沙湾县膜下滴灌棉田土壤盐分和养分垂直分布特征

Vertical Distribution Characteristics of Soil Salt and Nutrients in Drip Irrigation Cotton Field under Plastic Film in Shawan County

为了掌握膜下滴灌棉田土壤盐分和养分在土壤剖面的分布特征,2016年9月在北疆棉区沙湾县采集98块条田0~100cm土壤样品,分析了膜下滴灌棉田土壤盐分和养分含量的垂直特征。结果表明,沙湾县膜下滴灌棉田表层(0~20cm)土壤pH值平均值为8.6,盐分均值达到2.53g/kg,但调查样点中仍有近1/3的条田为盐化土壤;土壤有机质、全氮、碱解氮含量分别为14.92g/kg、0.86g/kg、54.3mg/kg,处于低级水平;土壤有效磷、速效钾含量分别为21.6mg/kg、231mg/kg,处于较高水平。沙湾县土壤pH值、盐分含量在0~100cm土层自上而下存在明显的递增趋势,且在80~100cm土层产生盐分积聚现象;土壤有机质、全氮和速效养分自上而下存在明显的递减趋势,但有机质、全氮和碱解氮在0~20cm土层较高,有效磷和速效钾在0~40cm有积聚现象。

In order to master the distribution characteristics of soil salt and nutrients in soil profile of drip irrigation cotton field under plastic film,98 soil samples were collected from Shawan County,Northern Xinjiang in September 2016,and the vertical characteristics of soil salt and nutrient content in drip irrigation cotton field under plastic film were analyzed.The results showed that: The average soil pH of the surface soil (0-20 cm) of the drip irrigation cotton field was 8.6,the average salt content was 2.53 g/kg,and nearly 1/3 of the stripe field were salinized soils in the survey.Soil organic matter,total nitrogen and alkaline nitrogen were 14.92 g/kg,0.86 g/kg,and 54.3 mg/kg,respectively,which were in the low level.Soil available phosphorus and available potassium were 21.6 mg/kg and 231 mg/kg,respectively,which were in the high level.Soil pH and salt content increased from top to bottom in the 0-100 cm soil layer,and salt accumulation occurred in the 80-100 cm soil layer;soil organic matter,total nitrogen and available nutrients decreased from top to bottom layers,and soil organic matter,total nitrogen and alkaline nitrogen were higher in the 0-20 cm soil layer,and the available phosphorus and available potassium accumulated in 0-40 cm soil layer.