关键词: 喀斯特地区, 退耕还林还草, 自然恢复, 人工造林, 生态环境

Abstract: In light of the problems of aggravated soil erosion and litho-desertification of the karst regions in Northwest Guangxi as a result of degradation of forest ecosystems,six “grain-for-green” models(five models of artificial afforestation or grass planting,and one model of desertation for natural vegetation restoration)were screened out for quick restoration of vegetations in the regions and evaluated for their respective ecological effect.Results show that with the years passing by,soil fertility and biological productivity of the fields under the six models of management were increased significantly.In terms of soil erosion control,the six models were in the order of desertation for natural restoration>pasture>chestnut plus honeysuckle>bamboo>cajan>common zenia,whereas in terms of the economic benefit,the order would be pasture>common zenia>bamboo>chestnut plus honeysuckle>cajan>desertation.

Key words: karst regions, grain-for-green, natural restoration, artificial afforestation, eco-environment