CAJ | 학술논문

为了解热带印度洋大眼金枪鱼(Thunnus obesus)适宜的垂直和水平空间分布范围,采用Argo浮标剖面温度数据重构热带印度洋10℃、12℃、13℃和16℃月平均等温线场,网格化计算了12℃、13℃等温线深度值和温跃层下界深度差,并结合印度洋金枪鱼委员会(IOTC)大眼金枪鱼延绳钓渔业数据,绘制了12℃、13℃等温线深度与月平均单位捕捞努力渔获量(CPUE)的空间叠加图,用于分析热带印度洋大眼金枪鱼中心渔场 CPUE 时空分布和高渔获率水温的等温线时空分布的关系.结果表明,从垂直分布来看,热带印度洋中心渔场延绳钓高渔获率区域垂直分布在温跃层下界以下,在表层以下150~400 m 深度区间.从水平分布来看,12℃等温线,高 CPUE 区域大多深度值<350 m,众数为225~350 m;深度值超过500 m的区域CPUE普遍较低.13℃等温线,高值CPUE出现的地方大多深度值<300 m,众数为190~275 m;深度值超过400 m的区域CPUE普遍较低.全年在15oS以北区域,高渔获率的垂直分布深度更加集中.采用频次分析和经验累积分布函数,计算其最适次表层环境因子分布,12℃等温线250~340 m;13℃等温线190~270 m;12℃深度差30~130 m;13℃深度差0~70 m.研究初步得出热带印度洋大眼金枪鱼中心渔场适宜的水平、垂直深度值分布区间,可以辅助寻找中心渔场位置,同时指导投钩深度,为热带印度洋金枪鱼实际生产作业和资源管理提供理论支持.
위료해열대인도양대안금창어(Thunnus obesus)괄의적수직화수평공간분포범위,채용Argo부표부면온도수거중구열대인도양10℃、12℃、13℃화16℃월평균등온선장,망격화계산료12℃、13℃등온선심도치화온약층하계심도차,병결합인도양금창어위원회(IOTC)대안금창어연승조어업수거,회제료12℃、13℃등온선심도여월평균단위포로노력어획량(CPUE)적공간첩가도,용우분석열대인도양대안금창어중심어장 CPUE 시공분포화고어획솔수온적등온선시공분포적관계.결과표명,종수직분포래간,열대인도양중심어장연승조고어획솔구역수직분포재온약층하계이하,재표층이하150~400 m 심도구간.종수평분포래간,12℃등온선,고 CPUE 구역대다심도치<350 m,음수위225~350 m;심도치초과500 m적구역CPUE보편교저.13℃등온선,고치CPUE출현적지방대다심도치<300 m,음수위190~275 m;심도치초과400 m적구역CPUE보편교저.전년재15oS이북구역,고어획솔적수직분포심도경가집중.채용빈차분석화경험루적분포함수,계산기최괄차표층배경인자분포,12℃등온선250~340 m;13℃등온선190~270 m;12℃심도차30~130 m;13℃심도차0~70 m.연구초보득출열대인도양대안금창어중심어장괄의적수평、수직심도치분포구간,가이보조심조중심어장위치,동시지도투구심도,위열대인도양금창어실제생산작업화자원관리제공이론지지.
We evaluated the isothermal distribution of subsurface temperatures in the bigeye tuna (Thunnus obesus) fishing grounds in the tropical Indian Ocean. We plotted the isothermal depths at 10, 12, 13, and 16°C on a spatial overlay map using data collected on monthly basis from Argo buoys and monthly CPUE (catch per unit effort) from bigeye tuna long-lines. In addition, the differences in depth between the 12 and 13°C isolines at the lower boundary of the thermocline were computed to determine the relationship between bigeye tuna vertical distribution and thermocline depth. Our analysis suggested that the vertical range of optimal temperatures (10 and 16°C) in the area of high CPUE was between 150 and 400 m, and was beneath the lower boundary depth of the thermocline. The overlay maps suggest that CPUE is highest in areas where the 12°C isothermal depth is shallower than 350 m (mode:225?350 m). Conversely, if the depth is>300 m, the CPUE tends to be low. Similarly, the highest CPUEs were observed in areas where the 13°C isothermal depth was shallower than 300 m (mode:190?275 m), whereas CPUE was low when the depth exceeded 400 m. The vertical distribution of high hook rates was concentrated in the area to the north of 15°S. We used a frequency analysis and the empirical cumulative distribution function to compute the optimum range of subsurface factors. The optimum ranges for the12 and 13°C isothermal depths were between 250?340 m and 190?270 m, respectively. The optimum depth difference ranges were 30–130 m for the 12°C isothermal depth and 0–70 m for the13°C isothermal depth. We documented the distribution interval and vertical depth range for the central fishing ground of bigeye tuna. Our results provide a reference for improving the efficiency of thelong-line fleet and aiding in resource management.