Zha Yong, Liu Yansui, Deng Xiangzheng
College of Geographic Science, Nanjing Normal University, Nanjing, 210097, China.
Environ Monit Assess. 2008 Mar;138(1-3):139-47. doi: 10.1007/s10661-007-9751-x. Epub 2007 May 11.
In this study we quantified land cover changes in the arid region of Yulin City, Northwest China between 1985 and 2000 using remote sensing and GIS in conjunction with landscape modeling. Land covers were mapped into 20 categories from multitemporal Landsat TM images. Five landscape indices were calculated from these maps at the land cover patches level. It was found that fallow land decreased by 125,148 ha while grassland and woodland increased by 107,975 and 17,157 ha, respectively. Landscape heterogeneity, dominance and fractal dimension changed little during the 15-year period while landscape became more fragmented, with an index rising from 0.56 to 0.58. The major factors responsible for these changes are identified as the change in the government policy on preserving the environment, continued growth in mining, and urbanization.
在本研究中，我们利用遥感和地理信息系统（GIS）并结合景观建模，对中国西北榆林市干旱地区1985年至2000年间的土地覆盖变化进行了量化。利用多时相陆地卫星专题制图仪（Landsat TM）影像将土地覆盖类型划分为20类。从这些地图上计算出土地覆盖斑块层面的五个景观指数。研究发现，休耕地减少了125,148公顷，而草地和林地分别增加了107,975公顷和17,157公顷。在这15年期间，景观异质性、优势度和分形维数变化不大，而景观变得更加破碎，指数从0.56升至0.58。造成这些变化的主要因素被确定为政府环境保护政策的变化、矿业的持续发展以及城市化进程。
