title: Effect of wave-current interactions on sediment resuspension in large shallow Lake Taihu, China.
abstract: The disturbance of the water-sediment interface by wind-driven currents and waves plays a critical role in sediment resuspension and internal nutrient release in large, shallow lakes. This study analyzed the effects of the interactions between wind-induced currents an1d waves on the driving mechanism of sediment resuspension in Lake Taihu, the third largest freshwater lake in China, using acoustic and optic techniques to collect long-term, high-frequency, synchronous in situ measurements of wind, currents, waves, and suspended solid concentrations (SSCs). The results suggested that water turbidity started to increase at wind speeds of approximately 4 m/s and significantly increased when wind speeds exceeded 6 m/s. In most cases, wind-induced waves were the main energy source for changes in turbidity. Wave-generated shear stress contributed more than 95% to sediment resuspension and that only in weak wind conditions (<4 m/s) did the lake bottom shear stresses generated by currents and waves contributed equally. The relationship between SSC and bottom shear stress generated by wave was established by fitting the observed results. The processes of sediment dynamics were divided into four stages (A through D) according to three shear-stress thresholds. In stage A, SSC remained stable (about 45 mg/L) and τwwas less than 0.02 N/m2. In stage B, the sediment bed was starting to be activated (SSC 45∼60 mg/L) and τwwas in the range of 0.02∼0.07 N/m2. In stage C, a medium amount of sediment was suspended (SSC 60∼150 mg/L) and τwranged from 0.07 to 0.3 N/m2. In stage D, large amount of sediment was suspended (SSC 150∼300 mg/L) and τwwas larger than 0.3 N/m2. The findings of this paper reveal the driving mechanism of sediment resuspension, which may further help to evaluate internal nutrient release in large shallow Lake Taihu.
authors.affiliation: Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing, 210098, China.|College of Environment, Hohai University, Nanjing, 210098, China.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Environment, Hohai University, Nanjing, 210098, China. chyt_06141208@126.com.|Environmental Process Modelling Centre, Nanyang Environmental and Water Research Institute, Nanyang Technological University, Singapore, 637457, Singapore. chyt_06141208@126.com.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Tang
authors.affiliation: College of Environment, Hohai University, Nanjing, 210098, China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Division of Hydrologic Sciences, Desert Research Institute, Las Vegas, NV, 89119, USA. Kumud.Acharya@dri.edu.
authors.forename: Kumud
authors.initials: K
authors.lastname: Acharya
authors.affiliation: College of Environment, Hohai University, Nanjing, 210098, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.affiliation: College of Environment, Hohai University, Nanjing, 210098, China.
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Liancong
authors.initials: L
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Huiyun
authors.initials: H
authors.lastname: Li
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, 210008, China.
authors.forename: Shujun
authors.initials: S
authors.lastname: Dai
authors.affiliation: College of Environment, Hohai University, Nanjing, 210098, China.
authors.forename: Jepkirui
authors.initials: J
authors.lastname: Mercy
authors.affiliation: State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.
authors.forename: Zhongbo
authors.initials: Z
authors.lastname: Yu
authors.affiliation: Changjiang River Scientific Research Institute, Wuhan, 430010, China.
authors.forename: Baozhu
authors.initials: B
authors.lastname: Pan
mesh_terms: D002681:China; D019015:Geologic Sediments / Q000032:analysis*; D060106:Lakes; D014919:Wind
keywords: Sediment resuspension; Shallow lake; Shear stress; Wind-induced current; Wind-induced wave