title: Impact of extreme oxygen consumption by pollutants on macroinvertebrate assemblages in plain rivers of the Ziya River Basin, north China.
abstract: The aim of the study was to estimate the impact of oxygen depletion on macroinvertebrate community structure in benthic space. Macroinvertebrate assemblages and potential of dissolved oxygen (DO) consumption were investigated simultaneously in the plain rivers of the Ziya River Basin. The degree of DO depletion was represented by sediment oxygen demand (SOD) and DO, chemical oxygen demand (CODCr), and ammonia nitrogen (NH4 (+)-N) in the overlying water. The results showed an all-around hypoxia environment formed, and the values of DO, SOD, CODCr, and NH4 (+)-N were separately 0.11-4.03 mg L(-1), 0.41-2.60 g m(-2) day(-1), 27.50-410.00 mg L(-1), and 1.79-101.41 mg L(-1). There was an abnormal macroinvertebrate assemblage, and only 3 classes, Insecta, Gastropoda, and Oligochaeta, were found, which included 9 orders, 30 families, and 54 genera. The biodiversity was at a low level, and Shannon-Wiener index was 0.00-1.72. SOD, and NH4 (+)-N had major impact on the macroinvertebrate community, and the former had negative effect on most taxa, for instance, Nais, Branchiura, Paraleptophlebia, etc., which were sensitive or had a moderate-high tolerance to pollution. NH4 (+)-N had both positive and negative impacts on benthic animals, for instance, Dicrotendipes, Gomphus, Cricotopus, etc., for the former, and Procladius, Limnodrilus, Hippeutis, etc., for the latter. They all had a moderate-high tolerance to pollution. It is significant to improve DO condition and macroinvertebrate diversity in river harnessing and management.
authors.affiliation: State Key Laboratory on Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Science, Beijing, 100085, People's Republic of China.|University of Chinese Academy of Science, Beijing, 100049, People's Republic of China.
authors.forename: Yuekui
authors.initials: Y
authors.lastname: Ding
authors.affiliation: State Key Laboratory on Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Science, Beijing, 100085, People's Republic of China.|University of Chinese Academy of Science, Beijing, 100049, People's Republic of China.
authors.forename: Nan
authors.initials: N
authors.lastname: Rong
authors.affiliation: State Key Laboratory on Environmental Aquatic Chemistry, Research Center for Eco-Environmental Science, Chinese Academy of Science, Beijing, 100085, People's Republic of China. bqshan@rcees.ac.cn.
authors.forename: Baoqing
authors.initials: B
authors.lastname: Shan
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis; D000693:Anaerobiosis; D000818:Animals; D044822:Biodiversity; D057919:Biological Oxygen Demand Analysis; D002681:China; D004784:Environmental Monitoring; D007448:Invertebrates; D009835:Oligochaeta; D010100:Oxygen / Q000032:analysis; D010101:Oxygen Consumption; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry; D014876:Water Pollution / Q000009:adverse effects*
chemical_list: D064751:Ammonium Compounds; D014874:Water Pollutants, Chemical; D010100:Oxygen
keywords: Macroinvertebrate; Oxygen consumption; Ziya River Basin