3种不同类型水稻土溶解性有机碳生物降解特性研究 - 国家生态系统 .pdfVIP

中国农学通报 2012,28(12):29-32 Chinese Agricultural Science Bulletin 3种不同类型水稻土溶解性有机碳生物 降解特性研究 禹洪双，刘 勤，陈武荣，张亚楠，胡安永，曹志洪 （中国科学院南京土壤研究所，南京210008 ） 摘 要：为了解水稻土DOC 生物降解特性及其在农田生态系统碳循环中的作用，采用室内培养试验，研 究了3 种不同类型水稻土（红壤性水稻土、黄泥土、乌栅土）溶解性有机碳(DOC)的含量及其生物降解特 性。结果表明：不同类型水稻土DOC 含量为31.64~49.25 mg/kg ，其中乌栅土DOC 含量略高于黄泥土， 红壤性水稻土最低；经过42 天的培养，3 种水稻土DOC 的生物降解率为54.8%~66.6% ，表现为：黄泥土 大于乌栅土和红壤性水稻土。3 种水稻土DOC 降解数据符合双指数衰变模型，DOC 分别由降解速率不 同的2 个库组成：易分解部分（周转时间1~2 天）和难分解部分（周转时间64~278 天）。培养过程中，DOC 溶液中结构较复杂的芳环物质比例前期呈上升趋势，后期趋于稳定略有下降，这与其中易降解组分的降 解有关。 关键词：水稻土；溶解性有机碳；含量动态；生物降解；UV280 中图分类号：S153.6 文献标志码：A 论文编号：2012-0511 BiodegradationofDissolvedOrganicCarbonDerivedfromThreeKindsofPaddySoils Yu Hongshuang, Liu Qin, Chen Wurong, Zhang Ya ’nan, Hu Anyong, Cao Zhihong (InstituteofSoilScience,ChineseAcademyofSciences, Nanjing 210008) Abstract: In order to understand the biodegradation and the role of DOC in carbon cycle in farmland ecosystems, with incubation experiments, the author selected three kinds of paddy soil which were the red paddy soil, huangni soil and wushan soil, and then extracted the DOC from paddy soil to estimate the biodegradation of the DOC. The results showed that: the DOC content and three kinds of paddy soils were 31.64-49.25 g/kg, wushan soil had a slightly higher DOC content than huangni soil, while red paddy soil had the lowest DOC content. During the 42 days of incubation, there was a broad range of biodegradation DOC (from 54.8% to 66.6% of total DOC), and decreased in the order of huangni soil, wushan soil, red paddy soil. The law was consistent with a double exponential decay model. DOC was composed of two different