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  • 1990 Volume 9 Issue 4
    Published: 15 December 1990
      

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  • Hou Feng
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    The paper deals with the problem of provincial industrial structure in China,The resemblance of industrial structure among provinces is recently the main characteristic of industrial development in China, The departments of constitutional resemblance are usually the major departments while the departments of dissimilarity are the minor ones in the industrial structure of provinces,The departments of constitutional resemblance includes the following. (1) Raw materials distribute extensively, (2) Products are not suitable for transportation distantly, (3) Products are demanded by the local consumption, (4) Labour force intensive industries, such as food products, textile mill products, machinery, chemical products, construction materials. The departments of constitutional dissimilarity includes the following. (1) Raw materials concentrates locally, (2) investment intensive industries, (3) advanced technique industries, such as metal mining, oil and gas extraction, petroleum refining, chemical fiber, electronic and communication equipment. The resemblance is rational because the decentralization is decided by its location factors, The departments of dissimilarity should be developed in. order to improve specialization among provinces.The main difference of industrial structure among provinces exists in the inner-department, that is, the comprehensive capacity of specialization which represents the scale of the department,the connexion of inner-department and products constitution, the economic efficiemcy of every department.The foundation of rational industrial structure is decided by the rational policy of national industrial location, including. (1) substituting the pattern of province-wide polarization and diffusion for nation-wide pattern of economic development,(2) expanding the production-consumption, cycle of raw material industry in the region of province or neighouring provinces, (3) locating the manufacturing industries along cities and main transportation lines, (4) improving the adjustment of innerdepartment in the less developed provinces.
  • Hou Shaofan, Li Dezhu, Wang Lizhen, Wang Wuyi, Tan Jianan
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    The experimental procedure to separate different species of soil selenium was proposed according to Jackson,Relationships between contents of 7 selenium species, distribution and availability to plants was studied in major soil in China,The results revealed that the concentration of water soluble selenium in alkaline soils are significantly higher than that in acid soils. Amount of unenveloped selenium form is correlated with total soil selenium. And amount of unavailable enveloped selenium form is interrelated with iron and aluminium in soil, which demonstrate that the unavailable enveloped selenium is mostly fixed by Fe oxides and Al oxides. The percentages of residue selenium vary slightly in different soils. The availabilities of selenium in soils in low selenium belt are similar to those in normal area. Therefore, low selenium content in plants results from low level of total soil selenium.
  • Li Kerang, Lin Xianchao, Wei-chyung Wang
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    By using the data of air temperature from 1951 to 1988, the processes of letnperature variation and its distribution of time and space are analysed, especially for the variational trend and warming of the decade span. The results show that the decade average temperature increases from 1950's to the present and is higher 0.2℃ in 1980's, which processes and trend have good agreement with the north hemisphere. The trend and intensity of the decade span temperature variation have quite great difference among zones and seasons. Generally, warming amplifies with the latitudes from south to north. Comparing 80's with 50's the most obvious warming is in Northeast China, Average temperature increases 0.7℃ there and 0.5℃ both in Xinjiang and North China, In the area south to the Yangtze River, the average temperature decreases. In winter, the temperature generally increases over the whole country and intensifies heavily, such as the January average temperature increases 2.9℃ in Xinjiang,1.8℃ in Northwest China and 1.3℃ in North China for recent 40 years. However, temperature generally decreases or increases slightly in summer.The recent 40 years' variational processes of temperature in China may be divided into the following stages, in the beginning of 50's, the trend of temperature is stable, from the middle to the end of 50's, temperature decreases, from the end of 50's to the middle of 60's temperature increases, from the middle of 60's to the middle of 70's, temperature decreases; from 70's up to now temperature increases persistently and the amptitude of temperature increase is comparable to the values of the warm period in 40's, For area distribution, the varialional trend of temperature in the areas of north to 32, is accordant with the average conditions of the whole country, but in the areas of south to 32°N, especially in Southwest China, the variational trend is quite different from the average conditions of the whole country For the seasonal distribution, the variational trend of temperature in the most areas of China increases in winter and decreases in summer.
  • You Lianyuan, Jin Desheng
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    By adopting hydro-morphology theory and methods and combining with experiment in the laboratory as well, this paper deals with the following 3 aspects of problems.1) Longitudinal degradationDepending upon boundary conditions that is characterized by nonuniform distribution in 3 dimensional space, the development of longitudinal degradation, besides a general tendency, is getting weaker and weaker along the course with time and is also nonuniform. The degraded magnitude and the scouring distance, in general, can be determined by some experimental formulas established with measured data based on hydro-morphology theory,2) Lateral deformationIt is depended in a nice bit of degree upon relative erodibility of the bank to the bed. Just the same as longitudinal degradation, experimental formulas are also established, by which relationship between deformation intensity of the bank and controling factors, including boundary conditions can be represented well. Due to complex response phenomenon in adjusting process, relative erodibility of the bank to the bed decreases with time, consequently, the relationship between longitudinal and lateral deformation changes with time,too,3) Change of river patternIt is a very complex problem. Adjusted magnitude for width,depth, slope, relief of the bed and roughness and ways taken in adjusting process are different from each other in different river pattern. We establish a comprehensive assessment model, in which factors influencing on formation and development of river pattern are fully considered. It may be used for predicting of changes of river patterns after the reservior is constructed.
  • Guo Qiyun
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    The ralationships between the monsoon rainfall and the sea-surface temperature (SST) in the Equatorial Eastern Pacific are examined based on the thirty-eight-year (1951-1988) data set of sea level pressure maps in the Northern Hemisphere and the rainfall of 160 stations over China in summer (June-August) and winter (Dec.-Feb.).The study shows predominance of the years, in which the monsoon rainfall does not in accordance with the SST year to year. However, the SST anomaly takes a role which can not be ignored in examining the interannual variability of monsoon pressure field over East Asia and the monsoon rainfall in China.
  • Jin Changxing
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    Horton's empirical laws of network composition is studied and applied to six catchments in North Shaanxi Province of China, The relationships between Horton parameters are discussed.Based upon the Horson's laws, a geomorphologic instantaneous unit hydrograph (GUH) model is proposed, in which, the waiting time distribution in each path is supposed to be a Gamma distribution. General expressions for the inital state probability anb the transition probability in GUH are derived. All the parameters but one in the GUH are calculated from Horton parameters and stream flow velocity of each flood event. The unknown parameter is decided by optimization.The proposed model is applied to ten rainfall-runoff events in two catchments, the results are encouraging.
  • Wang Shouchun
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    The topic concerning the primeval vegetation has been a disputed problem up to the present since the German geographer F. V. Richthofen put the viewpoint that there are not forest on the Loess Plateau at the end of last century. To sum up, there are four viewpoints about this topic, steppe, forest-steppe, forest, and those three types of vegetation existed side by side. The existence of the divergence of this topic relates to the following two reasons. First, the natural environment has undergone destruction by human activities for a long time. Second, the scholar had limited disciplines and methods of research. According to the synthetical principle, this apper considers different factors and the results obtained by different disciplines. The times focused by the paper is from West Zhou to the West Warring States (c.11-3 cent. B, C.) because the tools of production was very primitive during those times and the impact of human activities upon nature was very weak, so nature was under primeval conditions. At the same time there were more historical materials and ancient writings. The area focused by this paper is the eastern part of Loess Plateau, The synthetical analysis is considered in the following respects, the human character of ancient Loess Plateau, historical records concerning ancient vegetation, the results obtained by pollen analysis and archeaological research. From West Zhou Dynasty to the Warring States, the human character of Loess Plateau was that the greater part of the Plateau was resided by nomadic tribes, and the farming nation distributed on the Wei River Plain and Fen River Valley, But animal husbandry and hunting were important to the farming nation. This human character reflects that grassland occupied greater part of the Plateau, According to the historical records in "SHIJI" ("Historical Records"), "CHUN CHIU ZHUO ZHUAN" ("a book about the historical records at CHUN CHIU Times)", "SHI JING" ("The Book of Songs"),"SHAN HAI JING"("the book about mountains and sea"), the grassland distributed widely, and there were a great number of wild deer on the grassland. And the bush also distributed widely. And there were scattered trees, but the trees didn't grow very well, a great part of them were small trees. And on the mountains there were a lot of trees and some hydrophyte. According to the pollen analysis the herb pollen occupied a great part of the total amount of pollen. The herb included mainly Arte Arte m Artemisia, Polygon-aceae and Chenopodiaceae, and there were a small amount of tree pollen. Synthesizing aforementioned facts, the paper reaches the following conclusion, the primeval vegetation on the eastern part of Loess Plateau were scattered trees, wide spreaded grassland and bushes. But on the mountains and valleys, the condition was different.
  • Zhou Chenghu
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    Existing landuse database system (DBS) in the area between two fjood-control dykes of the lower yellow River from Huayuankou to sunkou, based on ARC/INFO geographical information system software, was developed by using landuse interpretation maps of air infrared photos taken in June, 1988, and other thematic maps such as topographical maps. DBS is comprised of database and database management system (DBMS).The database consists of existing landuse, floodland distribution, digital elevation model. The data model is a hybrid of relational and topological models. Locational data may be represented explicitly, or topologically, as a series of x,y coordinate, Attribute data, discribing feature names, symbols and classification, are stored in feature attribute tables.Polygon overlay and isomorphic buffer operation are used to study the landuse structure and the landuse difference among three kinds of floodland. Landuse data were traped on digital elevation model (DEM), showing the spatial distribution of existing landuse and floodland.GIS-based analysis of existing landuse is featured by use of multisources information and information integration through ARC/INFO, powerful analsis functions such as spatial retrieval and query, statictical calculation and space modelling.
  • Jia Bingyuan, Wang Xuejun
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    Regional landuse evalution for the development of cities and towns is an important prerequisite of regional economic development. In this paper, with the help of Geographic Information System, the authors set up a new evalution system, it is formed by a series of models, such as Landform Evalution Model, Diffuse Models, Multi-factor Overlay Model, etc. Among these models, the Multi-factor Overlay Model is the most important one.Its action is to combine some relative evalution maps with several new maps. These new maps combine the information from the previous maps selectively, with these new evalution maps and some other material, the evalution work can be more efficient and accurate,Ilainan province is the largest Special Economic Zone in China. It is also the only large tropical island in China. So it is very important to use its land and other resources rationally and economically. The authors apply this evalution system on regional landuse evalution for the development of cities and towns in Hainan province. The result is satisfactory and we may divide the whole island into five different parts. 1, NorthUrban-Industrial Zone. 2. Green Zone, taking agriculture and other tropical crops as dominant factor. 3. Reserved Zone for Urban-Industry, 4, Ecologic protection Zone. 5. Seaside Tourist Zone.
  • Xie Xianqun
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    The author related the general situation about combined measurementt ex periment of the field evapotranspiration in Yucheng Experimental Station, Chinese Academy of Sciences during 1980-1988, and introduced the observation object, methods and the instrumentation, etc, in this paper. The author compared and evaluated the following methods. (1) Lysimeter's method,(2) Bowen ratio-energy balance approach (BREB), (3) energy balance-aerodynamic resistance method in relation to remotely sensed technique,(4) aerodynamic technique-layer gradient method. The results are as follows.1, The calculated value of evapotranspiration (ET) of the field by BREB method is 20% lower than the measured values with Lysimeter. The observed differences between BREB-estimated and lysimetrically-measurcd ET values may stem from four of the following causes. (1) underestimation or overestimation of Rn, G, △t and △e, (2) non-equality of Kb and Kw, (3) insufficient fetch, (4) overestimation of actural ET by Lysimeter. The author evaluated the applicability of the calculating ET values by BREB method.2. The author considers that Dr. Chen Jimin' s, excess resistance model and author's removed formula are better than other aerodynamic resistance-energy balance formulas, the relative error is about 11% in all stability conditions, compared with Lysimeter.3. The relative error of aerodynamic technique-layer gradient formnla is about 21% in stable condition, while in unstable condition, the error is larger.4. The author analysed the ET of some crop fields, the value of ET of the wheat field is more than 500 mm in the whole growing period (1987), the difference between ET and rainfall is about 400mm, the ET of wheat in spring is more than 300mm, but the rainfall only a few, the difference is over 200mm, so, the irrigation is necessary during the wheat growing season.Even though the ET of cotton and soybean are large (about 300-400mm), as it is rainy season in summer, yet the rainfall is large too, the difference between both ET and rainfall is only less than 100mm, If it is drought in summer (for example in 1986), the difference between ET and rain is more than 100mm and irrigation is necessary for these crops.
  • Tang Yungui
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    This paper discussed the 5 developing stages of regional geomorphology in China since the founding of our country. Such problems as research object, content about regional geomorphology and its position in the scientific system have also been discussed.