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  • 1987 Volume 7 Issue 4
    Published: 20 July 1987
      
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  • ENVIRONMENTAL CHANGES IN EASTERN CHINA DURING THE LATE PLEISTOCENE
    Yang Dayuan, Feng Wenke, Zhao Xitao
    1987, 7(4): 297-305. https://doi.org/10.13249/j.cnki.sgs.1987.04.297
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    The paleo-environmental changes during the late Pleistocene either in northern and southern parts, or in lands and seas of eastern China, were mostly non-synchronous. The oldest event of low temperature occurred during the Last interglacial period in the northern part of the South China Sea. The transitional period prior to the last glaciation came about in the northern part of eastern China about 115 ka ago. The desert environments of the inland of the northern China were developed both in the glacial maximum and in the warm interglacial period, but the loess accumulations mostly took place, during the glacial period. The sand dunes and the periglacial solifluctions in the lo wer Changjiang River region were formed during the last glacial period. Com paring the oxygen isotope curve with the paleo-temperature curve from the northern South China Ses, as well as the transgression-regression alignment from the southern Huanghai Sea, they are partly non-coordinate. The phenomena mentioned above were the result from following reasons that the paleo-environmental changes in eastern China were controlled by common factors leading to changes of worldwide environment, on the other hand, the different changes were related to the special geographical position, the topographic conditions and the monsoon circulation of east Asia as well as time lag required by adjusting process of varied changes themselves.
  • PHYSIOGRAPHIC STUDY OF LUSHAN
    Li Jijun, Zhu Junjie
    1987, 7(4): 306-315. https://doi.org/10.13249/j.cnki.sgs.1987.04.306
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    Three fault cliffs identified clearly on both sides of Lushan show that Lushan experienced three times of intensive block-fault uplifting during Pliocene-Pleistocene period. Consequently, two piedmont trepen with typical features of pediment, now preserved as flat-topped ridges, were formed under subtropic and tropic environment. Deep chemical weathering prevailed at that time and “double surfaces of levelling”s (Budel) developed. In the authors’opinion, it seems that the suggestion of C. R. Twidale which the debris co vered pediment can not develop or at least survive in the humid tropics is unable to be adapted to the case of Lushan completely. Based on the data of paleomagnetic dating collected in recent years, the authors suggest that the Jiujiang gravels were deposited in the early Pleistocene, and the vermiculated red soil with the basal gravels were mostly plinthtic in the middle Plaistocine. Along the banks of the Changjiang River the vermiculated red soil always occurred as continued sidimentary sequence of flood-plain facies, whereas those on the piedment area of Luahan were commonly punctuated by many sedimentary gaps. We have found six sedimentary cyles in the sections of the plinthtic red soil. Among them the lower triplex is dark red in colour with iron pans or honeycomb structure, while the upper triplex is rather pale, has not iron pan and often stained by ferro-manganese coating. Sometimes the upper triplex of the plinthtic red soil constitutes a mantle of low terrace (T2) with a weathered basal gravel underlain beneath. It shows that the upper triplex means not only sedimentary regime but also geomorphologic development of Lushan. After that Hsiashu loess deposited, which can be diveded into two parts. The upper part of Hsiashu loess was surely formed in the main Wurm stage. Evidences obtained in recent years show that there are plenty of morphologic and sedimentary relics created under hot and humid climate and no glacial phenomena had been found in Lushan, area.
  • A PRIMARY STUDY OF AGRICULTURAL DROUGHT IN THE LOESS PLATEAU AREA
    Kan Guisheng, Sun Ronqian, Geng Leihua
    1987, 7(4): 316-325. https://doi.org/10.13249/j.cnki.sgs.1987.04.316
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    The dry-day sequences (days) and number of wet-days in a year and growing seasons (April to September) are used to analyse the relations between precipitation and agricultural drought without irrigated condition, and the characteristics of annual drought variations and variations in a year in the Loess Plateau area, The significative result is obtained. In addition, the run theory is used to study drought, probability equation p= pK-1(1-p) is derived from the probability mass function of run-length f(k)= qpK-1, in which P is the probability of obtaining a sequence of k-day dry-days and p is the distribution parameters and also the conditional probability of a dry-day following a dry-day. It can be obtained from the observed data and the following equation where s1 is the total number of dry-day sequences of various lengths. Both of P and p show the stochastic characteristics of drought and distinct regional objective law of distribution in the Loess Plateau area.
  • ON THE COMPREHENSIVE DEVELOPMENT OF THE SPECIAL ECONOMIC ZONE IN XIAMEN
    Yao Shimou, Xu Guiqing, Ye Feng, Zhang Lisheng, Hu Xinyun
    1987, 7(4): 326-337. https://doi.org/10.13249/j.cnki.sgs.1987.04.326
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    Xiamcn is an important coastal harbour and tourist city.Since the establishment of the spccial economic zone in 1980, great development in economy and urban construction have taken place.The built-up area has expanded to 38km2 and the population has increased to 362 000 in 1986.But the figures will rocket to 1510.7km2 and 1.04 million if the whole urban area (including Tongan county) is taken into consideration.The urban spatial structure will be, as Prof.Wu Liangyong suggests, one center and six Satellite towns around.The integratcd development is most important to Xiamen’s future.The stratigic position of Xiamcn can be analysed in four aspccts:favoriate geographic location, high level of economic opening to the outside, close relatio- nship with Xiamen-Zhangzhou-quanzhou economic area, and the harbour with favorite coast.Advantagious and disadvantagious factors should be carefully studied in the process of defining the comprehensive developing strategy.The paper suggests that the integrated development could he divided into three levels.Xiamen special economic zone should play the role of central city in the south Fujian Province.According to our research, the population of Xiamen will increase to 550000-600000 by 2000 (in built-up area), and the urban area will expand to 45-55km2 by 2000, including suburb satellite industrial towns.As the relations of urban arrangements with regional economy, especially those in the following respects,are so complicate with each other, they should be dealt with carefully:1.To handle carefully the relation between urban and regional economic development of Xiamen.2.A set of natural, geographical, social, economic, political and administrative factors have commonly influenced the pattern and strength of urbanregional relationship.3.To deal better with the urban nature and scale and function of the development of each city or town in its regional system.
  • AN APPROACH TO THE CHARACTERISTICS, GENESIS AND PALAEOGEOGRAPHICL ENVIRONMENT OF XIALU BURIED PEAT IN GUANGDONG PROVINCE
    Wan Enpu, Wang Manhua, Ma Xuehui
    1987, 7(4): 338-347. https://doi.org/10.13249/j.cnki.sgs.1987.04.338
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    Xialu peat in Suixi county, Guangdong Province, is the well-preserved and shallow buried peat which is found in the seashore zone of south China, characterized by thick peat layer, large reserves and earlier peat-forming period. It mostly belongs to woody peat, with higher carbonization, benzenbitumen, humie acid and oil contents, having certain industrial value. On the other hand, the peat contains high ash, low cellulose, hemicellulose and nitrogen. According tostratum and sporo-pollen analysis, the.peat accumulation process can be divided into 3 sedimcntal cycles, and each cycle began from the semiment of rotten wood. Geologically, each cycle began in the period of transgression when vegetation disappeared. Xialu peat formed in 60000-30000 yr. B.P.Because crust subsidence and accumulation rate of organic residues were in balanced state in the process of peat formation, the hugely thick:peat basin was formed.
  • THE SPECTRAL ENERGY OF THE SOLAR DIRECT RADIATION IN BEIJING
    Zhou Yunhua
    1987, 7(4): 348-357. https://doi.org/10.13249/j.cnki.sgs.1987.04.348
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    By means of thermoelectric Actinometer mounted with eight coloured glass filters, the spectral irradiance of the solar direct radiation were measured in Beijing during 1977-1978 and 1983-1984. Based on 1423 series of data obtained from the observations, the effect of the solar elevation, observation time and seasons as well as aerosol and water vapor on the spectral irradiance are analysed. The observation results were also compared with that obtained in the Qingzang Plateau. Finally, the cmpirical formulas which have been proposed by the author for estimating ultraviolet and visible direct radiation are examined by using all observation data. The result is very satisfactory.
  • PREDICTION OF RADIONUCLIDE INVENTORY FOR SEDIMENT IN LAKE GREIFEN(SWITZERLAND)
    Wan Guojiang, Santschi P. H.
    1987, 7(4): 358-363. https://doi.org/10.13249/j.cnki.sgs.1987.04.358
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    Comparing the radionuclide inventories of sediment (90Sr,137Cs,230,240Pu,2,0Pbex,7Be) with the inventories expected from atmospheric fallout records, we find that the ratios are between 0.38-1.3 in the sediment core GR-83-11 of Lake Greifen. On the basis of the erosion in drainage basin and of the retention in laker a model is made from measured quantities to predict the radionuclide inventory ratio in this paper. The best agreements between calculated and observed inventories were obtained for the nuclides. For the calculated error. we would easily be explained by different mechanism of additional removal for individual nuclide.
  • THE ENVIRONMENTAL BACKGROUND VALUES OF REE, U AND Th IN SOILS OF THE SONGLIAO PLAIN
    Wang Yuqi, Sun Jingxin, Tu Shude, Zhang Yuanji
    1987, 7(4): 364-368. https://doi.org/10.13249/j.cnki.sgs.1987.04.364
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    In this paper, the contents of REE (La, Ce, Nd, Sm, Eu, Tb, Yb and Lu),U and Th in the soils of the Songliao Plain were determined by NAA. The types of frequency distribution of concentrations for these elements were tested. The background values of 8 REE, U and Th were given.In addition, the concentrations and distribution characteristics of REE, U and Th in diff crent types of soil in this area have been also discussed.These soils are black soft, chernozem, meadow soil, brown earth, dark soft, chestnut soft, dark brown earth and lessive. The results obtained show that the contents of 8 REE, U and Th in soils of the Songliao Plain are generally close to those of world’s soil. The average value of the total REE in soil of this area is 172 ppm. The standard deviation is ±19.6 ppm and the coefficient of variation is 0.114. After normalized by mean values of chondrite, the REE patterns for different main group soils are very similar to each other, as well as to those of typical North America shales, all with negative slopes. The background values of U and Th in this area are 2.34 and 1.08 ppm, respectively. These values are also close to those of world’s soil and the average abundance of the crust. The ratio of Th and U is 4.6.
  • THE ANALYSIS OF COLOUR INFRARED IMAGES OF SOIL NUTRIENT IN THE HUANGHUAIHAI PLAIN
    Li Tianshun
    1987, 7(4): 369-373. https://doi.org/10.13249/j.cnki.sgs.1987.04.369
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    The analysis of colour infrared images shows that these four factors:soil texture, wheat community exterior in the early jointing stage, the distance of crop land from villages and communication lines,and farmland utilization features,have definite interpretation elements, And they are obviously correlated with soil nutrient, The rank of the four factors in soil nutrient is that the first is the soil texture, the second the wheat community exterior, the third the distance of crop land from villages and communication lines,and the last the farmland utilization features. Through comprehensive judgement by the arthmetic progression mark, the soil nutrient is classified into three grades of high, medium and low.
  • CHARACTERISTICS OF SEDIMENTS IN SEASHORE SALT MARSHES
    Yang Shilun
    1987, 7(4): 374-382. https://doi.org/10.13249/j.cnki.sgs.1987.04.374
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    Based on the analysis of samples collected from the coast of north Jiangsu Province and Shanghai from July to November 1985, the characteristics of the sediments both in salt marshes and ncarby bare flats are discussed. From sea to shore, the characteristics are as follows:1.Usually, mean grain size becomes small and the standard deviation becomes big except in erodent coast, and the coast where vegetation density becomes rare towards the bank. 2.Salinity and the content of organic matter get greater, while pH value gets smaller. 3.The content of heavy minerals increasc mainly because of the increase of mica. 4.The content of spore-pollen increases.In, salt marshes, pollen of herbs is domenant, 5.The number of Foraminifera decreases.