广西岩溶地区农业生态系统的分析评价

广西岩溶面积较大，分布范围广。岩溶地区农业生态环境恶劣，土壤瘠薄，植被稀少，降雨分布不均，农用水源不足，加上农业生态系统内部结构失调，生态系统的特和能量入不敷出，资源开发利用不当，导致生态环境条件进一步恶化，生态平衡失调，自然灾害加重，农业生态系统的稳定性和持续性下降，严重地影响岩溶地区农业生产和国民经济的发展。必须因地制宜地调整农业生产结构，在资源开发利用上扬长避短，切合实际地发展林业和恢复植被

ANALYSIS AND EVALUATION OF THE AGRICULTURAL ECOSYSTEM IN KARST REGIONS OF GUANGXI

arst areas make up about 37. 8% of the total area of Guangxi, which are characterized by their deteriorated ecological environments with poor and thin soils, sparse vegetation, unevenly ditributed rainfall and short water resources. Meanwhile, the interior structure of agricultural ecosystem is unreasonable, the input of nutrition and energy is less than the output, and the irra.tional exploitation of natural resources results in further deteriorahon of ecological environmonts,the dislocation of ecological balance, the increase of natural dialers, and the decrease of the sta bility and continuity of agricultural ecosystem. Those have affected the development of agricultural production and national economy, and people's life and existance in Karst regions. It is neces sary to regulate reasonablly the structure of agricultural production, to develop forestry in line with local conditions, to enhance environmental protection and harnessing, to incrase the input of nutrition and energy in agricultUral ecosystem. The authors consider that the development of agriculture in the regions should presuppose the solution of food and clothing problems for the lo cal people and the coordination with market economy, and should follow the direction of eeo-agri culture and stereo-agriculture in order to achieve both long term and short term benefits.