| In this paper, by analysis on four temporal TM/ETM remote sensing images in 1993, 2001, 2003 and 2006, defined as 3 phases, 1993-2001, 2001-2003, 2003-2006, with the assistance of the field investigation and historical data, the landscape status of mangrove wetland at Luoyang Jiangkou and its surrounding areas, located at Fujian Province, were analyzed. Moreover, the landscape pattern changes and their driving factors were studied, and the impacts of mangrove wetland landscape pattern changes over there on the local entironment were evaluated. The results are shown as following:(1) Mangrove are mainly distributed along the east coast of Luoyang Jiang River, belonging to Huian County, which were directly influenced by the execution of mangrove wetland restoration since 2002 in Hui'an County.Spartina grassland were concentrated along the west side of the Luoyang Jiang River, belonging to Luojiang district and Fengze district .(2) The local landscape varied significantly in the period from 1993 to 2006. The landscape types within the research area included such seven categories as mangroves, Spartina grassland, bottomland, water, built-up and transportation land, other forest and farmland. The areas of building and transportation areas increased rapidly, the areas of Spartina grassland increased to a certain extent, however the coverages of forest and farmland decreased fast. The areas of landscape components changed relatively quickly around 2001. Due to urban and rural constructions and controlled invasive alien species, dynamic degrees of Spartina grassland, farmland and building and transportation land reached their peaks in the period from 2001 to 2003. Dynamic degrees of bottomland and other forest reached their peaks during the last period. During whole period, for the land cover change among the local landscape components, building and transportation land increased 1526.17hm2 , which mainly transferred from forest (819.44 hm2), farmland(418.35hm2), water and bottomland.(3) During the second period, as a result of the human irrational activities, mangrove landscape spatial pattern in the region had tended to become fragmented, patch-distributing.. Based on the analyses of other six landscape types, continuity and integrity of Luoyang Jiangkou mangrove wetland was worst, which can be attributed to the city construction and the development of economy.(4) Compared to the total area of 1993, mangrove area had increased up to nearly 5 times, 145.08hm2 by 2006. The dynamic degree of mangrove was the highest, up to 189.47% during 2001-2003, related to the conservation, plantation, restoration for the mangrove wetlands. The scope of mangrove areas had begun to extend constantly to northwest during the first period, however the distribution centroid of mangroves had changed to southeast in the second and third periods.(5) In the second period, mean patch area (0.34hm2) of mangrove in our study region was smallest,but patch number (58), degree of fragmentation (0.000 291), degree of separation (223.15), patch shape index (20.67) and fractal dimension (1.50) reached the maximum values. It means that, during that time, mangrove landscape spatial pattern in this region had tended to become fragmented, patchy and shape were most complicated due to human disturbance.(6) According to the effects of dynamic change of the local mangrove wetland on ecological environment, it was revealed that the different vegetation types had extremely significant impact on the population density of fiddler crabs. There were significant differences between Light Aegiceras Beach and mature trees, candel, Avicennia marina, wherease not so much difference were found among amid Aegiceras tree, candel, Avicennia marina. The result from two-factor variation analysis of the impact of different mangrove species and age on the fiddler crabs population density showed that: the interaction of species, age, species and age had extremely significant impact on the population density of fiddler crabs. The result of two-factor ANOVA of the impact of different mangrove species and canopy density on the fiddler crabs population density showed that, tree species and canopy density respectively had extremely significant impact on the population density of fiddler crabs, however, the interaction between tree species and canopy density had no obvious impact on population density.(7) According to the analytic results of the landscape variation of Fujian Luoyang Jiangkou mangrove wetland, the regulation and control countermeasures were proposed for Fujian Luoyang Jiangkou mangrove wetlands.
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