庐山风景名胜区景观格局动态及其模拟

The landscape pattern changes and simulation in Lushan Mountain national Park

在遥感和GIS技术支持下,以1988和2000年的TM影像为主要数据源,采用景观格局指数方法分析了庐山风景名胜区的景观空间格局特征和变化情况。结果表明,庐山的景观格局在过去的12a内发生了较大的变化,阔叶林由1988年的25.88%上升到2000年的54.51%,年均增加782.43hm2,总增加面积与针叶林、灌草地和耕地的总减少面积相当。针叶林、灌草地、建设用地和未利用地的斑块数量和斑块密度呈现出快速增长的趋势,其中以灌草地年均增加123.42块为最高;与此相反的是水体、阔叶林和耕地的衰减,其中耕地以年减少约246.42块的减速最为迅速。针叶林和灌草地的破碎化进一步加强,而阔叶林则填补了前两者减少面积的空白。1988年灌草地的最大斑块指数列居各景观类型之首,12a后这一优势为阔叶林景观所取代。建设用地总体变化幅度不大,但已经呈现出明显的扩散化趋势。两期的灌草地的景观形状指数和分维度位居各类型景观之首,表明受外来干扰强度最小;耕地的复杂性变化最快,形状指数和分维度分别下降了44.5744和0.0726。庐山的香农多样性和香农均匀度随时间的迁移而有所下降,分别下降了0.2394和0.1231,同期景观破碎化指数上升了0.1633。基于马尔柯夫模型的景观格局模拟值与实测值大致相当,结果表明目前景区的景观生态安全格局面临严重危机。导致庐山景观格局动态变化的驱动力主要来自于城市化的快速推进、旅游业的快速发展和政策的调控作用。

Lushan mountain national park is the key researched object that the pattern and change can reflect the ecological process of man-land relationship. In this paper, landscape metrics combined with gradient analysis is employed to analyze the landscape pattern changes of Lushan Mountain, based on the TM images of 1988 and 2000, respectively. The results demonstrate that the landscape pattern of Lushan mountain changed dramatically in 12 years, the increased area of broadleaved forest, which added 782.43 hm^2 average from 1988 to 2000, were equivalent to the decreasing area of coniferous forests, shrubbery and meadow, and farmland. The NP and PD of coniferous forests, shrubbery and meadow, build-up area and unused land, taked on the swift growth, in which the NP of shrubbery and meadow increased 123.42 pieces per year; in contrast, the water, broad-leaved forest and farmland decreased, in which the farmland lose 246.42 pieces every year. Broad-leaved forest supplied the fragmentation area of coniferous forests, shrubbery and meadow. The LPI of shrubbery and meadow ranked on the first in 1988, whereafter, the advantage was replaced by broad-leaved forest. Although build-up area changed in a limited extent, we should pay attention to the diffuse trend. The LSI and FRACT of shrubbery and meadow in two periods are situated head of the various types of landscape, which indicated that they had been interfered externally least; The farmland＇s complexity changed most rapidly, the LSI and FRACT decreased 44. 5744 and 0. 0726 respectively. The SHDI and SHEI dropped along with the time, decreased 0. 2394 and 0. 1231 respectively, at the same time, the fragmentation index increased 0. 1633. Simulated value approximately equal to actual value that based on the Markov model of landscape prediction, it shows that landscape ecological security pattern was faced with serious crisis, while the actuating force are mainly from speeded-up urbanization, speeded-up tourism and policy control.