Geological Events and Mammalian Distribution in China
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动物学报 48 (2) :141～153 , 2002 Acta Zoologica S inica 综 述 GEOLOGICAL EVENTS AND MAMMALIAN DISTRIBUTION IN CHINA ZHAN G Rong2Zu ( Yong2Zu) ( Instit ute of Geographical Science and Resources , Chinese Academy of Sciences , Beijing 100101 , China) Abstract I utilized the results of research on the distribution patternsof mammalian species in China , incorporating these information as biological evidences in the study of paleo2environmental change. I used a method of quantitative mapping for the analysis. The examples discussed in this article illustrate how geological events and resulting environmental patterns and other changes have affected animal distributions. Key words Distribution pattern , Geological events , Zonal landscape system , Barrier , Transition , Zoogeography ( Tang , 1995) . Consequently , following three great 1 Introduction natural divisions of continental China have been For biogeographic studies , seeking patterns is established ( Plate Ⅰ) . the most basic task , followed by seeking to explain 1 ) Eastern Monsoon China It is generally what processes produced those patterns. The dominated by monsoon humid climate and forest objective of this study is to shed light on a simple vegetation. A seriesof west to east trending mountain relationship; animal distributions are the result of ranges —the Yinshan Mts. , the Qinling Mts. , and adaptation to processes of geological and paleo2 the Nanling Mts. —serve as barriers between the environmental change. The common characteristic of great climatic zones of temperate (Northeast China) , modern biogeographic distributions is that they are warm temperate (North China) , subtropical (Central the evolutionary product of adaptation to an ever and Northern South China) and tropical ( Southern changing environment. South China ) . The most distinct barrier is the 111 Geological events and their geographical Qinling Mts.2Huai River line , which has formed an consequences in China important physical geographical division between Since the beginning of the Tertiary Period, and north and south in eastern China since the Pleistocene the disappearance of the Tethys Sea resulting from ( Zhou , 1984 ) . In conformity with world2wide joining of the Eurasian plate and the Indian plate , climatic fluctuations , shifting of climatic zones was there have been tremendous changes in the geological manifested latitudinally in this realm. With minor structure and geographical environments of exceptions , the great tendency in this shifting was for continental China. The thrusting of the Indian plate the tropical, humid rainforest zone to regress underneath the Eurasian plate , and the impacts of the southwards since the Early Pleistocene from the Himalayan tectonic movements since the Miocene Changjiang river area to the southernmost border in epoch have been dominant forces in shaping the latest the Late Pleistocene , and then move slightly stage of Chinese physical environment (Liu et al ., northwards in the present time (Liu et al ., 1984) . 1984) . The uplift of the lofty Tibetan ( Qinghai2 The cold temperate climatic zone , part of the Xizang) Plateau has been the major cause of the periglacial taiga of the Siberia, has expanded formation of the modern monsoon system in East Asia southward to Northeast China in the Early Received 20 January, 2002; revised 26 February , 2002 Brief introduction of the author Professor. Research interest : biogeography. © 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. 241 动 物 学 报 48 卷 Pleistocene, and then retreated back to the (Shi , 1991) . In the course of uplift and climatic northernmost section of that area since the Middle fluctuation, the forest has in general retreated from Pleistocene. Obviously, this realm has not been the interior of the plateau to the southeastern lower covered by continental ice sheet and served as a margin , while the original landscape of the refugium —“Pantu Ground”( Kahlke , 1961) . southeastern margin has undergone vertical shifting The Loess Plateau in the middle reaches of the ( Zhang et al . , 1981 ) . Climatically , the Yellow River indicates an expansion of dry2cold southeastern flank of the Himalayan and Hengduan is climate, with the loess dust source being the attributed to the monsoon realm. However, Northwestern Arid China area, since the Early topographically , the Himalayas are inseparable from Pleistocene ( Li , 1998 ) . Interposed between the Tibetan Plateau. northeastern China and southeastern China areas the 112 Distribution patterns of land vertebrates in Loess Plateau area is climatically semiarid , while the China loess deposit plain of the north China plain is semi2 Based on investigation and study of entire species humid in the present time. ranges , the most obvious patterns in the distribution 2) Northwestern A rid China The so2called of existing land vertebrates in China , apart from pan2 Dry pole of Asia, named by the German geographer tropic and pan2boreal patterns, is a tendency of Troll, is located in southern Xinjiang (Li , 1998) . geographical diversification ( Zhang , 1999) . There Areal differentiation within this realm is related are nine main patterns occurring , showing a great mainly to decreasing moisture conditions from east to extent of congruence with geographical regionalization west as shown in the vegetation sequence of semi2 of China at different scales , and which can be divided arid/ steppe , arid/ steppe2desert and extremely arid/ into two major categories : ( 1 ) four great zonal desert. Since the Late Cretaceous and the early patterns: Boreal , Central Asian , Oriental , and Old Tertiary , a general trend of desiccation in northwest world Tropical ; and ( 2 ) five regional patterns : China has occurred , accelerated by the rain2shadow Highland , Himalayan2Hengduan, Southern China , created by the uplift of Tibetan plateau since the Northeast China and Continental Island. Each Early Pleistocene (Shi et al ., 1995) . pattern is based on occurrence of characteristic or 3) Tibetan Frigid Plateau This , the highest endemic species, but some species range further plateau in the world with alpine climate and outside of the main spheres of the patterns , vegetation , is characterized mainly by cold steppe and depending on barrier effects of physical environment cold desert in the inner part, while in the or dispersal abilities of species in the continent. southeastern margin of the plateau , the Himalayan2 Thus, a transition zone must be built up between two Hengduan mountain system, is distinguished by adjacent patterns. Furthermore, based on faunal vertical natural zones from tropical or subtropical dominance as a whole , they belong to either forests in deep river gorges to alpine tundra. The Palaearctic and Indomalayan (Oriental) realms , the plateau was almost non2existent during the Pliocene. concept of which has been recognized by Since the middle Quaternary , and up to the present , biogeographers since the time of Wallace (Darlington , it had reached from an average elevation of 3 000 m 1957) . The relationship of the nine patterns can be to more than 4 000 m above sea level. The continued shown in Fig. 11 Although there remain insufficient uplift of the plateau has intensified the alpine climate data for a few rare species which are treated as itself , and increased the forces of aridity in the inner exceptions , it provides basic facts as generalization for part of the plateau. The vestiges of Pleistocene one of the starting points in further study. A more glaciations are restricted to some valley glaciers , detailed pattern classification with subdivisions has piedmont glaciers and, in part , to some small ice been given in a monograph ,“Zoogeography of China” sheets, but there has never been a great ice sheet (Zhang , 1999) . © 1995-2004 Tsinghua Tongfang Optical Disc Co., Ltd. All rights reserved. 2 期 ZHAN G Rong2Zu ( Yong2Zu) : Geological events and mammalian distribution in China 341 Since 1949 , a series of physical regionalization works on both national and local scales has been conducted. So far , the most comprehensive study was completed in 1958 and revised recently by the Working Committee of Physical Regionalization of China , Chinese Academy of Sciences (National Atlas Compilatory Committee 1999 ) . According to this Committee, the three great natural divisions with distinct geological histories respectively , as described above , has been defined. Subsequently, 12 natural zones and 90 natural regions have been identified. Fig. 1 The distribution patterns and their relationship Natural zones have relatively uniform temperature and of land vertebrates of China moisture conditions as well as similar zonal soil and Palaeartic Realm. N : Boreal E : Northeast C: Central Asian vegetation. A natural region has not only uniform P : Highland Indomalayan Realm. H : Hengduan2Himalayan S: zonal features ( climatic , biological , and soil) , but Southern China O : Oriental T : Old World Tropic , island pattern also fairly uniform azonal characteristics ( geological omitted and topographical) . It is equal to“landscape”defined by Russian geographers ( Kysekin 3 , 1960 ) .A 2 Methodology natural unit of region or landscape reflects more fully 211 Geological events the total physico2geographic environment , in which The geological events described above have varied animal habitats occurred repeatedly. already been brought to light by geological and Obviously , it may be to a great extent a reflection of paleogeographical researches and have been