摘要
研究降雨格局(如降雨量和降雨时间)对滨海盐沼湿地土壤碳矿化的影响,对于深入理解土壤碳的稳定性和积累机制具有重要意义。本研究选取远离海岸且不受潮汐影响的黄河三角洲原生盐地碱蓬盐沼湿地为对象,通过野外原状土柱的控制试验,分析土壤碳矿化(CO2和CH4通量)在不同时期(干旱期和湿润期)对降雨事件的响应。结果表明:降雨时间和降雨量对土壤CO2通量的影响存在交互作用。在干旱期,大降雨事件显著降低了土壤CO2通量;而湿润期的降雨事件对土壤CO2通量没有显著影响,这可能与盐沼湿地的水盐运移有关。降雨量、降雨时间及其交互作用均对土壤CH4通量没有显著影响。降雨时间和降雨量对CH4/CO2比率均没有显著影响,但是相关分析表明随着土壤含水量和盐分的升高,CH4/CO2比率呈升高趋势。随着降雨量的增加,土壤含水量和土壤盐分都显著增加,且两因素呈现显著的正相关关系。因此,未来该地区降雨体系改变将可能通过调控土壤水盐运移等条件对该滨海湿地土壤碳矿化和碳汇功能产生深远影响。
Studying the effects of rainfall regimes such as rainfall amount and timing on soil carbon mineralization is of great importance for our understanding the mechanisms underlying the stability and accumulation of soil carbon in coastal salt marshes. In this study, we examined the responses of soil carbon mineralization(CO2 and CH4 fluxes) from undisturbed soil columns to rainfall events in different seasons(dry and wet seasons) with filed experiments in a primary Suaeda salsa region in the Yellow River Delta salt-marsh wetland, which is far away from the coast and not affected by tides. The results showed that rainfall amount and timing had a significant interaction in affecting soil CO2 flux rates. During the dry season, large rainfall events significantly reduced soil CO2 flux rates but had no significant effect in the wet season, which might be closely related to the significant increase in soil water content and salinity. Rainfall amount, rainfall timing and their interactions had no significant effect on soil CH4 efflux rates. Rainfall timing and rainfall amount did not affect CH4/CO2. CH4/CO2 increased with increasing soil water content and salinity. Soil water content and soil salinity showed similar increases to increasing rainfall amount. Our results suggested that the changing rainfall regime under climate change in the future would have a great impact on soil carbon mineralization and carbon sink function by regulating soil water and salt migration in this region.
作者
李雪
董杰
李培广
王晓杰
韩广轩
宋维民
LI Xue;DONG Jie;LI Pei-guang;WANG Xiao-jie;HAN Guang-xuan;SONG Wei-min(College of Environment and Planning,Liaocheng University y Liaocheng 252059,Shandong,China;CAS Key Laboratory of Coastal Environmental Processes and Ecological Restoration,Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences(CAS),Yantai 264003,Shandong,China;Yellow River Delta Research Station of Coastal Wetland Ecology,Chinese Academy of Sciences,Dongying 257500,Shandong,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2021年第2期581-590,共10页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(41706097)
国家自然科学基金委员会-山东联合基金项目(U1906220)
中国科学院“十三五”信息化建设专项(XXH13506)资助。
关键词
降雨体系
气候变化
黄河三角洲
盐沼湿地
碳汇
土壤碳矿化
rainfall regime
climate change
the Yellow River Delta
salt marsh
carbon sink
soil carbon mineralization
