LI Yuefen;GONG Heyang;LIN Nianfeng;LASOUKANH Viengsouk;ZHAO Yiying
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.
