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ID:33488231
大小:1.39 MB
页数:51页
时间:2019-02-26
《东海区小黄鱼资源评估与其管理策略的研究》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、◆●上海海洋人学硕士学位论文渔业的可持续利用。关键词:东海区,小黄鱼,渔业资源评估,渔业资源管理III●上海海洋人学硕士学位论文StudyonthefishstockassessmentandmanagementstrategyofLarimichthyspolyactisintheEastChinaSeaAbstractSmallyellowcroaker,asoneofourcountry’Seconomyfisheryspecies,alwaysoccupiesaveryimportantpositioninourcountry’Sfisheryindustry.Itsre
2、sourceshaveundergonethreephasesincludingprosperity,declineandrecovery.Duringrecentyears,althoughtheresourcesofsmallyellowcroakergetsomerelativerecovery,thephenomenoncontainingitsindividualminiaturization,advancedfirstmaturity,juvenilefishcompositionamongcatchesbecomeincreasinglyprominent.Ther
3、esourcestructureisratherfragile.Inordertohaveabetterunderstandingofthecurrentsituationofsmallyellowcroaker’resources,andtoreasonablyuseandmanagesmallyellowcroaker,sfisheryresourcesundertheavailablefisheryresources,thedatausedforthisstudyareobtainedfromthefourquarters’demersaltrawlinginvestiga
4、teddocuments,FisheryStatisticsYearbookandseaconditions(temperature,runoffandwindspeedetc.)from1999to2008inEastChinaIV●上海海洋人学硕士学位论文Sea.Thepapersystematicallyanalyzessmallyellowcroaker’Sresourcesfromdifferentangels,usingmathematicalstatisticsandstockassessmentmodel,inordertoprovidereferablevalu
5、eforthecontinuousdevelopmentofsmallyellowcroaker’SresourcesintheEastChinaSea.Firstly,thispaperstudiesonthesmallyellowcroaker’SresourcevolumeinEastChinaSeafrom1999to2008.Accordingtotheresultoftheverificationandresearch,theusageoftheEastChinaSea’Ssmallyellowcroakerisonahighdevelopedlevel.Theave
6、rageannualresourcevolumefrom1999to2008doesn’tchangegreatly,buttheresourceofearlyfishingseasonvariesinacertainlevelwhichisrelatedtochangeofeachyear’sfishingmortalitycoefficient.Basedonthecomparisonbetweeneachyear’scatchesandMSY,theannualcatchesallexceedMSY.Butfromtheincreasingtrendofsmallyello
7、wcroakers’productivequantityinrecentyears,itisfoundthattheresourcesofsmallyellowcroakerdon’tdecline.Thispaperthinksthatsincethefirstcaptureafterthesummercloseseason,thejuvenilefishisservedasmaincatcheswhichresultsinthecatcheskeepahighincreasi
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