Spatial And Temporal Evolution Of Water Resources In Beijing-Tianjin-Hebei Region In Recent 60 Years

Water resources are the most basic natural resources and strategic economic resources in our country.With the development of society and economy,the shortage of water resources has become a major problem for the sustainable development of our country.As a kind of renewable resources,water resources are inexhaustible in the traditional sense,but in recent years,the influence of human activities is increasing,which makes the water resources available for human use less and less.Study on the temporal and spatial evolution of water resources,can accurately understand the distribution of water resources in Beijing-TianjinHebei region and the change in the time scale and spatial trends,provide an effective basis for rational allocation of water resources in Beijing-Tianjin-Hebei region,is of great significance to solve the contradiction between supply and demand of water and water resources sustainable and healthy development.In this paper,the Beijing-Tianjin-Hebei region as the research object,the area and basin superimposed,starting from the water cycle and the evapotranspiration mechanism,using the distributed hydrological model improved(HIMS),to complete the Haihe River Basin and the Beijing-Tianjin-Hebei region overlapping basin modeling,and verify the rationality and accuracy of the improved HIMS evaporation,runoff,soil water simulation,and calculated by national water resources calculation method,and the Beijing-Tianjin-Hebei nearly 60 years of precipitation and water resources evolution analysis of space-time.The main conclusions are as follows:(1)the annual precipitation change in Beijing-Tianjin-Hebei region is large,there is a downward trend is not significant,the number of days of precipitation was significantly decreased,i.e.single precipitation increased precipitation decreased.(2)the spatial distribution of precipitation in the area of Beijing,Tianjin and Hebei is extremely uneven,and the distribution of the precipitation is more in the southeast and less in the northwest.There is a slight difference in different years.The Beijing-Tianjin-Hebei region400 mm isohyet to there is no significant eastward trend,zonal southward trend is not obvious there,600 mm isohyet to there is no obvious zonal westward trend,there is obvious southward trend.(3)the study area water resources generally declined significantly large inter annual change;water resources quantity years overall has increased,the 1.3 month of a downward trend,there is an increasing trend of 4-11 month,in August the most significant.Beijing,Tianjin and flood water resources in the non flood season,the gap between the smaller,which is not obvious decline trend in flood season,non flood season decline trend is more obvious.(4)the distribution of water resources in the study area is more in the southeast and less in the northwest,which is mainly concentrated in the vicinity of Tianjin,the northwest of Hebei Province,the southern part of Hebei province and the coastal areas.The spatial distribution of water resources in Beijing,Tianjin and Hebei Province in recent 60 years has not changed much,but the local changes are more obvious.