Technologically supported by RS and GIS, spatial analysis methods are applied to chart and research the dynamic changes of resource environment accurately and effectively.

In this article, all landuse data of 1986 and Landsat TM image of Yanyuan dated in 2000 are used. Based on the technology of GIS, we discuss the following points:

1. Making dynamic changing maps of forestland
Extraction and charting of forestl and information depends on processing enormous data derived from RS images effectively. Geographic Information System (GIS)has powerful abilities of storing, managing, analyzing, processing, and charting land-related spatial data. And it makes RS informationmore useful. Taking Yanyuan county as an example, the paper establishes a concrete exposition of making dynamic changing maps for the application of the soft wares of IMAGE
ANALYST, ARC INFO 7.1 and ARCVIEW 3.2. The attribute database of forestland in Yanyuan county is established automatically just as maps are compiled completely.

2.Analyzing the driving factors of forestland dynamic changes and offering some countermeasures
The analysis of the study shows that significant changes in the extent of forestland have occurred over the past 15 years (1986～2000). The total area of forestland tends to decrease, with 2 895hm2 forestland depleted. Meanwhile, the forestland structure have changed remarkably.

The area of the woodland was diminished to some extent. With the area of 782hm2 and 663hm2 disappeared, the shrub land and the sparse woodland were badly destroyed. On the other hand, the area of the other forestland boomed: in the year 2000, it covered 1 691hm2 and 3.4‰ of the total forestland area compared with the figures of 347hm2 and 0.7‰ in 1986. And the other forestland increased was almost relic forest and economic wood. As a result, cultivation and forest fire are pointed out to be the major causes for the changes. And we suggest that aimless and haphazard felling should be put to an end and fireproofing idea be enhanced. Furthermore, countermeasures are expected to be adopted to protect the present forestland and enlarge its coverage. The technologies of RS and GIS are found to be an efficient tool in monitoring resource environment. They become increasingly important for spatial analysis of forest resource and its sustainable development. Based on these methods, high quality maps are made rapidly; and the available multilevel information is provided for dynamic study scientifically.

Also they enable the user to manage resource data more effectively and enhance the decision-making process for planning purpose.