柴达木盆地可鲁克湖沉积物表层花粉散布规律及其对区域植被的指示意义  

Surface Pollen Distribution and Ecological Significance in Hurleg Lake,Qaidam Basin

作　　者：李鸿宇 魏海成[1,3] 成艾颖 樊启顺[1] 段荣蕾[1,2] LI Hongyu;WEI Haicheng;CHENG Aiying;FAN Qishun;DUAN Ronglei(Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes,Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining,810008,China;University of Chinese Academy of Science,Beijing,100049,China;Qinghai Province Haixi Mongolian and Tibetan Autonomous Prefecture Salt Lake Administration,Delingha,817000,China)

机构地区：[1]中国科学院青海盐湖研究所,青海省盐湖地质与环境重点实验室,青海西宁810008 [2]中国科学院大学,北京100049 [3]青海省海西蒙古族藏族自治州盐湖管理局,青海德令哈817000

出　　处：《盐湖研究》2024年第1期66-75,共10页Journal of Salt Lake Research

基　　金：青海省杰出青年基金项目(编号:2023-ZJ-941J);国家自然科学基金面上项目(编号:42172019)。

摘　　要：可鲁克湖是柴达木盆地东部荒漠区重要的生态屏障,对全球气候变化响应十分敏感。利用沉积物化石花粉重建湖泊生态系统演变历史及其对全球气候变化响应过程和机制的分析是当前重要的研究方向,本研究系统采集了可鲁克湖沉积物表层样品开展花粉分析。研究结果显示,花粉组合以藜科、禾本科、蒿属、莎草科为主。花粉总浓度在湖泊沉积中心及偏西南区域显著偏高,其中藜科、莎草科、蒿属、白刺属、麻黄属、紫菀属花粉与总浓度变化特征较为一致,而禾本科花粉在湖泊东南部显著富集。湖泊沉积物中的藜科和蒿属花粉较好地指示了柴达木盆地东部灌木-矮灌木荒漠和荒漠草原整体植被特征,而禾本科和莎草科花粉主要指示湖岸周边隐域性沼泽和河滩草甸植被群落;白刺属花粉对湖泊北岸一级阶地上的白刺群落发育和湖面变化具有较好的指示意义,谷物类禾本科和十字花科花粉能较为灵敏地反映湖泊附近的农耕活动,桦木属和云杉属花粉则主要由风力和河流远距离输入。研究揭示了可鲁克湖水深、水动力条件、湖岸周围植被群落分布以及风力作用是影响花粉散布和沉积的重要影响因素,此项研究也为青藏高原湖泊沉积物花粉组合的精确解译提供了重要数据资料和分析依据。Hurleg Lake is a critical ecological barrier located in the desert region of the eastern Qaidam Basin,which is sensitivity to global climate change.The study of modern pollen processes in lake sediments is a prerequisite for reconstructing the evolutionary history of lake ecosystems and their responses to environmental change.Here,we systematically collected surface sediment samples from Hurleg Lake and conducted pollen analysis,revealing that the pollen assemblages were dominated by Chenopodiaceae,Poaceae,Artemisia,with a notably higher concentration in the sedimentary center of the lake and the southwestern region.Chenopodiaceae and Artemisia pollens were identified as important indicators of the shrub-dwarf shrub desert and desert steppe vegetation in the eastern Qaidam Basin,while Poaceae and Cyperaceae predominantly reflected the azonal marshes and river beach meadows around the lakeshore.Furthermore,Nitraria pollen was found to be a useful indicator of the development of the Nitraria community and lake level fluctuation on the first terrace in the northern part of the lake bank.Cerealia Poaceae and Brassicaceae pollens were identified as sensitive indicators of farming activities around the lake,while Betula and Picea pollens were primarily transported by wind.It is worth noting that pollen distribution and deposition is significantly influenced by factors such as water depth,hydrodynamic conditions,vegetation community distribution around the lake,and wind action.Our study provides important modern process data and a theoretical basis for the accurate interpretation of pollen assemblages in lake sediments of the Qinghai-Xizang Plateau,contributing to our understanding of vegetation and environmental changes in the Qaidam Basin.

关 键 词：花粉 可鲁克湖 青藏高原 湖泊沉积物 柴达木盆地 

分 类 号：Q948[生物学—植物学] P532[天文地球—古生物学与地层学]