| With mostly alluvial and marine type coastal plain in Tianjin, the changes of the ancient coastal left a series of ancient coastal lagoons to the plain area, so there are many types and large area wetlands in Tianjin. Meanwhile Tianjin is a stopover and transfer station for East Asia-Australia migratory birds in the migratory route, an important "Inn" for north-south migratory birds in eastern Asia, is also a rare waterfowl habitat with international significance. With the rapid economic development in Tianjin, Tianjin wetland ecological environment has been undergoing significant changes. Therefore, this paper takes Tianjin as study area. Three phrases of ETM/TM remote sensing images of 1999,2003 and 2007 are used to do wetlands information extraction and classification by using the technologies of remote sensing and geographical information system. Land-use transfer matrix has been introduced to obtain 8 years land use changes in the study area; from the perspective of landscape ecology using landscape indices to analyze the change of wetland landscape pattern in different periods. On this basis, according to landscape pattern optimization theory, with the minimum cumulative resistance model (MCR), the research has studied 6 single factor landscape ecological security pattern of the topography (elevation, slope), the different landscape types, the vegetation cover information,and human disturbance in Tianjin.The research has obtained Tianjin wetlands integrated ecological security pattern by weighted overlay, divided ecological security regions with different security level and then built the ecological source, ecological corridors, and ecological step stones to enhance the space link of the ecological landscape. At last, compare and analyze the ecological land planning of the integrated landscape ecological security pattern with different security levels, propose wetland management and protection strategies. The following conclusions:(1) According to the basic data of land use, the land use change process and characteristics in Tianjin since the 1999-2007 is quantified by the land use transfer matrix and landscape indices and other methods, the results show that,â‘ the substantial expansion of urban Fringe, and the development and construction of economic development zones,Dagang industrial zones and the new coastal region is diverted through a lot of agricultural land, natural and artificial wetlands to achieve,â‘¡the study period, the regional distribution of various types of landscape elements tend to be the scattered and fragmented hybrid alignment, the control effect of the regional dominant landscape type to the landscape pattern is weakened. Landscape heterogeneity at the same time has a gradual increased, and the contribution of different landscape types to landscape diversity has decreased.(2) With a minimum cumulative resistance model (MCR), the research has established the altitude, slope, land use, vegetation cover, human disturbance 6 single factor landscape ecological security pattern and obtained integrated landscape ecological security patterns through the weighted overlay 6 single factor landscape ecological security pattern. The paper uses the half variance interval classification of mathematics statistics method to classify the resistance of the minimum cumulative resistance surface. Accordingly, the analysis the minimum cumulative resistance threshold which confirmed the landscape security pattern, and divided ecological security region with different security level. Then determine the optimal composition of ecological security pattern, obtained the spatial distribution of ecological corridors and step stones. The research makes a comprehensive ecological land use plan for wetland landscape and proposes protection measures for wetland landscape pattern optimization in Tianjin, through statistic the land area and proportion of various landscape types under different security level of the integrated landscape ecological security pattern in study area.
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