Various Inflows to Taihu Lake in Autumn: Spectroscopy Characteristics and DOM Flux
It has been noted that higher concentrations of DOM (dissolved organic matter) in Taihu Lake appeared in autumn than usual,so surveys were conducted in this season with respect to the inflow water into the Lake including river water,rainwater,STPs' (sewage treatment plants) influents/effluents and sewages directly discharged into the Lake,with instruments of three-dimensional fluorescence spectroscopy and UV-visible spectroscopy analyzing DOM components and the relative parameters,tracing their sources and evaluating their impacts on DOM in the lake water.The survey suggested that DOM characteristics of varied water sources differed remarkably in spectroscopy-concentration ofρ(TOC) ((68.5±13.9) mg/L) of STPs' influent (untreated sewage) was significantly higher than other types of water.Furthermore,lake-water in the north part of the Lake (ρ (TOC)=(27.9±2.35) mg/L) had complicated compositions,dominated by humus matters and high level of protein substance.On the other hand,average value off450/500 of DOM of rainwater was 1.61,indicating the exogenous feature of high fulvic-like substances with relatively simple components and structure; and the value off4450/500 of DOM in the east part of the Lake was within the range from 1.73 to 1.92,showing an origin of endogenous biological degradation,also indicating the essential difference between the phyto-typed lake and algal typed lake in terms of source and composition of DOM.Regarding the contribution of external sources from different inflows to the DOM in Taihu Lake,the ranking was river water ＞ rainwater ＞ STPs' effluents ＞ directly discharged domestic sewage; river water carried the most DOM (2.42×108 kg/a) into the Lake with complicated compositions,impacting water quality in terms of DOM the most of the external sources.
NETL
NSTL
万方数据
维普
