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  • 1996 Volume 51 Issue 5
    Published: 15 September 1996
      
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  • REMOTE SENSING INFORMATION SCIENCE:PROGRESS AND PROSPECT
    Xu Guanhua, Tian Guoliang, Wang Chao, Niu Zheng, Hao Pengwei, Huang Bo, Liu Zhen
    1996, 51(5): 385-397. https://doi.org/10.11821/xb199605001
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    The theoretic basis,objectives and content of remote sensing information science are described in this paper. The development of remote sensing information science has resulted in fundamental changes in the fields,objectives and methods of geoscience research,which is a sign of the revolution in the acquisition and analysis of geoscience information,and the blossoming of a new discipline. The theories, technologies and methods of remote sensing information science are widely applied in the development of the national economy. They play an imPortant role in the investigating,monitoring,analyzing, estimating and forecasting of resources, environment and disasters. The developmental trends of remote sensing information science are outlined.it is Pointed out that natural resource and environment information is an important national strategic resource,and the construction of a national resource and environment information system is of great importance.
  • AN ANALYSIS OF THE ECONOMIC FEATURES AND REGIONAL DIFERENCE OF CHINA’S RURAL INDUSTRIALIZATION
    Fan Jie, Wolfgang Taubmann
    1996, 51(5): 398-407. https://doi.org/10.11821/xb199605002
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    Before the reform, the industrialization of China took the way of "taking the cities as key areas and the investment from the state as the main resource for industrial construction".In 1978 the industrial output value of rural area accounted for only 9% of that of the whole of China. In the recent 10 years, the economic structure in rural China has gradually changed and the industry has become the main body.Of the total economic volume,the industrial output value increased from 19% in 1978 to 57%,Which was 41% of the total industrial value of China.The development of industry in rural areas was the significant characteristic of Chinese industrialization in this stage. The correlation analysis indicates that the rural industry is the base for the rural economic prosperity. The ocrrelation coefficient reached 0.985 in 1992 compared to only 0.729 in 1980. The results of the field work in 7 towns of 6 provinces have proved this correlation with regard to two aspects.First of all,the rural industry by turning over profit (10% of the net profit of the enterprise) and management fee (5% of the sales income) and social expenditure(10% of the profit) contributed to the town construction; secondly,in general the income of workers in township enterprises was 2 to 3 times higher than that of local peasants and 79% of them had a monthly income between 100 and 250 Yuan RMB.There is a great regional difference in the development level and distribution of rural industry.In 1980 the gravity centre of me rural industry was located at 116,13E and 33.08N,which was in the middle of Anhui province.The development between eastern areas and western areas was seriously unequal and the deviation coefficient was 1.15. The gravity centre moved continuously towards East until 1988 and the deviation coefficient reached its peak with 1.28. The rural industrial output value in the coastal provinces amounted to 74% of the total China. After moving North for one year the gravity centre has moved towards South continuously till 1992 which resulted in a decreasing difference between the East and the West and a slight increase of difference between the North and the South. The degree of deviation has kept stable. From the proportion of rural industry in rural economy and the proportion of rural industry in total provincial industry can we see that most of the provinces in the hinterland had a relatively backward rural industry.
  • THE PROCESS AND ENVIRONMENT OF POLAEOKARST IN THE NORTHEAST AREA OF QINGHAI-XIZANG PLATEAR
    Cui Zhijiu, Hong Yun, Gao Quanzhou, Chen Huailu
    1996, 51(5): 408-417. https://doi.org/10.11821/xb199605003
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    The widespread distribution of karst landforms in the limestone area of Qinghai-Xizang Plateau in China has attracted attentions from geomorphologists. The preliminary study in the nonheast area of the Plateau indicates that the main types of karst include pinnacle karst, clints, limestone wall, cave and "widow-like cave", and etc.The results of fission track (FL) dating of recrystalized calcites in karst caves are 15.70 MaBP,12.19 MaBP,11.68 MaBP and 10.57 MaBP respectiwly(Tab. 4),Which are all in the mid-Miocene Epoch.The results from the analysis of relevant deposit,which is relic terra rossa or red regolith,reflect a kind of subtropical climate. The vahe of SiO2/Al2O3 is about 3.30 (Tab.2),which is similar to that of the soils under subtropical. climate. X-ray diffraction analysis indicates that the average content of kaolimte in caly minerals is over 20%(Tab.3),even over 50% in some samples(such as Hx and Lms-1 and Mc-2). The quartz sand grains were studied under the ebctronic scanning microscope(SEM), some chemical modification features (Fig.2) on the grain surface indicate that the terra rossa was formed under warm and humid climate.Two main reasons contribute to the karst evolution in this area, they are the uplift of QinghaiXizang Plateau and the northwards shift of latitudinal zone since the Pliocene. The karst evolutioncan be divided into 3 slages(Fig.3),the first stage:intense karst process,the second stage:coutinning karst process, and the third stage: mechanical weathering and relic karst process.
  • A DISCUSSION ON SOME PROBLEMS OF WINDS AND SANDS AT MOGAO GROTTOES IN DUNHUANG
    Qn Jianjun, Zhang Weimin, Peng Qilong, Li Yuquan, Li Yunhe, Wang Wanfu
    1996, 51(5): 419-425. https://doi.org/10.11821/xb199605004
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    Mogao grottoes have suffered from serious blown sand disasters.In the past half a century,many protective engineering projects were set up early or late in the upper wind areas of Mogao grottoes,yet they were not fully effective because the ways adopted to control sands were unreasonable. Based on the regularities in the motion and the threat of blown sands, this paper is to assess the protective engineering in the past and to discuss the necessity of long-term sand controlling.At last the authors suggest that a protective system of "six belts in a system" shouldh established.
  • EFFECTS OF WATER TRANSFER FROM THE DANJIANGKOU RESERVIOR ON THE MIDDLE AND LOWER REACHES OF THE HANJIANG RIVER
    Shen Dajun, Liu Changming, Chen Chuanyou
    1996, 51(5): 426-433. https://doi.org/10.11821/xb199605005
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    Employing the data from 1969 to 1990, the authors compared the water table and streamflow after heightening the dam and transferring water to north in 2020 with those at eight sites down the Danjiangkou Reservoir.The assessment of the impacts of water transfer from the Danjiangkou Reservoir on the middle and lower reaches of the Hanjiang River,including streamflow process, water tables,navigation and irrigation water use, was done. The results indicated that the annual average water tables and streamflows down the Danjiangkou Reservoir would decrease after water transfer.The runoff process would be more even due to the decrease in flood flow and the increase in dry period flow.The duration of flood streamflow would be shortened,while the duration of dry season streamflow would be lengthened.The diverted water quantity for irrigation in four large irrigated districts would be decreased,accompanying with more serious water shortage.The navigation condition in low-flow period would be improved due to enlargine the regulating capacity of the Danjiangkou Reservoir, but the middle-flow navigation duration would be shortened.Finally,the ideas on the compensating engineering at the middle and lower reaches of the Hanjiang River were proposed.
  • AN ANALYSIS OF THE CHARACTERS OF BLOWN SANDS
    Liu Dayou, Dong Fei, He Daliang
    1996, 51(5): 434-444. https://doi.org/10.11821/xb199605006
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    In this paper, the saltation of sand grains was studied in the case of the steady and fully developed blown sands.It was found that moving sand grains always gain horizontal momentum and mechanical energy from the wind and transfer them down to the bed surface.The features of saltation was analysed in a continuum viewpoint:the particle phase has relatively fast slip velocity on the bed surface,and it has rather strong vertical velocity fluctuation while the average vertical velocity is exactly zero. The vertical velocity fluctuation of particle phase is neither(molecular)thermal motion nor turbulent fluctuation,so it is a new sort of fluctuation which is called PL fluctuation by the authors[6,7]. It was pointed out that this velocity fluctuation is the reflection of particle saltation in the continuum viewpoint, and it plays a rather important role in determining the structure of the blown sand field and maintaining the microscopical balance in this field.In the end,the shear stress corresponding to this fluctuation was discussed:the constitutive relation was given and an important character of this shear stress was discoverd that it is almost independent of the local velocity gradient of the particle phase.
  • THE THEORETICAL FOUNDATION OF REGIONAL SUSTAINABLE DEVELOPMENT──LAND SYSTEM SCIENCE
    Huang Bingwei, Chen Chuankang, Cai Yunlong, Wang Yanglin, Xu Xuegong
    1996, 51(5): 445-453. https://doi.org/10.11821/xb199605007
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    A systematic study on Sustainable Development would depend upon studies on Regional Sustainable Development.The theoretical foundation of Regional Sustainable Development is the comprehensive idea about natural and human factors in the earth──snrface system,that is, Land Systematic Science.The extensive studies on Sustainable Development will not only be one of main jobs of Geography,but also enhance the development of Geography.
  • LANDSCAPE DIVERSITY TYPES AND THEIR ECOLOGICAL SIGNIFICANCE
    Fu Bojie, Chen Liding
    1996, 51(5): 454-462. https://doi.org/10.11821/xb199605008
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    Biological diversity can be studies at four levels of organization:genetic,species,ecosystem and landscape. Although habitat heterogeneity has received increased attention, especially in the agricultural landscape mosaic dominated by monoculture practices,the ecological importance of increasing landscape diversity has not been addressed in a comprehensive approach.Landscape diversity types and their ecological significance are discussed in this paper.Landscape diversity is the complexity and diversity of landscape elements in composition,structure and function, which refers not only to number of different patch types, patch size,and patch shape within a landscape mosaic, but also to the spatial arrangement of different patch types and the connectivity and connectedness of these patches. Therefore,landscape diversity is composed of patch diversity,landscape type diversity and pattern diversity.Patch diversity identifies patch number, patch size, patch shape, perimeter-area ratio,landscape fragmentation and patch edge.Landscape type diversity identifies distribution richness and proportions of patch types.Pattern diversity is a measure of the relative arrangement of patch type within landscape mosaic,which identifies spatial pattern of landscape type,connectivity, spatial linkage and neighborhood effects between the patches.Pattern diversity considers not only physical distance between the patches but also the landscape connectivity.Landscape diversity,including patch diversity,landscape type diversity and pattern diversity,may influence a variety such as ecological phenomena such as species distribution,movement and diversity,water runoff and erosion,nutrient cycling and energy flow rates,biomass and prductivity.Landscape diversity can be related to land use and landscape planning,wildlife habitat protection and biodiversity conservation.In optimizing biodiversity at the landscape level, resource managers and policy makers must not only conserve an array of patches, but also address how these patches can be best interconnected.
  • A STUDY ON APPLOCATIONS OF TEMPORAL GIS IN THE DEVELOPMENT OF CADASTRAL INFORMATION SYSTEMS
    Qiao Yanyou
    1996, 51(5): 463-470. https://doi.org/10.11821/xb199605009
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    This paper explores the issues in the application of temporal GIS in the development of Cadastral Information Systems.Temporal GIS is now one of the most important areas in the development of Geographical Information Systems.Its application can not only facilitate the storage of historical data, but also make the time based analysis of spatial phenomena possible. And it can improve the abilities of dynamic management.analysis and decision-making on geographical information.Cadastral information management, whose data has an archive type structure and changes frequently,is a promising area for the application of Temporal GIS.Some specific issues should be studied before applying Temporal GIS in the development of Cadastral information systems.Boundary point, parcel, point feature and line feature,each with its attribute,are four elementary features in cadastral information management.Date Stamping method is used to build spatiotemporal data structures for each of the elementary features and its attribute.In addition, problems of subdivision and consolidation of parcels are taken into consideration in the building of the data structure.In this paper’s data structure, apart from the identifier, the creating date and the ceasing date,the record of each boundary point records its accurate coordinates and all the parcels whose boundary cross it; the record of each parcel records its composition of boundary points,its ancillary features, its origins and its changing state;the record of each point feature records its coordinates;the record of each line feature records a series of coordinate of points.Through this kind of data structure,all boundary points,no matter when they occur,are stored in one database;all parcels are stored in another database;all point features and all line features are stored in their own databases respectively.Date stamping method is also used to build data structures for attribute databases,so that all attributes of all boundary points,all attributes of all parcels, all attributes of all point features and all attributes of all line features are stored in their attribute databases respectively.Updating and querying procedures are taken as examples to study the accessing and applications of the data types in this paper.When a feature ceases to exist,the database can be updated by simply adding the ceasing date to the related records.If a feature has changed into some other features,apart from adding ceasing time to the old record,several new records should be inserted to record the new features.Based on this kind of data structure,querying can bedone in the time dimension as well as in the space dimension and the attribute dimension.The results of this paper have been found successful in the development of the Cadastral Information System for Langfang in Hebei Province.
  • AN INTEGRATION OF GIS AND ANALYTICAL MODELS FOR EVALUATION OF DISASTERS CAUSED BY MOUNTAIN TORRENTS
    Zhao Shipeng
    1996, 51(5): 471-479. https://doi.org/10.11821/xb199605010
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    Mountain torrents is a kind of flash floods which bring about a great loss of life and damages of properties in mountainous area.in order to support decision making on disaster reduction and prevention,it is necessary for us to evaluate disasters of mountain torrents quickly and correctly. The difficulties in evaluating disasters of mountain torrents lie in the impossibility of hydrologic observation by conventional method because of the grest flowing velocity and washing force and the insufficiency of information got by remote sensing method because of the short duration of mountain torrents.In order to overcome such difficulties,a new method which is an integration of GIS an analytical models is explored in this paper.what we use is an external integration method,i.e.the analytical model is integrated with GIS system as an external procedure.In the process of evaluating disasters of mountain torrents,the role of GIS is to transform vector data into grid data and to query,access,display and analyse grid data;the role of analytical model is to simulate behaviors of water and sand within grid and among grid and to determine the disaster class for each grid.The procedure for evaluation of disasters caused by mountain torrents is as follows:firstly to establish a database including data collection,map digitization and input of tabular data;secondly,to analyse data including DEM analysis,analysis of drainage network and rastering;thirdly,to run the model which includes sekction of simulation parameters,simulation of flood and simulation of sand transprotation within the watershed;fourthly,to evaluate disasters which includes calculation of washing forces,analysis of disaster──bearing capacity and determination of disaster classes.Taking mountain torrents in the Sunhugou watershed on Aug.10,1969 as an example.we tested this methd.The result showes that integration of GIS and analytical mdel is an efficient method for evaluating disasters caused by mountain torrents.GIS promotes establishment of distributed hydrohgic model by management of spatial data; analytical model extends function of GIS by provision of hydrologic information such as water depth,flowing velocity and sedlment concentration.Compositeness of spatial ad temporal information in GIS is an important part in evaluating disasters caused by mountain torrents.Formation of disaster by mountain torrents is a dynamic process in which sufficient information can be got only by simulation of water and sand behaviors.Efficient management and output spatiotemporal information are a subject that need be further studied in GIS.