Study On The Protection And Environmental Effect Of The River Network In The Urbanization Process Of Shanghai City

River network in Shanghai are well-developed in that the city lies in a tidal plain. However, the value of water area has reduced by 25 per cent in recent 20 years during the process of urbanization and high-speed development of the urban economic in Shanghai city. It shows that the characters of river network have been obviously impacted by human activities. Along with the urbanization process of Shanghai, maintaining appropriate water surface ratio (Wp) is of great importance to the eco-environment construction of the city. Consequently, from the angle of eco-hydrology, to establish harmonious ground hydrological pattern, it will be provided with favorable researching meaning and foreground to study the protection and environmental effect of river network.This paper is based on the project of Doctor Foundation of Ministry of Education (No.: 20020269014) and the project of Shanghai Waterway Administration. The data in this paper are obtained by collecting historical literature, selecting the data from Shanghai water resources general survey, and field monitoring, etc. It qualitatively and quantitatively explores the evolution of the river network, and the Wp disparity between urban and suburb area. The paper pays great attention to the storage effect of the network and microclimate effect of urban river and waterbody. The value of appropriate Wp in Shanghai is advanced, finally the countermeasures for the protection and management of the river network is discussed in details.Based upon the division method of the water conservation zones and river order in Shanghai, we approach on the storage effect of the urban river network by the idea of the SR and ASR. It is showed in this paper that: (1) From the central district to the suburb, the storage effect of river network is gradually fortified. Yunnan and Dianbei zones make the low-value core, where is the most high-urbanization area. (2) The storage effect greatly varied with the river order. Supposing to define rivers of 1st and 2nd order as lower-order, and rivers of 3rd and 4th order as higher-order, then it is found that the higher the ratio that the available capacity accounting for total capacity in the lower-order, the greater the underlying drainage capacity will the river be. On the contrary, the total storage capacity of higher-order relatively greater, but the drainage capacity is lower as to that of lower-order rivers. (3) The differences of river storage effect among water conservation zones increased with the descending of river order. The storage effect of the higher-order rivers differentiate slightly between each zones. Since the number and the average length of rivers are reduced in Yunnan and Dianbei zone in high urbanized area, the storage effect of lower-order rivers in this two zones are significantly less than that of other zones. (4) Wp is one of the most conclusive factors for regional waterlogging control. It is calculated that Wp is significantly related with SR (R2=0.936, p<0.001) and ASR (R2=0.934, p<0.001), which shows that the storage effect depends greatly on the Wp.Six types of urban rivers and waterbodies in Shanghai urban distract have been selected for the field monitoring to the daytime temperature (T) and relative humidity (RH) of the circumjacent surroundings. By comparing temperature-humidity features and human comfortdegrees between the windward and the leeward of these selected water bodies in different seasons, this paper preliminary analyzed microclimate of urban river and waterbody, then discussing some influencing factors on it. The results obtained are as follows: (1) The value of waters area contribute greatly for the microclimate effect. In observing period, the environmental microclimate effect of lake in Changfeng Park is greater than that of other observed waterbodies, mainly attributing to the larger lake area. (2) Building layout around waterbody affects the microclimate in some degree, we say, dense high buildings in Zhongyuan residential district transformed the state of the atmosphere flow, and the mi...