中文摘要：

以阳山县江英镇为例，通过典型样地调查和取样分析，研究了粤北典型岩溶区石漠化过程中植被退化对土壤有机质及养分含量的影响。结果表明：（1）随着石漠化程度的加深，石灰岩植被的生境向旱生化和岩生化发展，植物群落结构越来越趋于简单。（2）石漠化过程与土壤养分状况有密切关系，随着土地石漠化的发展，土壤有机质、全N，以及碱解N、有效P、速效K含量呈现出显著下降趋势，土壤逐步贫瘠化。（3）土壤有机质和养分含量下降与植被退化形成正反馈关系，并具有退化方向的一致性和退化过程的同步性。

英文摘要：

Taking the Jiangying town in Yangshan County as an example, the effect of vegetation degradation on soil nutrient in rocky desertifieation process in typical karst area of Northern Guangdong was studied by typical samples plots investigation method. The results showed that ： （ 1 ） With the development of the rocky desertification, the territory of the limestone veg- etation was replaced by some more drought and more rocky species, the structure of vegetation community tend to be more and more simple. （2） There was a close relationship between rocky desertification process and soil nutrient condition, with the development of the rocky desertification, the nutrient contents of soil organic matte, total N, alkali-hydrolyzed N, a- vailable P and available K have showed a decreased obviously trend, the soil became more and more infertility. （3） The degradation of soil nutrient contents has a positive relation with vegetation degradation, and they have the consistency in the degradation direction and the synchronism in the degradation process.