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  • 1982 Volume 2 Issue 3
    Published: 20 May 1982
      

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  • Huang Xichou
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    Mire science is a new branch of physical geography in China and the history of study is shorter.So some basic theories and concepts are not veryclear and definite.Some ideas from foreign countries have been uesd in China,but they are not suited to the characteristics of out marshes.Because of vast and unbalanced mire distributions,scholars have two different views on geographical regularity of mire distribution.Some hold that mires are distributed intrazonally or azonally.Others maintain mire disributionis largely zonal.In this paper,the author cited some opinions proposeed by some scientists and examples showing zonal distribution.Author suggests that the distributions of various types of mires are restricted by the law of natural differentiation.Although mire develops in a certain zone,it does not occur-isolately in the zone,and it is closely related to and interacts with around zonational ecological environments.The natural complex in intrazonal environments bears evidence of zonality.Therefore,the author considers that mire distribution possesses zonaland intrazonal characteristics.The unified theory of mire genesis has been used in mire study and regardedas basis of mire classification.Analyses of pollen and C14 dating indicate that the theory is only suitableto frigid temperate taiga zone.China’s mire has mostly remained in the stage of low moor since the Holocene.There is not certainty of the law developing from low moor to high bog.The development law of mire not only depends on time,but also is restricted by space and sites.So it is not suitable that developments of all miresare included in a unified pattern.Mire develops as multi-pattern.
  • Wen Qizhong, Zheng Honghan, Han Jiamao, Wang Junda, Lin Shaomong, Qiao Yulou, Wei Lanying, Diao Guiyi
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    Nuanquangou loess section at Longxi basin has been examined in terms of stratigraphic investigation,radiocarbon dating,paleomagnetie polarity,and spore-pollen diagram mineral and chemical analyses.The results indicated that the section is one of acient loess sections with a continuous sedimentation and composed of homogeneous materials with rich-carbonate.Brunhes/Matuyama boundaryand Jaramillo event were recorded in the section.Stratigraphically,this section can be divided into Holocene and pleistocene loesses.The latter included Malan,Lishi and Wueheng loess in descending order.They developed at the age beginning at ca.1.2m.y.Whereas,Nuanquangou section reflects several local characteristics different from those on other areas.
  • Chen Zhongyuan, Yan Qinshang
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    Hutuo River in Hcbei province may be divided into two morphological reaches.The upper reach is a braided river,about 100 km.from Huangbizhang to Shunzhe.The lower reach is a slightly meandering stream,80km.from Shunzhe to Xian—Cotmty,where it connects with Fuyan River,flowing down into BouhaiGulf.In braided river,the longitudinal bars are mostly composed of the followin gvertical beddings from bottom to top:lag deposits of poorly bedded gravels and sands,horizontal beddings of upper flow regime,large scale trough beddings,small scale trough beddings and parallel beddings of lower flow regims. Near the lateral margins of longitudinal bar,although most beddings of the vertical section are similar to those mentioned above sequence,yet instead of horizontal beddings of upper flow regime,large scale tabular cross beddings take place,indicating that they are formed by sandwave migration of relative lower flow regime.The average thickness of recent longitudinal bar deposits of braided course is very thin,only about 1.0 m.In slightly meandering stream,trenched profile sections show that two different vertical sequences of point bar accur.At the leeside of point bar,where flow is gentle,large scale trough beddings predominate,the whole section is similar to the fining-upward model of point bar deposits as stated by J.R.L.Allen(1970).whereas,at the stoss side of point bar,where flow is swift,large scale longitudinal cross beddings predominate,which consist of a bundle of cross beds in different directions,and no rhythmic variation of grain size appears in the vertical section.The average thicknees of recent point bar deposits is above 2.0 m.The sequential beddings of natural levee from bottom to top are:r2 small ripple bedding,r3 ripple bedding,r4 supperpose bedding,r3 ripple bedding,r2 small ripple bedding,r1 parallel bedding.They are the deposits along high river banks by relatively slow—moving flow during flood period.Beddings r2 to r4 and r3 to r1 represent the semicyles of upraizing and receding of flood respectively.
  • Shen Yuancun, Xie Xiangrong, Yang Liulin
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    One basic approach of the integrated physical geography is to study land types of certain region.Present artical tries to study land types of Chang Ping county,Beijing,as related to agricultural regionalization.The tem“land”is treated as the integration of all physical factors,while landform,vegetation and soil are chief criteria for classifying the land types.10 land types of frist category and 42 land types of second category are identified in Chang Ping county.Areal structure of land types is the basic for agricultural regionalization.Chang Ping county may he thus divided into four agricultural area:1.Alluvial plain-farming area;2.Diluvial fan-grain and Fruit area;3.Frontalhill-pasture,fruit,and grain area;4.Mountain forest area.
  • Fan Zhengyi
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    The general maps are divided into two types——the topographic map and the general geographic map.In this paper we have mainly discussed about the latter.The general geographic maps will d velop in the following aspects:1.To enhance the geographic characteristics of the general geographic map.The imageries of landsat and the large comprehensive or regional geographical investigations would increase the geographical features of these maps.2.To reform the process for the general geographic mapping.we can try to transfer the contents of the landsat imageries onto the general geographic maps directly.3.To make applications of computers and automatic mapping.In the near future,we can establish data banks and use the computers for collecting and compiling the map information.4.To make better use of the general geographic map as an information communication system.This is a new development for the general geographic map.How to show the regional features? To study the internal relationship of the regional features and to show their distribution rules on the general geographic maps are the chief tasks of our geographic cartographers.
  • Li Xiuyun
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    This region is located at 40°—53°30’N and 120°-135°E in the temperate zone.It is one of the main commodity grain bases of China and of areas with aboundant water.The regularity of distribution of runoff is rougthly coincident with that of annual precipitation.Both of them gradually reduce form south-east to north-west.The perennial change values are large,the maximum value of Cv is above 1.0 and the lower value is below 0.3.The annual runoff regularly changes with alternativeplentiful-drought cyclical period and this cyclical period is the longest in China(60—80 years).The analysis of annual runoff in plentiful and drought period can reflect the basic drought and waterlogging situation of this region.The cyclic analysis of annual runoff shows:change of eyclical period at Haerbin Station is different from that at Shuifeng Station(about 52 years for Haerbin Station and about 32 years for Shuifeng Station).This shows there is rather great difference of annual runoff in the northeastern region in geographical distribution.Furthermore,we can prognosticate qualitatively and quantitatively the annual runoff of this region by using the method of mean sliding periodic trend of annual runoff to provide a scientific basis for exploitation and utilization of water resources in a planned way.
  • Ma Xiangyong
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    The study of agricultural production type at county level is the fundamental task to formulate agricultural plan suited to different local conditions,to make rational use of natural resources and to realize agricultural modernization.Agricultural production type refers to a sort of combination fomed by a ceritain territory of which structures,properties and characteristics of agricultural production are basically the same.The characteristics of diversified production and tne strong territorial features of the agricultural production type provide a realistic foundation for dividing agricultural production type.Such type is not only a transitional step for agricultural division,but also a basic unit to the regionization,.Thus,a good foundation can be laid for the accuracy of regionization by division of the type within a county beforehand.The development of a rational principle for division is an important basis for the division of agrcultural production type.Index can be regarded as the principlein concrete from.The limits of territorial differentiation of agricultural production based on the quantitative analysis have to do with the accuracy of the line of division.There will be a relative flexibilty for the different indice to be adopted according to different regions and production levels.
  • Chen Gangqi, Zhang Wenfen
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    This paper attempts so approach the effect of swamp on river runoff under the special natural conditions of the Sanjiang plain through the establishment and analysis of the relation between annual rainfall and runoff of swampy rivers.The results of analysis show that the influence of the swamp in this area on river runoff is presented as follows:runoff volume,runoff increment,intercept of correlation curve,precipitation needed for creating surface flow,runoff during dry years and laging time of annual runoff are all related to swamp distribution.This kind of influence varies with the geomorphological location on which swamp lies,and related to climatic changes over years.The swamp distributed on piedmont dip plains and river terraces influences river runoff mainly through feed changes.Runoff increment caused by every precipitation increment in swampy basins is larger than that in non-swampy basins during continuous high-water years,while it is quite contrary during continuous low-water years.The swamp in these basins plays a part in intensifying runoff changes over years.The swamp developed on flood plain regulates runoff principally through its storage and permeable characteristics for water just as lakes and reservoirs take effect on making yearly changes of river runoff even.
  • Fu Deyi, Zhu Yanming, Huang Xichou
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    Except only a few of the trace elements in dominant plants of different vertical landscape such as Sr,Se,Zn,etc.do follow normal distribution,but most of the others are of logarithmic normal or normal deviation distribution.Study indicated that these elements are stable in low concentration in these plants,but the frequency of their high concentration occurrence is rather low.study on the causes of high concentration occurrence of trace elementrs in thes eplants can help us to reveal the abnormality of environment or physiological functional characteristics of different plants.Study shows that the plants of certain kind have the characteristics of selectively assimilating and rich collecting certain chemical elements.So contents of the trace elements in different kinds of plants are different.Trace elements in these plants are not only controlled by hereditary function but also affected by environmental factors.
  • Chen Zhiming
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    Based on the international information,this paper discusses a number of new concept,method and development in relation to current geomorphological mapping,including such principal subjects as: 1)The new orientation of morpho-structure.The contents of modern geomorphological map are based chiefly on morphostructure,or on various types of morphostrueture along with sculptural geomorphology,indicating that the geomorphological map can no longer be regarded as a map representing merely exogenic topography.2)The emergence of analytical legend.For the past ten years or so,the synthetical legend has been by degrees replaced by the analytical legend.The latterhas many advantages over the former in(1)being relatively objective;(2)getting more information available in the map and in(3)being conducive to measurements and input computer,etc.It is for this reason that the analytical legend has been put into use by many scholars in many countries.The present author holds that the application and popularization of such legend are a major task for the innovations of geomorphological map in the days to come.3)The standardization and systematization of legends.From the international development trend,it can be seen that the legends of geomorphological map of various scales(inclusive of principal way of representation)have now entered a new stage of development in international standardization.Although it is impossible to bring into it all of the geomorphological types in all parts of the world,it becomes an inevitable historical necessity to have various kinds ofbasic types and representation turn standardized.Currently,the international legends of large-and medium-scale in international organizations have won initial success,though further improvement is still called for.The said legends are more preferably to be uniformly designed,or mutually confirmed and completed.And more efforts should be made on the study of current legend to be applicable to various maps in different scales.4)The establishment of a new system of geomorphological survey.Of special importance to the geomorphological mapping in the developing countries is the “ITC System of Geomorphological Survey”put forward by the International institute for Aerial Survey and Earth Sciencs(ITC).In this system,the main experience is making full use of the results of aerial survey along with proper surface survey and probably working out series mapping of basic scaled geomorphological maps with rearer,faster,better and more economical results.This system is considerably superior to the traditional method in which the achievements made in aerial survey have been neglected and in which the mapping of maps in different scales is dones separately.5)The development of a new branch in geomorphology(geomorph-carto-graphy).Looking back on the history of the development of geomorphological mapping,the present writer gives an account of the nature and contents and the main works in the field of geomorph-cartography.It is concluded that as a newly branched gcomorphology,geomorph-cartography has now reached its maturity ready to make contributions to the develpoment of geomorphology as well as its practical application.