| As the most resources and environment problems we face are all due to landuse/cover change (LUCC ), LUCC becomes the focus of recent internationalresearch. Being the most seriously infected area by seawater intrusion in China, thedownstream of weihe river has a more complicated land use/cover change andlandscape ecological effects. The environment problems were caused by seawaterintrusion, such as degeneration of groundwater quality, soil salinization,deterioration of ecology and so on. Thus it makes great sense to research LUCC ofthis area. On the basis of summary of primary study, this article took land use/coverchange and its ecological effects as the major content. It's the first time to study onecological effects basis on landscape-ecology. The major content is an follows: 1. Based on 4 remote sensing images of this area in 1990, 1995, 2000 and 2004and other sufficient data, after phase of image estimation, digitalization, input ofattribute and statistical analysis, land use/cover change map and land use matrixwere made. This paper analyzed the temporal-spatial regulation of land use/coverchange during the 14 years followed by analysis of the corresponding relationshipsbetween the land use/cover change and landscape ecology. The result are as follows. 2.It appears that infield occupies the dominant position in this region, this alsoconforms to the research area's plain characteristic. Next is urban and culturalresidence. The grass land, the forest land and the water area occupy the area to besmall. The transferring from other use to urban and cultural residence was the mainform, which caused the grass, water and so on reduced gradually. The land-use change greatly with time. During 1990-1995, which is the time ofseawater intrusion developed greatly, and its also the time which human beings usedthe land irrationally, land use changed most distinct. After 1995, land use changesbecome weaker, as the same time, seawater intrusion went less serious. But the landexploration degree become stronger, it seemed that people were enlarging to the landdemand.The LUCC had little special difference. But the salty-water region and transitionregion were more changeable than limnetic region.3. Based on landscape ecology, landscape pattern is in changes unceasingly. â‘ The basic landscape pattern is infield which is piece distribution, it shows the plaincharacteristic in these area, and is patch number is very small. There are much morepeople in plain area, therefore there are many urban and cultural residence, the patchnumber is over 320, occupies the total patch number above 75%.â‘¡Compare thelandscape patch area rank, infield occupies the absolute superiority by the patchwhich area is more than 100 hm2, the grass tends to break up but the urban andcultural residence tends to concentrate. Other type changes unruly. â‘¢ Aftercalculation of landscape-pattern indexes ,we can conclude that the whole area in thisresearch time interval, its stability is dropping continuously.4. The landscape pattern change has a series of ecology effect.â‘ As the urbanand cultural residence occupied the infield, grass and water, its area increasinggradually, as it had negative effects on environment, so its caused seawater intrusion,water pollution and other environment problem. â‘¡The diversity and evenness of thewhole area are reducing, but these reduce is because of the urban and culturalresidence's rapid increasing, therefore the diversity and evenness reduce can not onlyindicate the landscape stability is increasing, but show its decreasing. â‘¢Patchbreaking up, reducing of its average area, could cause the interiorinhabit to lose, moreover the interior inhabit would easy to receive thedisturbance exterior. Thus it would reduce the species ability to resistance disaster.On the other hands, it could cause edge effects, which could hinder speciesmovement and the nutrient cycle, thus some certain species could die out, thediversity of this area would reduce.
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