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根据2012年1—8月和2014年12月—2015年7月中国大型拖网渔船在中东大西洋中部海域佛得角海岸(FAO34渔区3.11小区)的渔捞日志资料以及遥感获取的海洋环境数据,利用产量重心法、地统计插值、数理统计、广义加性模型(generalized additive models,GAM)等方法 ,对该海域中上层鱼类平均单位捕捞努力渔获量(CPUE)的月变化、中心渔场的时空变动及其与海表温度(SST)、叶绿素a浓度、经度、纬度的关系进行了分析。结果表明:该海域各月平均CPUE基本呈先减少、后增加的趋势;中心渔场的分布具有明显的月变化,基本呈先由北往南推移,且在3—4月份到达最南端,后由南往北推移趋势;不同月份渔场中心叶绿素a浓度为0~10 mg·m-3,且渔场中心叶绿素a浓度以7~9 mg·m~(-3)居多;不同月份渔场中心的SST为17.3~27.6℃,且渔场中心的SST以19~21℃居多。GAM模型分析表明,渔场的最适SST为20~22℃,最适叶绿素a浓度为4.480~7.388 mg·m~(-3),经度集中在16°40’W附近,纬度集中在19°N附近。海洋环境与CPUE的回归方程显著性检验表明,除了SST呈不显著外,叶绿素a浓度和空间因子与CPUE的回归关系均极显著(P<0.01),影响渔场的因子按重要性从大到小依次为经度、纬度、叶绿素a浓度和SST。分析认为,洋流产生并导致的涌升流的位置变化对佛得角海岸FAO34渔区3.11小区中心渔场的时空变化具有重要影响。
According to the fishing logs of large trawlers in China from Cape Verde Coast (FAO34 fishing area 3.11 plots) and the marine environment data acquired by remote sensing in January-August 2012 and July 2014-July 2015, Based on the methods of yield center of gravity method, geo-statistic interpolation, mathematical statistics and GAM, the monthly variation of average catches per catch (CPUE) of upper-middle-class fish in this area was calculated. Spatiotemporal variation and its relationship with sea surface temperature (SST), chlorophyll a concentration, longitude and latitude were analyzed. The results showed that: the average monthly CPUE of the sea area decreased first and then increased; the distribution of the central fishery had obvious monthly changes, basically shifting from north to south first and reached the southernmost point from March to April, The trend of chlorophyll a in the fishery center was 0 ~ 10 mg · m-3 and the concentration of chlorophyll a in the fishery center was 7 ~ 9 mg · m ~ (-3) in most months. The SST 17.3 ~ 27.6 ℃, and the fishery center SST to 19 ~ 21 ℃ majority. The GAM model analysis showed that the optimum SST of the fishery was 20-22 ℃, the optimum concentration of chlorophyll a was 4.480-7.388 mg · m -3, the longitude was around 16 ° 40’W, and the latitude was about 19 ° N nearby. Significant test of the regression equation between marine environment and CPUE showed that except the SST was not significant, the regression relationship between chlorophyll a concentration and space factor and CPUE was extremely significant (P <0.01) Followed by longitude, latitude, chlorophyll a concentration and SST. It is considered that the change of the position of the upwelling flow caused and produced by the ocean current has an important influence on the spatio-temporal change of the fishery of 3.11 Community Center in FAO34 fishing area on the Cape Verde coast.