Study On The Impact Of Climatie Change And Human Activities On Water Resources

Since the 1970s, the global climate has changed immensely and human's activities have increased notably, which have greater influence on water resources. The climate changes will change the current condition of the global hydrologic cycle and lead to the rearrangements in space and time and changes in quantity of water resources, which have a direct impact on rainfall, evaporation, runoff, soil humidity and so on. Besides, these huge changes will also result in the aggravation of hydrologic cycle and affect the regional water resources. Human's activities are likely to influence mechanism of runoff producing and confluence through changing watershed underlaying surface and have a deep impact on river runoff. In recent years, with the combined effects of the frequent increases of human's activities and the strong erosion of natural factors, runoff decreased and seasonal cutoff in the Northern Luo River Basin have became more and more serious, which seriously affected water resources development and utilization.Therefore, studying the effects of climate changes and human's activities on water resources of the Northern Luo River Basin have great significance to the layout, the operation management and the reasonable exploitation of regional water resources. What's more, the study will be vitally beneficial to build the water saving society. The main results are as follows:1)Variation trends of hydro-meterological factors such as precipitation, evaporation and runoff in the Northern Luo River basin were analyzed with moving average method and Spearman rank correlation method respectively. The results show that they are all declining.2)This paper analyzed the runoff time series from 1959 to 1999 of the Liujia River and Jiaokou River hydrological station on the Northern Luo River by R/S analysis method.The results show that 1978 is the transition point of hydrological series of the Northern Luo River Basin, and human activities have affected significantly on hydrology of the Northern Luo River Basin after 1978.3)Using the hydrological and meteorological data in natural environment, the BP neural network model parameters were calibrated first,then kept the model parameters constant, the natural runoff in human activities affect period was gotten through inputting the hydrologic meteorological data in the human activities affect period.4)Using the actual measurement and reduction of natural runoff, this paper analyzed the effects of climate change and human activities on runoff of the Northern Luo River Basin by Quantitative separation method for individual effect of climate change and human activities on runoff. And results show that climate changes are the main reason of runoff reduction in recent years.