| Abstrakt: |
As a tropical country, Indonesia is gifted with a whole year sun exposure along with two seasons, making mangrove plants possible to keep growing. However, the climatic difference between seasons may have implication to plants' ecophysiological activity. This research aimed to study the dynamic of tannin content in Rhizophora apiculate and Avicennia marina, to analyze the impact of seasonal dynamic to the tannin content. The research was carried out through observation. Observation was performed twice, once at the rainy season and once at the dry season. Six samples were taken from the field. Tannin samples were taken from mangrove bark, preserved in a cold storage, and then analyzed in the laboratory. Tannin content analysis was performed in LPPT UGM. Data analysis was performed with independent sample t-test for mean difference. The result showed that during the rainy season the tannin content in R. apiculata was much lower than in the dry season. During the rainy season, the tannin content of R. apiculata was between 17.87 – 19.16 % (18.50 ± 0.59 %), while in the dry season the range was between 22.55 – 46.59 % (40.15 ± 8.88). T-test analysis showed a significant difference between seasons with t-value of -5.960 and p = 0.000. During the rainy season, the tannin content of A. marina was between 4.14 – 6.58 % (5.29 ± 0.80 %), while in the dry season the range was between 2.88 – 4.91 % (3.75 ± 0.88%). T-test analysis showed a significant difference between seasons with t-value of -2.886 and p = 0.034. The result suggested that seasonal difference contributes significantly in the dynamic of tannin content in R. apiculata and A. marina [ABSTRACT FROM AUTHOR] |
