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Variations in the distributions of Centropages chierchiae and Temora stylifera (Copepoda: Calanoida) in the north-eastern Atlantic Ocean and western European shelf waters. Reporter : Li Chi-Tien. 東北大西洋和西歐沿海 Centropages chierchiae 與 Temora stylifera 分布之變動.
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Variations in the distributions of Centropages chierchiae and Temora stylifera (Copepoda: Calanoida) in the north-eastern Atlantic Ocean and western European shelf waters Reporter:Li Chi-Tien 東北大西洋和西歐沿海 Centropages chierchiae與 Temora stylifera分布之變動 J. A. Lindley and S. Daykin ICES Journal of Marine Science, 62: 869e877 (2005)
Introduction Celtic Sea English Channel Bay of Biscay Iberian coastal waters (NAO)
Introduction C. chierchiae It restricted to the eastern Atlantic, Mediterranean, and western Indian Ocean Celtic Sea English Channel T. stylifera Bay of Biscay It is known from all the oceans as well as the Mediterranean Sea and Red Sea Iberian coastal waters Found in the tropical and subtropical waters The objective of this study was to provide detailed information on the occurrence of these species in the CPR survey and to analyse the changes in relation to some environmental variables.
Methods Plankton sampling CPR survey Celtic Sea English Channel Bay of Biscay Iberian coastal waters C. chierchiae T. stylifera
Methods Environmental data Statistical analyses • Sea surface temperature (SST) • in situ sea surface observations and satellite derived estimates • The shelf edge current (SEC) • described further in Holliday and Reid (2001) and Reid et al. (2001) • The North Atlantic Oscillation (NAO) • The Gulf Stream North Wall Index (GSNWI) • North hemisphere temperature (NHT) • Lamb weather types Pearson’s correlation. (NHT) (NAO) (GSNWI)
Results Distributions Celtic Sea English Channel Bay of Biscay Iberian coastal waters
Results Seasonal cycles
Results Year-to-year changes
Results 1959 1989
Results NHT:The lower values in the mid-1960s, and steady rise since 1977 NAO:The high value in 1989 GSI:Low values in the 1970s, and increase until 1995 SEC:A peak in 1989, and a decline to 2000, with exceptionally in 1998 and 1999 NW:The number of days of northwesterly weather over Britain, higher in 1979
Discussion (NHT)
Discussion ballast water 1959 1989
Discussion The seasonal cycles of C. chierchiae in Bay of Biscay and Iberian coastal waters are similar to the frequent occurrence through late spring and summer. The seasonal cycle of T. stylifera with its seasonal peak late in the year is consistent with the results from the southern coastal area of the Bay of Biscay
Conclusion The results of the analyses of differences between the species in the correlations with the NHT, SEC and NAO, indicate that ecological differences between species will result in different responses to climate change. Our results, therefore, support Villate et al. (1997) in suggesting that Temora stylifera can be a key species in monitoring climate changes in the Bay of Biscay (and now more northerly areas) but adding Centropages chierchiae would help to avoid dependence on the ecological characteristics of a single species.