With GIS and RS techniques,the Landsat TM data of three time-series (in 1987,2000 and 2010),combined with the thematic maps and the ground survey data in 2011,were hierarchically extracted to identity mangrove forests and other land use and cover patterns around Qinglangang Bay.Together with the local expert knowledge,totally 7 land use categories,such as forestland,farmland,construction area,water area,unused area,aquiculture pond and mangrove forests,were extracted.The trajectory of mangrove forest change and the transfer matrix of the land use were analyzed to retrieve the temporal and spatial features of the forest change and the driving force.The results showed that area of mangrove forests decreased by 37％ during 1987-2010,and the decreased area was mainly distributed along the mouth of the river.The annual rate of reduction during 1987-2000 and 2000-2010 was 39.4 and 17.6 hm2 · a-1,respectively,and the corresponding annual rate of change was-2.5％ and-1.4％.Development of aquiculture in the previous mangrove forests during 1987-2000 was the main reason for mangrove deforestation.The forest regeneration was found mostly within of the mangrove forests except for the entrance of Wenchang River where the mangrove forest developed toward the sea,probably due to insufficient power of colonization to seaside.The LUCC analysis indicated that forests,construction land and aquicuhure pond in the surrounding of the mangrove forests increased markedly,the farmland decreased continually,and the water area including river and pond was stable during 1987-2000.The urbanization and the development of tourism drove expansion of construction area,and the policy of restoring forests from previous farm land promoted an increase in forest cover since 2000.
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