4) Fig. 5 is the extent of the Pleistocene and the present glaciation in China compiled by a Chinese geologist, which suggests general acceptance among Chinese geologists and geographers of the wide spread Pleistocene glaciation throughout the land, particularly in the central and the eastern part of China; the southern border of the past glaciation reached as far as the present subtropical China.
Such a remarkable prevalence of glaciation was first remarked by Lee Szu-kuang in 1930's, when he claimed evidences of glaciation in the lower Yangtze valley, particularly around the hill of Lush an near the Poyang Lake in Kiangsi. His theory was widely disputed but was not generally approved by European scientists. However, it has had a great influence upon the thinking of Chinese scholars and the result is, after the war, a rapid increase in the number of Chinese geologists and geographers in favor of his theory and approval of evidences of glaciation over a wide area.
In the discussion of the Lushan glaciation, Lee suggested three successive glaciations in Pleistocene; the Poyang, the Taku and the Lushan. In the present research of the Pleistocene Epoch in China some geologists added the last glaciation, the Tali; and the Poyang, the Taku, the Lushan and the Tali seems to be an authorized succession of glaciations in the central and the eastern part of China Mainland. The succession and the extent of the past glaciation, however, are not free from criticism even today among Chinese scientists.
5) Articles discussing glaciations in the central and the eastern part of China have been generally appeared in the scientific magazines and reports of geology, rather than of geography. Recently a special publication dealing with the problem was issued (1964), compiled by the Quaternary Era Research Committee in China, containing six articles approving remnants of glaciations in various parts of China. Among them is Lee's article claiming evidences of glaciation in the Western Hills. The Western Hills, Peking's nearest heights, form the western border of the Peking plain, which slopes gently towards the southeast.
Lee's theory is based on the observations of topography and deposits which cannot be explained by other than glaciation, such as linearly arranged basin-like depressions cut into the floor rock of a valley, striated and polished surface produced on the bottom rock, uneven rock surface underlying the Peking plain (Fig. 7), glaciation remnants such as striated boulders, clay-and-boulder deposits which cover deeply the Peking plain. He attributed the la st one to the frequent floods occurred near the end of a glacial period. However, the exact period in Pleistocene during which glaciers flowed down to the foot of the Western Hills is not established.
His discussion goes as far back as the climatic condition under which Peking Man lived. The analysis of pollen, plant and animal remains of the clay-and-boulder deposit; in the Choukoutien Cave by Chinese geologists revealed that the climate of Peking Man's period was rather warm or hot, while the upper and the lower layers of deposits were formed under cold climate. This exemplifies, according to Lee, the existence of at least one interglacial period and two glacial ones.
Other articles contained in the special publication are dealing with glaciations of the Lungmen-Shan in Szechuan, the Great Khingan Mountains, the Tapieh-Shan, the Eastern Tsinling-Shan and the Taihan-Shan. However, a careful analysis and comparison of the evidences and conclusions of these articles reveal some inconsistencies from one another as to the occurrence of glacial periods, the altitude and the extent of glaciations (Table. 2), which suggest the glacial problems in the Pleistocene of China are not yet settled conclusively.

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4) There is a striking difference in the altitude of climatic snowline, which affects the main feeders of the rivers, between the Tien Shan and the Kunlun mountains which are bordering the north and the south of the Tarim basin. In the southern exposures of the Tien Shan the snowline is approximately 4, 000 m and gradually decreases its height until about 3, 500 m in the east part of the mountains, while in the Kunlun it generally stands at 5, 000-5, 500 m and at the great glacier-clad watershed it rises up to nearly 6, 000 m. The change of these altitude is simplified and shown in Fig. 4 (a-b), which represents the climatic profile along the longitudinal zone of 81°-83° E. It generally decreases its height from south to north, however, the inclination grows steeper in the Kunlun mountains and thereafter, while nearing the Tien Shan it becomes gentle. In other words, the rapid decrease in the height of the snowline occurs between the latitudes of 35°-40° N.
Fig. 4 (c-d) is the approximate profile of the snowline during the last Ice Age compiled from the data of F. Machatschek (1912, 1913, 1944), K. Hermes (1955) and H. von Wissmann (1959, 1960, 1961), which is about parallel to the present one. However, the depression was greater in the Kunlun mountains. With the consequence of this, coupled by the development of extensive plateau-like gentle topography of the high altitude as well as the mightier body of the Kunlun itself, can be accounted for the more extensive snowfield during the last Ice Age than in the Tien Shan (Fig. 5). This exemplifies the greater fluctuation in the size of snowfield in the Kunlun mountains than in the Tien Shan when changes of the snowline occurred. And this might be true of the smaller changes of the snowline during historical times, which might have resulted in the greater fluctuation of water of the rivers flowing down the Kunlun mountains.
5) The retreating of glaciers in the Tien Shan and the Kunlun mountains in the last several decades has been observed by many scientists and explorers, which might have generally kept pace with the fluctuations of glaciers of the northern mid-latitude during the last over a hundred years. These fluctuations must have caused the changing of sea-level, as investigated and analysed by S. Thorarinsson (1940) and the eustatic curve for the last 2, 000 years (Fig. 6) was worked by R. W. Fairbridge (1961, 1963). And “historical records over the last two millennia indicate one of the longest sun-spot lows in Roman times, when sea level seems to have dropped to about 2 metres below the present level” (Fairbridge, 1963) is worth noting, because that period roughly corresponded to the Han (Former and Later) dynasties in the history of China, when the silk trade with Rome flourished, and in the Taklamakan desert several ruins such as Niya, Kara-dong, Miran and part of Endere, have been found which were flourishing settlements during the Han period.
To what extent the curve of Fairbridge would apply to the following historical times of this region is a problem, although it seems probable that the extension and the shrinkage of rivers occurred after the Han period, particularly in the southern border of the basin according to the glacial fluctuations of the Kunlun mountains.
6) One way to solve the problem is to examine the Chinese dynastic Annals and other historical records concerning this region and assume the geographical background, particularly dealing with the volume of waters during each dynasty. The weak point is that there were several blank periods, which means the absence of the reliable records caused by the temporary or complete withdrawal of Chinese control from the Tarim basin.

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Recent geographical research in China has, as are exemplified by many articles in Acta Geographica Sinica of recent years, been carried out placing the emphasis upon the studies of natural environment, particularly of climatic factors, of the China's land and of its applied problems. This makes a remarkable contrast with researches before the war, when the majority of topics were concentrated on the problems of historical geography of the land. This change has been probably brought about in many cases in accordance with the national needs of China after “liberation”. Several major problems in which many Chinese geographers are interested can be drawn out from recent articles and publications of geographical research and among them are the glacial problems, past and present.
1) Glacial problems of China were originally discussed mainly by European geographers and geologists concerning the mountainous region of western China and several distinguished views were presented. However, after the war the situation of research has changed. The summary of geographic achievements and the present situation of European geographers and geologists are well expressed by H. von Wissmann in his illustration (Fig. 1) and the following statement.
“In Europa und Nordamerika kann man vielleicht zu Recht von einer pleistozanen ' oder eiszeitlichen ' Schneegrenzdepression sprechen. In Hoch-und Ostasien muss man die letzteiszeitliche Schneegrenzdepression streng von den Schneegrenzdepressionen älterer Eiszeiten auseinanderhalten. Für diese älteren Eiszeiten erscheinen die Unterlagen für eine Zusammenschau noch durchaus nicht zu genügen, zumal wir seit 1949 zu meinem grossen Leidwesen von der chinesischen Wissenschaft noch stärker geschieden sind als von der russischen.” (Die heutige Vergletscherung und Schneegrenze in Hochasien. 1959, s. 227)
2) There appeared several articles in Acta Geographica Sinica and Geologica Sinica of recent years dealing with the problems of glaciation and glacial ages of western China. By tracing remnants of glaciation in the Himalaya (around Mt. Everest), the Tien-Shan and the Chilien Mountains and the Tibetan Plateau, some different views are expressed concerning the ice ages of the past. For instance, some claim the existence of 4 ages, others 3 ages, still others 2 ages, and the last one seems to be the safest conclusion in the present condition of evidences.
Discussions have been concentrated on the relationship between climatic changes during the Pleistocene and the recent crustal movement continued in the mountain zones of western China. The conclusion common to many articles is that the combined effect has contributed much to the development of ice ages and extent of ice-cover. While many geographers agree that the younger the ice ages, the smaller the extent of glacial development (Fig. 2), despite the continual upheaval of mountain lands and that it proves the continual weakening of the invasion of oceanic influences from the Indian Ocean.
3) Remarkable theories were suggested concerning the depression of snowline of the past. A great depression, far greater than estimated by European geographers is assumed (Fig. 3), but the ice age in which such a depression occurred is still obscure. Some hold that it occurred during Qii period -the greatest ice age of the past-, while the other suggests the probability during the last the age.
As to the extent of ice-cover, two opposing views are presented, the one suggests a large extension which covered almost all the land higher than 4, 200 m, while the other claims the different degree of extension according to the patterns of ice-cover, which were determined by both topographical and climatic conditions of the region (Fig. 4).

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