title: Effects of organic matter content and composition on ammonium adsorption in lake sediments.
abstract: The nature of the influence of organic matter (OM) on ammonium adsorption in lake sediments remains disputed. In this study, the kinetics and thermodynamics of ammonium adsorption were investigated on sediment samples with different OM contents (ignoring the effects of OM mineralization) previously collected from Lake Wuli, a northern bay of Lake Taihu, a shallow lake in southern China. The mechanisms of ammonium adsorption in these samples were characterized by Fourier transform infrared spectrometry and scanning electron microscopy. The results show that the ammonium adsorption capacity of the sediments is highly correlated with their OM content and with the humic content of the OM. The ammonium adsorption capacity of OM varies with its composition, i.e., with the surface properties of the different functional groups present. Indeed, humic acid was found to have a greater ammonium adsorption capacity by itself than when mixed with kerogen and black carbon, the mixture of the latter two components proving a better adsorbent than pure black carbon.
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. wangshengruia@163.com.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China. wangshengruia@163.com.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China. wangshengruia@163.com.
authors.forename: Shengrui
authors.initials: S
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Jiao
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Jiachun
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|State Environmental Protection Key Laboratory for Lake Pollution Control, Research Center of Lake Eco-environment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China.|Dongting Lake Ecological Observation and Research Station Chinese Research Academy of Environmental Sciences, Yueyang, Hunan Province, 414000, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D064751:Ammonium Compounds / Q000032:analysis*; D002681:China; D019015:Geologic Sediments / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D007700:Kinetics; D060106:Lakes / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D013499:Surface Properties; D013816:Thermodynamics; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D064751:Ammonium Compounds; D006812:Humic Substances; D014874:Water Pollutants, Chemical
keywords: Adsorption; Ammonium; Fourier transform infrared spectrometry; Organic matter; Scanning electron microscopy; Sediment