中文摘要：

通过在野外试验地和室内模型上进行模拟降雨试验,研究粤北地区不同石漠化阶段的土壤退化特点和变化过程。结果表明：随着石漠化程度的加深,不同石漠化阶段的土壤理化性质差异显著,并与地上生物量和植被盖度呈相关性;当雨强大于60mm/h时,中度和重度石漠化土地的土壤地表侵蚀量呈现较大的波动性,产流后35min内重度石漠化样地的地表土壤侵蚀总量是轻度石漠化样地的7倍多;坡度和雨强对中度石漠化土地的土壤漏失量影响不大,体积越大的裂隙、漏斗产生的土壤漏失量反而越小;重度石漠化阶段是石漠化地区土壤退化过程中一个重要的转折阶段,在这个阶段中,形成多种水土流失的运移途径,土壤退化进入到一个突变的状态。

英文摘要：

The characteristics and changing process of soil degradation in different stages of rocky desertification of northern Guangdong were studied with simulated rainfall experiments in the experimental field and laboratory model. The results show that： The soil physical and chemical properties in different stages of rocky desertification had significant differences, and had correlation both with aboveground biomass and vegetation coverage. When the rainfall intensity exceeded 60 mm/h, there was a big fluctuation of the amount of soil erosion in moderately, severely rocky desertified lands. The amount of soil erosion in 30 minutes after the overland flow beginning in the severely rocky desertified land was over 7 times than that of the slightly rocky desertified land. Slope and rainfall intensity had little effect on sold leakage, and the amount of soil leakage was smaller in bigger volume of fracture or funnel. The severe stage of rock desertification was a very important turning point of sold degradation in different stages of rock desertification, in this stage, many migration paths of soil and water loss were formed, and soil degradation had catastrophe occurrences.