不同年限草原撂荒地土壤理化特性研究

Studies on Soil Physical and Chemical Properties of Abandoned Land

对内蒙古锡林郭勒盟典型草原不同撂荒年限草原撂荒地土壤理化特性进行了研究。结果表明,随撂荒年限的增加,土壤有机质、全氮、碱解氮等主要养分均表现出先降低后增加的趋势,撂荒地有机碳的损失平均达到59.4%;在撂荒地表面0～20cm土层范围内,0.25～0.05mm粒径的砂粒含量逐渐增加,各撂荒地砂粒平均含量达76.84%,粉粒和粘粒含量逐渐降低,土壤机械组成出现粗化现象,保水能力降低,表层土壤容重增加而含水量低于天然草地。

The soil physical and chemical properties of natural grassland and abandoned land were studied.The results showed that the organic matter,total N,hydrolytic N increased firstly,then reduced with the increase of abandoned time.The loss of organic C got up to 59.4% in abandoned land.In 0~20cm,the content of 0.25~0.05mm sand increased gradually,the average content of sand in the abandoned land was up to 76.84%.The contents of silt and sand reduced gradually,the soil mechanical composition became coarse.The soil retaining water ability was reduced,top soil bulk density was increased,but soil water content was lower than that in natural grassland.