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1.
THECONSTRUCTIONANDITSDEVELOPMENTOFTHEOVERSEASTRANSPORTSYSTEMINNORTHEASTCHINAGaoShali(高莎丽)(DepartmentofGeography,NortheastNorm...  相似文献   

2.
Based on the fractal theory, the spatial structure of China's vegetation has been analyzed quantitatively in this paper. Some conclusions are drawn as the following. 1) The relationships between size and frequency of patch area and patch shape index exist objectively for China's vegetation. 2) The relationships between perimeter and area exist objectively for China's vegetation. 3) The fractal dimension of evergreen needleleaf forests on mountains in subtropical and tropical zones is the largest, while the smallest for deciduous broadleafand evergreen needleleaf mixed forests in temperate zone, reflecting the most complex spatial structure for evergreen needleleaf forests on mountains in subtropical and tropical zones and the simplest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone. 4) The fractal dimensions of China's vegetation types tend to decrease from thc subtropics to both sides. 5) The stability of spatial structure of deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone is the largest, while the smallest for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards, reflecting the steadiest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone and the most unstable for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards in spatial structure. 6) The stability of spatial structure of China's vegetation tends to decrease from the temperate zone to both sides, it is significantly pertinent to understand the formation, evolution, dynamics and complexity rule of ecosystem of vegetation.  相似文献   

3.
1INTRODUCTIONMandelbrot stated the uncertainty of the length of a coastline in his paper "How long is the coast of Britain? Statistical self-similarity and fractional dimension" pub- lished in Science in 1967 (MANDELBROT, 1967). The concepts of fractal and fractal dimension were presented for the first time in that paper and have been applied to quantitatively describing the difference of crooked coastlines of British and South Africa. Compared with the Euclidean geometry with more…  相似文献   

4.
Traffic network is an importance aspect of researching controllable parameters of an urban spatial morpholo-gy. Based on GIS, traffic network structure complexity can be understood by using fractal geometry in which thelength-radius dimension describes change of network density, and ramification-radius dimension describes complexity andaccessibility of urban network. It is propitious to analyze urban traffic network and to understand dynamic change processof traffic network using expanding fractal-dimension quantification. Meanwhile the length-radius dimension and ramifica-tion-radius dimension could be regard as reference factor of quantitative describing urban traffic network.  相似文献   

5.
Fromtheendofthenineteenthcenturytothebeginningofthetwentiethcentury,Davis(1899)providederosionalcirculartheory,tookgeomorphiccharacteristicsasthefunctionsoftectonicforcesandtime,dividedgeomorphicgrowthintothreephases:young,middleagedandold,andthenra…  相似文献   

6.
根据分形的性质,构造了一个新的分形图形,它的豪斯道夫维数是log5/log3,研究了给出的分形图形的两种算法。  相似文献   

7.
The northeast region is one of the principal mire distribution regions in China. According to the process of peat formation and accumulation , middle geomorphology type controlling water source supplement and the plant cover, 2 types, 10 subtypes and 27 mire bodies are divided. The mire area decreases gradually from north to south. There is more peat mire in the mountain and there is mainly gley mire without peat in the plain. The paper also explains the mire types in the principal mire distribution region and the utilization of mire in the fields of agriculture, forest, animal husbandry. The mire is a wetland ecosystem. It can reserve a lot of water, adjust rivers, humidify air. Thereby , attention must be paid to protecting ecological balance in the process of reclaiming mire and the mire protection.  相似文献   

8.
Land-cover survey in northeast China using remote sensing and GIS   总被引:1,自引:0,他引:1  
I.INTRODUCTIONWiththerapiddevelopmentofnationaleconomyandthegrowthofthepopulationsincethe1990s,therecomesnewdemandsforexploit...  相似文献   

9.
I.~~IC~acacomeNacacomenawoadsiN~chIcInChinawiththeimplementofthestrategyofoverallopeninguptotheoutsideworld,NortheastChinahasbasicallyformedanopenpatternwithsimultineousdevelopmentofborderopeningandcoastopening.Althoughthecoastopeningissmallerindegree,theherderopeningtakesanimnytantPOsitioninChina.Borderopeningandcoastopeninghavedifferentdirections,presentingthefollowingaspects.First,asfortheopeningaim,borderopeningaimstoutilizefrontiersuperiorityonthebasisofequalityandmutualbenefit,tofor…  相似文献   

10.
Wetland is a special ecological system in the earth, which can provide a good habitat for many wild animals. It is a reproduction and overwintering area for many rare waterfowls, too. The northeast region, including Heilongjiang, Jilin, Liaoning provinces, and the east of Inner Mongolia, is a district with the maximum areas and types of wetlands in China. It is the center of the waterfowls reproduction in Northeast Asia and the necessary region moving to the south. The conservation of wetland and waterfowls habitats in northeast China plays an important role in international waterfowls habitats conservation. The northeast weterfowls’ types, number and distribution specific features are studied in three aspects in the paper, so do the rare waterfowls. Existing problems and the administration polices on waterfowls and their habitats conservation in the northeast are also discussed. It shows that the conservation of wetland waterfowls habitats in northeast China is important.  相似文献   

11.
Conservation of wetlands especially as waterfowl habitat in northeast China   总被引:2,自引:0,他引:2  
Wetland,withveryhighbiologicalproductivity,tremendousresourcepotentialandenvironmentfunction,isaspecialecosystemintheearthan...  相似文献   

12.
为对比基于含水饱和度和汞饱和度2种方法计算低渗透碎屑岩储层孔隙结构分形维数的优劣性,分别采用2种方法对川中地区须家河组41块储集岩的毛细管压力曲线进行分形维数计算.结果表明:采用汞饱和度计算的孔隙结构分形维数与排驱压力、分选因数等表征储层孔隙结构的参数相关性较好.随着岩样分形维数增大,排驱压力增大、分选因数减小,相关性明显.采用含水饱和度计算的孔隙结构分形维数与排驱压力、分选因数等相关性较差.在条件许可时,可利用恒速压汞实验计算储集岩孔隙结构分形维数.  相似文献   

13.
Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions.  相似文献   

14.
At the study area of Xigu District in Lanzhou City, using RS & GIS as tools we apply Diversity, Dominance, Fragmentation, Isolation and so on to study the quantitative, fractal and spatial characters of landscapes structures in the four sub-regions divided by the morphological features. Using the Fractal Theory to establish the fractal structure models, we analyze the complexity and stability of various landscapes distribution with fractal dimension value. The spatial distribution characteristics of landscape mosaic structure are also expounded. At the end of the paper we discuss the relevant problems on the main factors which control and effect on the spatial pattern of landscapes as well as on landscape optimization and management. Foundation item: Under the auspices of the National Natural Science Foundation of China (No. 40171069). Biography: XU Jian-hua (1965 - ), male, a native of Gansu province, professor. His research interest includes Geo-computation and GIS.  相似文献   

15.
Fractal theory was applied to a preliminary discussion of the fractal character and formation mechanism of the coastline of the bedrock coast of China on the basis of GIS ( Geographical Information System). Some significant conclusions were drawn : ( 1 ) The fractal dimensions of the coastline and linear structures of Liaodong Peninsula are 1.0093 and 1.0246 respectively, those of Shandong Peninsula are 1.019 and 1.021 respectively, etc. (2) The fractal dimensions of coastlines of Liaodong Peninsula, Shandong Peninsula, Zhejiang and Fujian-Guangdong tend to increase with the spatial change from north to south. (3)The regional linear structures( including faults)control the basic trends and fractal dimensions of coastlines as a whole in the regions of the bedrock coast of China : the more the controlling effect of linear structures, the smaller the fractal dimensions of coastlines. (4)The substantial constituents of coast and biologic function both play an important role in affecting the fractal dimensions of coastlines of Liaodong Peninsula,Shandong Peninsula, Zhejiang, Fujian-Guangdong and Taiwan Island.  相似文献   

16.
江西省新余市城镇体系分形特征的研究   总被引:2,自引:0,他引:2  
相对于传统的规划方法对城镇现状条件难以进行科学量化的局限性,一些现代数学理论与方法对提高城镇体系规划成果的科学性与准确性方面有显著的促进作用。本文应用分形理论,对新余市城镇体系的规模结构和空间结构的分形特征进行了实证分析,通过构建分形特征的数学模型计算了新余市城镇规模结构的分形维数、空间结构的聚集维数和关联维数,分析其分形结构特征,最后得出新余市城镇规模不均衡,城镇联系不紧密,城镇体系功能未能充分发挥的结论。在此结论基础上根据新余市的现实条件,对新余市城镇体系规划及发展提出了改进建议。  相似文献   

17.
This paper brings forward the concept of stability of the spatial structure of urban agglomeration(UA)based on Central Place Theory by introducing centrality index and fractal theory.Before assessment,K=4 is selected as parameter to calculate centrality index and fractal dimension(K represents the quantitive relationship between city and the counties in Central Place Theory),and then found the number of nodes,the type of spatial structure,the spatial al-location of nodes with different hierarchy affecting the stability of spatial structure.According to spatial contact direction and the level of stability,UAs in China are classified into five types.Finally,it is posed as a further question that how to use hierarchical relation K=6 and K=7 in central place system to coordinate with the assessment of stability of spatial structure is brought forward.  相似文献   

18.
I.INTRODUCTIONMostvolcanoesaredistributedinnortheastofChina.Thevolcaniceruptionscanchangethegeneralmorphologicconfigurationof...  相似文献   

19.
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper “How long is the coastline of Britain?” published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method, the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China‘s Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China‘s Mainland, and it does not vary with the changes of series of square grids, the fractal dimensions of the mountains of China‘s Mainland are different with these changes. 2) The fractal dimensions of the mountains of China‘s Mainlandvary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China‘s Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension, and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China‘s Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China‘ s Mainland. The research is helpful to get the more understanding of fractal and fractal dimension, and ensure that the fractal studies would be scientific.  相似文献   

20.
MODUrnONTheS0uthChinaSea(SCS)isabophalrnarginalbasinwhereEastAsiamonsoonsprevail.0bviousadjustInentSoftheupperocanoccurduetOthealtematingsurnxneandwintermonsoons.ThemostboohantaspchoflargeanlecurmtSintheSesaretheupperoonnicresponsetothemonsoons(Dale,l956).MostpreviousmrehesfocusedondiagnostiesandmodelingofsuffocecurmtS.Wwti(l96l)plotalsurfacentsbasedonshipdriflsintheNAGAReportNo.2anddescritaltheperiodicallysdri-annualreversingofwindsandrtinthisarea.Xuetal.(l982)calculatalthedy-naAn…  相似文献   

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