农业环境科学学报2017，Vol.36Issue(11)：2356-2364,9.DOI:10.11654/jaes.2017-0589
模拟水位下降与刈割对高寒湿地土壤氨氧化与反硝化微生物的影响
Effects of water table lowering and mowing on soil ammonia oxidizers and denitrifiers in alpine wetlands
摘要
Abstract
Wetlands serve as the main sources and sinks of greenhouse gases. Understanding nitrogen cycling in wetlands would greatly help in the assessment of their response and feedback to global climate change. To investigate the effect of water table lowering and mowing on soil nitrification and denitrification in wetlands, a simulated water table lowering via digging drainage ditches at different depths and mowing experiment was set up in the Zoige peatland in the eastern Qinghai-Tibetan Plateau in 2013. The abundances of ammonia-oxidizing ar-chaea, ammonia-oxidizing bacteria, and denitrifying groups were detected using a real-time PCR approach. Results based on the samples taken in July 2014 showed soil moisture decreased significantly with water table lowering. Both water table lowering and mowing significant-ly decreased soil heterotrophic respiration.The abundances of ammonia oxidizers and denitrifiers did not change under the treatments of wa-ter table lowering and mowing, whereas the ratio of abundance of AOA-amoA to AOB-amoA was significantly influenced by both mowing and interaction of mowing and water table lowering.Mowing significantly increased the relative abundance of the AOB-amoA gene but had no influence on that of the AOA-amoA gene, suggesting that the predominant role of AOB in ammonia oxidation.The abundance of nirS gene was higher than that of the nirK gene, indicating that the nirS gene was more sensitive to water table lowering and mowing. With the decline of water table, mowing promoted AOB-driven ammonia oxidation, while higher abundance of denitrifiers mitigated the accumulation of ni-trate originated from ammonia oxidation, resulting in low soil nitrate content.关键词
水位下降/氨氧化细菌/氨氧化古菌/反硝化微生物/若尔盖湿地Key words
water table lowering/ammonia-oxidizing bacteria(AOB)/ammonia-oxidizing archaea(AOA)/denitrifiers/Zoige peatland分类
农业科技引用本文复制引用
孙翼飞,沈菊培,张翠景,孙书存,贺纪正..模拟水位下降与刈割对高寒湿地土壤氨氧化与反硝化微生物的影响[J].农业环境科学学报,2017,36(11):2356-2364,9.基金项目
国家重点基础研究发展规划(973)项目(2013CB956300) （973）
国家自然科学基金项目(41371265) Project supported:National Basic Research Program of China(2013CB956300) （41371265）
National Natural Science Foundation of China(41371265) （41371265）
