应用生态学报2018，Vol.29Issue(3)：857-864,8.DOI:10.13287/j.1001-9332.201803.023
稻田土壤有机碳矿化及其激发效应对磷添加的响应
Responses of organic carbon mineralization and priming effect to phosphorus addition in paddy soils
摘要
Abstract
To understand the coupled controlling of carbon (C) and phosphorus (P) on the mineralization of soil organic carbon and amended substrates in paddy soil,we investigated the effects of P addition on the decomposition of organic carbon and its induced priming effect by using 13C isotope probing technique in microcosm. The results showed that P addition accelerated the release of CO2 but inhibited the release of CH4,leading to 53.1％ reduction of total accumulated CH4 and 70.5％ reduction of the 13CH4 derived from exotic glucose-13 C. P addition altered the carbon distribution during the microbial turnover progress,with 3.6％ of glucose-13C being transferred into the labile carbon pool,therein significantly increased potential of the mineralization rate of exogenous C. A transient negative priming effect was observed in the early stage of incubation. With time prolonging,the priming effect on CO2 emission (PECO2) generally increased and then decreased after a peak. The priming effect on CH4 emission (PECH4) kept increasing and finally fluctuated at a relative stable value until the end of the experiment (100 days). P addition increased PECO2 by32.3％ but reduced PECH4 by 93.4％. Results from the RDA and Pearson analysis showed that electric conductivity,oxidation-reduction potential and dissolved organic carbon significantly affected soil C mineralization. There were significantly negative correlations between available phosphorus(Olsen-P) and 13CH4,and between Olsen-P and PECH4. In conclusion,with the addition of exogenous organic matter,P application could reduce CH4 emissions and inhibit its priming effect,accelerate the mineralization of SOC,probably improve the nutrient supply,and thus enhance the availability of organic C and promote C cycling in paddy soil.关键词
稻田土/有机碳矿化/磷添加/激发效应Key words
paddy soil/organic carbon mineralization/phosphorus addition/priming effect引用本文复制引用
唐美玲,魏亮,祝贞科,李欢,周萍,葛体达,吴金水,王光军..稻田土壤有机碳矿化及其激发效应对磷添加的响应[J].应用生态学报,2018,29(3):857-864,8.基金项目
本文由国家自然科学基金项目(41430860,41371304)、中国科学院战略性先导科技专项(XDB15020401)和湖南省自然科学基金项目(2016JJ3132)资助 （41430860,41371304）
