捕捞压力和气候因素对黄渤海带鱼渔获量变化的影响

渔获量的变化不仅受捕捞作用的影响,还与气候变动有关。本研究采用1956 2006年黄渤海带鱼渔获量数据,分析带鱼渔获量变动对捕捞压力和气候因素的响应。带鱼渔获量可分解成变化趋势和年间变动。变化趋势主要由捕捞压力的增加而引起,Fox模型的拟合结果表明,带鱼渔获量与捕捞努力量的回归关系显著(P<0.01)。移除渔获量的年际变化趋势后,渔获量变动与黄海冬季季风、东海夏季季风、黄河流域和黄渤海沿岸降水呈显著的正偏相关(P<0.02),与黄海海表温度、黄海夏季季风、渤海夏季及冬季季风呈显著的负偏相关(P<0.05)。这种相关关系表明,气候因素影响到黄渤海带鱼渔获量的年间变动。陆地降水和径流给黄渤海海域输入了丰富的营养盐;而季风则控制着营养盐的流动及分布,从而影响海域的初级生产力;水温的变化会直接影响鱼类的生长、摄食、产卵及洄游等,影响鱼类种群的变化。黄渤海带鱼渔获量可以用捕捞努力量和气候因素加以拟合(P<0.01),说明气候因素对黄渤海带鱼渔获量有显著的影响。另外,作者认为在全球增暖的背景下,未来黄渤海带鱼渔获量可能会减少,且渔获量的年间波动幅度可能增大。

Analysis on responses of hairtail catches to fishing and climate factors in the Yellow Sea and Bohai Sea, China

Changesinfishharvestarenotonlyimpactedbyfishing,butalsoinfluencedbyclimatevariability.Basedondataofhairtailcatchesbetween1956and2006intheYellowSeaandBohaiSea,China,theresponsesofcatchestofishingandclimatefactorswereanalyzed.Thecatchtimeseriescanbecompartmentalizedintoaninter-annualtrendandvariations.Theinter-annualtrendwasfishingefforts.Thiswassuggestedbyhighlysignificantregressionofhairtailcatchestofishingeffort.Afterthecatchtrendwasremoved,therewere<0.02)oftheresidualvariationsincatchestowinterwindspeedintheYellowSea,summerwindspeedintheEastChinaSea,andannualprecipitationinYellowRiverValleyandthecoastalregionoftheYellowSeaandBohaiSea,whereastheseasurfacetemperatureandsummerwindspeedintheYellowSea,aswellassummerandwinterwindspeedsintheBohaiSea.Thelinkagesuggeststhattheclimatefactorsgovernthehairtailcatchvariations.ItwasinferredthatrunoffinputnutrientstotheYellowSeaandBohaiSea,whilemonsoonscontrolledthetransportanddistributionofthenutrients,andtheseprocessescanhaveimpactsontheprimaryproductivity.Changesinwatertemperaturecouldalsodirectlyaffectthegrowth,feeding,spawning,andmigrationofthefish,andthus,influencethefishpopulationsize.Thehairtailcatchtimeseriescanbejointlyfittedbyfishingeffortandclimaticfactors(,climatefactorscansignificantlyinfluencethehairtailcatches.Inthecontextofglobalwarming,itwasprojectedthatthefutureclimatechangeswouldleadtoreductioninhairtailproductionintheYellowSeaandBohaiSea,andthehairtailcatchvariationswouldbecomeevengreater.