城市交通绿地土壤抗蚀性——以内江市城区为例

Study on Soil Anti-erodibility of Urban Traffic Greenbelt——Taking Neijiang city as an example

选择内江市交通绿地（林地、灌丛、草地）为研究对象,通过对土壤干筛团聚含量、土壤机械组成、土壤水稳性指数（K值）、土壤抗蚀性指数S（％）等指标的测定和分析,研究了城市交通绿地土壤的抗蚀性能.结果表明,三种城市绿地土壤抗蚀性强弱不同,但都随时间的延长呈下降趋势,并且三种模式下土壤抗蚀指数都随浸水时间（t）呈三次函数曲线变化（R2＞0.9684）；其中相关分析得出水稳性指数与粘粒、物理性粘粒、＞0.25 mm粒径、2～5 mm粒径、5～7 mm粒径呈正相关关系,与粗粉粒、砂粒、0.25～0.5 mm粒径、0.5～1 mm粒径表现出负相关趋势,这说明土壤团聚体大粒径、机械组成粘粒和物理性粘粒含量越少,土壤水稳性指数越大,抗蚀性能越强.抗蚀性能强弱由大到小为：草地＞灌丛＞林地.

Soils of urban traffic greenbelt such as wooded land, shrubland, and meadow in the Neijiang city were taken as research subjects to examine the anti-erodibility of soil in the traffic greenbelt in the city by analysis of the indices like the dr- ying sieve aggregate, the mechanical composition, water stable index（the K value） and anti-corrosion resistance index. The re- sults show that the corrosion resistance strength the three kinds of soil differ in anti-erodibility,, yet all with a declining trend o- ver time. What＇s more, it is found that the soil anti-erosion indices under the three modes all take a changing trend in the curve of a cubic function with the soaking time. The correlation analysis shows that the water stable index and clay particle, physical clay, the granular sizes of 〉0.25mm, 2-5mm, 5-7mm are positively correlated with each other. Yet, a negative relation is found in between the water stable index and coarse silt, sand grain, the granular sizes of 0. 25-0. 5ram, 0.5-1mm, which indi- cates bigger the soil aggregates size, the less the contents of the clay particle, physical clay, and the bigger the water stable in dex is , a stronger soil anti-erodibility will be. The anti-erodibility in descending order is pure forest 〉 bush fallow 〉 meadow.