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991.
LIntroductionSeaIevelnse(SLR)isacertainresu1tcausedbyclimaticwampandunreasonableanthropogedcaCtivities,itwillbringaboutaseriesofnegaivethesonenvironmentalevoltalonandsocio-econonucdevelopmentincoastalarea.Cboaisavastcowtrywithl8,OOOkmand14,OOOkmofcontinentalandislandcoastlinesrespeCtively.Over3Ohaddleandbigcitiesandneariy2Oimportantharbours,includingTianJin,ShanghaiandGuanghouarelocatedinthecoastalareawhere4lpercentofthenation'spopulahonandoveY5operedofGNP(GrossNationalProduCt)iscon…  相似文献   
992.
SeasonalTransitionofSummerRainySeasonoverIndochinaandAdjacentMonsoonRegionJunMatsumotoDepartmentofGeography,UniversityofTokyo...  相似文献   
993.
Although great-progress has been made in the earth sciences,some fundamental problems of geodynamics remain unsolved.They are concerned with the whole earth as well as regional tectonics,such as the west Pacific and Qinghai-Xizhang plateau.The new generation of earth observation by space-based measurement will contribute to solving these problems of geodynamics.In this regard,some specific plans about application of these techniques are suggested in this paper.  相似文献   
994.
In this work,the fractal dimension of granulometric composition in the fault gouge from the Yishu fault zone and northwest-trending faults on its west side is calculated and studied based on the fractal theory of rock fragmentation.The seismo-geological implications of the fractal dimension of granulometric composition in fault gouges are also discussed.The results show that the Yishu fault zone is more active than the northwest-trending faults and the Anqiu-Juxian fault is the most active in the Yishu fault zone.The fractal dimension of fault gouge is a parameter describing the relative active age and rupture mode of the fault and forming age of the fault gouge.The fractal dimension value is also related to the parent rock,thickness,structural position,and clay content of the fault gouge.  相似文献   
995.
The northern Liulengshan piedmont fault is located along the southern margin of the Yangyuan basin and represents a dip-slip normal fault,generally NEE-trending and NNW-dipping.Landforms offset by the fault are fairly developed and well preserved in the Dushanpu area of Yangyuan County,Hebei Province.Two trenches were excavated in front of a scarp of the northern Liulengshan piedmont fault at Dushanpu and two paleoseismic events were revealed in the trenches,from which several samples were collected for dating.The samples were dated using the IRSL dating technique.The preliminary result shows the possible ages of the two paleoseismic events.  相似文献   
996.
I.llltr0dtlch0n~studyhasshowedU1atiI1filtrationdePa1dsnot0nIyOnsoiIpIDpeIty,alndatln0iStLle,lainfallproPeltiesbutalsoonSu1facel1liclDtopographicprope1ties,sud1assudecesloPegradia1t,vopalcoverandlandtItiIization.n1etheofh1efonnerelelna1tsol1infiltrationhas…  相似文献   
997.
微波波段大气的衰减作用之实验研究   总被引:1,自引:0,他引:1  
本文研究了微波波段(λ=5mm-3.2cm)大气的衰减作用。用微波辐射计,根据太阳射电法和大气辐射法进行大气微波吸收值的测量,同时用探空记录计算大气微波吸收值,两者进行比较和分析它们的相关。本文研究了大气微波吸收值与大气总水汽含量或地面气象要素(如温度、比湿)之间的关系,提供预告大气微波吸收值的可能性,云层对于大气吸收值的影响,文中也作了讨论。  相似文献   
998.
The absorption characteristics of the atmospheric window in the microwave band (λ=8.5 mm and 3.2 cm) are studied. The results measured in Beijing by using both solar radiation method and atmospheric radiation method arc compared with the values calculated from the radiosonde data so as to analyze their correlativity. The relationship between atmospheric window absorption and total column water vapour content is also discussed. The effects of clouds on the absorption are described.  相似文献   
999.
bnP0ItaIlce0fShIdyolILaIldUsealldLalldC0veI'CIlangef0l'GI0balCIlallgeResealtIlSttldyollland[Iseandlandcoverc1lange(LULCC)isOI1eoftnein1portantareasforullderstandingregionala11dgl0balellvironllleIltalconseqLIences.A1tno[lglllandcoversocQlPyonlyone-thirdoftneeartn'ss[lrface,tneland[lsePatter11andn[ln1analternations0flandcoverllavein1pofta11tin1Pacto11gl0bal-scalecnangnoftneclin1ate,bi0gnocnen1istry,nydrology,andbiodiversityofeaIthSystenl.TneI1eterognneityoftllelandsurfaceinterlnso…  相似文献   
1000.
I.Introducti0I1Hail1al1isthelargnsttropicalislal1dwitllabundal1t11aturalrcsourccssuitablef0rgrowtllgtrol,icalcropsand\\4t11ven'highp0tentia1pr0d,uctivity.Hotx'cY'cr,t11c1-ca1'cstillsomeproblemsf(l)Tl1ese1ectionoflandsuitableforfqrestisn0tstrictalldPreservativerateoftr0picalcr0psislow,(2)Mostoftropicalcr0psarecollccntratcdillthezoneofeastern"windgap"andnorthern"frigidplace"andtheirsecurityisnotstable,(3)Rubberareaaccountsforab0uttwo-thirdsoftl1etotalarea0ftropica1crops,henceproportiondis1ocat…  相似文献   
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