土地退化是一个世界性的环境问题，中国是世界上土地退化最严重的国家之一，松嫩平原是一个正处于退化发展过程中的典型地区。目前，松嫩平原大约有22%的土地发生了不同程度的退化，也称荒漠化。至今还没有大面积治理退化土地的有效方法。通过对种植黄花草木樨样地的监测，根据土壤物理化学性质的变化分析了防治退化土壤的效果。结果表明，在种植黄花草木樨后，土壤中的有机质、水解性氮、全氮含量都明显增加。土壤脱盐率较高，土壤中盐分含量、pH值和碱化度明显降低。土壤中硒和钼含量普遍减少。黄花草木樨还可有效地改善土壤的通透性能，土壤容重变小，孔隙度增大。土壤的含水量及田间持水量提高，保水持水能力增强。种植黄花草木樨斯列金1号可提高土壤肥力，改善土壤物理性状，防止或减缓水土流失，而且还可提供丰富的优质牧草，其种籽有重要的经济开发价值。

Soil degradation is a worldwide environment problem, and China is one of the countries with most serious soil degradation problem. The Songnen Plain is a typical area in degenerating, where degradation of different degrees, i.e., desertification, has so far taken place in around 22 percent areas. At present there is no effective method to improve the degenerated soil in such an inmense area. Therefore, Melilotus officinalis Sligen 1 has been introduced from Russia, and the experiments on planting, reproducing, soil improvement, etc. are being conducted all successfully. This article studies the effects of planting Melilotus offcinalia on improving the degraded soil through the analysis of the physical and chemical properties of soil. The results show that planting Melilotus offcinalia can increase organic matter, total N, and hydrolytic N. After planting Melilotus offcinalia, the desalinization rate is very high and total salt content, pH and exchangeable sodium percentage in soil all decrease. In addition, after planting Melilotus offcinalia, selenium and molybdenum in soil present a downward trend. The planting of Melilotus offcinalia can effectively improve the ventilation of soil, and the soil bulk density decreases while total porosity of soil increases. Water content and field capacity both increase, showing that the water-holding capacity increases. In a word, to plant Melilotus officinalis Sligen 1 could enhance the fertility, improve the physical properties, prevent or decrease the loss of water and soil, and offer abundant high quality pastures whose seeds are valuable for economy exploitation.