Annual change in photosynthetic pigment contents of Zostera marina L. in Swan Lake
This study investigated the annual change in photosynthetic pigment contents of Zostera marina L. in Swan Lake from April 2009 to March 2010. Photosynthetic pigment of Z. marina L. was extracted using the soaking method and measured spectrophotometrically. The maximum value of total chlorophyll content observed was 2.40 ± 0.034 mg/g in October, while the minimum was 1.22 ± 0.028 mg/g in June. On the other hand, maximum chlorophyll a content was 1.58 ± 0.020 mg/g in October and the minimum was 0.76 ± 0.036 mg/g in March. The highest and lowest chlorophyll b content was 0.83 ± 0.016 mg/g in October and 0.40 ± 0.005 mg/g in January, respectively. Finally, carotenoid was highest at 0.39 ± 0.006 mg/g in January and least at 0.13 ± 0.004 mg/g in April. Based on seasonal analysis, chlorophyll content was higher during the late-autumn and early-winter, and lower in the summer; while carotenoid content was higher during the late-autumn and winter, and lower in early-spring and late-summer.
Key words Zostera marina L., Swan Lake, photosynthetic pigment, annual change.