Many ecological methods are available in micro-scale studies, however, the studies in Loess Plateau use landscape scale. Quantitative ecological method is a group technique of multivariate analyses and becomes more and more important in vegetation studies. Geographical Information System(GIS) can not only store and manage spatial data, but also provide easy ways of spatial analyses, which may meet the demands of ecological researches in landscape scale with a lot of spatial data. A new technique combining G...