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1.
IIWr~IOWThesedimentarycharacteristicsofdebrisflowcanreflectthecompoSition,fluidtypeandsedimentaryprocess.ThescholarswhostudymoderndebrisfloWinChinagenerallyclassifydebrisflowbythemethodofviscositywithfloWpattern.SeveraltypicalschemesareshowninTable1,inwhichthemethodofunitweight(fluiddensityinunitvolumet/m3)isusedandfluidunitweightisthoughttobethedirectproPOSitiontotheviscosityofdebrisflow(Wu,1990).Ithasbeenprovedbyhydrcrmechacsthatnon-cohesivedebrisf1OwfollowsBagnoldgranular'flowmedel(B… 相似文献
2.
rmDUCnONInthecultUreofbenthicdiatomsasfeedforabalone,itisnecesoptoaddsomnu-trientssuchasnitIngen,Phosphorus,ironandsilicontotheSeawatermwhum.Thecom-monraioofthenutrientswas(lO-25):(l-2.5):o.l:l(mg/L)(Chenetal.,1977).Anstinetal-(l99o)rePOrtedthatheratioofnibogenandphosphorusinfluencedthebio-massdensityofthePeriphyton,whichInainlyconsistedOfbenthicdiatomPOPulations.However,theirrestiltswerenotbasedonmonoalgalwwh,andtherewerenodetallsonthereasonableratioofthesenutrientsintheirreports-Ther… 相似文献
3.
unODUcrIONIntereStinthecarboncycehasinamsedbouseoftheobservedincreaseinatmosphericCO,leveIsduetothebumingoffossilfuelandthedearingofforestsre-sultinginlargedhaticandbiogeochdrica1consequenas(ChenandDrake,l986).Experi-mentalstudisofp1antShaveshownresponsesoftypically2O%-4O%highergroWthunderdoubledCo,conditions.Ontheotherhand,theeffedofelevatalCO=conditionsinincreasinggroWth,knownastheCO,fertilimtioneffed,isnotbe1ievedtobetwortantintheoasns(Schimeletal.,1995).Althoughithasbeensuggestedt… 相似文献
4.
lINrnoDUCnoNConidorsaresPecialpatcheswithnarrowandlongshaPe,andoftenhavethefunctionsastransPOrtation,protection,resomeesandaesthetics(FoRMAN,l986;ALMO,l998).Conidorsconnectvariouslandscapesbytransportingmaterials,energyandinformation.NewconidorscreatedbyhumanactivitiesareimPortantfac-torsleadingtolandscapefragZnentation.Inthemean-while,theyarealsobanierstothecormectionsofdifferentecosystems(WANGetal-,1996).Theconi-dorshavefrhoentedthelandscaPe,andchangedtheoriginalsituationofthenatu… 相似文献
5.
ChntnbutionNo.3127fromtheInstituteofOceanology,ChinereAcademyofSciences.Project39370542supportedbyNSFCandstudyalsosupportedbyNationalKeyLaboratoryintheInstituteofHydrobiology.ChineseAcademyofSciences.lNTRODUCTIONltisknownthatgroWthrateoffishcanvary'inresponsetotemperatureandfoodavailability-andperhapslessobviously,tolight,oxygenandothervariables.ThispropertyofvariablegroWthinfishcanbereferredtoasplasticity(Weatheriey,l990).TheeffeCtSofenvironmenta1thCtorsongroWthcanbepredictalfor… 相似文献
6.
王景华 《中国地理科学(英文版)》1992,2(4):357-366
The background values of Cu, Zn and Ni are discussed based on the analytical data of 21 main soil types collected from various regions in China. According to statistics of many samples, the background value of Cu is 23.4±10.2 mg/ kg (482 samples), Zn 77.9±2.39 mg/ kg (474 samples), Ni 30.0±12.8 mg/kg (482 samples). 相似文献
7.
《中国海洋湖沼学报》1985,(1)
In this paper the influences of short-term wind on vertical structures of temperature and salinity, and the upwelling off the Zhejiang coast are studied on the basis of hydrographic data and wind near the coast in Summer (1959-1979). It is pointed out that the variations of vertical distributions of temperature and salinity, and upwelling in this region are closely related to short-term (several days to a week) variation of wind observed. The occurrence of double thermocline, a special oceanographic phenomenon, is partially related to unstable SSW wind field. SSW and NE winds in June are two (dynamic factors making intermediate warm water form or disappear. 相似文献
8.
The experimental results showed that:1) The embryonic development of bay scallop is inhibited ata dissolved oxygen range of 1.38-3.64×10~(-3)at 23℃,and completely blocked below the lower limit.2)The tolerance of larvae to anoxia increased with larval sizes and was related to their oxygen debt.3)The scallop larvae exhibited specific behavioral responses to oxygen deficiency,which finally led tovelum disintegration and larval death.The possible relationship between environmental oxygen deficien-cy and the disease of disintegration of the larval Velum is also discussed.In this study,considerableoxygen debt was found in bay scallop larvae,which was greater in small animals.Based on the worksof previous authors,a new concept is proposed for the estimation of oxygen debt,namely,thecompensatory rate of oxygen debt(CROD).This can be used in intra-or interspecific comparison ofoxygen debt.The results can be helpful in the management of water quality and for the prevention oflarval diseases encountered in scallo 相似文献
9.
The effects of recombinant eel growth hormone (reGH).methyltestosterone (MT)and L-thyroxine (T4)on the growth of red sea bream. Pagrosomus major.were investigated.Administration of reGH to fry by immersion at 2 mg 1 for 2 hevery 5 dsys resulted in significant increase in both weight and length.but the condition factor (CF) diminished relative to that of similarly treated controls over the 37day treatment period.Immersion in 0.1 mg:1 T4 also resulted in significant increase in both weight and length and higher survival rate of test fry compared to the controls. Immersion in MT had less effect on growth and high-dose resulted in high mortality.In the second study.injection of 2 μg reGH(gwk)caused a significant increase in the specific growth rate (SGR) of test red sea bream fingerlings relative to that of the controls during the 4-week treatment period and maintained the increasing trend over the post-treatment period (weeks 4-6).Injection of MT at a dosage of 1μg (gwk) resulted in a significant in-creas 相似文献
10.
TheQuaternalypaleo--environmentoftheLushan,HuangshanandTianmumountainsisasignificantacademicproblemtowhichmuchattentionhasbeenpaidbymanyresearchersingeosciencecircle.Manyscholarshavestudiedtheproblemandgotalotofachivementsoverthepastyears(Lee,1933;Lee,1936;Lee,1947;Ren,1953;Huang,1963;Li,1974;Shi,1989).HOWever,identicalviewsandconclusionshavenotbeenreachedyetuptillnow,especiallylackingofcomprehensivestudyforsedimentsintheseregions.Inrecentyears,applyingsedimentalcomprehensiveindexgotfromv… 相似文献
11.
ZHANG Luo-cheng ZHU Tian-ming YAO Shi-mou 《中国地理科学(英文版)》2005,15(4):309-314
1IN TR O D U C TIO NC hina, as a developing country, is experiencing rapidpopulation grow th and land expansion,w hich has gen-erated considerable governm entalconcernsand scholar-ly attention (FA ZA L,2000).R esearchers have revealeda m assive increase i… 相似文献
12.
unomicrroNTherearereportedstudisoninorganicsulfurcomPoundsinrnarinesedtritS(Song,l99(),Stefan,l994),butfeWonorganicsulfurcomPounds.Itwasshownthatthroughoilspthe,mnoffandatmosphdriproasses,manyanthropogedcorganicsulfurcomP0undsrnaybethenspotalintothemarineenvirorstWheretheycanbeeventuallydePositalalongwithnatamlorganicstilfUrcomPoundsinseddritSraateSetal.,l979).ResearchesonorganicstilfurcomPoundsinrnarinesedirnentSareofpotentialenvirornnentalchdricalshoilicanceforhaherunderstandingofthege… 相似文献
13.
《中国地理科学(英文版)》2000,(3)
Modern tourism in China began in 1978(DENG,1994), so far, it has a history of nearly 20 years. A clear trend line has appeared in embryonic form in statistical data on overseas tourists. There is a strong need for theoretical studies. This research paper introduces the concept of tourism background trend line and explores its functions in demonstrating fluctuations in the tourism economy ( barometric function) and in forecasting future tourism development (forecast function). 1 THE CONCE… 相似文献
14.
COPPER ACCUMULATION AND TRANSPORT IN A MARINE FOOD CHAIN COMPOSED OF PLATYMONAS SUBCORDIFORMIS, BRACHIONUS PLICATILIS AND PENAEUS MONODON 总被引：2，自引：1，他引：1
mooimON~ofheaVyInetalpollutantsonmarineorganismswereextenSivelystudedguiAgenetal.,l99l,LiuFayietal.,l988,PatinS.A.,l982).bouseofthemarineansySteIncomPlexityandthevarietyofthefoodchain,pollutantSaretIanspondindiliferentwayS-Therefore,studyofthetIansPortofPonutantsinthefoodchainhasdrawnmuchattention.TherearerePortSontheaCCUInulatinnandusnsportofsorneradi0nuclidesguiFulongetal.,l984)suchasCs,Co,andZnandsometIaceelernentSsuchasV,SeandNinthernarinefoodchain(Mthemand,Ctal.,l98O;Unsal,… 相似文献
15.
CHEN Bao-ping ZHANG Jian-chun 《中国地理科学(英文版)》2006,16(2):109-115
1INTRODUCTION Soil and water loss in the Dabie mountainous area is one of the most severe environmental problems in Anhui Province and the Changjiang (Yangtze) River basin as well.Itnotonlyresultsinenvironmentaldegradation,but alsorestrictstheproductionoflocalindustryand agricul- ture and hinders the sustainable economic and social de- velopment of the area, which has done great harm to the people's life and production there (XU, 2000; ZHANG and SHI, 2001). Since the 1980s, especial… 相似文献
16.
I.areanDIppICOrISS~csaiSN~~acomLOnareNTor~INP~CTIOWiNchIcThankstotheOpeningandreformefforts,China'snationaleconomyhasrapidlygiDdy,withitSaverageannualGNP(grOSSnationalpnduct)~hratereaching~9.8%duringthePened1978--1994(StateStatisticalBureau,1995).Thenext30yearsareexpeCtedtowitnessfasteCOnondcgrowthinChina.AsshoWnbytheresultsofourinvestigationS,uptOthecoddleofthenextcenttirywhenChina'spopulationbasicallyceasetO~,agricultUre,eSpedallygrainproduction,will~eavulnerableandweakli… 相似文献
17.
1INTRODUCTION The ubiquitous distribution and known toxicity of lead pollution in urban environment are posinggreat concern, in term of human health and environment (JULIE and ALEX, 2001). In recent years various human activities, such as automobile exhaust, waste disposal, paint, lead smelting and refining, battery disposal, as well as coal and fuel combustion have implied notable contributions to the increase of environmental lead concentration (SUTHERLAND et al., 2003). Pb is an… 相似文献
18.
ImODUcrIONThetermphlorotanninswascoinedbySattlerinl974(dtalinRagan&Glombiha,l986)forthebrownalgalpolyphenoIshavingcheAncalcharacteristiesoftannins.Later,theirstmCturalunitwasprovedraaganandGlombitsa,l986)tobephlorogludnol(i.e.l,3,5-trihydroxybename).OginoandTaki(l957)notalthattheaqueousextraCtSoffreshthalliofSargassumringgoldianumhavetanninproperties(tumingbluishorreddishvioletafteradditionofironsaltS,astringenttaste,andabilitytopredpitategelatin).HighmolecularweightpolyphenoIsfromAsco… 相似文献
19.
Taking South Lake and Jingyue Pool in Changchun as examples,we determined particulate Hg in ambient air and Hg concentration in precipitation.Results indicated that particulate Hg in air and Hg concentration in precipita-tion in both sites in nonheating period were lower than that in heating period,which is influenced by coal combustion.The annual particulate Hg concentrations in precipitation were 0.268μg/L(South Lake)and 0.108μg/L(Jingyue Pool).The high-er particulate Hg concentrations in precipitation were 0.268μg/L(South Lake) and 0.108μg/L(Jingyue Pool).The high-er particulate Hg concentration in air and Hg concentration in precipitation in South Lake than that of Jingyue Pool indicat-ed that mercury deposition was influenced by anthropogenic sources(especially from coas combustion).Hg concentration in precipitation is related with particulate Hg in the atmosphere.Dry deposition fluxes were estimated by using dry deposi-tion model on the base of particulate Hg concentrations in the atmosphere,they were estimated by using dry deposi-tion model on the base of particulate Hg concentrations in the atmosphere,they were 35.5μg/(m^2.a) for South lake and 15.3μg/(m^2.a)for Jingyue Pool.Combined with precipitation amount,wet deposition fluxes were estimated in these two sites,152.2μg(m^2.a)for South Lake and 61.2μg/(m^2.a)for Jingyue Pool.Atmospheric Hg deposition fluxes were 160.2g/a for South Lake and 328.62g/a for Jingyue Pool.e 相似文献
20.
I.INTRODUCTIONIntherecentyears,theresearchershavepaidattentiontotheproblemsofcarbonbalanceandcarboncycleintheearthecosystem,withtheincreaseofCQZamountintheearthatmosphere.Mireisoneoftheecotypesinwhichcarbonaccumulationrateisthefastest,anditisthestrongestsinkforac(Branirgd,1980).Butthereislicitedinformationavailableaboutopconcentrationovermire.SomemeasurementsaboutthetemPOralandspatialgradientofopconcentrationhavebeenmadewithinoraboveasugarbeetcanopy(Brown,1970),corncanopy(Alien,1971;R… 相似文献