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Ecological drought causes shrinkage of wetlands area and severe destruction of ecological environment. As a result, the goal of this research is to provide practicable strategies and measures for relieving the ecological drought and solving the key problem of water resources guarantee, provide technical supports for the protection, restoration and development of wetlands ecological environment of Tianjin, guarantee water resources supply for wetlands, and keep the usual ecological function of wetlands as well.According to the wetlands protection and restoration program, master plan of Tianjin Municipality and the present situation of wetlands in Tianjin, in this paper, the study objects were mainly focused on the wetlands of Qilihai , Dahuangpu , Beidagang and Tuanbowa respectively. Firstly, calculated water demands of different wetlands in different seasons through the investigation and analysis of the four wetlands. Secondly, draw relation curves between water level, storage capacity and area of the four ecological drought areas, and calculated water level and area of each wetland under different ecological water demands based on the latest topography data and ARCGIS. And thirdly, defined the term of wetlands ecological drought through the analysis of meteorological & biological & artificial &comprehensive factors that impact ecological drought. Fourthly, determined both the identification indexes of ecological drought and water demand & seasonal distribution for wetland ecological system, classified ecological drought grades and calculated the quantities of replenishing water, based on the combination of ecology and water resources. Fifthly, determined the indexes which can be monitored easily and reflect the drought degree exactly, combined with the monitoring measures and time through theoretical analysis and calculation in order to arrange the monitoring station web appropriately and evaluate the degree of ecological drought rapidly. Sixthly, pursued the study on the capacity of water resources guarantee through the following nine aspects, water source, water quantity, guarantee rate, space-time distribution, rainfall, present discharge capacities of both first-class and second-class rivers, current engineering conditions, engineering measures of water diversion, and analyzed the utilization feasibility of local surface water source, diverted water and recycled water. And lastly, determined water resources allocation plan under different drought grades, and formulated the water transfer routes and necessary engineering measures in this regard.
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