生态与农村环境学报2017，Vol.33Issue(11)：983-991,9.DOI:10.11934/j.issn.1673-4831.2017.11.004
天宝岩长苞铁杉倒木微生物生物量和可溶性有机碳氮的变化
Dynamics of Microbial Biomass and Dissolved Organic Carbon /Nitrogen in Downed Logs of Tsuga longibracteata in the Tianbaoyan National Nature Reserve, China
摘要
Abstract
Downed logs are important carbon and nutrient pools in forest ecosystems. Monitoring of dynamics of microbial biomass and dissolved organic carbon/nitrogen are of great significance to in-depth understanding of the mechanism of downed log decomposition. Microbial biomass carbon ( MBC) , microbial biomass nitrogen ( MBN) , dissolved organic car-bon (DOC), dissolved organic nitrogen (DON), and ratio of carbon to nitrogen in bark, sapwood and heartwood of downed T. longibracteata logs various in decaying degree from Grade I to Grade V in the Tianbaoyan National Nature Re-serve, Fujian Province of China was analyzed. Results show:(1) The downed logs varied from 7. 41% to 63. 27% in wa-ter content, and were 311. 66-564. 87, 2. 34-5. 82 and 0. 09-0. 35 g·kg-1, respectively, in organic carbon, TN and TP; ( 2) In terms of MBC and MBN, the three components of the highly decayed downed logs ( GradesⅣandⅤin deca-ying degree) displayed an decreasing order of heartwood > sapwood > bark; ( 3) Sapwood and heartwood was higher in DOC than bark of the logs the same in decaying degree, while sapwood was higher in DON than bark and heartwood, ex-cept for logs of Grade Ⅱ in decaying degree;( 4) Microbial biomass C/N ratio in heartwood varied sharply between logs different in decaying degree, whereas DOC/DON ratio in sapwood did;(5) Position in the log, decaying degree and their interactions all had remarkable impacts on MBC, MBN, DOC, DON, MBC/MBN and DOC/DON ( P<0. 01 ); and (6) MBC, DOC and DON were extremely and positively related to water content in the log (P<0. 01), whereas NBC/MBN and DOC/DON negatively to TP in the log ( P<0. 05) . To sum up, during the downed log decaying or decomposing process, water content is the major factor affecting MBC, MBN, DOC and DON in decaying downed logs.关键词
天宝岩国家级自然保护区/长苞铁杉/倒木/微生物生物量/可溶性有机碳/可溶性有机氮Key words
Tianbaoyan National Nature Reserve/Tsuga longibracteata/downed log/microbial biomass/dissolved or-ganic carbon/dissolved organic nitrogen分类
农业科技引用本文复制引用
肖石红,何东进,刘进山,吴建勤,蔡昌棠,游巍斌,沈云强,简立燕,严思晓..天宝岩长苞铁杉倒木微生物生物量和可溶性有机碳氮的变化[J].生态与农村环境学报,2017,33(11):983-991,9.基金项目
国家自然科学基金(31370624) （31370624）
国家教育部博士学科点基金(20103515110005) （20103515110005）
福建省自然科学基金(2008J0116,2011J01071) （2008J0116,2011J01071）
