Abstract: The evaluation of ecological importance is an effective way to identify the important ecological function areas and to optimize the regional spatial development pattern. In this paper, a model for evaluating the ecological importance by integrating the suitability of ecological factors and the importance of ecological locations was proposed, and, taking the Xijiang River Economic Belt of Guangxi as a case, the spatial zoning of ecological importance and its spatial overlay relationships with the distributions of current construction lands were studied. In the Belt, the zones with extremely important, very important, important, general, and unimportant ecological importance accounted for 16%, 36%, 17%, 15% and 16% of the whole area, respectively. The western part of the Belt had a relatively high importance, followed by the eastern part, while the central part had the least one. The existed construction lands in cities and towns and the rural lands were mainly located at unimportant, important, and very important zones, whereas the industrial and mining lands were in relatively dispersed distribution. To a certain extent, a selective and oriented ecological spatial occupation based on the evaluation of ecological importance could alleviate the ecoenvironmental pressure induced by regional industrialization and urbanization, and thus, realize regional sustainable development.

Key words: shrub ecosystem, rocky desertification, plant nutrient, soil nutrient.