Study On The Influence Of Water Cycle And Quantitative Assessment In The Daqing River Basin

Global climate change and human activity has caused water space-time distribution andthe change of the regional water resources. it has an impact on water resources,socio-economic development and ecological systems，analyzing the reason of runoff change isthe effective measure to alleviate water crisis. The Daqing river basin is the main watersources to resident living、industrial and agricultural production in Hebei province，TheDaqing river basin is directly related to the sustainable development of social economy andecological environment。With two sub-basin of Zhangfang hydrological station upstreambasin and Xi Dayang reservoir upstream basin as the research object, Quantitative analyze thecontribution rate of climate change, land use/cover change and hydraulic engineering’et alhuman activities to the runoff, it reveals the main factors of the Daqing river basin runoffreduction. It not only provides a scientific basis for water resources reasonable developmentand socio-economic sustainable development in the Daqing river basin, but also provides asolid technical foundation to the research in other water system of Haihe river basin.Calculation of rainfall and temperature series based on the selected eight nationalmeteorological stations by area weighted average method in the Zhangfang hydrologicalstation upstream basin and Xi Dayang reservoir upstream basin. Analysis of trends andmutation of the average annual rainfall and temperature by linear tendency variation and M-Kexamination. The study period is divided into the base period (1967-1980), evaluation periodⅠ(1981-1989), evaluation period Ⅱ(1990-2004) and evaluation period Ⅲ(2005-2010). Theapplication of SWAT hydrological models and separating judgment method, Likelycontributions from various factors of the Runoff changes are quantitatively analyzed. Thesefactors include the climate change, land use and coverage changes, hydraulic engineering’et alhuman activities. The results include:(1) The period from1967to2010year, Rainfall and runoff showed a downward trend inthe Zhangfang hydrological station upstream basin and Xi Dayang reservoir upstream basin.Rainfall decline is not obvious, was a cyclical changes. runoff depth decreased significantlyafter1982, the mutation of time sequence is1982in the Zhangfang hydrological station, theXi Dayang reservoir is1982and1989. Two basin temperature is on the rise, the mutation of time sequence is1982in the two basin, temperature rose significantly after2005.(2) Rainfall and runoff depth has a good correlation, rainfall is the main climate factor tolead to reduce runoff, Relative to the base period, the contribution rate of the climate changeto runoff is8%(periodⅠ),9%(periodⅡ),12%(periodⅢ) in the Zhangfang hydrologicalstation upstream basin, the Xi Dayang reservoir upstream basin is16%(periodⅠ),19%(periodⅡ),31%(periodⅢ). Although the contribution rate of the climatechange to runoff is small, Climate change has a long-term influence on the Daqing river’swater cycle, and it is more and more obvious.(3) Relative to the base period, the contribution rate of the LUCC to runoff is33%(periodⅠ),39%(periodⅡ),36%(periodⅢ) in the Zhangfang hydrological stationupstream basin, the Xi Dayang reservoir upstream basin is38%(periodⅠ),47%(periodⅡ),24%(periodⅢ). After the reform and opening-up policy, Rural land policy reform, a lot ofterraces were Build in1990s, Cultivated land area and urbanization is increasing rapidly,Transition deforestation and grazing leads to the reduce of woodland and grassland, With the1980land-use conditions, land use structure has significant changes in Daqing river basin, itwas a major factor to reducing runoff.(4) For Zhangfang upstream basin, Annual water consumption is respectively3394,9449,17660,21559million cubic meters in base period (1967-1980), periodⅠ(1981-1989),periodⅡ(1990-2004) and periodⅢ(2005-2010). the Xi Dayang reservoir upstream basin is5659,10213,12290,23387million cubic meters. the contribution rate of the hydraulicengineering’et al human activities to runoff is33%(periodⅠ),39%(periodⅡ),36%(periodⅢ)in the Zhangfang hydrological station upstream basin, the Xi Dayang reservoir upstream basinis38%(periodⅠ),47%(periodⅡ),24%(periodⅢ). Annual water consumption is graduallyincreasing in Daqing river basin Although the contribution rate is not increased, it was a majorfactor in reducing runoff.(5) The main factors of land use/cover change is dramatic impact of human activities,the sum of the contribution rate of land use/cover change and hydraulic engineering’et al torunoff show the contribution rate of human activities to runoff. Relative to the base period, thecontribution rate of the human activities to runoff is92%(periodⅠ),91%(periodⅡ),88%(periodⅢ) in the Zhangfang hydrological station upstream basin, the Xi Dayang reservoir upstream basin is84%(periodⅠ),81%(periodⅡ),69%(periodⅢ). Human activities was amajor factor to reducing runoff in Daqing river basin. the contribution rate is reduced, It isreason that the contribution rate of the climate change to runoff is increased.Finally, some ideas are raised to Water resources management and planning in theDaqing river basin. And lack of on the article as well as possible research issues in the futurewere briefly discussed.