甘肃河西地区蔬菜温室与粮田土壤主要养分（碳、氮、磷、钾）储量比较

Select three kinds of land use patterns in the Gaotai County in Hexi region of Gansu Province ，vegetable-vegetable rotation greenhouse, corn- vegetable rotation greenhouse and grain, determination of main nutrient content in 0~100 cm soil ，organic matter, total nitrogen, nitrate nitrogen, available phosphorus, available potassium and its distribution. The results show that, in greenhouse soil nitrogen, phosphorus, potassium and carbon reserves are large, the reserves of nitrate nitrogen and the phosphorus are higher. Nitrate nitrogen of vegetables - vegetable rotation greenhouse soil cumulative total to 1368 kg/hm2, total phosphorus reserves reached 15115 kg/hm2, they are 14.37 and 1.46 times of grain soil respectively,. The EC value of soil vegetable-vegetable rotation greenhouse is higher than grain soil, while pH of vegetable-vegetable rotation greenhouse soil is decreased than grain soil, which shows vegetable greenhouse appear salinization and slight acidification. While the vegetable - vegetable rotation greenhouse soil nutrients especially organic matter and nitrate nitrogen, the existence of a large number of not only at the surface, in the deep soil content is higher, While the vegetable - vegetable rotation greenhouse soil nutrients especially and organic matter, nitrate nitrogen, the existence of a large number of not only at the surface, in the deep soil content is higher.Greenhouse in 20~100 cm soil nitrate nitrogen reserves accounted for 74.3% accounted for 100 cm soil layer, the organic matter ratio reached 69%, that visible There is a serious phenomenon of greenhouse nutrient leaching. A variety of nutrients of corn- vegetable greenhouse are lower than vegetable-vegetable greenhouse, that rotation of vegetable and grain crops such as corn, can slow down the vegetable greenhouse nutrients accumulation, not only improve the utilization rate of fertilizer, but also reduce the pollution to the environment. Therefore, the greenhouse vegetable soil management should control the application amount of N and P fertilizer, reasonable rotation with crops and proper lime soil acidity adjustment, pay attention to irrigation method. Add lime reasonably to adjust the acidity of soil and pay attention to irrigation method.)