在我国西北地区、西藏一带的土壤中常含有石膏成份,一般含量在1%左右,但在石膏盐盘中则可达30%以上。了解土壤中的石膏含量,对于划分某些土壤类型是很重要的。目前测定石膏含量仍是把石膏从土壤中浸提分离出来,通过测定硫酸根含量再换算成石膏量。测定硫酸根的方法有重量法、容量法[1]、比浊法[2]、电导法[3]以及原子吸收光谱法[4]等方法。重量法精度 In the northwestern region of our country, the soil in the vicinity of Tibet often contains gypsum, which generally contains about 1%, but can reach more than 30% in the gypsum salt pan. Understanding the amount of gypsum in the soil is important for classifying some soil types. The current determination of gypsum content is still gypsum from the soil leaching out, by measuring the sulfate content and then converted into gypsum amount. Determination of sulfate methods are gravimetric method, volumetric method [1], turbidimetric method [2], conductivity method [3] and atomic absorption spectrometry [4] and other methods. Gravimetric accuracy