地学雑誌

抄録を表示する抄録を非表示にする

There are many problems still unsolved in the geographical studies of the Silk Road, which in ancient times connected Asia and Europe culturally and materially.
1. Who was the proposer of the name of the Silk Road? Richthofen introduced the term of “Seidenstrassen” in his “China, I”, as well as in the article discussing this route in 1877, and there is no doubt about that Richthofen has popularized the name. The name itself, however, was probably used for the first time in the account of the Greek geographer Marinus of Tyre in about 100 A. D., who had drawn his information from Maes Titianus, a Macedonian silk-merchant who sent agents to China during the 1st century of our era.
2. The study of the Silk Road by Richthofen was very instructive and suggestive, in spite of the time in which it was made when detailed maps of Inner Asia were not prepared and the European translation of the Chinese old annals and records were scarce. Although Richthofen's study had some faults, he had a good command of many important Chinese old annals and predicted many of the geographical problems which have been hottly discussed since the early part of the 20th century, based on discoveries made by the scientific expeditions of Sven Hedin and Aurel Stein.(Fig. 1)
3. The study by Herrmann was scientifically equipped because of the time in which many European translation of the Chinese old annals and records were prepared and some of the results of the scientific expeditions of Inner Asia were published. The weak point of Herrmann's conclusion, however, lies in that he was too confident in the figures of distance of different oasis states from Ch'ang-an and Wu-lei, given by the Former Han Annals.
In ancient times in China, li was not used as one of the official units of distance and was only used as a rough estimate. It was more probable that commonly a day's travel equalled 100li. As a consequence, the assumption of the position of many states and the old road based on the calculation of detailed figures of li of the Former Han Annals was in some parts far from the facts of the past.(Fig. 2)
4. The most reliable routes were obtained by the work of Stein, though it is not free from criticism. In the study of the Silk Road, however, it is desirable to begin with the close investigation of topography and other natural conditions along the road.
Fig. 3 shows the topography and the distribution of settlements and oases scattered along the margin of the Tarim basin, compiled from the maps prepared by the Army Map Service, Corps of Engineers, U. S. Army (1: 1, 000, 000) and the maps of Chinese Turkestan and Kansu surveyed by Aurel Stein (1: 500, 000). A glance at the map shows that the distribution of large oases are confined to the foot of Tien-shan to the north and to the western half of the foot of Kun-lun to the south. The existence of large oases has close relations with the altitude of mountains and the extent of perpetual snow -field. Rivers nourished by large snow-fields flow down the mountains and have built large oases, such as Aku-su, Kucha to the north and Kashgar, Yarkand and Khotan to the west and to the south. The lands are flat and streamlets branch out, showing the character of delta lands rather than alluvial fans. The present highways run connecting those delta -oases and in ancient times the natural conditions were probably not so different from today.
5. Worth noticing, however, is that there scattered many small oases at the apex of the gigantic talus slopes of piedmont gravel, particularly to the southern margin of the basin, attaining in parts a relative height of 1, 500m and more and utterly barren. The path which connects these small talus-apex oases is winding but easy to get water, and even in ancient times it was frequently used as the by-road, particularly between Charchan and Khotan.(Fig. 4)

抄録全体を表示

PDF形式でダウンロード (2309K)

1. In modern climatology, climate is defined by the synthesis of weather while in former times it was expressed by the combination of the climatic elements averaged for a long period. Two important reasons why the mean value does not represent the real state of climate are discussed.
2. Climatology is spatialy divided into four parts; macro-, meso-, local and microclimate. These extensions are considered to be limited horizontally and vertically by certain quantities closely connected with the special types of air flow as shown in the following table:
Horizontal limit Vertical limit Air flow type
Macroclimate >100Km up on tropopause Horizontal motion governed by Coriolis force
Mesoclimate <100Km frictional height (Upper frictional layer) Nearly equal megnitude of frictional and Coriolis force
Local climate<10Km 50-100m (Lower frictional layer) Coriolis force is negligible as compaired to surface friction
Microclimate <100m ca 2m (Bottom layer) Laminar flow

抄録全体を表示

J-STAGEへの登録はこちら（無料）