土壤中水溶性有机碳测定中的样品保存与前处理方法

对棕壤、褐土和红壤样品研究结果表明 ,土壤水溶性有机碳 (WSOC)在中雨停止 72小时后几乎恢复到正常水平 .采集的土样应尽快测定 .如须保存 ,则以冷藏为好 ,同时要避免水分丧失 .样品测试直接用鲜样进行 ,其中水分和大于 1mm颗粒物对结果的干扰可通过校正排除 .提取时间则以 5h为宜

Soil sample preservation and pretreatment for water soluble organic carbon determination

Methods for soil sampling, preservation and pretreatment and the extraction duration for water soluble organic carbon (WSOC) determination in soils were investigated. Also, the effect of precipitation event on the determination was discussed. For the measurement of WSOC, soil samples should not be collected 72 h after a rain event and should be measured without air-drying. Sealed refrigeration is necessary if the samples have to be preserved for a few days. Five-hour-continuous shaking is suggested for a complete extraction. However, for calibrating the effect of stones the particles(larger than 1mm in size) in residues after each extraction should be weighed.