简介:乡村振兴战略是一项复杂的系统性工程,“三渔”作为农业农村农民工作的重要板块,应根据乡村振兴总部署明晰发展战略。渔业文化资源作为重要的“三渔”资源类型,对其价值的科学评价,是进行有效保护和高效开发的重要前提条件。基于层次分析法的分析框架,通过邀请专家学者填写打分表的方式构建渔业文化资源价值评价指标体系,以此构建模型并进行综合分析。研究结果表明,在渔业文化资源价值评价体系中,文化价值所占权重最高,社会价值和生态价值次之,体验价值和经济价值影响最小。在乡村振兴的背景下,广大渔村应该在宏观层面重视渔业文化资源在经济发展中的作用,在中观层面打造渔业文化品牌,在微观层面发挥民间的力量。
简介:介绍ITRF2014的定义、测站分布、输入数据、分析策略以及与ITRF2008的转换参数,并分析ITRF2014相对于ITRF2008的改进.ITRF2014是国际地球参考框架ITRF的最近一次更新,它是基于四种空间大地测量技术(VLBI、SLR、GNSS和D0RIS)重新处理解实现的.相较于ITRF2008,ITRF2014不仅在观测数据和测站数量上有所增加,还改善了对非线性运动的处理,包括对周期性信号的估计以及对震后形变(post-seismicdefomiation,PSD)的改正,并提供了PSD模型和地球质心运动模型两个新产品.ITRF2014为地球科学等相关领域的研究与应用提供了统一的空间基准,也为其他坐标框架的维持与精化提供了参考.
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简介:ThesynopticsituationandmesoscalestructureofanexplosiveextratropicalcycloneovertheNorthwesternPacificinMarch2007areinvestigatedthroughweatherstationobservationsanddatareanalysis.Thecycloneislocatedbeneaththepolewardsideoftheexitofa200hPajet,whichisastrongdivergentregionaloft.Atmid-level,thecycloneliesonthedownstreamsideofawell-developedtrough,whereastrongascendingmotionfrequentlyoccurs.Cross-sectionanalyseswithweatherstationdatashowthatthecyclonehasawarmandmoistcore.A'nose'ofthecoldfront,whichischaracterizedbyalow-levelprotrudingstructureintheequivalentpotentialtemperaturefield,formswhenthecyclonemovesoffshore.This'nose'structureishypothesizedtohavebeencausedbytheheatingeffectoftheKuroshioCurrent.Twolow-leveljetstreamsarealsoidentifiedonthewesternandeasternsidesofthecoldfront.Thewesternjetconveyscoldanddryairat800-900hPa.Thewindinthenorthernpartisnortheasterly,andthewindinthesouthernpartisnorthwesterly.Bycontrast,theeasternjetcarrieswarmandmoistairintothecyclonesystem,ascendingnorthwardfrom900hPato600-700hPa.Thesouthernpartisdominatedbythesoutherlywind,andthewindinthenorthernpartissouthwesterly.Theeasternandwesternjetssignificantlyincreasetheairtemperatureandmoisturecontrastinthevicinityofthecoldfront.Thisincreasecouldplayanimportantroleinimprovingtherapidcyclogenesisprocess.
简介:InordertoexaminetheseasonalandspatialdistributionsofbenthicanimalsintheintertidalmudflatofthesouthernYellowRiverDelta,fieldinvestigationswerecarriedoutin2007and2008andmultiplemethodswereapplied.Resultsshowedthat,thebiomassofmacrobenthosrangedat0.75-1151.00gwetm-2andaveragedat156.31gwetm-2,inwhichMactraveneriformisaccountedfor75.6%-93.4%ofthetotalmacrobenthicbiomass.Morethan90%ofmacrobenthosinhabitedinthemiddleandlowtidelines,andhigherbiomassoccurredinearlysummerandlowerinwinter.Statisticalanalysisshowedthat:1)M.veneriformisgrowthwasprimarilyfavoredathighertemperatureandlowersalinity;2)afterlongtimeinteraction,benthicbivalvegrazersledtopatchingdistributionsofChlorophylla(Chla);3)macrobenthicbiomasspositivelyrelatedwithChlawhentheconcentrationofChlawaslow,buttheywerenegativelyrelatedwhenChlaconcentrationwashigh;and4)furthermore,thebiomassofbenthicbivalvespeakedinthesedimentwithmediangrainsizeabout0.55mm,butdecreasedgraduallyincoarseorfinesediments.Thesecondaryproductivityrangedat0.37?283.68gm-2yr-1andaveragedat47.88gm-2yr-1,inwhich69.7%wascontributedbyM.veneriformisItwasestimatedthatprimaryproductionwastransformedtosecondaryproductionatarateof6.87%approximately,whichimpliesthatthereisalocalsustainabilityofhighbivalveproduction.