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1.
Zhu Dexiang 《地理学报(英文版)》1995,(3)
TheNanshalslandsarethesouthetnmostterritoriesinChina.TheIslandsconsistof230islands,redandbeaches.Inthehistoricalperiod,theChineseancestorsovercamedifficutiesandfOundtheIslands2,0OOyearsago.Agreatmanyofhistoricalliteraturesindicatethatheeariiestrecords,mpa… 相似文献
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TheLoessPlateauarealocatedinti1eMiddleReachesoftheYellowffiver(MRYR)isti1ecradleoftheCltinesenationandthesourceoftheancientcivilization.However,dun11galongpenodoftime,unreasonablelanduse,rapidpopulationgrowthandsenousmptiol1damagemadetheoriginalcriticaIenvirorunentevenworsened,deePlyichuencingtheeconowhcdeveloPmrmandtheimProvementoflocalpeople'slivingstandard.Thege0graplticalenvirorul1entisaco11unonandnecessaryextemalcondition.Wthsocialprogressandsciatificandtechnicaldevelopn1Cnt,theconn… 相似文献
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I.IntroductionTlleYangtzeXiveroriginates0nthenorthernsideoftheTananlaMoulltail1ns0lltheQinghai-TibetPlateauinsouthwesternpartofQinghaiProvince,traversingacrosseightprovincesandanautonomousregionandfinallyPOuringintotheEastChinaSea.The638O-kilollleter-l0ngYallgtzeXivercoversadrainagearea0fl.8mi1lionkin'.0fthe53firstclasstributaries,26haveadrai1lageareaexceedinglO,OO0km2each.lnthevastdrainageareaoftheYangtzemver,tl1eeco-envir0nmentalconditi0nsdiffergreatlyfr0m0neregiontoan0ther.Topograp… 相似文献
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1.1ntroductionVolcanosofMt.Unzen-dakeinJapanandMt.PinatubointhePhilippineseruptedoneafteranotherduringthefirstandsecondtendaysOfJunel99l.ThevolcaniceruPtionindex(VEI)ofMt.Pinatub0withgrade6isthehighestoneinthesCenury[2].Inl99l,rainyseasonadvantalintheYang… 相似文献
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MERCURY CONTAMINATION OF FISHES IN THE SECOND SONGHUA RIVER OF CHINA: PRESENT AND HISTORY 总被引:1,自引:1,他引:0
ZHANG Lei WANG Qi-Chao SHAO Zhi-Guo 《湿地科学》2005,3(1):27-31
1 INTRODUCTIONIntherecentyears,exposuretoenvironmentaltoxinshasreceivedincreasingattentionasthepublicadverseeffectcausedbytheirtoxicity .Mercuryisoneofmosttoxicmetalsintheworld .Manyre searcheshaveprovedthattheconsumptionoffishesmercurypollutedisthemains… 相似文献
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《The Professional geographer》2013,65(3):278-282
The effects of intra-farm distance on farm income have not been previously tested in North America. European studies are inconclusive as they use data taken from bookkeeping accounts for the farm as a whole. This paper calls for field-to-field farm analyses that combine internal movement costs with costs of production, yields, and farm-gate prices. In a study applying this method to Manitoba grain farms, it was found that adjustments in the organization and intensity of farming offset the effects of distance on net income. 相似文献
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Ding Dengshan Bao Haosheng Department of Urban Resources Sciences Nanjing University Nanjing People''s Republic of China 《地理学报(英文版)》1997,(4)
Atpresent,theMiddleEastisaregionoverwhichmanykindsofcontradictionsexist.Itisobviousthattherootcauseliesinitsimportanceinthestrategicgeographicalpositionandrichresourcesofoilandnaturalgas.Ithasalwaysbeenahotspotintheworld,andconflictshaveoccurredthereco… 相似文献
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Wu Shengguang Yang Dayuan Department of Geography Nanjing University Nanjing People''s Republic of ChinaWang Yunfei Nanjing Institute of Geography Limnology Academia Sini Nanjing People''s Republic of China 《地理学报(英文版)》1997,(2)
I.TheTerracesoftheUpperYellowRiverTheterracesoftheupperYellowRiveraremostlydispersedalongthewidercoursesinseveralMesozoicCenozoicbasins(Figure1).1.TerracesbetweenNgoringLakeandGyaringLakeThesurfacelayersofthesedimentinthewideandshallowbasinswheretheYell… 相似文献
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ZulkifliNasution MashhorMansor 《湿地科学》2004,2(2):104-109
Situated at an elevation of 905 m above sea level in the Province of North Sumatra, Lake Toba and its surrounding landscapes are regarded as a natural heritage in a certain extent, as a quoted national treasure. Unfortunately degradation of the land and water resources in the watershed along Lake Toba is taking place at an alarming and totally unacceptable rate. The quality of the lake is partly depended on input the quality of the rivers. When compared to the control area the water quality that influenced by the piggeries are highly polluted. It can be concluded that the Salbe River at the downstream of the piggeries has been polluted and apparently it is a serious problem to the catchment area management. It should be noted that the polluted river would influence the water quality of the Lake Toba. Based on calculation, the permissible BOD5 according to B- river standard is 238 mg/L, it means the river still in B standard but the condition and quality are decreasing continuously. Following the Indonesian health standard the permissible BOD is - 461 mg/L. It means BOD in the river should be reduced 461 mg/L or clean program is needed. 相似文献
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《地理学报(英文版)》1978,(1)
SYNOPSIS For the sake of flood and sedimentation control down-stream of the reservoirs, a study has been carried out on the ways of operation of several reservoirs in the Lower Yellow River. A program on the regulation of flow and sediment is suggested with the following purposes: 相似文献
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《The Professional geographer》2013,65(4):393-398
The United States Department of Energy is required by law to plan, acquire, store, and maintain a Strategic Petroleum Reserve of crude oil and petroleum products. This is to be used if there is an interruption in crude oil supply. The plan is described and then analyzed with a linear programming model. The results show that the plan is generally well formulated. 相似文献
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《地理学报》1978,(1)
SYNOPSIS For the sake of flood and sedimentation control down-stream of the reservoirs, a study has been carried out on the ways of operation of several reservoirs in the Lower Yellow River. A program on the regulation of flow and sediment is suggested with the following purposes: 相似文献
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Tian Hong 《云南地理环境研究》1999,(Z1)
1 BackgroundXishuangbannaDaiPeopleAutonomousPrefectureislocatedinthesouthernpartofYunnanProvince,China.Thetotallandareais19223km2withpopulationof817772ofwhichareDai,Hani,Bulan,Lahu,Jinuo,Yao,Wa,andHanpeoplein.Theforestcoverageis63%.Thereareabout40000… 相似文献
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The Problem of studying eomPlex multicomPonent systems without seParation of theeomPonents 15 well known.Generally,the situation arises whenever interaetions betweeneomPonents are essential in determining the funetion of the system,notably in biochemiealsystems and in eatalysis.In eases sueh as these,the ultimate aim 15 to deduee the role of eaehof the eomPonents as well as the interaetions between them by 相似文献
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《The Professional geographer》2013,65(4):412-415
Recent federal court decisions have emphasized the need to eliminate schools whose racial composition varies from that of the whole district by more than a fixed percent. A linear programming model is presented to assist school administrators in developing desegregation plans that comply with these guidelines. An efficient solutional technique that exploits the special structure of this model increases problem-size capabilities. A study of the Columbus City School District examines the tradeoffs involved at different levels of desegregation. 相似文献
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Li Wenyan 《地理学报(英文版)》1996,(3)
I.Introductionl.BasicfcatUresofportcitiesandthcirwhuencingfactorsTl1elhstoricalexperiencesofdevelopedcowtrieshavewitnessedtheessel1tialro1eplayedbyseaportsinpromotingdevelopn1entofnationaleconomy.Manyportcities,emergodfron1marinetransportation,supportedbyseaandlandroLrtesandflourishedn1ainlythroughindustryandtrade,oftenbecomendonalornationalecononhccenters.fu11ongti1eworld's2Omeqalopolesofmorethan6ntilIionpopulation,l2areportcities.AlmosteverycoUntrywiti1coastalline,longorshort,roprdsoneors… 相似文献