浸提条件对土壤溶解性有机碳测定结果的影响  

Effects of extraction conditions on the concentration of dissolved organic carbon in soil

作　　者：李亚林 练金山 任凤玲 孙楠[1] 徐明岗[1] LI Yalin;LIAN Jinshan;REN Fengling;SUN Nan;XU Minggang(National Engineering Laboratory for Improving Quality of Arable Land,Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]中国农业科学院农业资源与农业区划研究所/耕地培育技术国家工程实验室,北京100081

出　　处：《农业资源与环境学报》2022年第4期741-748,共8页Journal of Agricultural Resources and Environment

基　　金：国家重点研发计划项目(2017YFC0503805);国家自然科学基金项目(41620104006);中央级公益性科研院所基本科研业务费(Y2017LM06)。

摘　　要：为探明不同浸提条件下土壤溶解性有机碳(DOC)测定含量和浸提率的变化规律,增强各研究结果之间DOC测定含量的可比性。基于已公开发表的31篇文献,建立了包含不同浸提条件下DOC测定含量(547组)和浸提率(390组)的数据库。采用数据整合分析方法(Meta-analysis),量化不同浸提条件(浸提剂种类、浸提温度、水土质量比等)对DOC测定含量和浸提率的影响程度并分析了DOC测定含量与土壤性质之间的关系。结果表明,浸提剂种类对DOC测定含量和浸提率具有显著影响,与去离子水相比,KCl和K2SO_(4)试剂均显著提高了浸提液中DOC测定含量(124.1%和118.8%)和浸提率(65.3%和17.2%),CaCl_(2)显著降低了DOC测定含量(57.9%)和浸提率(45.2%)。与室温条件(25℃)相比,提高温度可以显著提升DOC测定含量(72.5%)和浸提率(65.2%),且DOC增加量随温度的升高呈现出先减小后增大的趋势。DOC测定含量和浸提率均随浸提时间、土壤研磨粒径、水土质量比的增大而增加,且DOC增加量与水土质量比呈极显著的线性相关。DOC测定含量和浸提率与土壤pH、有机碳、全氮等显著相关。综上,DOC测定含量和浸提率受土壤性质及浸提条件的显著影响,在测定DOC含量时适宜采用KCl作为浸提剂,在室温条件(25~30℃)下浸提1 h。To investigate the driving factors of the concentration of dissolved organic carbon(DOC)and its extraction efficiencies under different extraction conditions is conducive to enhancing the comparability of DOC concentration among the results of various research studies.A database containing DOC determination content(547 pairs)and extraction rate(390 pairs)under different extraction conditions was established based on 31 previously published studies.The influence of different extraction conditions(e.g.,extractant,extraction temperature,water-to-soil ratio)on DOC determination content and extraction rate was quantified and the relationship between DOC determination content and soil properties was analyzed.Compared with deionized water,both KCl and K2SO_(4) significantly improved the DOC concentration(by 124.1%and 118.8%,respectively)and extraction efficiencies(by 65.3%and 17.2%,respectively),while CaCl_(2) significantly reduced the DOC concentration(by 57.9%)and extraction efficiency(by 45.2%).A comparison of these values at room temperature(25℃)showed that the DOC concentration and extraction efficiencies increased(by 72.5%and 65.2%,respectively)with the increase in the DOC extraction temperature.Moreover,the DOC increment showed a trend of first decreasing and then increasing with the increase in temperature.In addition,both the DOC concentration and extraction efficiencies increased as the extraction time,soil particle size,and water-to-soil ratio increased.There were significant correlations between soil organic carbon and total nitrogen levels and pH,the important explanatory variables for the increase in DOC concentrations.The content of DOC extracted and the extraction rate were significantly affected by soil properties and extraction conditions.Therefore,when determining DOC content,KCl is suitable for extraction at room temperature(25~30℃)for 1 h.

关 键 词：土壤 溶解性有机碳 浸提条件 浸提率 水土质量比 整合分析 

分 类 号：S153.6[农业科学—土壤学]