两种不同生态区坡改梯对土壤氮磷含量影响的研究

分别在干热河谷生态区和华西雨屏生态区的坡改梯地区设置试验小区和对照试验区，通过采集土壤样品进行室内分析，研究在不同的坡位、不同的季节变化下两种生态区实施坡改梯措施对土壤养分保持的效果。干热河谷生态区以清溪小流域为例，华西雨屏生态区以凤鸣小流域为例。试验结果表明，在两个生态区的坡改梯工程试验区，空间上，各个坡位氮磷养分的含量均高于对照区，并且养分含量的极差小于对照区，即实验组的养分流失小于对照组;时间上，夏季较冬季土壤养分流失更严重。文章从流域尺度探索坡改梯对氮磷养分流失的影响规律，以期为流域面源污染的防控提供一些指导，也可为坡改梯效果评价体系的完善提供一些参考。

Effects of Slope-changed Terraces on the Soil Nitrogen and Phosphorus Contents in Two Different Ecological Regions

In this study,the area of slope-changed terraces in two ecological zones,includingthe dry-hot valley and the Huaxi Yuping,were selected as test group and control group,respectively.Soil samples were collected and analyzed to study the effect of slope-to-terrace measures on soil nutrient conservation in two ecological areas under different slope positions and different seasons.Qingxi small watershed was taken as an example in dry-hot valley ecological zone,and Fengming small watershed was taken as an example in the Huaxi Raining Zone.The results showed that the contents of nitrogen and phosphorus in the test group is higher than that in the control group.Moreover,the range of nitrogen and phosphorus contents in the test area is significantly lower than that in the control area,meaning that the nutrient loss of the test area is less than that of the control area.The results also found that the soil nutrient loss is more serious in summer than in winter.This paper reveals the influence of slope-changed terraces on the loss of nitrogen and phosphorus at the watershed scale.Therefore,our results can not only provide some guidance for the prevention and control of pollution originated from the watershed,but also provide some reference for further improving on the evaluation system of the slope-changed terraces.