| There were large areas of salinizd soils in the west of Jilin Province, and the ecologicalenvironment of this area was vulnerable due to the special climate and geographicalenvironment. The constructed wetlands of this program were located at the neighbouring areasof the Momoge Nature Reserve, where the arid climate, lack of precipitation and surfacerun-off supply had led to deterioration of the wetland ecosystems. It was proposed that theoil-field waste water from the Yingtai oil-production factory was reused for the restoration andestablishment of surface flow wetland. The ecological environment of the constructed wetlandarea was primarily improved. Meanwhile, the vegetation coverage and the birds increasedobviously, and the benefit of environment, society, and economic were improved.The salinity and chloridion (Cl~-) concentration of the oil-field waste water were both athigh level. Hence, Cl~-was selected as an indicator of soil secondary salinization to investigateof the transmission and fate of inorganic salt ions during the irrigation process in theconstructed wetlands, and to provide a scientific basis for constructed wetland establishment.The results may provide a scientific guidance for the wastewater comprehensive utilizationand regional ecological restoration.In present study, the transmission and fate of Cl~-in the irrigating process of constructedwetlands was studied, and a scientific basis was provided for constructed wetlandestablishment. Otherwise, water resource balance between the amount of water supply andecological water requirements (lake, soil, plant, and wildlife) of wetland region, at semi-aridand arid areas, irrigated by oil-field wastewater were investigated. Based on3S (RS, GIS, andGPS) technology, the partition and dynamics of land use types in2001,2006,2008, and2010had been analyzed. An index system was established for assessing the health status ofconstructed wetland ecosystems. Meanwhile, a comprehensive ecological assessment indexsystem was established concerning ecological environment, economic, and society. Thequantitative evaluations of the ecosystem health and comprehensive ecological benefits wereanalyzed by means of square difference method.First, the engineering situation, scale, balance between salt and water, the problems, andthe operation effects were all analyzed. Second, the Yingtai oil production factory-constructedwetland in the west of Jilin Province was selected as the research area, and the Cl~-in oil-field waste water after secondary treatment was the research object. An interval dynamicmultimedia equivalence (IDME) model was developed to simulate the dynamic environmentalbehaviors of Cl~-in six bulk compartments: air, water, soil1, soil2, flora, and groundwater thatthe soils in the constructed wetlands were distinguished into soil1(soil without water covering)and soil2(soil with water covering). The vetification results indicated that both of the intervalsteady multimedia equivalence (ISME) and IDME model can be applied for the simulationof the transmission and fate of Cl~-in multimedia environments. The result showed the two soilcompartments were the dominant sinks of Cl~-, and the mass transmission was finished betweenthe components of soil and groundwater. The comparison study of simulation results andenvironmental background value suggested the Cl~-concentration in oil-field waste water, soil1, soil2, plant, and underground water were1.41%,5.57%,3.53%,1.82%,1.50%,respectively. Meanwhile, the dynamic simulation results showed that there was no significantincrease in the level of Cl~-during the wastewater irrigation, which indicates that the oil-fieldwastewater reused in the irrigation of the constructed wetland could contribute to the regionalecological restoration.The water resource balance between the amount of water supply and ecological waterrequirements (lake, soil, plant, and wildlife) in wetlands region, at semi-arid and arid areas, inyears of2001-2010irrigated by oil-field water were investigated. Based on3S technology, thepartition and dynamics of land use types in2001,2006,2008, and2010had been explored.The results indicated that the total ecological water requirement of2003-2010ranges during1.62-2.24×106m3per year, and the supply amount of oil-field in the region was2.12-2.84×106m3per year. The irrigation amount of oil-field can meet the basic ecologicalwater requirement of these wetlands. Meanwhile, in2010the area of water body and paddyfield increased by2.3and10times than the year of2001, and the area of forest and marshincreased by40.15%and29.5%, respectively. It can be found that water shortage andecological environment in arid and semi-arid areas had been improved by oil-field waterirrigation.In addition, a comprehensive ecological assessment index system was establishedconsidering ecological environment, economic, and society. The quantitative evaluation of theecosystem health and comprehensive ecological benefits were studied by means of square difference method. After running eight years, the levels of the ecosystem health andcomprehensive ecological benefits of constructed wetlands both changed from level IV tolevel II. And the development of economic, ecology and society improved.The research results suggested that the establishment of the Yingtai oil-productionfactory-constructed wetland and oil-field wastewater reuse for constructed wetlands hadsolved the problems of ineffective inrejection of oil-field wastewater. And the the oil-fieldwastewater reused in the irrigation of the constructed wetlands contributed to the regionalecological restoration.
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