提取方法对土壤可溶性有机碳测定结果的影响

发布时间：2018-03-29 09:17

  本文选题：可溶性有机碳(DOC)　切入点：振荡时间　出处：《生态环境学报》2017年11期

【摘要】：为验证浸提条件对土壤可溶性有机碳(DOC)浸提量的影响,选择具有代表性的3种土地利用方式的土壤进行实验,研究土样处理方式、提取时间、水土比、提取剂种类和振荡次数等提取条件对DOC浸提量的影响。结果表明:土样处理方式影响DOC浸提量的大小顺序为:风干过2 mm筛鲜样过1 mm筛过2 mm筛过5 mm筛不过筛,风干过2 mm筛的DOC提取量是鲜样不过筛的2.4倍,且各处理之间DOC浸提量差异性达显著水平(P0.05);DOC的浸提量随振荡时间变化不是特别明显,振荡4 h后基本达到平衡;土壤DOC浸提量随水土比的增加而增大,呈显著的线性关系;浸提剂种类对土壤DOC浸提量影响显著,4种提取剂提取出来的DOC量的大小顺序为:DOC(80℃,H_2O)DOC(25℃,0.5 mol·L~(-1) NaHCO_3)DOC(25℃,0.5 mol·L~(-1) K_2SO_4)DOC(25℃,H_2O);单次提取量随提取次数增加而降低,累积提取量随浸提次数增加而升高,且累积提取的DOC量与浸提次数呈极显著正相关。建议采用过2 mm筛的土壤鲜样,提取剂用25℃去离子水,水土比采用5∶1,连续振荡4 h后一次过滤测定土壤DOC含量。本研究有助于增强不同研究结果之间DOC数据的可比性,也有利于推动土壤DOC测定标准的完善。
[Abstract]:In order to verify the effect of extraction conditions on the extraction amount of soil soluble organic carbon (SOC), three typical land use methods were selected to study the treatment of soil samples, extraction time and water / soil ratio. The effects of extraction conditions such as the type of extractant and the number of oscillations on the extraction amount of DOC were studied. The results showed that the order of soil sample treatment affecting DOC extraction was as follows: air drying over 2 mm, fresh sample was more than 1 mm, and 2 mm was more than 5 mm. The amount of DOC extracted from the air-dried screen over 2 mm was 2.4 times that of the fresh sample, and the difference of the DOC extraction amount among the treatments reached a significant level. The extraction amount of DOC was not especially obvious with the oscillating time, and the balance was basically reached after 4 hours of oscillation. The amount of DOC in soil increased with the increase of soil and water ratio, and there was a significant linear relationship. The order of DOC quantity extracted by the four extractants was: (1) DOC = 80 鈩，

本文编号：1680494