Evaluation of potential factors affecting deriving conductivity benchmark by utilizing weighting methods in Hun-Tai River Basin, Northeastern China.
Specific conductivity is an increasingly important stressor for freshwater ecosystems. Interacting with other environmental factors, it may lead to habitat degradation and biodiversity loss. However, it is still poorly understood how the effect of specific conductivity on freshwater organisms is confounded by other environmental factors. In this study, a weight-of-evidence method was applied to evaluate the potential environmental factors that may confound the effect of specific conductivity on macroinvertebrate structure communities and identify the confounders affecting deriving conductivity benchmark in Hun-Tai River Basin, China. A total of seven potential environmental factors were assessed by six types of evidence (i.e., correlation of cause and confounder, correlation of effect and confounder, the contingency of high level cause and confounder, the removal of confounder, levels of confounder known to cause effects, and multivariate statistics for confounding). Results showed that effects of dissolved oxygen (DO), fecal coliform, habitat score, total phosphorus (TP), pH, and temperature on the relationship between sensitive genera loss and specific conductivity were minimal and manageable. NH3-N was identified as a confounder affecting deriving conductivity benchmark for macroinvertebrate. The potential confounding by high NH3-N was minimized by removing sites with NH3-N > 2.0 mg/L from the data set. Our study tailored the weighting method previously developed by USEPA to use field data to develop causal relationships for basin-scale applications and may provide useful information for pollution remediation and natural resource management.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|College of Water Science, Beijing Normal University, Beijing, 100875, China.
Xiaobo
X
Jia
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|College of Water Science, Beijing Normal University, Beijing, 100875, China.
Qian
Q
Zhao
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
Fen
F
Guo
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.
Shuqin
S
Ma
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. zhangyuan@craes.org.cn.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. zhangyuan@craes.org.cn.
Yuan
Y
Zhang
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Laboratory of Riverine Ecological Conservation and Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|College of Environment, Liaoning University, Shenyang, 110036, China.
Xiaomiao
X
Zang
D059001:Aquatic Organisms; D044822:Biodiversity; D002681:China; D003247:Conservation of Natural Resources; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005243:Feces; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis; D045483:Rivers / Q000737:chemistry*; D013696:Temperature; D014871:Water Microbiology
D010758:Phosphorus; D009584:Nitrogen
Conductivity; Macroinvertebrate; Potential confounders; Salt-intolerant; Weight-of-evidence method