The Influence of Environment Changes on Catch Rate of Yellowfin Tuna(Thunnus albacarest ) and Bigeye Tuna (Thunnus obesus) of Longline Fishery in South China Sea. / 海洋環境變動對南中國海產黃鰭鮪與大目鮪之延繩釣釣獲率影響

碩士 / 國立高雄海洋科技大學 / 漁業生產與管理研究所 / 95 / In order to understand how the marine environment changes in South China Sea affects the catch rate of yellowfin tuna and bigeye tuna for longline fishery, the data of SST (Sea Surface Temperature) and Chlorophyll a between 1990 and 2004 were collected in this study as the index of marine environment changes, along with the catch data of 5 degree square space provided by SPC (Secretariat of the Pacific Community) and carried out the correlation coefficient test. The results suggest that the CPUE of yellowfin tuna decreases with increasing of SST between 1990 and 2004, which shows significant negative correlation (r=-0.53, p<0.05). Meanwhile, the increasing CPUE of bigeye tuna increases with increasing of SST, which shows obviously positive relation (r=0.76, p<0.05).
The Chlorophyll a and SST in South China Sea between 1990 and 2004 show an significant negative correlation (r=-0.53, p<0.01), in other words, the higher sea surface temperature involving with the lower Chlorophyll a. There was an significant positive correlation(r=0.52, p<0.05)between the changes of Chlorophyll a and CPUE of yellowfin tuna during the period of abnormal high temperature in South China Sea (1997.09-1999.04, 2000.12-2001.06, 2002.11-2003.04). But Anomalies of Chlorophyll a and CPUE of yellowfin tuna during the whole period (1997.09-2004.12) did not present an significant positive correlation (r=0.18, p>0.05), according to correlation coefficient test. Therefore the results indicate that the increase of SST would cause the reduction of Chlorophyll a and indirectly conduct the decrease of CPUE of yellowfin tuna. However no matter what period is, the whole period or abnormal higher temperature period, the bigeye tuna seemed to be not affected by the change of Chlorophyll a.

Identiferoai:union.ndltd.org:TW/095NKIM8451010
Date January 2007
CreatorsYin, Yih-Huei, 殷毅輝
ContributorsLiao, Yih-Yia, Cheng, Lei-Zong, 廖翊雅, 鄭利榮
Source SetsNational Digital Library of Theses and Dissertations in Taiwan
Languagezh-TW
Detected LanguageEnglish
Type學位論文 ; thesis
Format76

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