Research On The Characterization Method Of Apparent Pollution For Urban Water Based On Absorption Spectrum

In recent years, with the development of industrial economy and the increasingpopulation in the city, a growing number of urban water bodies have being polluted. Nicesense becomes particularly important for landscape water. However, the methods forevaluating the apparent pollution of landscape water are relatively scarce currently. Andwater quality assessment methods can not evaluate the appearance of the water bodyindependently, comprehensively and accurately. So it requires thorough research on thesensory evaluation of water body urgently. And it is necessary to establish a set ofmethods which can describe the sense of the water and be used to evaluate the apparentpollution scientifically and reasonably. It has great significance for the governance ofurban water environment.The reseach object is the urban landscape water body in this study. By measuringthe absorption spectrum curve of the water sample itself to express the subjectivefeelings of the people and the scanning curvearea is used to characterize the apparentpollution of urban landscape water. There are many conclusions through a series of testsas following:(1) The apparent pollution is mainly caused by the non-soluble contaminants, whiledissolved contaminants have less effect on the apparent pollution.(2) The area equal rate between water samples with the same color and turbidity is95%. While the color is same, the response relationship of turbidity and scanningcurvearea is very good, the linear correlation is0.95. Color and scanning curvearea havecorresponding response when the turbidity is the same. So it is feasible to characterizethe apparent pollution of landscape water using scanning curvearea.(3) The main cause of poor response between site grading and scanning curvearea isthe inconsistent impact of color.(4) By the introduction of color correction coefficient and correcting the visiblescanning curvearea, the discrimination between different apparent pollution levels isobvious. And then the response relationship of the Sensation Pollution Index (SPI) andthe revised curvearea is established, the apparent pollution index equation and gradingstandards are determined which can used to determine apparent contamination degrees ofwater samples.(5) Checking the method using131sets of water samples, The result shows that the completely consistent proportion of the evaluation degrees using this method and theactual rating results is25.19%, while the proportion of samples whose deviation is±1is53.44%, the proportion of samples whose deviation is±2is17.56%, the proportion ofsamples whose deviation is±3is3.82%. Considering the evaluation results on-site wouldbe effected by the surrounding environment and individual differences where will also bea deviation of±1, so it is reliable to characterize the apparent pollution of urbanlandscape water using scanning curvearea, the basically consistent rate is78.6%.