1Characteristics and Mechanism of Precipitation and Groundwater Exploitation Influence on Groundwater Flow Filed in Agricultural Field HufuWANG Dian-long, FENG Hui-min, TIAN Yan-liang, ZHANG Guang-hui20-24,372Application of Principal Component Analysis in Water Quality Evaluation of Several Rivers in Haihe River BasinLIAN Tie-hui, WANG Zhao, WANG Hong-cui, LUO Yang29-31,373Contrastive Verification of Precipitation Forecasting of Four NWP Models in the Haihe River BasinXU Shu, WEI Lin, DENG Yan45-514Reasearch on UV254 Index by Ultraviolet SpectrophotometerYANG Miao-miao58-615Decision Support System of Haihe River Basin Water Resources ManagementQIU Jun-nan, LI Shu-yuan, WANG Hong-wei64-666Research and Application of the Remote Sensing and Monitoring System of Ground Source Heat Pump in TianjinXUE Zeng-xiao, ZHAO Li-li67-70