WesampledthesedimentsoftheEastChinaSeaduring2005and2006,andanalysedthecontentsofthebiogenicmatters:biogenicsilica,organiccarbon,andorganicnitrogen.Fromthesurfacedistributionwefoundthecontentsofthesesubstancestobeintherangesof0.72%-1.64%,0.043%-0.82%,and0.006%-0.11%,respectively.Theirdistributionsweresimilartoeachother,beinghighinsidetheHangzhouBayandlowoutsidethebay.Theverticalvariationsofthecontentswerealsosimilar.Inordertodiscusstherelationbetweenthemweanalysedthevariationsofcontentwithdepth.Theyincreasedinthefirst7cmandthendecreasedwithdepth.Thepeakswerefoundatdepthsbetween20to25cm.Thedistributionofcarbonateshowedanoppositetrendtothatofbiogenicmatters.Thecontentoftotalcarbonwasrelativelystablewithrespecttodepth,andtheratioofhighorganiccarbontocarbonateshowedalowburialefficiencyofcarbonate,whichmeansthatthemainburialofcarbonisorganiccarbon.Inordertodiscussthesourceoforganicmatters,theratiooforganiccarbontoorganicnitrogenwascalculated,whichwas8.01to9.65,indicatingthattheorganicmatterinthesedimentswasderivedmainlyfromphytoplanktonintheseawater.
