Abstract:

During three successive austral summers from Dec. to March of 1992/1993,1993/1994 and 1994/1995,investigation was carried out on phytoplanktonic chlorophyll a content in Great Wall Bay,Antarctica.The results showed that among the three summers the concentration of chlorophyll a in the summer of 1992/1993 was the highest with an average value of 3.79 mg/m 3 ,the range of chlorophyll a variation in this year was the largest,too. The year to year variation of average value of chlorophyll a was 3.79 mg/m 3 (1992/1993)>1.80 mg/m 3 (1993/1994)>1.20 mg/m 3 (1994/1995).The variation range of chlorophyll a was 10.10 mg/m 3 (1992/1993)> 6.57 mg/m 3 (1993/1994)> 2.41 mg/m 3 (1994/1995). Compared with chlorophyll a concent in austral summer in other area of Antarctica,the chlorophyll a in Great Wall Bay in the three year was relatively high though it was lower than that of 11.60 mg/m 3 in Jan. 1959 in Gerlache Strait and 56.10 mg/m 3 in Dec. 1961 in McMurdo Sound. The vertical distribution of chlorophyll a in water column was also presented.