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1.
将模糊信息分配方法应用到水质评价中。该方法是从原始数据信息中直接构造系统模型 ,尽可能保留原始数据结构的完整性。它与模糊一、二级近似推论构成一套完整的评价方法。用该方法对西安市地面水水质进行评价 ,结果表明评价结果能较准确地反映水质的实际情况 ,具有一定的应用价值。同时提出一种新的水质分级方法  相似文献   

2.
Hyper-spectrum models for monitoring water quality in Dianshan Lake,China   总被引:1,自引:0,他引:1  
The correlation between water quality parameters and hyper-spectral reflectance is studied with models established for each parameter and applied in Dianshan Lake, in the upstream of the Huangpu River running through Shanghai, China. Models are for dissolved oxygen (DO in mg/L): R720/R680 = 20.362×(R720/R680)2-31.438×(R720/R680)+19.156; for turbidity (NTU): R*714.5 = 206.07× (R*714.5)2-582.5×R*714.5 + 423.24; and for total phosphorus (TP in mg/L): R*509.5 = 16.661× (R*509.5)2-32.646×R*509.5+16.116. The R2 values are 0.770 8, 0.660 4 and 0.738 7, respectively, showing strong positive relationships. The models were then applied to assess water quality of different times. Results are quite satisfactory for some samples.  相似文献   

3.
DYNAMIC VARIATIONS OF WATER QUALITY IN TAIHU LAKE AND MULTIVARIATE ANALYSIS OF ITS INFLUENTIAL FACTORSDYNAMICVARIATIONSOFWATE...  相似文献   

4.
Water quality assessment of lakes is important to determine functional zones of water use. Considering the fuzziness during the partitioning process for lake water quality in an arid area, a multiplex model of fuzzy clustering with pattern recognition was developed by integrating transitive closure method, ISODATA algorithm in fuzzy clustering and fuzzy pattern recognition. The model was applied to partition the Ulansuhai Lake, a typical shallow lake in arid climate zone in the west part of Inner Mongolia, China and grade the condition of water quality divisions. The results showed that the partition well matched the real conditions of the lake, and the method has been proved accurate in the application.  相似文献   

5.
1INTRODUCTIONTheWestLake ( 30°1 5′N ,1 2 0°1 6′E)isasmallshallowlakeinthewesternpartofHangzhouCityinthesoutheasterncoastalareaofChina.Thelakeissur roundedonthreesidesbyhills ;andisfamousforitspicturesquesceneryandinterfusionofhillsandwaterbodies.Thesurfaceareaisabout 5 .66km2 andmeandepthis 1 .8m .Beforethe 1 95 0s ,thelakewaterwascleanandmacrophytesgrewveryluxuriantlyinthelit toralareasofthelake .In 1 95 2 ,WestLakewasdredgedand 70 0× 1 0 4m3 mudwasremovedfromthebottomofthelake …  相似文献   

6.
WATERQUALITYANALYSISANDASSESSMENTOFRIVERSINJILINPROVINCEOFCHINA¥WangJun(王俊)ZhaoBaozhong(赵宝中)(DeportmentofEnvironmentScience,N...  相似文献   

7.
1 INTRODUCTION Dongting Lake (28°18'–29°45'N, 111°35'– 113°18'E) is the second largest freshwater lake in China, and directly connected with the Changjiang River (Yangtse River) through the channel. The sur- face area was about 2 740 km2 (at the low  相似文献   

8.
在选择了各污染物的“参照值”情况下,用污染物的实测学相对值代替水质污染损害率公式中的浓度监测值,公式中的参数可认为与污染物的特性无关。采用遗传算法优化中的参数,得到了多种水质污染物都能适用的水质污染损害率和污染损害指数公式。提出用对比加权对污染损害分指数进行赋权的新方法,计算水质综合污染损害指数。该方法用于水质综合评价的物理意义明确、计算简单、使用方便,具有普适性和可比性。  相似文献   

9.
WATERRESOURCESTRANSFORMATIONANDWATERQUALITYVARIATIONINTHEURUMQIRIVERBASINQuYaoguang(曲耀光);LuoHongzhen(骆鸿珍)(LanzhouInstituteofG...  相似文献   

10.
To study the relationship between zooplankton community structure and environmental factors and water quality in the Harbin Section of the Songhua River, investigations were carried out in June, August, and October 2011. Canonical correspondence analysis (CCA) and saprobic indices were used to process and analyze the data. Seasonal variability was identified as a significant source of variation, which explains the fluctuation in zooplankton density. In autumn, the dry season, water residence time increased and zooplankton biomass and abundance accumulated in the slow flowing waters. Zooplankton abundance increased when food conditions improved. Therefore, the total zooplankton abundance in autumn is much higher than that in spring and summer. According to the saprobic indices, all the sample sites had mesosaprobic water and water quality was worse in autumn. CCA revealed that temperature accounted for most of the spatial variation in the zooplankton community. Moreover, pH, dissolved oxygen saturation, and turbidity were important factors affecting zooplankton community distribution.  相似文献   

11.
AMULTI-WINDOWGISAPPROACHFORWATERQUALITYDATAANALYSISLinHui(DepartmentofGeography,TheChineseUniversityofHongKong,Shatin,NewTerr...  相似文献   

12.
The underground water qualitymodel with non-linear inversion problem is illposed, and boils down to solving the minimum of nonlinear function. Genetic algorithms are adopted in a number of individuals of groups by iterative search to find the optimal solution of the problem, the encoding strings as its operational objective, and achieving the iterative calculations by the genetic operators. It is an effective method of inverse problems of groundwater, with incomparable advantages and practical significances.  相似文献   

13.
The underground water quality model with non-linear inversion problem is ill-posed, and boils down to solving the minimum of nonlinear function. Genetic algorithms are adopted in a number of individuals of groups by iterative search to find the optimal solution of the problem, the encoding strings as its operational objective, and achieving the iterative calculations by the genetic operators. It is an effective method of inverse problems of groundwater, with incomparable advantages and practical significances.  相似文献   

14.
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality.  相似文献   

15.
Phytoplanktonic desmids community in Donghu Lake, Wuhan,China   总被引:1,自引:0,他引:1  
1 INTRODUCTION Donghu Lake (30o33′N, 114o23′E) is a shallow medium sized freshwater lake in Wuhan City, Hubei Province, China and about 5 kilometers away from the Changjiang (Yangtze) River. Before the 1960s, the water surface area was about 27.8 km2. The lake water was clear and the pH ranged from 6 to 7. The shallow area of the lake abounded with macrophytes. The phytoplanktonic and peripheral desmids were very abundant also in this lake. In the late 1960s, Donghu Lake with tota…  相似文献   

16.
For the Pinang River, originating in the western highlands of Penang Island, the nature, sources and extent of pollution were studied. The river water samples collected at five selected sites were analyzed for various physical and chemical parameters, namely temperature, DO, BOD, COD, SS, pH, ammoniac nitrogen (AN), and conductance. Long-term data of rainfall and temperature were analyzed to determine the seasonal variations of the streamflow.The streamflow during the dry season is extremely low compared to the wet season, thus concentrations of contaminants derived from point pollution source increase due to lack of rainfall and runoff events. On the contrary, in the predominantly urban and agricultural catchments, non-point pollution source increases during rainy season through seepage and runoff. Effects of seasonal variations consequently deterrnine the quantity and quality of the water parameters.The Jelutong River, the Dondang River and the Air Itam River carry the seepage from widely urban and residential areas to the main Pinang River systems. Water quality of the Pinang River at different points assessed by the water quality indices was compared. According to the quality indices during the study period, water quality in the upper reaches of the river is medium to good. It dwindled in the plains, due to the seepage from urban areas and discharges from the industrial and agricultural lands.  相似文献   

17.
Flow cytometric determinations of the abundance distribution and community structure of picophytoplankton (i.e.,Prochlorococcus spp.,orange fluorescence Synechococcus spp.and picoeukaryotes) were used for samples taken from the Philippine Sea in the western tropical Pacific Ocean from September to October of 2004.A fluorescence probe was employed to detect Chlorophyll a (Chl a).Abundances of Prochlorococcus spp.,orange fluorescence Synechococcus spp.and picoeukaryotes ranged from 0.1 to 58×103 cells ml-1,0.38 to 17×102 cells ml-1 and 0.42 to 26×102 cells ml-1,respectively.Synechococcus spp.and picoeukaryotes co-occurred in relatively shallow water with the maximum abundance observed at 50 to 70 m depth,while Prochlorococcus spp.only occurred in the 70 to 200 m layer.Prochlorococcus spp.was the dominant picophytoplankton population in terms of abundance and biomass.The cell size and carbon biomass content were estimated for the three picophytoplankton groups.In addition,among the three groups of picophytoplankton,the relative contribution of red fluorescence to the total red fluorescence varied with depth.The fluorescence and light scatter properties of individual cells indicated that in the upper 100 m layer,picoeukaryotes were a major contributor to total red fluorescence,while at the depth below 100 m,Prochlorococcus spp.and Synechococcus spp.made an important contribution to the total red fluorescence.  相似文献   

18.
适用于多指标的水环境质量评价的普适指数公式   总被引:1,自引:0,他引:1  
在适当设定水质指标的“基准”值情况下,用相对于“基准”值的指标相对值替换对数形式的指数公式中的水质指标值,采用遗传算法优化不同指标的指数公式中的参数,得到对多项指标通用的水质普适指数公式;并用折衷型激励功效函数将单项指标的指数加权为综合指数。公式的正确性已被用于多处水质评价检验所证实。该公式形式简单,易于计算,使用方便;具有客观性、可比性和通用性。  相似文献   

19.
提出了基于s型生长曲线函数的地下水水质评价的污染损害率公式,并采用粒子群优化算法对水质污染损害率公式中的参数进行优化.将优化好的水质污染损害率公式用于某地20个采样点地下水水质评价,并与其它评价方法的评价结果进行了比较,结果表明公式能较好地用于地下水水质的综合评价,有明确的物理意义,简单适用,并具有一定的普适性.  相似文献   

20.
天山北麓蓄水构造模式与水循环特征   总被引:4,自引:0,他引:4  
从控制地下水形成的地形地貌、地质构造出发,探讨了新疆天山北麓串珠式、隐伏串珠式、隆起间歇式、连续式和山间谷地式5种蓄水构造模式.提出大气降水、地表水和地下水(土壤水)相互转化一次循环、两次循环和多次循环类型,在此基础上研究水资源开发利用不同方式,为指导天山北麓水资源合理开发利用与生态环境保护提供技术依据。  相似文献   

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