Assessments Of Impacts Of Climate Change And Human Activities On The Runoff From The Fenhe River Basin Into The Yellow River

Under the influence of human activities and climate changed, The runoff of the Fenhe River flows into the Yellow River(RRY) reduced significantly, This exacerbated the situation of the shortage of water resources and led to the deterioration of ecological environment, Shanxi Province. At same time, the decrease of RRY maked the runoff of the Yellow River reduced and exacerbated the water resources shortage of the middle area of the Yellow River. Therefore, It is important to alleviate water shortages, develop the soil and water conservation measures and regional water policy through analyzing the influence of human activities and climate changed on the basis of analyzing change feature of the runoff of the study area. This paper relies on the lesson 4 crosshead project 7 of the "12th five-year" national science and technology support plan, which is " The analysis of the reason of the declines of the runoff of the Fenhe River flows into the Yellow River "(2012 BAB02B0407). On the premise of determining the influence factors which led to the decrease of RRY, based on the principle of water balance, used statistical methods and watershed hydrological model, this paper quantified the amount of decrease of RRYwhich caused by human activities and climate changed using statistical methods and watershed hydrological model. The main research contents and results of this paper are as follows:(1)Based on statistical methods such as M-K test, pettitt test, et al. The trend of the measured runoff were analyzedof Jingle station, Zhaishang station, Lancun station, YiTang station and Hejin station which located in the main stream of Fenhe River. The significantly decrease trend were found in the five hydrological station, especially the decrease trend of RRY, and the mutation point were found on the 1971, The meanvariance of runoff which calculated by runoff Before and after the mutation point were difference considerably.(2)The data of LUCC, water conservancy project, coal mining, the water level and burial depth of groundwater, the water extracted by human and meteorologicalsuch as precipitation, air temperature, wind speed et al, were collectd and arranged. Based on the principle of the formation of runoff andthe hydrologic cycle, the human activities and climate changed impacted on runoff wereanalyzed qualitatively. The main factors which caused the decrease of RRY were ascertained.(3)In order to accurate separated the influence which caused by LUCC on the runoff, Combined with the different intensity of human activities of different area, the area which controlled by Jingle station was selected to analyze hydrological response of LUCC employing SWAT model and the model which considered the LUCC and infiltration-saturation excess runoff mechanisms, the influence caused by LUCC on the runoff was analyzed quantitatively. The result showed that the LUCC led to decrease of the surface runoff and evapotranspiration,but increase the amount of groundwater and Soil lateral flow; On the whole,under the impact of LUCC, the peak flow was decrease and the flood volume was increase.(4)in order to split the influencing quantity caused by the main factors which led to decrease of RRY, The unified framework was established based on the principle of water balance, Within the framework, the influencing quantity caused by the main factors which led to decrease of RRY were calculated employing different methods such as the catchment water-energy balance equation, watershed hydrological model et al. and on the based of result of LUCC impact on runoff, which studied in the typical area, the impact of LUCC on runoff was calculated employing the method of area ratio in the Fenhe River basin. human activities was a more important factor is that caused the decrease of RRY than climate changed, contributed 83.09% of the total reduction of RRY, Groundwater exploitation gave the greatest contribution to the decrease of RRY in the scope of several kinds of human activity, 30.09%; Followed by coal mining,was 26.03%; climate changed contributed 19.17% of the total reduction of RRY, the decrease of precipitation contributed 20.81% of the total reduction of RRY,but the change of air temperature and wind speed et al led to increase of the amount of RRY.