| As land is the basis for humanity survival, land use and land coverage change (LUCC ) becomes the focus of recent international research. Being the most seriously infected area by seawater intrusion in China, Laizhou Bay southern plain has a more complicated land use/cover change and driving mechanism. It is a typically ecological fragile region. Thus it makes great sense to research LUCC of this area.On the basis of summary of primary study, this article combines the seawater intrusion and land-use change, which is greatly significant for analyzing their mechanism, regulating the industrial structure and renovating the whole environment.(1) With sufficient data, after phase of image estimation, digitalization, input of attribute and statistical analysis, this article handles RS and GIS technology to obtain different-time analysis result, including land-use actual maps, its changing maps, transferring matrix, and many kinds of indexes. Thus we can understand the spatio-temporal rule of this area.(2) Under the influence of both natural and artificial factors, land-use structure has obvious changes. This can be embodied from follows.Firstly, land-use pattern changes greatly with time. During 1988-1995, which is the time of seawater intrusion developed greatly, land use changes most distinct. The area of infield, grass, water area and un-reclaimed land declined greatly. The degree of land use had a rise. The transferring from agricultural use to un-agricultural use was the main form, during which un-reclaimed land had the maximal changing range, while grass and un-reclaimed land had maximal velocity. From 1995 to 2000, the exploration degree becomes weaker, seawater intrusion goes to less serious. Land use changes become meeker, with less changing range. The area of infield, grass, water area and un-reclaimed land begin to rise.Secondly, LUCC has special difference. Limnetic region has bigger proportion of infield than in salty-water region and transition region, which relates with the distance to seacoast. And salty-water region is the hotspot during 1988-1995. It had a more exquisite change thananother two, with a larger synthetical dynamics degree. Un-reclaimed land was exploited to change to construct land. Inversely, the rise of water need and man-made importation of seawater accelerate intrusion of salty water. Meanwhile transition region has more distinct change in the period of 1995-2000 than others.Furthermore, after calculation of landscape-pattern indexes in transition region, we can conclude that the whole area has small diversity and evenness. Minority landscape types control the pattern. And most patches have regular configuration and serious fragmentation degree, which is most protrudent in 1995. The indexes of pattern have an accordant trend, becoming acute during 1988-1995 and meeker during 1995-2000, which is consistent with development of water intrusion.(3) With the help of Canonical correlation analysis, this article summarizes four main driving factors. They are salty water intrusion, population rising, industrial structure adjusting, industry development. Under study, we find that salty water intrusion has an obvious relativity with direction of land-use changes. The period of land-use changed most greatly is the time of salty water intruded rapidly. And the transition borderline is identical with the north boundary of irrigable land. Population rising, agricultural population proportion declining and industrial adjustment driven by economical benefit, boost the explosion of constructive land, engrossing large-area agricultural land.Since all kinds of factors have interaction, and form complex systemic structure, this article designs Systemic Dynamics Model to describe the mechanism of LUCC in study area, using the theory of Systemic Dynamics. On the basis of change of control variances, it sets three schemes to simulate the land-use changes. According as the second scheme, infield will arrive at dynamic balance. The overlay degree of plantation and utilization rate will improv...
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