Sensible Quality Evaluation And Classification For Slow-flowing Watercourses In Urban Area

Nowadays, the main function of urban slow-flowing watercourses is the landscape appreciation function, with the urban slow-flowing watercourses were affected by all kinds of pollutants, led to a decline in the urban watercourse sensible quality, which had a negative impact on the living environment and ecological environment of the city. The problem of watercourse apparent pollution had been caused widespread attention by a part of scholars, government departments and urban residents, the existing watercourse quality and the apparent extreme pollution water evaluation methods were not applied in the accurate evaluation of the urban watercourse sensible quality. The research took Suzhou urban slow-flowing watercourses as a case, first of all,we discussed how to evaluate the urban watercourse sensible quality scientifically and reasonably, then the research elaborated from what level, according to different situation, what kind of analysis method that can evaluate the urban watercourse sensible overall and the specific situation quality, the classification type of water sensible pollution was further improved and optimized. the rationality and applicability of the watercourse sensible pollution classification type was verified. Finally, according to different sensible pollution watercourses, put forward the corresponding improvement and control measures. This study reached the following conclusions:(1) Absorption Spectrometry Characterization method is more applicable for the watercourse sensible quality evaluation after comparison and selection. The Suzhou urban watercourses were segmented with patch reasonably, watercourse monitoring section and sampling points were arranged scientifically, determine the suitable monitoring frequency, then Absorption Spectrometry Characterization method was applied in the urban watercourse sensible quality is more accurate and reasonable, it can clear reflect the urban watercourses apparent overall and the specific situation, in order to provide theoretical guidance and technical support for the application and the promotion in other cities.(2) From the overall analysis, the patch comparison and typical watercourse three aspects, the paper demonstrated the watercourse SPI value which evaluate the urban watercourse sensible quality. Using the statistical method, through account the change which the watercourses sensible quality grade distribution in the whole monitoring period, account the distribution situation which the watercourse SPI value was less than 45, and account the cumulative frequency distribution of the watercourse SPI value, those were be used to analysis Suzhou urban watercourses the overall sensible quality. When block monitoring section less and the watercourse sensible quality was relatively stable, the paper used the analysis method which the watercourse SPI is less than the setting value, and contrasted the differences block the watercourse sensible quality overall situation macroscopically. In addition, the research monitored urban watercourse SPI value with the change of time, which reflected the variation of specific watercourse sensible quality.(3) The classification type of watercourse sensible pollution was further improved and demonstrated, the improved organic leading sensible pollution watercourse which the main condition was defined as UV254?S2-?1000 >10 cm-1?mg·L-1, minor condition Im>10mg/L, DO<2mg/L; The inorganic leading watercourse was defined as turbidity/Im>5NTU/(mg L-1),limit condition DO>2mg/L, Im<10mg/L?turbidity>20NTU, Chla<20ug/L; The nutrition leading watercourse was defined as Chla>20ug/L, limit condition turbidity/Im<5NTU/(mg/L), UV254·S2-·1000<10cm-1·mg/L; the mixed polluting watercourse was defined as SPI>10, UV254·S2-·1000<10cm-1·mg/L, turbidity/Im<5NTU/(mg/L), Chla<20ug/L.