应用生物技术改良退化土壤的效果——以黄花草木樨改良盐碱化土壤为例

通过对种植黄花草木樨样地的监测，根据土壤理化性质的变化分析了退化土壤的改良效果。结果表明，种植黄花草木樨后，土壤脱盐率较高，土壤中盐分含量、pH值、交换性钠和碱化度明显降低，有机质含量显著增加。黄花草木樨还可有效地改善土壤的通透性能，使土壤中小于0．001mm和0．001～0．005mm的粘粒减少，0．05～0．25mm的砂粒增加，土壤体积质量变小，孔隙度增大。这一生物技术具有改善土壤结构、增加土壤肥力的特点。黄花草木樨是干旱半干旱地区改良退化土壤的一种优良牧草。

Effects of biotechnology on improving the degraded soil——An example of planting Melilotus offcinalia for improving saline-alkaline soil

This article has studied the effects of planting Melilotus offcinalia on improving the degraded soil through the analysis of physical and chemical properties of soil. The results showed that the desalinization rate is very high and total salt content, pH and the mass fraction of exchangeable sodium in soil decreased after planting Melilotus offcinalia. But the content of organic matter has increased. The planting of Melilotus offcinalia significantly increased the amount of macro granular aggregate and the porosity of the soil, but decreased the amount of micro granular aggregate and the bulk density of the soil. This biotechnology had a characteristic of improving the structure and enhancing the fertility of the soil. So it is suggested that Melilotus offcinalia should be a kind of excellent pasturage for improving the degraded soil in arid and semiarid regions.