XVI International Botanical Congess

To understand how flooding affects wood and bark anatomical characters we selected five species growing in a mangrove community, where flooding period varies from 4, 8, or more than 9 months during the year. We sampled three individuals/species/zone in two sites for each flooding period. Measurements of 15 anatomical characters were made. Discriminant analysis showed that three wood and two bark features contributed to significant differences among zones. Regression analysis showed that proportion of solitary vessels and proportion of vessels in radial multiples were related to water pH. Analysis of variance showed that relative conductivity is explained by salinity, whereas vulnerability by flooding level and soil texture. Vessel features show a similar trend in three of the five species studied, when growing under the longest flooding period. Notably Avicennia germinans quantitative characters do not show any response to flooding period. Aerenchyma is associated to flooding, however, different patterns of aerenchyma distribution occurred in the species studied.