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Wetlands Shuangtaizihekou located in the territory of Panjin City, Liaoning Province, is China's largest coastal reed swamp area has important in regulating climate, conserving water, purify water, reduce pollution and maintain the regional ecosystem water and salt, water and heat and water sand balance, etc. effect. However, under the influence of global climate change and human activities of estuary wetland eco-hydrological process of profound change in wetland eco-hydrological pattern of disorder, led to sharp drop in wetland area, lack of ecological water, deterioration of water quality, increased soil salinization, seawater intrusion, etc. thereby constraining the sustainable development of human society in the entire basin. Reasonable repair and protection of wetlands to maintain smooth river basin development, will Shuangtaizihekou wetlands included in the basin-wide analysis, study of the changing environment based eco-hydrological simulation estuary wetland eco-hydrological regulation program, key findings are as follows: (1 ) on the basis of summarized at home and abroad wetland eco-hydrological Processes Simulation, build the technical framework of the watershed scale wetland eco-hydrological modeling and simulation strategy and DGVM (dynamic global vegetation model), WEP (distributed hydrological model) and SiB2 (simple biosphere model)-based, according to the actual needs of selected ecological module, hydrology module and power module, built by different spatial and temporal scales coupled nested under the unified physical mechanism Eco - hydrological simulation platform. (2) technical support to eco-hydrological modeling platform, combined with the use of remote sensing and geographic information technologies, Shuangtaizihekou wetlands included in the basin-wide analysis, the establishment of a watershed basis of information database, the model input file formatting, the model runs and debugging, model validation. The relative error of the simulation results are controlled within 10%, correlation coefficient of 0.76 or more, Nash coefficient except for Baicheng East sub-station validation period was 0.57, and the remaining parity of 0.7, basically meet the requirements of simulation accuracy. (3) history restore simulation of long sequences from 1981 to 2005 eco-hydrological processes, analysis of wetlands Shuangtaizihekou eco-hydrological evolution characteristics, the results show that: the wetland ecological land area varied in the range of 7.83 to 9.25 million ha, of which degradation of wetlands from 1986 to 2000, an area of ??reduced human repair period, the area increased by 00,400 ha 14 200 ha in 2000 to 2005; 1981 to 2005 wetland catchment ecological hydrological elements (leaf area index, precipitation , the inter-annual changes in evapotranspiration, seepage, runoff depth and natural rate of replenishment of water) showed a decreasing trend, changes during the year showed a single peak curve; wetland catchment multi-year average natural rate of replenishment of water, 635 million m3 / a, which wet years 832 million m3 / a, the average year of 621 million m3 / a dry year to 470 million m3 / a. (4) based on the wetland catchment area eco-hydrological evolution characteristics, the positioning of regional ecological protection, to determine wetland ecological land constitute, considering the scale to meet the degree under different circumstances, propose suitable areas, the planning area as well as most cell ecological land area, respectively, to 9.25 Wan ha, 9.33 million ha and 77,200 ha; ecological water demand were 3.46 to 1,877 million m3 / a, 3.89 to 21.13 million m3 / a and 3.92 to 21.34 billion m3 / a. Wetland Ecological Water supply and demand analysis showed that: wet years the amount of water is sufficient to meet basic water demand for ecological; Pingshui years they can still meet most quarters of the minimum ecological water demand; ecological serious water shortage in dry years, ecological recharge 1.15 ~ 390 million m3 / a. Take appropriate ecological the replenishment control measures, the meet wetland ecological water demand.
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