EN中文

Archive

  • 1965 Volume 31 Issue 2
    Published: 15 April 1965
      
  • Select all
    |
  • ON THE TRENDS OF SUMMER-TIME DROUGHTS AND EXCESSIVE RAINFALL IN THE LOWER YANTZE REGION
    CHIANG TE-LUNG, NIEN TSE-YUAN
    1965, 31(2): 85-99. https://doi.org/10.11821/xb196502001
    Download PDF ( )   Knowledge map   Save
    Based on a chronicle list of droughts, excessive rainfalls and floods (903 B.C.-1909 A.D. ) complied from the materials in classics, chronicles and annals, along with the meteorological records of Shanghai (1875-1962 )，the historical trends of droughts and excessive rainfalls in the Lower Yantze are studied. Using certain intensity cri- terions, the events are classified and return periods are analysed. It appears that there may exist some kind of thousand-year cycles, each with three intervals of different charac- teristics, which show fairly good correspondence with the solar activities. An outlook of the trend in the coming 30-years is made, tentatively.
  • RADIATION BALANCE OF THE "EARTH-ATMOSPHERE" SYSTEM AND THE ATMOSPHERE OVER EAST ASIA
    TSO TA-KANG, CHEN CHIAN-XEI, LI Y?-HAI, CHOU Y躈-HUA
    1965, 31(2): 100-112. https://doi.org/10.11821/xb196502002
    Download PDF ( )   Knowledge map   Save
    The earth's planetary albedo, outgoing radiation and the radiation balance of the "earth-atmos户ere" system and the atmosphere have been calculated by means of mean serological data at 34 stations over East Asia area for June and December during the period 1957 to 1962. In the estimation, some data from aircraft measurement of cloud have been adopted, and Yamamoto's radiation chart has been used in computing in- frayed radiation flux. From the data obtained, some of the characteristic features of the seasonal changes and regional variations of the radiation balance and its components over East Asia are figured out and discussed together with comparisons of these with the lati-rude means of northern hemisphere.
  • INFRARED RADIATION BALANCE IN A CLOUDLESS TROPOSPHERE OVER EAST ASIA
    LI Y?-HAI
    1965, 31(2): 113-128. https://doi.org/10.11821/xb196502003
    Download PDF ( )   Knowledge map   Save
    Based on the aerological climatical data at 34 stations for June and December dur-ing the period 1957 to 1962 and used Yamamoto's radiation chart, the distribution of the infrared radiation fluxs in the troposphere has been computed for a cloudless over East Asia. Besides, the outgoing radiation of the system "earths surface-troposphere" and the mean cooling in the troposphere are given out. It is shown that seasonal and space distribution of the infrared radiation flux is closely associated with monsoon action and topographical characteristics over this area.
  • THE REMOVAL OF THE NATURAL FOREST COVER OF ANCIENT SHAOSHING AND ITS INFLUENCE ON AGRICULTURE
    CHEN CHIAO-YI
    1965, 31(2): 129-141. https://doi.org/10.11821/xb196502004
    Download PDF ( )   Knowledge map   Save
    Ancient Shaoshing had a physical surrounding of rich forest cover. The landscape of its southern part-the Kweichi Hills was a wide subtropical original forest where grew various kinds of Conifers and broad-leaf trees. Its northern part-the Shankwei Plain was a large swamp where grasses grew profusely. In addition to trees and grasses, bamboos grew densely both in the south and the north. Because of human activities, the natural forest of ancient Shaoshing was gradually reduced since the Chunchou(春秋)period. Owing to the increase of population in the East Chin Dynasty(东晋)，the Shankwei Plain was wholly cultivated. Paddy fields appeared everywhere instead of the original grass. At the same time, the Hweichi Hills were also rapidly reclaimed. Tea began to be planted on the hillsides in the Tang Dynasty(唐).Then, mellet, bean, and potato were卜lamed one after another in the Sung(宋)and Ming(明)Dynasty. At last, the forest of the Kweichi Hills was wholly destroyed. The destroying of the natural forest cover had both positive and negative influence on agriculture. On the one hand the people gained cultivated lands and developed the cultivation of this region; on the other hand they destroyed simultaneously the forestry, hunting, livestock breeding and some handicrafts which depended on the forest for raw materials and fuel supply. The worst influence on agriculture was soil erosion. This was the important cause why the flood and drought became more severe since the South Sung Dynasty(南宋).
  • THE SOURCES OF THE DUNE SANDS IN THE REGION EAST OF THE YELLOW RIVER IN NINGHSIA
    HSU CHUN-MTN
    1965, 31(2): 142-156. https://doi.org/10.11821/xb196502005
    Download PDF ( )   Knowledge map   Save
    The total area occupied by sand dunes is about 1050 square kilometers or 5.8％of the investigated. 77.5％of the sand dunes are concentrated in Taolo and Lingwu, ex-tending as continuous belts. While in the other districts, they are only scattered. The extensive Quaternary deposits of varied origin, which are rich in sand, are the primary sources of the sand grains of the dunes. In other words, the sand dunes are formed in situ. This is revealed by the close relationship between the granulometric and morphoscopic characters of the dune sands and that of the nearby quaternary deposits. There axe four basic ways in which the dunes are formed in this region: Firstly, the wind works on the sand grains from the product of the disintegration of bed rocks to form dunes; Secondly, the sand grains, which were deposited abundantly in the dry valley in the wet season are picked up by the wind to form dunes in the dry season; Thirdly, the wind picko up the sand from the recent and ancient alluvial deposits of the Yellow River to form dunes; Fourthly, owing to the improper extension of the cultivated land, the improper grazing or collection of the firewood and medicinal plants, the semi-fixed and fixed sands are turn into drifting sand by the wind.