本文選題：孢粉分析 + 植被特征��； 參考：《山地學報》2017年05期

【摘要】：柴達木盆地干旱已久,其西部深厚的湖相地層記錄著環(huán)境演變的過程。本文通過對大浪灘ZK06鉆孔沉積物孢粉分析,結合鈾系測年數(shù)據(jù),根據(jù)孢粉沉積運移總濃度變化、區(qū)域代表性針葉喬木植物與草本植物彼此消長的變化、蕨類植物孢子峰值出現(xiàn)等特征,探討了本區(qū)末次間冰期以來特征時期的植被演替及環(huán)境演變,并對MIS5~MIS2各階段柴達木盆地西部的氣候及環(huán)境變化進行了區(qū)域對比。初步得出柴達木盆地西部末次間冰期以來伴隨青藏高原的階段性隆升效應以及全球變化的影響下,雖然區(qū)域總體植被類型更替不太明顯,但在湖水咸化的成鹽期孢粉濃度很低,反映出干旱的成鹽期環(huán)境下植被稀少,在湖水淡化的碎屑沉積期孢粉總濃度較高,表明氣候轉為濕潤,盆地周邊山地森林面積增加和盆地草原擴張。MIS5階段以來總體趨勢為鹽層厚度逐漸增加、碎屑淤泥層厚度逐漸減少、孢粉總濃度逐漸降低、草本植物花粉百分比逐漸減少、喬木植物花粉百分比逐漸增加。由于本區(qū)受冰川融水引起河流徑流量的變化對湖水供給影響較大,導致該區(qū)湖水水質咸化與淡化以及水位升降的變化因素較為復雜。進入MIS1階段盆地西部大浪灘鹽湖完全干涸,中全新世大暖期并未出現(xiàn)湖泊水位上升和湖水淡化現(xiàn)象,可能受區(qū)域構造運動的影響控制。
[Abstract]:Qaidam Basin has been dry for a long time. The deep lacustrine strata in the west of Qaidam Basin record the process of environmental evolution. Based on the sporopollen analysis of ZK06 borehole sediments in Dangtan and the data of uranium series dating, according to the change of the total concentration of sporopollen sediment migration, the variation of the growth and decline of regional representative coniferous Arbor plants and herbaceous plants is discussed in this paper. The vegetation succession and environmental evolution during the characteristic period since the last interglacial period in this area were discussed. The climatic and environmental changes in the western Qaidam basin at various stages of MIS5~MIS2 were compared. Under the influence of the stage uplift effect of Qinghai-Xizang Plateau and global change since the last interglacial period in the western Qaidam Basin, although the change of the regional total vegetation type is not obvious, the sporopollen concentration in the salt-forming period of the lake water is very low. The results showed that the vegetation was scarce in the arid salt-forming period, and the total concentration of sporopollen in the detrital depositional period of lake water desalination was relatively high, which indicated that the climate became humid. The increase of forest area around the basin and the extension of grassland. MIS5 showed that the salt layer thickness gradually increased, the clastic silt layer thickness gradually decreased, the total sporopollen concentration gradually decreased, and the percentage of herbaceous pollen gradually decreased. The percentage of pollen in Arbor plants increased gradually. The variation of river runoff caused by glacial melting in this area has a great influence on the supply of lake water, which leads to the complicated factors of the salinization and desalination of lake water quality and the fluctuation of water level in this area. At the stage of MIS1, the salt lake of Dangtan in the western part of the basin dried up completely, and the lake water level rose and lake water desalination did not appear during the great warm period of the Middle Holocene, which may be controlled by the regional tectonic movement.
【作者單位】： 中國地質科學院水文地質環(huán)境地質研究所;中國地質科學院礦產(chǎn)資源研究所國土資源部鹽湖資源與環(huán)境重點實驗室;青海省柴達木綜合地質礦產(chǎn)勘查院;
【基金】：中國地質科學院基本科研業(yè)務費專項經(jīng)費(YYWF201627) 中國地質調查項目(DD20160054)~~
【分類號】：Q914

【相似文獻】

相關期刊論文 前1條

1 張文堂;張日東;俞昌民;;柴達木盆地西部邊緣地區(qū)的地層[J];地質學報;1958年01期

，

本文編號：1802901