| Landscape spatial pattern is one of the central study fields in landscape ecology and in global change studies. The formation and variation of landscape pattern are the composite reflect of the area ecological environment quality, which are the results of multi-factor interaction of nature and man-made. And category, shape, quantity, area and spatial combination of landscape patch are the results of different disturbing factors, which in turn, affect the ecological processes of regions. Therefore, to study the certain landscape patterns provides an effective method for understanding the status of landscape ecology and its spatial variability. The main objectives of studying change of landscape patterns are to analyzing the ecosystem environment influence mechanism of natural evolution and human activities. That will help serving regional and even global sustainable development by revising human-self's actions, optimizing resource allocation, preventing worsen of ecology, strengthening the control of the planning.In the past 10 years, the society and economy have been changed tremendously in our country. And the landscape patterns have been determined by these changes. Owing to its unique advantages of zone-belt and resources, the zone around Changhuajiang river has been one of the accelerated growth areas of China's economy. So the change of land use around the upper reaches of the Changhuajiang river watershed is a typical representative of middle-mountainous district, Hainan province. Studies on landscape change features can help us find out the relationship of landscape structure, ecological process and human activity, which can also help us determine the intensity, way and the power of kinds of interferers to provide the important scientific foundation for the sustainable development of the zone.Taking the upper reaches of the Changhuajiang river watershed as the study zone in this dissertation, we studied the change state of landscape pattern and its reasons in a systematic way. There are five chapters in this dissertation. In chapter one, we review the concerned achievements and the late advances at home and abroad. Then we put forward a framework and research approaches based on the research features and trends on these subjects. In chapter two, we introduce the theories and methods about landscape pattern variation, in order to assist us in achieving this study. In chapter three, we survey the nature, society and economy in the study area. Then taking land use classification as the landscape ecological types of the study area, through processing the SPOT date of 1995 and 2005 with geometry calibration and the combination of computer classification and manual classification, and with the help of the current land utilization map, topographic map and field surveys in middle-mountainous district, the maps of landscape patterns are charted by means of remote sensing (RS), geographical information system (GIS) and global positioning system (GPS). In chapter four, the characters of landscape pattern change from 1995 to 2005 in the study area are studied by using FRAGSTATS calculation method, and the landscape pattern area change and structure change are analyzed in a systematic way. Finally, some suggestions are put forward for strengthening the landscape environmental management works. On the basis of the authors' studies, the results are as follows:(1) comparing the landscape pattern of 1995 with that of 2005,the PD of the landscape is decreasing, and the shape of patches is becoming more simple and formulary, with the distributing of patch types more dispersing and less connectivity.(2) comparing the landscape types of 1995 with that of 2005, we find out that:①the natural arbors are decreasing, with patches more fragmentation, size more odds, shapes more complex;②the area of natural shrubberies is increasing, with patches less fragmentation, shapes more simple and formulary ,the size of patches more even;③the area of natural grasses is increasing, with patches less fragmentation, shapes of patches more odds;④the area of timbers is increasing, with patches more dominance in landscape, more connectivity;⑤the area of Eucalyptus increases, with patches less fragmentation, shapes of patches more complex , more convergence, more connectivity;⑥the area of orchards is increasing, more connectivity;⑦the patches of the rubber is becoming more assemble, more connectivity, more formulary;⑧the area of plowland increases;⑨the area of reservoirs, rivers and ponds increases, with patches more assemble;⑩the area of cities decreases, with patches more dispersing, with shape more complexthe area of countries increases, with patches less connectivity, more dispersing, with shape more complex; the patches of the rest lands are more dispersing, with shape more complex;(3)In the process of economic development in the upper reaches of the Changhuajiang river watershed, a series of the ecological environment problems have appeared because a lot of landscape function broke off, and the connection of human landscape with natural landscape decreased, which aroused by the fragmentation of natural and semi-nature landscapes increased, the stability of the landscape structure decreased, as well as stress of human disturbance, resource and environment upon the landscape increased gradually. According to these, this study makes the changes of this zone's landscape pattern as its aim, which is also its pinpoint, and for those changes put forward its suggestions.
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