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  • 1985 Volume 4 Issue 1
    Published: 15 March 1985
      

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  • Dong Guangrong, Gao Shangyu, Li Baosheng, Wu Zheng
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    At the present time two kinds of fossil ice margins have been found, con-gelifolds and fossils sand (loess) wedges in the strata of the studied area. The former is mainly found in the limnetic strata at the top of the Salawusu Group(Q31), The middle Chengchuan Group (Q32-2), The middle and the lower Dagouwan Group (Q43) and at the bottom of Dishaogouwan Group (Q43) along the Salawusu He in the southeastern depression Among them the middle Chengchuan Group is the largest and the widest.Besider, it can also be found in certain horizons along the wuding He, Lu He, Hailuitu He, yulin He and Salawusu He near the loess hilly areas. The latter is mainly presented in the Tertiary mud stone or red earth, in the lower-middle Pleistocene loess or the lower part of the late Pleistocene sand (earth) gravel layer and on the top of the middle Chengchuan Group in the central-western dry denuded upland and the flat and lower areas on the low ridge land of its extending part to the depression.According to the morphological characteristics of the profile, these folds and wedges had not any relation to the genesis of tectonic movement fluvial-erosion, accumulation, glacier, mudflow, hard press of landslide and drying crack of ground surface, but to the stratum deformation or disturbance caused by seasonal nonhomogeneous melting and freezing processes for a long time in the frozen eartn area.The big or medium type of nondeveloped congeli-folds (mainly situated in the upper late pleistocene strata) and sand (loess) wedges(situated in the middle and lower profile)were related to the seasonal process of the permafrost and the other congelifolds located in the middle and lower Holocene strata and the small type of sand (loess) wedges located in the upper profile might possibly be formed under the condition of the deep seasonal frozen earth and even the other year's frozen earth.
  • Chen Yongshen, Li Kerang, Sha Wanying
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    To estimate the total heating intensity transported upwards from the sea surface to atmosphere over the Northwest Pacific ocean, the authors employed the following formula.Qa=QLE±QH+QEF where Q, denotes the total heating intensity, QLE the latent heat of evaporation QH the sensible heat exchange and QEF the effective longwave radiation.Results indicate that the largest center of the Qa occurs over the Kuro-shio warm current but not coincides with the largest absorbed radiation. The values of the annual tolal heating intensity was mainly determined in winter and autumn. A large proportion of the surplus solar energy absorbed at the sea surface during sumer is stored by the oceans, and is released to the atmosphere during the colder seasons when there is a deficiency in solar energy. By the same mechanism much of the solar energy absorbed at the low latitudes is transported by ocean currents and released to the atmosphere at the higher latitues where receipt of solar energy is also comparatively deficient.
  • Zuo Dakaug, Xu Yuexiau, Chen Deliang
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    According to the observed data of water consumption (E) of the main crops in the prefectures of Shijiazhuang, Xinxiang and Dezhou and in Beijing, evapotranspiration coeffcient of crops (a) in Penman's formula is determined by calculating evaporativity from the water surface (E0) :a=0.78 for winter wheat, a=0.72 for cotton and a=0.78 for corn. A formula, E=aE0, is adopted to estimate water consumption of the crops in their growing pariod in the low plain of Hebei province. The estimated water consumption is as follows; 400-470 nim for wheat;613-708 mm for cotton and 350-405 mm for corn.In successive rotation of wheat and corn, an annual amount of water deficit in wheat field is about 242 mm, while in monoculturellt, It is reduced approximately to 164 mm. water deficit for one-crop farming of cotton and corn amounts to 107 mm and 39 mm respectively.water deficit for winter wheat in Cangzhou and the eastern part of Lang-fang exceeds 180 mm, while it is decreased to less than 140 mm in Handan and southern Xingtai. The areas seriously suffered from water shortage are located in southern Changzhou and the western part of Xintai and Hengshui. As for the areas of Wenan Dacheng and Qingxian Counties, water deficit becomes less serious.From April to May is a period of the highest water consumption of wheat and the sowing time of cotton and other spring sowing crops. But in this period precipitation is the lowest. Therefore, a complementary amount of water is required in irrigation.
  • Li Ribang, Tan Jianan, Wang Lizhen, Zheng Daxian, Wang Wuyi
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    The features of the geographical distribution of fluoride in the cultivated soil and the relation between these features and endemic fluorosis were expounded in this paper. The total fluoride in the cultivated soil is mainly affected by the bed rock, or the original rock forming the cultivated soil, so the total fluoride in the cultivated soil in the distribution area of rock and mineral which are rich in fluoride is high. There is an obvious zonality in the geographical distribution of dissoluble fluoride in cultivated soil, it is low in torrid zone and semitorrid zone, most of them are less than 1 ppm; but it is high in arid and semi-arid region of temperate zone and semi-temperate zone, most of them ane more than 2 PPm. The effect of both the total fluoride and dissoluble fluoride in the cutivated soil on the fluoride content in food crops is not obious, however there is a close relation between the dissoluble fluoride in the cultivated soil and fluoride in shallow ground water.Thus the effect of cultivated soil on human body for resulting in fluo-orosis is by way of the affecting fluoride in shallow ground water which is used as the source of the drink water.
  • Geng Kaunhong
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    This paper is a summary of the accumulation of sand along the front of shelter belt of the railway and its experiment of prevention and cure.It is a region from southeast K905 to northwest K909 of the railway on gobi west of Yumen town. It is located in the alternative region of the west and east wind, but the west wind is stronger and it prevails longer. On the left of the railway there is broad gobi with soil, and at the far west there is the former wood belt from south to north but it breaks and leaves a gap toward the west (west wind gap) near the railway. Outside the gap is a mobile survived mound of soil erosion and a sand drift. Therefore, the sand accumulates only along the wood belt at the left front of the railway, and the western section is more serious than the eastern one. The east wind can restrict the sand accumulation but can't stop its intrusion to the wood belt.The accumulation of sand is caused by the sand wind stopped by the wood, and the wind velocity near the surface decreases fast. However, to keep the wood growing this wood belt must be often irrigated. The sand accumulation makes great damages, because it destroys the shelter belt and approaches to the railway, a threast to the trasportation. So it must be prevented and cured, and emphsis must be put on the sand accumulation of the western section. The plan of prevention and cure is as a whole made of two steps, that is to block the west gap and to withdraw the sand.The former step is to keep the west section of this belt in good condition to extend it to K900-500, and to build two wood belts to block the west gap. Before the wood belt on the west side must be established on area of solid sand barrier, ditch and dike of sand prevention, and the bush belt. After it is established, it prevents the sand intrusion to the wood belt. Unfortunately, according to the investigation of 1976, this prevention and protection area has been detroyed, and the sand drift has instruded to the wood belt. It is necessary to reestablish the area of prevention and protection.
  • Gao Shanming
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    The Luan River is a medium-size river carrying heavy sedimentary load.Its water flow and sediments mainiy come from the mountainous regions of Yan-shan Mts.Controlled by the tectonic fault, the middle reaches of the Luan River change its course and form branches. Since Quaternary the course of the Luan river in Qianxi Bend has branched into the Late and the Middle-Early pleistocene alluvial fan systems in the east and the west of tangshan town.The eastern fan formed in the late pleistocene is a larger one which can be divided into three areas. The proximal area stretches right to the mountainous mouth; the mid-fan area is in the south of Zhaocun (where there are many ero-sional surfaces and lag sediments of the river in the stratum.It shows that the hydraulic conditions of scouring and silting have greatly changed their courses, The distal area where the deposited debris transforms to finer grains and stratigraphic series tends to be in Steady state, is situated in the south of Dingliuhe. Marine stratum is found on the lower plain in the south of Yangge-zhuan and there the sedimentary facies changed from alluvial-pluvial to alluvial-marine deposits.In the formation period of the alluvial fans, the sedimentary environments hand involved time and again fluctuations of the climate.The semi-arid climate is the most favuorable condition to develop alluvial fans, because in this period the rate of sediment deposition is very fast.
  • Lin Zhiguang, Li Yingjiang
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    1.There is a typical phenomenon of mountain-valley breeze in Tianchi. The direction of the moutain breeze is southeast, and the valley breeze northwest, the frequency of mountain breeze is the largest in winter and that of the valley breeze in May and June.2.The velocity of mountain breeze is larger than the valley breeze, this phenomenon is abnormal.3.There are two transitional periods between mountain and valley breezes. The time of occurence of them has a seasonal change, the time of the transitional period from mountain to valley breeze is about three hours later than the sunrise, but from valley to mountain breeze, a little earlier than the sunset.4. The days of mountain-valley breeze in summer is more than in winter.5. After the time of the transitional period (from mountain to valley breeze), the air temperature increses 2-6℃ and the relative humidity decreses 10-20% suddenly; and from valley to mountain breeze, the air temperature decreses 2-4℃, ley, to mountain breeze,the air temperature decrese 2-4℃, and the relative humidity increses 15-25% suddenly.6.The wind velocity of mountain valley breeze changes with diurnal range of air temperature, the larger the diurnal range, the larger the wind velocity.
  • Wang Ling
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    The southern part of Hengduan Mountains is a region of the highest latitude and the highest altitude that the northward shifting rubber trees successfully grow in China.In winter, the rubber-growing regions of the Hengduan Mountains are under the control of Indian continental dry-warm air mass with prevailing west wind. The weather is clear and the temperature is higher, since the Ailao Mountain, Wuliang Mountain and Nu Mountain protects the tropical plants from damages of the north cold air.Another characteristic is the great range of the vertical variation in height and also in climate. Under 1000 metres above sea level, the minimum temperature of the wintry clear night rises with the height, and an inversion layer is formed. The rubber trees grow at 700-1000 metres above sea level, which is called thermal belts on slopes. Under 700 metres above sea level the rubber trees, will be harmed the cold air of the lakes in winter, above 1000 metres above sea level, the temperature decreases with height, the rubber trees can not grow up.700-1000 meters is the best altitude for the rubber trees to grow, not only because of the warm belt formed dy inversion, but also of the abundant precipitation formed by the slope.
  • Ye Xiangqing, Chen Tiecheng, Leng Daming, Jin Li
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    The method of collecting 14C samples in natural water by precipitating was dealt with in this paper. Through experiment the best conditions for precipitating were determined. They are the pH Value of 12 and by adding precipitants two times as much as the equal equivalent, the rate of separating out of inorganic carbon in this work is 99%, and the recovery rate is 97%. The authors suggest that SrCl2 should be replaced as precipitants by CaCl2, then the cost of collecting samples could be reduced.
  • Sun Yuqiu
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    Because of the arising of the modern remote sensing and space techniques, the scientific research of remote sensing techniques for land survey in USA has been rapidly developing since 1970's. The presence of the USGS land use and land cover classification system for use with remote sensor data is one of the most important events of USA land survey during this period.At the same time studies in applications of remote sensed images from various platforms and sensors to land surveys have achieved great successes, while great advances in the techniques of acquiring and processing images have been made. Diverse image-analysis techniques are actively developing, including manual interpretation techniques aided with photo-electronic devices and computer-assisted analysis techniques. After landsat 4 MSS becomes a forma] operational sensor, quite a bit of attention is being paid to the application potential of the new type sensed data TM. The preliminary experiments have shown that TM data are very efficient means of surveying agriculture and urban land use. Experts say that the space shuttle flight will be one of the most favorable options of Earth remote sensing for users in the late 1980's as well as in the 1990's.In relation to the practice in China, finally, this paper makes some suggestions in view of the special situation of remote sensing research in land survey in China.
  • Gao Yongyuan
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    The Chinese Institute of Geography was founded in 1940 at Beipei, Chongqing, Sichuan province.It moved to Nanjing in 1947 and was closed in 1949. Within the decade (1940-1949), it carried out investigations of the eastern part of the Sichuan Basin, the Hanzhong Basin, the Gansu province, the Qinghai province and the Xinjiang province, and also made short-terra oceano-graphical observation along the Dongshan Island, Fujian province. Among the seven or eight scientific results that the Institute has published, "Report on the Geographical Survey of the Jialingjiang Drainage Basin" is noted by its spciailty.For instance, the chapters of "The Channel Geomorphology of the Jialingjiang" and "The Settlement and Its Population" and so on, are rich in contents and rather penetrating in observation. "Report on the Geographical Investigation of the Hanzhong Basin"is marked by its integrity and distinctness in the elucidation of the relationships between nature and human life, and also in the delineation of its geographic chracteristics. They are really fine records of regional geography, "The Economical Atlas of Sichuan Province" is the first such atlas in China with rather complete divisions and subdivisions and in an adequate way of illustration. The three publications above-mentioned have made contributions to the development of modern geography in China In addition, six volumes of "Geography" quarterly were published too, at that time.