GEOGRAPHICAL RESEARCH

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THE SHORELINE EVOLUTION AND THE DEVELOPMENT MODEL OF THE HANJIANG RIVER DELTA DURING THE PAST 6000 YEARS

Li Pingri

1987, 6(2): 1-13. https://doi.org/10.11821/yj1987020001

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¹⁴C geochronology, sedimentology, geomorphology, historical geography and modern dynamic process methods were applied to prove the positions and evolution trend in 6000 ys.B.p.,5000ys.B.P., 4000-2500y s. B. P., Han Dynasty, Tang Dyansty, Late Song Dynasty and Qing Dyansly.The development model of the Hanjiang River Delta was suggested as follows. 1. the delta had two development stages, the river had two-class distributaries, 2, the shoals and sand bars linked up river banks and the plain extended, 3. flood and wind carried deposit and built up land 4 the west distributary shrank, the east distributary developed, and the main river moved north-eastward.

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LANDSAT DIGITAL IMAGE PROCESSING AND ITS ANALYSIS IN PRINTING FOR CARTOGRAPHY

Zhang Jin, Fu Suxing, Wang Enyao

1987, 6(2): 14-20. https://doi.org/10.11821/yj1987020002

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The quality of Landsats image can be improved considerably by digitel enhancement and image processing in printing for the thematic cartography. The result image is exquisite and abundant and this mav be useful for many applications.In recent years, we have made experiments by using computer image processing combined with colour printing in an attempt to produce a 1:250,000 scale printed image with high quality and low cost, which would have a wider applicability, The procedure used consists of three stages, digitalimage precessing, colour scanning processing and colour printing.The equipments used for the experiments are image processing system 101, film writer C-4300, colour scanners SD-1000 and SD-701.1)Digital image enhancement. A. number of digital image enhancement methods, including frequency domain and spatial domain have been tested, among them we choose histogram transformaton methods. To study the effect of these methods, we select a typical area of Tianjin frame. The original and enhanced ima ges and it s histograms are shown in Fig.1. For example:logarithmic enhancement, transformation of grey level adjustment, histogram equaliztion, local enhancement, trackball linear mapping and piecewise linear enhancement etc. 2)Analysis and comparison of enhancement effect.It is noted that the enhancement methods mentioned above have improved the image in varying degrees, For a full frame enhancement,the linear enhancement is a simple and effective method.3}Imege processing in printing for cartography: Continuous Lone scanning, the density of digital enhanced film of Tianjin is within the range of 0.31-1.44 and after scanning this range is expanded to 0.2-1.9, the intersection point of the two curves is determined by studying the features of the image.It is about 0.6 for Tianjin.Halt tone scanning. It is important to adjust the tone of each band for producing an image of good colour effect.The last is plate making and clour printing, and this is a standard process.A high quality Landsat image is necessary for human visual iuterpretion and thematic cartography. For this purpose, en experiment of digital image processing combining with colour printing to produce a 1:250 000 scale image has been made. Several landsat frams. including the areas of Beijing, Tiaji, Tangshan are processed by this procedure, and the quality of these images is improved considerably.

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AN ARIDITY INDEX BASED ON ENERGY BALANCE

Tang Dengyin

1987, 6(2): 21-31. https://doi.org/10.11821/yj1987020003

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A long history has been experienced to research into the geographical aridity and humidity by use of various indices, This paper briefly reviewed some typical indices in the climatic classifications such as Koppen's, Thorn th-waite's and Budyko's types. Summing up, the indices were gradually developed from empirical, semi-empirical description to physics-based method.it is an opportunity to derive new index as the achievements of earth sciences such as energy balance, water balance and related technique, have been made in the last decades.

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CLASSIFICATION OF FUNDAMENTAL TYPES OF GEOMORPHOLOGICAL FORM IN CHINA

Li Juzhang

1987, 6(2): 32-39. https://doi.org/10.11821/yj1987020004

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Geomoronology is a science dealing with the morphology of earth surface. Since the morphology of the earth surface is moulded by combined action of endogenic and exdogenic agencies, attention should be focused on the genesis of morphology in classifying morphological types. By using fuzzy mathematics, this paper gives some ma thematic definitions of mountain, hill, plat-form and plain, and further more, establishes indices for the classification of fundamental morphological types based on the maximum membership princi-ple.Two schemes of more detailed classification of fundamental morphological types have been designed that pay more attention to residual steplike geo-morphological structures and, especially, to the developing ones. Also a brief remark on their merits and demerits has been made

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STUDIES ON THE RELATIONSHIP BETWEEN HYDROLOGICAL ELEMENTS AND ELEVATION

Jin Donliang

1987, 6(2): 40-47. https://doi.org/10.11821/yj1987020005

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The hydro logical elements——precipi tation, runoff,and evapotranspirationwith different elevation give different distributional regularity. For middle or small region scale (such as a middle or small watershed, a high hill) the amount of precipitation or runoff increases with elevation and the amount of evapotranspiration decreases with elevation, Forlarge region scale (such as a large watershed or a large mountain range) the amount of each hydrological element decreases with elevation. Using this principle of spatial hydrology, the problems on scarce gauging station in moutain areas and distribution of hydrological elements with orographic influences can he solved.In the paper there are four parts to be researched:1. Relationship between annual rainfall and elevation, 2. Relationship between annual evapotrans-piration and elevation. 3. Relationship between annual runoff and elevation; and 4 The application on the conception of spatial hydrology.The results of these studies have been applied in streamflow assessment in the western part of China, where hydrologic data are incomplete or lacking. In the southern part of Tibet, after assessing, streamflow increased about 900 million cubic meters as compared with the primary result of that region.

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A PRELIMINARY STUDY OF THE MODERN CLIMATIC CHANGE IN HENGDUAN MOUNTAINS

Wa Xiangding, Lin Zhenygo

1987, 6(2): 48-56. https://doi.org/10.11821/yj1987020006

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The Hengduan Mountain area Lies in Southwest China, including Parts of East Tibet, West Sichuan and Northwest Yunnan, and has a varied topogra-phy.The average altitude of it is over 3,000m a.s.l, The climatic change during Historical Time in this area has not been studied because of the lack of data.By field investigation, the authors have got a large quantity of tree ring specimens in the area. After preliminary dating and necessary dendrochro-nological processing, twelve standardized deadrochronologies have been built Baaed on these chronologies, two curves including the fluctuations of the air temperature and the annual precipitation during the last hundreds of years in the mountain area were drawn,Some significant cold/warm and dry/wet periods could be divided also.A combined analysis between dendrochronologies and historical literature data which have five classes could help us to understand the successive variations of each climatic pattern since 1600 A.D. In addition the amplitude and periodicity of climatic change in the area have been calculated in this paper.It is obvious that the chief characteristies oi the modern climatic change in Kengduan Mountains might be concluded as follows.1)The temperature fluctuation during the last four hundred years in the area is similar to that in Tibetan Plateau, and the coldest period occurred in the first half of the 17th century.2)The long-term oscillation of precipitation is more obvious than that of air temperature.3) The statistical feature in the present century is, on the average, lower temperature and lower precipitation, but the climate pattern with high temperature and low precipitation has been increasing since 1950's,4)The amplitude of climatic variation in the area is smaller than tha t in Tibet or in the plain area located on the east of Tibet Plateau.5)By carrying out analysis on various series, some periodicities have been found, such as "quasi two year pulse", s. 6 years, 35 years and so on.

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PROFESSOR ZHU KEZHEN (Co-Ching Chu) IN THE PERIOD OF 1920-1925

Shi Yafeng

1987, 6(2): 57-63. https://doi.org/10.11821/yj1987020007

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Zhu's scientific achievements have secured him a prominent place among the pioneers of climatology and geography. But he is worthy of recognition also from has activity as teacher and inspirer. The first department of geosciences was. built up by Zhu in Nanjing, when he was a prolessor in the Southeastern University by 1921. Many of the old generation of Chinese geographers have heen taught and inspired by Zhu, "Which fromed the bases for Zhu Lo be an excellent administrator and coordinater of biosciences and geosuienees later.Zhu's early scientific publications were devoted to the studies of typhoon, climate and climate changes calender, as tronomy, history of sciences and land-forms. 44 articles were published during 1920-1925.

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THF ALLUVIAL DILUVIAL APRONS AT THE EASTERN FOOT OF THE TAIHANG MOUNTAINS AND THE CHARACTERISTICS OF THEIR REMOTE-SENSING WATER BEARING IMAGES

Zhou Yongling, Guo Qingshi

1987, 6(2): 64-69. https://doi.org/10.11821/yj1987020008

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In this paper, we used the satellite pihotos ai both various time and bands provided by the American Land Re-source Satellite in interpret and analyse the alluvial-diluvial aprons at the eastern fool of the Taihang Moun tains and the characteristics of their remotesensing wa ler-bearing images.We made full use of the advantages of remote. sen wing image with wide, sight and high resolution in The process of in terpreting. U nder the prerequisite that regional interpretive marks were established, we delineated the scope of alluvial-diluvial aprons at the eastern foot of the Taihang Moun tains, then deduced the folding stage relation between the aprons and their developed history. Basing on remote-sensing water-bearing images and combining with regional geohydrological informations, we divided the alluvial-diluvial aprons at the eastern foot of the Taihang Mountains depending on whether the gro-uudwaler resourceis rich or not.The work provided the interpreted remote-sensing results Tor investigating an dprospecling reasonably ground water resource in this region.

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BACKGROUND VALUES OF METAL ELEMENTS IN RIVER SEDIMENTS WITHIN THE BEIJING AREA

Yang Weili

1987, 6(2): 70-79. https://doi.org/10.11821/yj1987020009

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The research on background values of metals in the river sediments is a basic work for the impact assessment In the aquatic system.Total Cu, Ph., Zn, Cd, Ti, Fe, Ma, Ni, Ca, Cr, Hg were extracted bydigesting 1-2 gram of air-dry sediments in aqua regia-HP-HClO₄, HNO₃-H₂SO₄-HF, HNO₃,H₂SO₄-V₂O₅ and analyzed by the flameless atomic absorption CWFD-1/2) and atomic absorption flame emissio-spectrophotometer (A-A-640B) and cold atomic absorption (CG-1). In this paper, D the numbers of necessary samples of Cu, Pb, Zn, Cd, Gr, Hg in river sediments of the area for a given level of statistical certainty were computed. 2) The distribution types of background values of metals were determined by vestelivs statistic method, the background values of metals in the river sediments were computed.3)The eocrelation coefficients and step-wise regression and factor analysis on the chemical composition data in the sediments were performed by a computer.The correlation between the metals was discussed. 4) Background contents of metals in river sediments were compared with those in rocks and soils in this afea.The results showed the background values of metals in river sediments in the area are in normal rangea.The distribution of backvaluea and correlation and translation of the petals in this area are dominantly effected by regional geology and hydrogenetic geochemistry.

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THE RADIATION CLIMATE OF TAIWAN, CHINA

Liang Guozhao

1987, 6(2): 80-88. https://doi.org/10.11821/yj1987020010

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Components of tbe radiation balance in Taiwan has been calculated by using climatic data collected from 22 statrons.The suitability of the empirical formulae used has been briefly discussed.It is found that the radiation climate of Taiwan, influenced by landform, monsoon ami sea currents. varies greatly with different regions and altitudes. Annual global radiation ranges from 100keal/cm² in the northeast to 140kcal/cm² in the southwest and 150kcal/cm² in the high mountain areas,Net radiation in the southwest is as high as 70kcal/cm² or more, while that in the northeast lies below 150kcal/cm². Based on the analysis of the temporal and spatial distribution of the components,the province is suggested to be divided into five regions with different radiation climate, the Northeast. the East,the West, the Southwest and the Central.

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COMMENTARY ON CHEN QIAOYI’S “STUDIES OF ‘NOTES ON BOOK OF WATERWAYS’”

Zhou Shi

1987, 6(2): 89-91. https://doi.org/10.11821/yj1987020011

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The present paper centres on the academic value of "Studies of ‘Notes on Book of Water ways'", a new work by Professor Chen Qiaoyi. The author making use of large quantities of traditional gazetteers and en cyclopaedias (Lei shu), collecting a wide range of data and basing on his profound learning in ancient literature and classics, has so successfully developed a new research method from the old one that he achieves in further perfecting the compilation of the lost data and in paving a new way to the research in Li-ology. This paper also makes high evaluation of the author's scientific comments on many problems in "Notes on Book of Waterways", especially his supplements to Li's "Notes on the Jianjiang River"——an uncommon contribution of the authorthat deserves high commendation.The book, putting aside the frames of "Notes on Book of Walerways", represents rich fruits of such multilevel, multiangular and multh disciplinary comprehensive researches that not only the Li-ology students but also all those who arc specialized in history and literature should read the book, for here lies a wealth of historical data either unknown to or overlooked by our predecessors

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The Primary Study of the Cenozoic Paleogeography in the Fandai Basin and its Rounding Mountains

1987, 6(2): 92-92. https://doi.org/10.11821/yj1987020012

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On the Urban System of Yichang Region, Hubei Province

1987, 6(2): 92-92. https://doi.org/10.11821/yj1987020013

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