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    Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Sun Wenchang, Qi Chengliu, Li Shuzhen
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    Northeast of China is the largest region of the volcanic distribution in our Country. In this region thre are more than iO volcanic groups, and 800 volcanos, which make up 80 per cent of the whole China volcanos.The volcanic resources are characterized by spotted distribution, synthesis and speciality. The famous volcanic groups in Northeast of China are Chang baishan, Wudalianchi, Longgang, the Jingpolake, Yitong, Keluo, Erkeshan, the Nuomin River, Aershan, Abagaqi, Dalinuoer and so on.The perspective of utilizing volcanic resources in Northeast of China is very bright in the fields of scientific researches, tourism, terrestrial heat, recreation, constructive materials and so on.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Shen Changjiang, Guo Aipu, Wang Shiquan
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    The regional differentiation of chromosomes and haemoglobin of Tan Sheep, a special fur breed in dry semi-desert in the Northwest of China, were studied with the ecogeographical points of view and methods, and the interesting results had been discovered. The fur charac-terestics, the chromosomal aberrations, the types of haemoglobin (Hb), and the other economic performances of the populations distributed in the desert, desert-steppe and dry steppe regions had been examined. The same items were also examined in the population of Mongolian Sheep, the ancestor of Tan Sheep, but is distributed in Inner-Mongolia Plateau. The regularity of geographical differentiation is concerned with the same differentiation of natural environments. Five parts of this paper are: 1) the main characteristics of the populations of Tan Sheep; 2) the ecological environments of those populations; 3) the regional differentiations of chromosomes; 4) the regional differentiations of haemoglobin (Hb); and 5) conclusions.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Fang Rulin
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    In the northern area of China according to the ecological environment and the elementary characteristics of water resources and dynamics of water and salinity, and from the viewpoint of coordinating the exploiting water resources for developing irrigation with improving ecological environment, some expositions are given in this paper as follows.(1) The exploitation of water resources at most irrigation districts of the northern China plain must combine the surface water with groundwater as a whole in comprehensive utilization Above all, the shallow groundwater ought to be exploited enthusiastically. The surface water can only be channelled properly under the condition of the demands of reasonable regulation of the shallow groundwater.(2) A project of water and soil conservantion of the constrvction of reservoirs, water can be clear and sand can be drained are necessary to put into practice at hilly and mountain districts. and the stor age of loodwater at plain districts, lo channel muddy floodwater into the warping field and develop well irrigation of floodwater techarge are basic ways of harnessing a muddy and sandy river and regulating 'he runoff storage. From all of these measures, devoting major efforts to developing well irrigation of floodwater recharge is a key link in changing bane into boon and using the floodwater and sand resources fully.(3) Provided that shallow groundwater is exploited positively and managed scientifically, then the problems of combating alkalinity, eliminating drought and preventing waterlogging will be tackled in a comprehensive way of strong water to combat the drought. From the view point of metioned above to investigate the strategy of water control, it is important to transform the policy of drainage into storage or to combine the storage with the discharge.(4) The combination of wells with canals and the use of water in cycles for developing irrigation are effective methods of raising the utilization ratios of irrigation water and the ensuring degrees of water prorision. In the meanwhile, it is able to lighten the burden on the drainage in the irrigation area. These provide a precondition for the prevention and control of alkalinity, waterlogging and pollution of water sources caused by agricultural drainage. They seem to be some economic and rational water conservantion facilities. Also, the methods should be the most significant irrigation installations of the surface water use at most plain districts in northern China.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Tang Qicheng, Li Xinyun
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    In this paper the autoregression correlation coefficient method is adopted to analyze the characteristics of the dry-season runoff of the rivers in the arid region of north western China. The paper first described the physical geographic elements affecting the dry-season runoff, and it is known that climatic elements and hydrological states are main ones which affect the dry-season runoff. The data used 10 calculate autoregression correlation coefficient from first step to tenth step are minimum monthly mean runoff and year minimum runof of the thirty representative stations in the north-west arid region. By analyzing the coefficients, the coefficients may be divided into three types, the first type is with low coefficients to any value of τ, the second with high coefficient ar T = l or 2 and the low values as τ>3, the third with the high values to any value of τ. However the type of the dry season runoff in the north-west arid region all belong to the first and second type, especially the first type. The autoregression model predicting and estimating the dry season runoff can be developed on the basis of the calculation and analysis of autoregression correlation coefficient.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Shen Yuancun
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    Chai Da Mu Basin is a famous geological sunken basin of Qinghai-Tibet plateau in China. The natural Characteristics of this basin belong to frigid and arid climate. It is rich in mineral resources and has a great future to build up a large-scale mineral base for exploiting the mines. It is also rich in natural resources for agriculture. There are more than 850 thousands mu that can be developed for agriculture or other purposes, and there are about 200 thousands mu that adapt agriculture.According to the regional differentiation of the resource distribution and the condition of economic and social development, Chai Da Mu Basin is planed in 8 economic districts for Exploitation of the natural resources.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Xu Qiaoli
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    In this paper we discuss the following three problems:(1) Why do we have to study the macrodesignment of agriculture by research the natural resources structure of agriculture?(2) What's the methods we have adopted to make clear the natural resources structures of agriculture?(3) The application of marcodesignment of agriculture to the research of the natural resources structures, how can we do?This article should explain the mocrodesigniment of agriculture, and the materials of this paper were collected from the mountainous district of Hubei Province. This paper refers mainly to three aspects: (1) how to allocate the producive forces, (2) adjustment the agricultural ecosystem, (3) how to build up the base of commercial products of agricuture?
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Su Daxue
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    Studing natural grasslands of 84 counties in Guizhou Province and analysing 1331 quadrate samples, this paper explains that they are the grasslands with secondary characteristics, most of them are unstable, situated in the succession from grasses to bush to forest, besides, there are also relatively stable alpine meadows and bush-grasslands with plagioclimax.The grasslands in Guizhou Province are mainly scattered patchily among the woodlands and agricultural fields. Large area of these grasslands are located on the middle-mountain areas and plateaus with the elevation above 1000 m, these places are characterized with small population, long distance from settlements and difficulty of accessibility. The grasslands often stretch contineously as a belt on the ridges and tops of the middle-mountains.The total coverage of the grasslands in Guizhou, is about 80-85%. The thickness of the grass layer is about 60-70 cm, and the yeild of the fresh grasses is about 6,000-9,000 kg/ha. The growing times of green grass is about 240-300 daysannually. There are 96% of grasslands can be used for cutting for making hays. The grasslands in Guizhou abound with variant plants, mainly winter-green or evergreen grasses. The alpine meadows have relatively high value for animal husbandary. Most of them are suitable to exploitation with advantage ous. condition.The quality of the grasslands in Guizhou is poor, 76.5% of them are deficient in legumes, which occupy only 0.96% of the total grasses by weight, they are the grasses with low content of protien. There are about 40% of these grasslands with thin soils depth less than 30 cm, and there are about 50% of the grasslands with slopes more than 25%, about 74.8% with bare rocks or stones and 25% are suffered from soil erosion. The durability for grazing is poor. All of these, to some extent, are the limitation of their exploitation.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Cheng Weimin, Xu Xueren
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    Hunan Province is in the middle part of the subtropical zone in China and in the transition region of the eastern and western parts of the mid-subtropics. The natural environment and re- sources are imbued with a distinct transition characteristic. Within the Hunan Province the natural condition is advantageous, the structure of natural resources of agriculture is fine, as well as the utilization ratio of land and energy of sunlight is high. But the resources are affected by regional distinctions of the natural and social economy, and present a distinct regional transition. This paper makes a primary investigation mainly on the reginal distinctions, the present condition of exploitation and utilization, and the orientation of rational exploitation anduilization of resources.The forests, the cultivated land and grassland resources are the three major sectors of agricultural natural resources. Hunan is one of the important forestry regions on the south of Changjiang River. Its amount of forest reserves occupies the fourteen position in China. But it is still not reasonably utilized at present and has the tendency to come down. We should strengthen the forestry construction of mountain areas and build Hunan into a large-scale base of timber forests and economic forest in the region on the south of Changjiang River. Hunan is one of the provinces with more people and less cultivated land in China. Although the total output of grain occupies the fourth position in the country, but the exploitation of resources does not balance. It has not yet fully to bring out the productive potentiality of resources. Only in the Basin of Lake Dongting it is possible to be built into one of the largest bases of commodity grain. The fragment, pieces and intersecting distribution of plough and forest are the distinctions of grassland resources of Hunan, which is classified as two types: (1) fragmentary grassland of the low-mountain and hill, (2) the continous grassland of the middle-mountain. In the light of its distinct of the suitability, We should adopt a thousand and one families or the main orientation of utilization of resources. The middle-mountain grassland is the outcome of the unstable stage of abverse succession in ecosyston of evergreen broad-leaf forests. If it is to be used as great grazing land, a prudent altitude should be adopted.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Chen Baiming
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    This thesis approach to the methodology of series study for the land resources, including classification, evaluation, optimization model and carrying capacity of land resources, taking the oasis of the Hutubi County, Xinjiang Uygur Autonomous Region as an example.First, the type of land resources was divided and the system of classification was established. Then, the elementary types of land resources were used as a land mapping unit to evluate the land quality and its suitability. Based on these results and the main natural, ecologic, social and economic conditions affecting land use, the optimization scheme for the utilization of land resources was selected by linear programming through IBM-PC computer. At last, based on the yield levels of the first-class land resources, the population supporting capacity of land was calculated to meet the productive conditions which the optimization scheme should require. That is to calculate how many people could support by one mu or one ha arable land based on the calculation of mean intakes of calorie and protein every member in our country. The calculations, compared with year 1984, demonstrated that population supporting capacity under the optimization scheme of land use will enhance evidently.
  • Special Column:Celebration of the 70th Anniversary of IGSNRR, CAS
    Wang Bennan
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    In this paper the methods of estimation of plant density by the distance sampling, the parametric and .nonparametric estimation were discussed. Using a practical example, the theoretical formulas were examined. It was found that the nonparametric estimation based on ordered statistic is more available and useful for survey and investigation of forest resources.