我国全新世泥炭α纤维素稳定碳同位素记录的对比与分析  

COMPARISON AND ANALYSES OF THE HOLOCENE PEAT α-CELLULOSE STABLE CARBON ISOTOPIC RECORDS FROM CHINA

作　　者：郭海春 田怡苹 魏士凯 易嘉慧 杨敏[1] 欧阳睿 张东良[2] 饶志国 Guo Haichun;Tian Yiping;Wei Shikai;Yi Jiahui;Yang Min;Ouyang Rui;Zhang Dongliang;Rao Zhiguo(College of Resources and Environmental Sciences,Hunan Normal University,Changsha 410081,Hunan;Xinjiang Institute of Ecology and Geography,Research Center for Ecology and Environment of Central Asia,Chinese Academy of Sciences,Vrümqi 830011,Xinjiang)

机构地区：[1]湖南师范大学资源与环境科学学院,湖南长沙410081 [2]中国科学院新疆生态与地理研究所,中国科学院中亚生态与环境研究中心,新疆乌鲁木齐830011

出　　处：《第四纪研究》2020年第5期1136-1144,共9页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:41772373);湖南省自然科学基金杰出青年基金项目(批准号:2018JJ1017)共同资助。

摘　　要：泥炭是古气候研究的宝贵材料,α纤维素稳定碳同位素(δ13Ccell)是泥炭古气候研究的常用代用指标。我国已有数个地点报道了全新世泥炭全样或单种植物δ13Ccell记录,对这些记录的古气候解译存在明显冲突。结合相应的孢粉和植物残体证据,对这些记录进行综合对比,结果发现:高山草地植被带和内陆干旱区荒漠草原植被带当中的泥炭地,全新世期间的原地植物种属构成相对稳定且未发生显著变化,因此其δ13Ccell记录具有较为明显的长期变化趋势,其古气候解译也更为可靠;森林植被带和林草交互带当中的泥炭地,全新世期间的原地植物种属构成发生过显著变化(如木本植物入侵),这可能是造成其全新世δ13Ccell记录长期趋势不明显或其古气候指示意义复杂难解的主要原因。这些结果显示了泥炭地的原地植物种属构成,对相应δ13Ccell记录的古气候解译的重要影响。同时也表明,无论是泥炭δ13Ccell研究地点的选择,还是泥炭δ13Ccell记录的古气候解译,都需重视其来源植物种属构成和变化。对于全新世泥炭δ13Ccell古气候研究,建议开展针对性的现代过程研究,尤其是优势泥炭植物种属的δ13Ccell在时间序列上的现代过程研究,以提供可靠的古气候解译基础。Peat is a precious archive for paleoclimatic studies.The stable carbon isotopic composition of peatα-cellulose(δ13Ccell)has been widely adopted for paleoclimatic studies.There are several Holoceneδ13Ccell records of bulk peat samples or residues of a specific plant species have been reported in China,including theδ13Ccell records from the Sahara sand peatland,Big Black peatland,Narenxia peatland in the Altai Mountains in northern Xinjiang region,the Chaiwobu peatland in the Tianshan Mountains in central Xinjiang region,the Hongyuan peatland in the northeastern Qinghai-Tibet Plateau,the Yuexi peatland in Southwestern China,the Dajiuhu peatland in Central China,and the Hani peatland in Northeastern China.However,both the obtainedδ13Ccell records themselves and the paleoclimatic interpretations of theδ13Ccell records,are quite different.In this paper,combined with the relevant evidence of pollen and plant marcofossils,theδ13Ccell records are carefully compared and analyzed.The results demonstrated that,in the peatlands in the alpine meadow zone and the arid inland desert-grass zone,the composition of plant species of the in situ vegetation was relative stable that without significant variations during the Holocene,and therefore the Holoceneδ13Ccell records from these peatlands have apparent long-term change trends,which could be paleoclimatically interpreted easily.However,in the peatlands in the forest zone and the forest/grassland transitional zone,the composition of plant species of the in situ vegetation experienced significant variations(for example,the invasion of woody plants into the peatland)during the Holocene,that's might the main reason why the Holoceneδ13Ccell records from these peatlands without apparent long-term change trends and the paleoclimatic significance of these Holoceneδ13Ccell records cannot be determined easily.All the results highlight the important influence from the plant composition of in situ peat vegetation on the paleoclimatic interpretations of peatδ13Ccell records.Theref

关 键 词：泥炭 全新世 α纤维素 稳定碳同位素 植被 古气候 

分 类 号：P595[天文地球—地球化学] P532[天文地球—地质学]