摘要: 河流是大陆景观最为动态化的地貌构成单元,地质学家经过长期的研究,得出了一个引人注目的假说,即古生代中期曲流河的显著发育与陆生植被的繁盛存在紧密的联系,从而导致了在陆生植被对河流沉积作用影响方面的深入研究。尽管还存在一些不同的认识和争论,陆生植被对河流沉积作用的影响,得到了越来越多的地质事实的支持。立足于前人的研究成果,从陆生植被阶段的划分以及植物在古生代早中期关键的演变事件入手,介绍植被的起源和演化与河流沉积作用尤其是河流样式演变之间的耦合关系。厘清上述科学理念的变化和进步,将有助于河流相沉积的正确解释,从而为现代和古代河流过程的进一步研究提供重要的思考线索和研究途径。更为重要的是,在地球历史长河之中,有胚植物(陆生植物)在陆生大陆景观上的古生代繁殖是最为壮观的变化之一,由此而造成的全球变化包括:(1)由于岩石风化作用和碳储存的增强,将造成的大气圈二氧化碳含量的降低;(2)晚古生代冰川作用;(3)陆生营养物径流量的增加与海洋生物的灭绝事件之间的联系等。所以,陆生植被的起源与演化对河流沉积作用的影响,就成为生物沉积作用研究的一个重要主题。
关键词:
陆生植被,
植被阶段,
关键事件,
河流沉积作用
Abstract: Rivers are amongst the most dynamic geomorphological elements of the landscape.One spectacular hypothesis,i.e., the prominence of the meandering river in the Middle Paleozoic was genetically and closely related to the bloom of terrestrial vegetation, leads to the further research on the sedimentological impact of the terrestrial vegetation to fluvial deposits.Although there were some different recognitions or controversies,more and more geological facts supported that terrestrial vegetation had made obvious impact on fluvial sedimentation.On the basis of the research results finished by predecessors,this paper will introduce the coupling relationship between the origin and evolution of the terrestrial vegetation and the fluvial sedimentation especially for the change of river styles according to evolutionary stages of the terrestrial vegetation and the key events occurred in the early-middle period of the Paleozoic.Seeking these important advancements will be helpful to the right interpretation of fluvial deposits,and will provide insights for the modern and ancient fluvial processes.Furthermore,the Paleozoic colonization of terrestrial landscapes by embryophytes(land plants)was among the most profound changes in the long river of Earth history.Global changes that are genetically related to this profound change include: (1)drawdown of atmospheric CO2 due to enhanced rock weathering and carbon storage;(2)the Late Paleozoic glaciation;and (3)marine extinctions linked to increased runoff of terrestrial nutrients,and so on.Therefore,the sedimentological impact of the terrestrial vegetation on fluvial sedimentation becomes an important theme on biosedimentation studies.
Key words:
terrestrial vegetation,
vegetation stage,
key event,
fluvial sedimentation
中图分类号:
梅冥相, 刘少峰. 陆生植被对河流沉积作用的影响:生物沉积作用研究的一个重要主题*[J]. 古地理学报, 2013, 15(1): 1-10.
Mei Mingxiang, Liu Shaofeng. Sedimentological impact of terrestrial vegetation on fluvial sedimentation: An important theme on biosedimentation studies[J]. JOURNAL OF PALAEOGEOGRAPHY, 2013, 15(1): 1-10.