本文選題：孢粉分析 + 植被特征��； 參考：《山地學(xué)報(bào)》2017年05期

【摘要】：柴達(dá)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(guò)程。本文通過(guò)對(duì)大浪灘ZK06鉆孔沉積物孢粉分析,結(jié)合鈾系測(cè)年數(shù)據(jù),根據(jù)孢粉沉積運(yùn)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(zhǎng)的變化、蕨類(lèi)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(lái)特征時(shí)期的植被演替及環(huán)境演變,并對(duì)MIS5~MIS2各階段柴達(dá)木盆地西部的氣候及環(huán)境變化進(jìn)行了區(qū)域?qū)Ρ�。初步得出柴達(dá)木盆地西部末次間冰期以來(lái)伴隨青藏高原的階段性隆升效應(yīng)以及全球變化的影響下,雖然區(qū)域總體植被類(lèi)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(zhuǎn)為濕潤(rùn),盆地周邊山地森林面積增加和盆地草原擴(kuò)張。MIS5階段以來(lái)總體趨勢(shì)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(duì)湖水供給影響較大,導(dǎo)致該區(qū)湖水水質(zhì)咸化與淡化以及水位升降的變化因素較為復(fù)雜。進(jìn)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(gòu)造運(yùn)動(dòng)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(guó)地質(zhì)科學(xué)院水文地質(zhì)環(huán)境地質(zhì)研究所;中國(guó)地質(zhì)科學(xué)院礦產(chǎn)資源研究所國(guó)土資源部鹽湖資源與環(huán)境重點(diǎn)實(shí)驗(yàn)室;青海省柴達(dá)木綜合地質(zhì)礦產(chǎn)勘查院;
【基金】：中國(guó)地質(zhì)科學(xué)院基本科研業(yè)務(wù)費(fèi)專(zhuān)項(xiàng)經(jīng)費(fèi)(YYWF201627) 中國(guó)地質(zhì)調(diào)查項(xiàng)目(DD20160054)~~
【分類(lèi)號(hào)】：Q914

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1 張文堂;張日東;俞昌民;;柴達(dá)木盆地西部邊緣地區(qū)的地層[J];地質(zhì)學(xué)報(bào);1958年01期

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本文編號(hào)：1802901