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研究了云南南涧干热河谷退化山地人工恢复植被初期阶段（３～５年）主要植物群落的地上生物量和恢复植被后土壤水分及养分的相关动态。结果表明，几种外来植物的适应性强，早期生长迅速并能很快郁闭。人工群落生物量都高于当地次生的坡柳灌草丛。引进种的地上生物量和总平均生长量分别是坡柳的３～１６倍和５～２０倍，其生长速度也高于乡土树种云南松。雨季人工植被下土壤含水量比光坡地增加约１００％，表土层则增加 ２倍以上。但在旱季，林地土壤含水量与光坡地相近甚至低于光坡地。植被的恢复使土壤养分朝着良性循环转变。土壤有机质、速效钾含量提高，全氮含量稍有降低但不明显，速效磷含量降低，ｐＨ值有所下降。这些变化主要发生在土壤表层，人工植被及其土壤生态系统的恢复仍处于不稳定状态。
The aboveground biomass of main plant communities and the correlations between soil moisture and nutrients after vegetation restoration were studied in the initial stage (3-5 years) of artificial restoration of degraded mountainous areas in Nanjian dry and hot valley, Yunnan. The results showed that several exotic plant adaptability, early rapid growth and can quickly closed. Artificial community biomass is higher than the local secondary slope willow shrubs. The above-ground biomass and total average growth of introduced species were 3 ~ 16 times and 5 ~ 20 times than that of slope willow, respectively, and its growth rate was also higher than that of native species Yunnan Pinus. Under rainy season, the soil moisture content of artificial vegetation increased by about 100% compared with that of bare land, and that of topsoil increased more than two times. However, in dry season, the soil water content of woodland is similar to or even lower than that of light slope. The restoration of vegetation changes the soil nutrients in a virtuous circle. Soil organic matter, available potassium content increased, total nitrogen content decreased slightly but not obvious, available phosphorus content decreased, pH value decreased. These changes occurred mainly in the soil surface, artificial vegetation and soil ecosystem recovery is still in an unstable state.