DOI: 10.1016/j.watres.2018.04.004
Scopus记录号: 2-s2.0-85045216737
论文题名: Precipitation thresholds for fecal bacterial indicators in the Chesapeake Bay
作者: Leight A.K. ; Hood R.R.
刊名: Water Research
ISSN: 431354
出版年: 2018
卷: 139 起始页码: 252
结束页码: 262
语种: 英语
英文关键词: Fecal coliforms
; Indicator bacteria
; Shellfish closures
; Water quality prediction
Scopus关键词: Barium compounds
; Harvesting
; Monitoring
; Regression analysis
; Shellfish
; Water analysis
; Water quality
; Watersheds
; Bacterial indicators
; Environmental triggers
; Fecal coliforms
; Indicator bacteria
; Logistic regression analysis
; Poorly drained soils
; Precipitation threshold
; Water quality predictions
; Rain
; environmental marker
; rain
; surface water
; anthropogenic source
; bioindicator
; biomonitoring
; coastal zone
; environmental factor
; fecal coliform
; prediction
; threshold
; water quality
; watershed
; Article
; bay
; comparative study
; controlled study
; cropland
; environmental monitoring
; fecal coliform
; feces microflora
; geography
; Maryland
; nonhuman
; precipitation
; priority journal
; shellfish
; water analysis
; water quality
; watershed
; bay
; Enterobacteriaceae
; feces
; food contamination
; microbiology
; prevention and control
; Chesapeake Bay
; Maryland
; United States
; Bacteria (microorganisms)
; Bays
; Enterobacteriaceae
; Environmental Monitoring
; Feces
; Food Contamination
; Maryland
; Rain
; Shellfish
; Water Microbiology
英文摘要: Many coastal states of the United States restrict harvest of shellfish from select areas based on some environmental trigger. Such areas are classified as being conditionally approved. In Maryland, the trigger is an inch or more of rainfall that has fallen in the last 24 h. This study used 11 years of monitoring data to test the relationship between daily rainfall totals and densities of fecal indicators in Maryland shellfish harvest waters. Precipitation and fecal coliform (FC) water monitoring data from 2004 to 2014 were matched by date and watershed. The influence of antecedent rainfall conditions (i.e. rainfall in the preceding days or weeks) and the distance of each monitoring station to land were compared to the percent of samples exceeding the FDA criterion for managing shellfish harvest areas. Sample stations beyond 1000m from land had FC densities consistently below the FDA criterion and were excluded from further analysis. Rainfall events greater than an inch tended to result in significantly elevated FC for the following two days, followed by lower levels thereafter. The total amount of rain in the last three weeks was positively related to the proportion of samples with FC greater than the FDA criterion. Bay-wide, the percent of samples exceeding the FDA criterion rose from seven percent for rainfall less than an inch to 37% following one or more inches of rain. Watersheds were classified based on the percent of FC densities over the criterion when rainfall was an inch or more, with 41 of 81 watersheds showing FC responses indicative of potential conditionally approved areas, those shellfish growing areas where the one inch precipitation trigger may be applied. These areas largely overlapped the current conditionally approved areas defined by Maryland. The percent of open water, wetlands, and poorly drained soils explained a significant amount of the variability (R2 = 0.72) in the difference in percent of samples exceeding the FDA criterion when rainfall was greater than an inch and when it was less than an inch. Logistic regression analysis showed that the current trigger of one inch of rain in 24 h is predictive of FC densities over the FDA criterion, though the appropriate threshold will most likely depend on how far the particular shellfish growing area is from land and antecedent rain conditions. In watersheds with relatively high percentages of open water to total watershed size, higher rainfall thresholds might be appropriate. The approach taken in this study could be applied to individual stations and sub-watersheds, potentially allowing the reclassification of some shellfish harvest areas. © 2018 Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/112744
Appears in Collections: 气候减缓与适应
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作者单位: NOAA National Ocean Service, National Centers for Coastal Ocean Science, Cooperative Oxford Laboratory, 904 South Morris Street, Oxford, MD 21654, United States; University of Maryland Center for Environmental Science, Horn Point Laboratory, 2020 Horns Point Road, Cambridge, MD 21613, United States
Recommended Citation:
Leight A.K.,Hood R.R.. Precipitation thresholds for fecal bacterial indicators in the Chesapeake Bay[J]. Water Research,2018-01-01,139