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Six wide-ranging mangrove species, Rhizophora apiculata, R. mucronata, Avicennia marina, A. officinalis, Bruguiera gymnorrhiza, and B. sexangula, were selected to study the growth and survival of seedlings under three contrasting salinity treatments over a 30-week period: low (3-5psu), moderate (15-17psu) and high (33-36psu). Seedlings grown under high salinity exhibited significantly lower performance (p<0.05) in survival rates, cumulative shoot height, mean growth rates, mean total leaf area, and mean dry weight, compared to those under low and moderate salinity regimes. The low salinity treatment provided the best conditions for initial establishment and growth of the seedlings of all species until 15-20 weeks of age. However, the same seedlings showed better performance under moderate salinity after 15-20 weeks of age (shift in optimal salinity), implying that adaptation to salt and physiological needs of mangrove seedlings varies with age. These results have practical implications of use in raising up mangrove nurse species for planting since it indicates that seedlings should get low salinity water until four to five months of age and then moderately saline water, in order to achieve maximum growth and survival., SCOPUS: ar.j, info:eu-repo/semantics/published

Studies of predation on propagules of the mangroves Avicennia marina, Bruguiera exaristata, Ceriops tagal and Rhizophora stylosa were made in a forest in northern Australia to test the generality of the dominance-predation model. This model states that an inverse relationship exists between the dominance of a species in the canopy of mangrove forests and the rate of predation on the propagules of that species Significant differences in predation were found among the four species, and among patches of forest dominated by the different species. Predators attacked more than 50% of the propagules of all species except R stylosa, so are likely to significantly affect forest structure. The intensity of predation did not, however, vary as the dominance-predation model predicted. Instead, predation on the propagules of a species appeared to depend on the availability of propagules of other, more highly preferred, species.