摘要
Accuratedeterminationofflushingtimeiscrucialformaintainingsustainableproductioninfishculturezones(FCZs),asitrepresentsthephysicalself-purificationcapabilityviatidalexchangewithcleanwaterintheoutersea.However,owingtothetemporalandspatialcomplexityofthecoastalflushingprocess,existingmethodsfordeterminingflushingtimemaynotbegenerallyapplicable.Inthispaper,asystematicmethodfordeterminingtheflushingtimeinFCZsispresented,inwhichbathymetry,runoff,tidalrangeandstratificationareproperlyaccountedfor.Wedeterminetheflushingtimevianumericaltracerexperiments,usingrobust3Dhydrodynamicandmasstransportmodels.ForFCZslocatedinshelteredandland-lockedtidalinlets,thesystemboundarycanbenaturallydefinedattheconnectionwiththeopensea.ForFCZslocatedinopenwaters,hydrodynamictrackingisfirstusedtoassesstheextentoftidalexcursionandthusdelimittheinitialboundarybetweencleanwaterandpollutedwater.ThisgeneralmethodisappliedtoalldesignatedmarineFCZsinHongKongforboththedryandwetseasons,including20shelteredFCZs(insemi-enclosedwatersofToloHarbour,MirsBay,andPortShelter)and6FCZsinopenwaters.OurresultsshowthatflushingtimeisthelongestininnerPortShelter(about40daysindryseason),andtheshortestfortheFCZsinopenwaters(lessthanoneweekindryseason).Inaddition,theflushingtimeindryseasoniscommonlylongerthanthatinwetseason:20%~40%formostwell-shelteredFCZs;2.6~4timesfortheothers.Ourresultsindicateapositivecorrelationbetweentheflushingtimeanddistancetoopenboundary,supportingtheviewthattheflushingtimeofaFCZiscloselyrelatedtoitslocation.ThisstudyprovidesasolidbasisformariculturemanagementsuchasthedeterminationofcarryingcapacityofFCZs.
出版日期
2011年04月14日(中国Betway体育网页登陆平台首次上网日期,不代表论文的发表时间)