| This thesis studied on forest landscape spatial pattern and temporal dynamics based on RS .Cai Jiachuan,as the typical region of distribution of natural forests was the research object ,the TM images of 3 years of 1986,1997and 2004 as the main data sources,depended on the topographic map in proportion 1:50000 and supplemented by the data of forest management of 3 years of 1986,1997and 2004,remote sensing (RS) technology as the primary methods,supplemented by geographic information system (GIS) technology and the theories and methods of landscape ecology.Research achievements include the following elements :(1) Classification of forest landscape is based on data of multi-spectrum remote sensing of Landsat TM and terrestrial inventory .ERDAS images and ArcGIS are used as technical supporting systems for data processing .Supervised classification of remote-sensing image supported by terrestrial sampling plots and associated with inventory data of forest management are used in the study. As a result ,distribution maps of forest landscape of the study area of 3 years and they are will be used for the base data for further studying on forest landscape of study region.(2) With the support of ArcGIS,the areas of study region of 3 years are calculated .The result indicated,the areas of Chinese pine are more than 28 percent of 3 years,the following are hard latifoliate trees and soft latifoliate trees.Therefore,Woodland was mainly substrate of study area, and was dominant to control landscape structure, function and dynamic processes. The patches of wasteland,farm land,brushwood land and open forest land were in the form of mosaic.(3) With the support of ArcGIS,the slope,aspect and elevation were extracted and slice level was studied from DEM,then the distribution maps of forest landscape of the study area of 3 years were overlay with DEM .The result indicated:The study area belongs to the low mountain landscape types, most of the forest landscape types are distributed to 1 300 ~ 1 600 m. So the most appropriate range of the various species in the forestry centre is at an altitude of 1 300 ~ 1 600 m;The area of the various landscapes of three periods in the slope of 5°~ 15°and15°~ 25°is 70 percent of the total area during three periods respectively;The area of each landscape is almost the same in all slopes. AS a whole, the landscape area on the shade slopes and semi-shady slopes is larger.(4) It can be seen from Markov forecasts: when the interference to the landscape is the same of the 1997-2004 year,to 2014, the area of Chinese pine and hard broad-leaved forests in Caijiachuan Forestry Farm will increase gradually. The area of farmland, wasteland, thin woodland and soft broad-leaved forests will reduce to be the mixed coniferous and broad-leaved forest gradually. The successions of the community structure are in line with the biological characteristics and ecological characteristics in the region, and reflect the impact of the implementation of the Natural Forest Protection Project for the future development.(5) Through the analysis of the landscape heterogeneity of the dynamic changes ,we can find that the patch number of Landscape plaque increased at first and then went down ,and patch shape index of pine was slightly lower than Broad-leaved forest and soft wide-Lin from 1986 to 2004; the advantages of pine index during the three period were always in a dominant position. There was a increase in Landscape patch density from 1986 and 1997 and then it had a downward trend between 1997 and 2004.During the same peroid the largest Landscape with index was Chinese pine. Decrease of forest landscape shape index and Landscape advantage in the study area indicated that there was a fragmentation trend in forest landscape and Landscape plaque increasingly structured.
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