2008/9
Y1 - 2008/9
N2 - Wetlands can improve water quality through natural processes including sedimentation, nutrient transformations, and microbial and plant uptake. Tailwater from irrigated pastures may contribute to nonpoint source water pollution in the form of sediments, nutrients, and pathogens that degrade downstream water quality. We examined benefits to water quality provided by a natural, flow-through wetland and a degraded, channelized wetland situated within the flood-irrigation agricultural landscape of the Sierra Nevada foothills of Northern California. The non-degraded, reference wetland significantly improved water quality by reducing loads of total suspended sediments, nitrate, and Escherichia coli on average by 77, 60, and 68%, respectively. Retention of total N, total P, and soluble reactive P (SRP) was between 35 and 42% of loads entering the reference wetland. Retention of pollutant loads by the channelized wetland was significantly lower than by the reference wetland for all pollutants except SRE A net export of sediment and nitrate was observed from the channelized wetland. Decreased irrigation inflow rates significantly improved retention efficiencies for nitrate, E. coli, and sediments in the reference wetland. We suggest that maintenance of these natural wedands and regulation of inflow rates can be important aspects of a best management plan to improve water quality as water runs off of irrigated pastures.
AB - Wetlands can improve water quality through natural processes including sedimentation, nutrient transformations, and microbial and plant uptake. Tailwater from irrigated pastures may contribute to nonpoint source water pollution in the form of sediments, nutrients, and pathogens that degrade downstream water quality. We examined benefits to water quality provided by a natural, flow-through wetland and a degraded, channelized wetland situated within the flood-irrigation agricultural landscape of the Sierra Nevada foothills of Northern California. The non-degraded, reference wetland significantly improved water quality by reducing loads of total suspended sediments, nitrate, and Escherichia coli on average by 77, 60, and 68%, respectively. Retention of total N, total P, and soluble reactive P (SRP) was between 35 and 42% of loads entering the reference wetland. Retention of pollutant loads by the channelized wetland was significantly lower than by the reference wetland for all pollutants except SRE A net export of sediment and nitrate was observed from the channelized wetland. Decreased irrigation inflow rates significantly improved retention efficiencies for nitrate, E. coli, and sediments in the reference wetland. We suggest that maintenance of these natural wedands and regulation of inflow rates can be important aspects of a best management plan to improve water quality as water runs off of irrigated pastures.
UR - http://www.scopus.com/inward/record.url?scp=51849140544&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=51849140544&partnerID=8YFLogxK
U2 - 10.2134/jeq2007.0067
DO - 10.2134/jeq2007.0067
M3 - Article
C2 - 18689745
AN - SCOPUS:51849140544
VL - 37
SP - 1837
EP - 1846
JO - Journal of Environmental Quality
JF - Journal of Environmental Quality
SN - 0047-2425
IS - 5
ER -