| Climate change and human activities impact are two topics in the current evolution law research of hydrology and water resources. The water circular system is an important part of the climate system, and climate change must cause water resources change in temporal and spatial. However, human activities are the most important factors in watershed hydrologic cycle system. On the one hand, land use changes and construction of large hydraulic engineering make the basin underlying surface changed, and then affect the runoff yield and concentration mechanism; on the other hand, industrial and agricultural water use and inter-basin water transfer affect the temporal and spatial distribution of water resources directly.Current water resources system has changed enormously. It has important significance to quantify the influence of climate change and human activities for the cognition of evolution law and sustainable development of water resources. In view of this situation, this paper carries out the evolution law study of water resources based on large-scale distributed hydrological model. Research contents and results are as follows:(1) Change characteristics analysis of hydrometeorological factors in typical basin. Many trend test and change-point analysis methods are used to analyze the change tendency and change-point recognition of hydrometeorological factors in the typical basin of northeast China. Based on the hydrometeorological factors recognition, the degree and change characteristics of the basin climate change and human activities can be required primarily. Results show that these methods can qualitatively recognize the change characteristics of precipitation, temperature and other factors in the typical basin.(2) Construction of large-scale hydrologic cycle model. This paper describes the structure and principle of SWAT model, and then displays the database construction for meteorology, soil and land use in detail. These works can provide vigorous support to the hydrological cycle simulation and to the quantitative analysis of climate change and human activities influence.(3) To deal with the quantitative analysis problem of historical climate change and the influence of human activities, a partial quantization method is put forward base on SWAT model. In order to weaken the interference of high and low variation of rainfall in a short period to the separation calculation of influence quantity of climate change, reducing calculation of the rainfall in the influence period of human activities is made, linear change range of climate is analyzed using complete series of rainfall data and temperature, linear change quantity of annual rainfall is reduced to practical rainfall series according to distribution proportion of every month, model parameters calibration is made using rainfall data in reference period, and runoff simulation is conducted under different rainfall condition in the period of human activities. By comparing the runoff change under different rainfall data condition in human activities influence period with that in reference period, high and low change quantity of rainfall, climate change quantity and influence quantity of human activities can be separated out, then quantitative analysis of historical climate change and human activities influence on river runoff can be realized. Taking the typical Huifa river basin as the study area to validate the model, the result shows that the method proposed in this paper is successful in separating the influence quantity of climate change and human activities more reasonably.(4) To deal with the quantitative problem of the influence of human activities such as agricultural irrigation water use in irrigation district basin, a advanced water cycle model base on SWAT model is proposed. Modifications are made to calculation methods of water source irrigation and field water balance equation to calculate paddy field runoff, the judgment criterions of irrigation in ponding period and rice growth period are defined respectively, so that the multi-water resources irrigation mode can be put into effect in both periods. Taking Huntai basin irrigation district as the study area to validate the irrigation district simulation model, by remodeling river flow under irrigation condition or without irrigation condition, calculating the ratio of irrigation water regression, irrigation influence coefficient, to quantize influencing of irrigation on river flow and water cycle factors.(5) To deal with the uncertainty of forecast results of single climate model in the study of future climate change influence on water resources, a REV-BMA based GCM Multi-mode weighted average method for climate data processing is proposed, which explicitly relates SWAT hydrological model in large-scale basin to research the influence of future climate change on water resources. First, two downscaling methods, automated statistical downscaling (ASD) and interpolation distance weight (IDW) are applied to downscale the GCMs(CGCM3,HadCM3,CSIRO,BCCR) respectively; Second, the REV-BMA method is employed to compute the weighted variable quantity of future climate in the GCM multi-model, then proportion scaling is made to the rainfall and temperature input data in reference period according to future change quantity of rainfall and temperature, and applied SWAT to simulation. Finally, taking Huntai River basin as the study area, establish climate change on water resources impact assessment model (REV-BMA-SWAT) to assess the change of dahuofang reservoir inflow and basin hydrological cycle factors during 2011～2040, and by comparing it with the single GCM simulation, RVM model simulation, and based on history data trend simulation.
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