By experiment, in this paper the differences of physiochemical and microbiological properties of soils between
Medicago sativa
land and traditional farmland (cotton field) are researched. The soil samples were sampled from a four-year
Medicago sativa land where fertilizers are not applied and a traditional farmland where cotton or wheat is grown and fertilizers are applied in Fifth Team of Hutubi Cattle Farm, Xinjiang. Some soil samples were sampled at soil depths of 0～10 cm,10～20 cm and 20～30 cm respectively in May 2004,which are used to measure the physiochemical properties of soils,and some others were sampled at soil depths of 0～10 cm and 10～20 cm respectively in June,which are used to measure the quantities of microorganisms in soils. The soil conditions in the Medicago sativa land and the traditional farmland are similar. The results show that contents of organic matter,total N,P and K as well as available N,P sand K in soil in four-year Medicago sativa land are all higher than that in the traditional farmland where fertilizers are applied every year.
Planting Medicago sativa can decrease soil bulk density,total salt and cl-,and can also increase total soil porosity. These reveal that planting Medicago sativa can effectively improve soils. The main purposes of this study are to reveal the effect of planting Medicago sativa on soil fertility and provide the scientific basis for extensively planting Medicago sativa in soil improvement in Xinjiang.