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For inconsistency phenomenon of tide level data series of tidal reach of downstream for Qinhuai River, we take the annual highest tide level from 1947 to 2010 of Nanjing Xiaguan Station for example, analyze its wavelet to determine energy cycle of the series, and make consistency correction on the series with the use of the extracted trend term of each year for tide level data. Analyze the correlativity between the tide level datum of Qixiang estuary and Jiuxiang estuary into the Yangtze River from Nanjing Station and the Qinhuai East River, establish prediction model of tide level into the Yangtze River estuary from the Qinhuai East River through regression analysis, and make use of the corrected tide level series to predict the high and low tidal levels into the Yangtze River estuary from the Qinhuai East River. The results show that this method corrects the rising trend of tide level data of many years for the measured data, the established regression model can achieve better prediction accuracy.1

To learn about the changing trend of water resources quantity in the Yangtze River Delta, make rational allocation of water resources, and prevent regional drought & flood risks, the spatial and temporal distribution characteristics of precipitation and drought & flood in the Yangtze River Delta were investigated. Sliding average method, standardized precipitation index method (SPI), and inverse distance weighted interpolation method (IDW) etc. were used to analyze the hydrologic characteristics of YRD based on the daily precipitation data from 15 national meteorological stations in the Yangtze River Delta during the period from 1960 to 2010. According to the result: (1) The Yangtze Delta exhibited a gradually increasing trend of annual precipitation, while the flood frequency has been higher than drought frequency over the past 51 years; (2) At the Yangtze Delta, the maximum mean precipitation was normally observed in June, the minimum mean precipitation in December, the highest flood frequency in April and July, and the highest drought frequency in March; (3) The precipitation gradually increased from north to south at the Yangtze Delta, spatially, the precipitation was more evenly distributed in the north than in the south; the flood prone area was larger than drought prone area at the Yangtze Delta with West Hangzhou, East Shaoxing and West Ningbo susceptible to both drought and flood.1