黄土丘陵沟壑区退耕地土壤养分因子对植被恢复的贡献

为了探求各土壤养分因子对植被恢复贡献的大小．利用因子分析(Factor analysis)对黄土高原丘陵沟壑区退耕地植被恢复中的土壤养分进行了多元统计分析，定量研究了土壤养分环境对植被恢复的作用。结果表明：住所选取的6个土壤养分因子中，土壤有机质、有效N、全P和速效P对植被恢复的贡献较大．是限制该地区植被恢复的主导因素，其它养分因子的贡献相对较小。根据土壤养分因子间的相关系数，土壤有机质与全N和有效N呈显著相关。因此，在评价土壤养分因子对植被恢复贡献大小时．选取土壤有机质、氮和磷的含量作为评价指标，不但节省了时间和财力，而且有助于植被恢复的快速评价。

Contribution of Soil Nutrient in Abandoned Lands to Vegetation Restoration in Hilly and Gully Regions on the Loess Plateau

The paper aims to explore the contribution of soil nutrients to vegetation restoration.According to factor analysis of soil nutrients during vegetation restoration in abandoned lands in hilly and gully regions of the Loess Plateau,the effect of the soil nutrient was studied. The result showed that the contributions of soil organic matter,available N,total P and readily available P to vegetation restoration are relatively bigger in the six soil nutrient factors chosen,these factors were dominant on vegetation restoration in this region,and the contribution of others were not evident. The correlation between soil organic matter and total N and available N was significant according to the correlation of soil nutrients. Soil organic matter,nitrogen and phosphorus were regarded as the index in evaluating vegetation restoration.This not only save time and money,but also helped to rapid evaluation.