黄土高原土地利用动态变化及其生态效应

以黄土高原为研究对象，在遥感和GIS技术支持下，分析区域1986-1997年土地利用时空变化，并运用马尔可夫模型对未来土地利用进行预测，采用生态弹性度进行土地利用变化与生态效应研究。结果表明：黄土高原土地利用动态变化显著，相对变化量远远大于绝对变化量；土地利用类型转换非常剧烈，区域1986-1997年修正土地利用动态指数的变化趋势是高覆盖草地〉建设用地〉其他林地〉灌木林地〉水田〉水体〉未利用土地〉有林地〉旱地〉其他草地；土地利用的年均动态变化指数为2．17％，旱地、灌木林地、高覆盖草地、水体、建设用地和未利用土地垂直重心指数上升，水田、其他草地垂直重心指数下降；1986、1997、2008和2019年早地、有林地和其他草地面积一直在微弱减少，水田、高覆盖草地、水域、建设用地、未利用土地在缓慢持续增加，灌木林地和其他林地出现了先增加后少量减少的趋势；1986、1997、2008和2019年生态弹性度分别为5．17、7．30、7．60和7．65，区域生态弹性度整体呈现上升趋势，但上升幅度呈减小趋势。

Dynamic change of land use and its ecological effects on the Loess Plateau

Based on RS,GIS and related data,the paper analyzed the land use change on the Loess Plateau between 1986 and 1997.With the Markov Model,the land use change in the future was forecasted,and the relation between land use and ecological effect by ecological response limit was studied.Results showed that the land use dynamic change on the Loess Plateau is remarkable,the relative value of which is larger than the absolute value,and land use has changed obviously between land use types.The descending order of land use change rate is grass with high coverage,construction land,other forest land,shrub land,irrigated land, water body,waste land,wood land,rainfed land and other grass land.Land use dynmic change index is 2.17%,from vertical c.g.index change,status of other grass land and irrigated land is improving,stock raising is suitablerice,food need drives the ascend of vertical c.g.index of rainfed and irrigated land and forest land.land use dynmic change index of irrigated land and other grass land is decline,and others is raise;ecological response limit is 5.17,7.30,7.60 and 7.65 in 1986,1997,2008 and 2019,ecological response limit is uptrend,but range is decrescent.