黄河三角洲典型滨海盐沼湿地土壤CO_(2)和CH_(4)排放对水盐变化的响应  

Response of soil CO_(2) and CH_(4) emissions to changes in moisture and salinity at a typical coastal salt marsh of Yellow River Delta

作　　者：李雪 董杰[3] 韩广轩[1,2] 张奇奇 谢宝华 李培广[1,2] 赵明亮 陈克龙[4] 宋维民 LI Xue;DONG Jie;HAN Guang-Xuan;ZHANG Qi-Qi;XIE Bao-Hua;LI Pei-Guang;ZHAO Ming-Liang;CHEN Ke-Long;SONG Wei-Min(Key Laboratory of Coastal Environmental Processes and Ecological Restoration,Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences,Yantai,Shandong 264003,China;Yellow River Delta Field Observation and Research Station of Coastal Wetland Ecosystem,Chinese Academy of Sciences,Dongying,Shandong 257000,China;School of Geography and Environment,Liaocheng University,Liaocheng,Shandong 252000,China;School of Geography Science,Qinghai Normal University,Xining 810000,China)

机构地区：[1]中国科学院烟台海岸带研究所,海岸带环境过程与生态修复重点实验室,山东烟台264003 [2]中国科学院黄河三角洲滨海湿地生态系统野外科学观测研究站,山东东营257000 [3]聊城大学地理与环境学院,山东聊城252000 [4]青海师范大学地理科学学院,西宁810000

出　　处：《植物生态学报》2023年第3期434-446,共13页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金委员会-山东联合基金项目(U1906220);国家自然科学基金(41706097);国家重点研发计划(2019YFD0900703)。

摘　　要：滨海盐沼湿地是重要的“蓝碳”碳汇,研究水盐变化对土壤碳矿化(CO_(2)和CH_(4)排放)的影响,对理解滨海盐沼湿地的碳汇稳定机制具有重要意义。该研究选取黄河三角洲典型盐沼湿地土壤为研究对象,通过水盐梯度模拟实验,研究土壤碳矿化、理化性质、微生物生物量及群落结构对不同土壤水分和盐分含量的响应。主要结果:(1)水盐变化对土壤CO_(2)、CH_(4)排放量以及CH_(4):CO_(2)的影响均不存在交互作用,CO_(2)排放量随土壤含水量增加呈先升后降的单峰型变化趋势,盐分含量升高则显著抑制CO_(2)排放;水分含量升高对CH_(4)排放具有显著促进作用,盐分升高则显著抑制CH_(4)排放。(2)水盐变化对土壤可溶性有机碳(DOC)含量具有弱交互作用,在低水分处理下,DOC随着土壤盐分的增加呈减少趋势,但在高水分处理下呈增加趋势;CO_(2)排放与DOC含量呈显著正相关关系,而CH_(4)排放与DOC含量没有显著相关性。(3)土壤微生物生物量随水分含量的增加呈先增加后降低的变化趋势,随盐分含量的升高则显著降低;且相比于CH_(4)排放, CO_(2)排放量与微生物生物量具有更高的相关关系。(4)水盐变化显著改变了土壤微生物群落结构,细菌数量和α多样性指数均随水分含量升高而显著增加,随盐分含量升高则显著降低;同时发现土壤CO_(2)、CH_(4)排放均与细菌数量、α多样性指数具有显著正相关关系。因此,在该地区气候暖干化背景下,土壤水盐条件变化将可能通过调控土壤理化性质、微生物生物量及群落结构等条件对该滨海盐沼湿地碳汇功能产生深远影响。Aims Globally,coastal salt marshes have been considered as major blue carbon sinks and contributors for climate change mitigation.Understanding the effects of soil moisture and salinity on soil CO_(2)and CH_(4) emissions will advance better understand of long-term storage of soil carbon in coastal salt marshes.Methods We conducted a simulation experiment with a gradient of water treatments(25%,50%,75%and 100%soil saturated water content)and salt treatments(9 g·kg-1and 18 g·kg-1).And we investigated soil carbon mineralization rates,soil properties,microbial biomass and community structure of typical salt marsh soils in the Yellow River Delta.Important findings We found that:(1)There was no interaction between soil moisture and salinity content on soil CO_(2),CH_(4) emissions and CH_(4):CO_(2),and soil CO_(2) emissions showed a unimodal curve along the soil moisture gradients and a significant decrease with increasing soil salinity content.The increased soil moisture significantly promoted soil CH_(4) emissions,but the increased soil salinity content significantly inhibited soil CH_(4)emissions.(2)There was a weak significant interaction between moisture and salinity content on dissolved organic carbon(DOC).Under low water treatment,DOC content decreased with increasing soil salinity content,but increased under high water treatment.There was a significant positive relationship between soil CO_(2) emissions and DOC content.(3)Soil microbial biomass exhibited a trend of first increasing and then decreasing with the increasing soil moisture,while soil salinity content significantly decreased microbial biomass.There was a significant positive correlation of microbial biomass with CO_(2) and CH_(4) emissions.(4)Both soil moisture and salinity treatments modified soil microbial community structure.Soil moisture and salinity treatments significantly increased and decreased the number of bacteria andαdiversity index,respectively.Both soil CO_(2) and CH_(4) emissions were positively correlated with the number of bacteria

关 键 词：土壤含水量 盐度 土壤碳矿化 滨海盐沼湿地 黄河三角洲 蓝碳 

分 类 号：X144[环境科学与工程—环境科学]