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    15 December 1988, Volume 7 Issue 4 Previous Issue    Next Issue
    WEAK LINK OF THE RESEARCH ON MODERN GEOMORPHOLOGICAL MAPPING IN CHINA
    Yin Zesheng
    1988, 7 (4):  1-11.  doi: 10.11821/yj1988040001
    Abstract ( 491 )   PDF (2868KB) ( 554 )   Save
    The research on modern geomorphological mapping in China had passed the period of rising and began to be prosperous from 1952 to 1987.This paper selects 317 maps that represent the main achievements in this period and engage in statistios and analysis.Six defects about this research will be discussed as follows.1, Most of the geomorphological maps in China have been compiled without guide of mapping standards, and then,it is difficult for them to make comparison, and it is unfavourable to academic exchange between China and other countries.2, According to the quantity of compiled maps in China,the whole mapping process is divided into four stages.It is abnormal that there is a world of quantitative difference of the gaps for each stage.3, The kind of maps is rather monotonous.Maps with middle and small scales and general maps are relatively more, while maps on large scale and other kind of maps.such as applied, dynamic and genetical ones etc.are only a few.4, The mapped regions are unequilibrium.Some provinces, for example, Hebei, Hunan, Shangdong and Inner Monogolia, etc., and regions, such as the Middle and Lower Changjiang River, the Loess Plateau are very active in mapping.Others, for example, the Tibetan Plateau, are not.5, The research of endogenic agency in geomorphological classification is weak.There is a larger gap between China and other countries, They always pay more attention to that field.Therefore, it is comparatively weak in the theoretical base of the research work on geomorphological mapping in China.6, In the research on the pattern of the geomorphological maps and the expression, the mapping of composite pattern that is very popular in the world is not widespread in China, the expression of most of our maps is rather dull.
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    GENESIS AND RESEARCH SIGNIFICANCE OF THE PLINTHITIC HORIZON
    Zhu Jingjiao
    1988, 7 (4):  12-20.  doi: 10.11821/yj1988040002
    Abstract ( 1887 )   PDF (692KB) ( 1084 )   Save
    Plinthitic horizon in mid-lower reaches of the Yangtze River in China is an index bed of Middle Pleistocene, which, developed commonly in the lower parts of the alluvium, eluvium, cliff debris or diluvium.It has irregulat plinthitic textures with red alternating in grey.white, yellow and brown.The red color and the nets of the plinthitic horizon are not original.but a result of a long-term leaehing and weathering under the conditions of humid and warm climate during middle Pleistocene.The results of chemical complete analysis and clay mineral analysis suggest that the leaching degree of plinthitic horizon is very similar to red soil but a little weaker than that of laterite, the clay mineral components of red clay and white clay are the same, while the iron content of them is dif ferent.Theref ore, the plinthitic horizon is resulted from the reduction and migration of three-valance iron.The distribution of the plinthitic horizon is strictly controlled by the fossil landform and altitude.The much more humid and warmer climate at that time.the flat topography as well as the frequent movement of the groundwater are absolutely necessary conditions to form the plinthitic horizon.The research on it has two specific meanings.First, the fact that the plinthitic horizon has experienced stronger shift since it formed, will provide valuable informations for the amplitude and character of the tectogenesis in South China since Middle Pleistocene.Second, the plinthitic horizon can not be developed in the precipitous hilly areas like Lushan Mountains, this is also a very good evidence for solving the problem whether or not some glaciations have taken place in East China during the Quaterary period.
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    VERTICAL DIFFERENCE AND GEOCHEMICAL LAYER CHARACTERISTICS OF HEAVY METALS DISTRIBUTION IN THE SOIL OF GEOGRAPHICAL LANDSCAPES OF SOUTH GUANGDONG
    Hong Jihua, Zhang Shen
    1988, 7 (4):  21-31.  doi: 10.11821/yj1988040003
    Abstract ( 574 )   PDF (639KB) ( 523 )   Save
    The vertical difference of the distribution of heavy metals and their geochemical layer characteristics including Fe, Mn, Co, Ni, Zn and Pb in the soils of the Tropics and the Subtropics have been studied in this pape.The difference is reflected by the distribution in five forms including water-dissoved, exchangeable, organicbound, Fe-Mn oxide-bound and residual.There is a layered Characteristic of the form distribution of heavy metals in the soil.The concentrations of water-dissolved, exchangeable and organicbound heavy metals descend from the upper layer to the lower layer in the soil profiles.The distribution of water-dissolved and organicbound metals is consistent with the organic matter, and is contrary to the pH valve.The distribution of Fe-Mn oxide-bound metals is consistent with the clay particle.The distribution difference of the residual metal in every profile is very little.The order of potential mobility of heavy metals in the soila of geographical landscapes of the Tropics and the Subtropics is as follows.Fe>Mn>Pb>Cu>Zn>Co.
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    THE FORMATION AND EVOLUTION OF THE XIANG HU(LAKE) AND THE PROSPECTS IN ITS DEVELOPMENT
    How Weilin
    1988, 7 (4):  32-39.  doi: 10.11821/yj1988040004
    Abstract ( 947 )   PDF (619KB) ( 490 )   Save
    Situated in the west of Xiaoshan County, Zhejiang Provinc, the Xiang Hu, a famous lake in the Ningho-Shaoxing Plains, has as its predecessor the Xicheng Hu.originally a layoon, filled up under the combined work of both nature and man.In the Secondyear of the reign of Zhenghe in the Northern Song Dynasty (1112A.D.), under the specific geographic circumstances, a lake was restored by turning the former fields into a lake, and this artificial lake was known as the Xiang Hu.During the eight centuries and more from the end of the Northern Song Dynasty to the Republic of China, Sharp conflicts continued between those who maintained to drain and those to preserve the lake A certain dimensions of the lake, however, survive as a result ofthe need in agriculture though the lake, like many of its counterparts, has experienced a series of the processes of natural evolution-from a lake, the marshes to the land.In the 1920's, as reclamation activities went on in an ever increasing pace, the waters of the Xiang Hu narrowed gradually.Since the large-scale construction of water conservancy works undertaken by Xiaoshan County since 1949 took over the irrigation function of the lake, it became a necessary trend to reclaim cultivable land from the lake by building bunds.Thus the Xiang Hu is reduced from an immense water bony of 37,002 mu of its original size to the present riverslieped lake with a mere reduced area of 1,460 mu.On the other hand, owing to its mavellous character suitable for brickmaking, the clay of the lake was exploitsd in as early as the Mig Dynasty in handicraft industry to make bricks aad tiled, the unprecedented enlargement of the brick and tile market since the establishment of New China has greatly sped up the industry, which, through its effective digging, has led to the reappearance of a wide expanse of waters from the former dying.lake.Once again enlarged, the Xiang Hu provides excellent conditions from the development of touristry and in addition, an uncommon example for the transformation of lakes in the Ningbo-Shaoxing Plains.
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    THE CHANGES OF DALAINOR LAKE
    Guo Zhaoshan
    1988, 7 (4):  40-47.  doi: 10.11821/yj1988040005
    Abstract ( 667 )   PDF (605KB) ( 515 )   Save
    The studied region is situted at the westernbor der of Chifeng city, with its south western part bordering the city.Its location is about 116°26/-117°15'E and 43°30'-42°40/N, in the northwest of the region, The surface of the lake approximates 1226m a.s.l.with an east-west width of 15 km and a length of 21km, covering an area of 225km2.The depth of it is geverally 10m, and the deepest place 13m.Dalainuoer (Dalainor) is located in the most developed part of the compossion rift belt of Xilamuleng River at the old lake region.Its is a structural lake.At the beginning of Tertiary period it was a part of the lake sea ia Nei-Menggu (Inner-Mongol) Plateau At the middle Pleistocene, the Jake was formed near Haoluku, with an area about 8% of the whole region, and at the end of Middle Pleistocene, it enlarged to half of the (river source) basin.At Middle late Pleistocene the lake covered a large part at both sides the of present divide at the end of Plei-socene, it overflowed across the present divide to the whole region and even beyond the studied region.That was the most flourishing period of the lake.At Holocene earthcrust consistently uplifted, while the lake shrank to the present depression situated west of the divide and north of Daerhan There are five rivers such as Kang alkula Piiver and others flowing into the lake, forming a centripetal inland drainage.At the beginning and late periods of Middle and late Pleistocene, the earthcrust of the region relatively uplifted, which caused the lake water to dissipate, mainly to dry up.From early Pleistocene to Holocene, the lake water appeared four times and disappeared four times.Thus the lacustrine and fluvial deposits left in the region have a thickness of 150-200m rich in ground water resources.
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    CHANGE AND TREND OF DEVELOPMENT OF STREAMFLOW AND SEDIMENT IN THE REACH BETWEEN HEKOUZHEN AND LONGMEN OF THE YELLOW RIVER
    Zhang Shengli
    1988, 7 (4):  48-53.  doi: 10.11821/yj1988040006
    Abstract ( 652 )   PDF (458KB) ( 447 )   Save
    The reach between Hekouzhen and Longmen of the Yellow River is the source area of high and coarse sediment of the YeJlow River and its amount of streamflow and sediment on the siltation of the lower Yellow River are very important.In this paper, the change of streamflow and sediment of that reach in recent years is analysed, the reasons of change are studied,the trend of development in the future is predicted.In recent years, runoff and sediment in the studied reach are reduced obriously, and the ratio of reduction in the flood period is bigger.The main reason is the reduction of the amount and intensity of the rainfall.Comprehensive controlling measures have intercepted role.Drawing off water and sediment, deposited on the streambed have also some effects.In the future, the change of streamflow and sediment regime in the reach between.Hekouzhen and Longmen will be "polarization" further, i.e., the streamflow and sediment in the common years will be reducted, if rainstorm occurs, the flood and the sediment may be greatly increased, and the change depends on different combination of such factors.
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    ANALYSIS OF THE SELECTED LINES OF A CANAL CROSSING THE WATER-SHED BETWEEN THE QIANTANGJIANG RIVER OK ZHEJIANG PROVINCE AND THE XINJIANG RIVER OF JIANGXI PROVINCE
    Zhu Yongkang, Wang Zongtao, Zhao Luojin, Wang Chengnong, Zhang Fuxiang
    1988, 7 (4):  54-63.  doi: 10.11821/yj1988040007
    Abstract ( 693 )   PDF (714KB) ( 441 )   Save
    According to the relationship between the linking of an interfluve of two Rivers and a network of stream system, this paper analyzes the significance of the canal crossing the watershed between the Qiantangjiang River of Zhejiang and the Xinjiang River of Jiangxi.Then, the physiographic conditions in the selected area are discussed as fallows.1.Topographically, according to the principle that the relief must be low and the selected line must be short, there are there lines to be selected in the water-shed area between the Qiantangjiang River and the Xinjiang River i.e.the North Line, the Centre Line and the south Line, in which the canal of the North Line will be 45km long and 1025m high, the Centre Line 46km long and 96.86m high, and the South Line 35km long and 105.8m high.2.According to the engineering geological conditions it seems that the Centre Line is best, the North Line is second, and the South Line is bad.3.As for the form of the canal, it should be taken as areservior shape of river channel.For its water sources, apart from using small reservoir built along the canal, it is necessary in addition to develop such as drainage area of the Jinshaxi and Shangshangang,or Jiangshangang, and to build or extend some keserrvoirs, i.e."Giy1" and " Jixi", or "Baishuikeng" Reservoirs, and so on.Las, taccording to united scheme of the stair channel of the two rivers, three distinct schemes (including the linking-up opposite each other of both the beginning point and the end poin,tthe contour penetration, and many stairs of the Centre Line).are proposed.It is considered that in them the scheme of linking-up opposite each other of both the beginning point and the end point in the Centre Line is more reasonable through synthetic comparisoni, i.e.investment, moving hereafter, and engineering construction compavisons.
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    CLIMATIC CHANGES OF DROUGHT-WET IN XIAN REGION OF CHINA DURING THE LAST 1604 YEARS
    Li Zhaoyuan, Li Li, Quan Xiaowei
    1988, 7 (4):  64-69.  doi: 10.11821/yj1988040008
    Abstract ( 524 )   PDF (403KB) ( 457 )   Save
    According to the historic records of Xian region, a climatic series of drought-wet indices of this region for the last 1604 years was reconstructed.By method of optimum classification (classifying by statistic variances), power spectrum analysis, and harmonic analysis, some characteristics of the drought-wet climate in Xian and its relationships with those in other places on the northern hemisphere were explored.The climatic change of drought-rainfall in Xian can be divided into six periods.Ⅰ.380-680 A.D., dry.Ⅱ.690-990, wet.Ⅲ.1000-1220, dry.Ⅳ.1230-1410, wet.Ⅴ.1420-1630, dry.Ⅵ.1640-now, wet.On the secondary time scale of about a century, the drought-wet climate in Xian may be divided into 18 episodes, each of which ranged about 89 years on average.There were three rather dry episodes respectively in 460-500, 1140-1220, 1420-1490, and several wet episodes appeared in 690-750, 1230-1250, 1380-1410, 1640-170., 1810-now.Since 380 A.D.the duration of the dry periods has become shorter and the latest wet period of these two time scales are the longest of all.By calculating the ratio of dry or wet years during each period, we discovered that even in the, wet periods in Xian, dry years still occurred frequently.The result of hammonic analysis to the drought-rainfall series, climate in Xian varied, on the background of changing with the period of about 520 years, with the notable periods of 71-75 years.The statistical correlations of the wet/dry climatic indices series between Xian and other places show results similar to those obtained from the study on atmospheric circulation.
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    DYNAMIC SIMULATION OF THE AGRICULTURAL PRODUCTION SYSTEM IN HUINAN COUNTY
    Yu Side
    1988, 7 (4):  70-77.  doi: 10.11821/yj1988040009
    Abstract ( 450 )   PDF (574KB) ( 417 )   Save
    In order to establish a stable and high-efficient agricultural production system (APS) in Huinan county, and to control the dynamic behaviour in the future, this paper, analyzes first the physical conditions and the problems of the APS in the present time, and then establishes the longterm and dynamic development model of the APS with the theory and method of system dynamicsThe following points are defined through studies.1).The agricultural resourses of the APS in Huinan county are very rich, but they are not utilized fully and effectively.There are still a lot of problems in the APS, and the present decision of agriculture is not satisfactory for the APS.2).In the future, the first important task is to raise the economic effect of the APS, and pay much attention to both ecologic effect and social effect.According to the analysis of the simulation results, the "Comprehensive Development Plan" is the best play for the APS in Huinan county.
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    THE STUDIES OF AGE DETERMINATIONS BY ESR METHOD
    Peng Zicheng, Liang Renyou, Jin Sizhao, Huang Peihua, Quan Yucai
    1988, 7 (4):  78-82.  doi: 10.11821/yj1988040010
    Abstract ( 525 )   PDF (346KB) ( 655 )   Save
    ESR dating, suited for the Quaternary samples, has been developed abroad in recent decade.The determinations of deer horn, lamprotula, stalagmite, loess, coral and shell samples by ESR dating hawe been described in this paper.The ESR age of deer horn from Xianshui River and lamprotula from Nihe-wan are 1,25 and 1.22-1,37×106 yrs,respectively, which are concordant with that of their stratigraphy.The average of the ESR age of the stalagmite from the fourth place cave of Choukoutien is 6×104yrs, which is close to 6.5×104 yrs of the 230Th/234U age.The ESR age of the loess from S-7 layer of Luochuan profile is 7.38×105yrs corresponding to that by thermoluminescence and paleo-magnetic methods.The ESR age of the coral at South Sea is 4.09±0.61 dropped in the range of 5.0±0.2 and 3.75±0.19 ka by 230Th/234U and 14C methods, respectively, uhile much near to the 14C age.The ESR age of the shell at Baoyu island is 1.66±0.25 ka, which concords with 1.69±0.09 Ka of the 14C age.The ESR age determinations as mentioned above show that the method of ESR dating will be a powerful tool of the studies on the Quaternary chronology.
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