Leaf and flower formation in shoot tips of mangrove trees in Pernambuco, Brazil
2013
Medeiros, Thereza C. C. | Sampaio, Everardo V. S. B.
Leaves are major components of mangrove productivity, but data on leaf dynamics are scarce. We marked the shoot tips of three species in four sites of a riverine mangrove and monitored leaf formation, senescence and abscission and flower formation. The leaf area and biomass in the mangrove were estimated using phytosociological data. Leaf size and formation were similar among the four sites. The tips of Rhizophora mangle had more leaf scars (41), more leaves present (9.7), a faster leaf formation rate (one every 26 days) and a shorter life span (8.4 months) than those of Avicennia schaueriana (10, 8.1, 48 days and 13.1 months, respectively) and Laguncularia racemosa, except for the shorter life span (15, 6.6, 31 days and 6.8 months, respectively). The proportion of tips that flowered was higher in L. racemosa (13 %) and in R. mangle (11 %) than in A. schaueriana (2 %). The largest biomass of the average R. mangle leaf (0.75 vs. 0.53 and 0.37 g leaf⁻¹, of L. racemosa and A. schaueriana, respectively) and the highest plant density of this species (2,590 vs. 694 and 202 plant ha⁻¹, respectively) resulted in it having the greatest leaf productivity (10.6 Mg ha⁻¹ year⁻¹ compared to 2.4 Mg ha⁻¹ year⁻¹ for L. racemosa and 0.3 Mg ha⁻¹ year⁻¹ for A. schaueriana). The total leaf production is higher in this mangrove than most of those reported for other mangroves in the world.
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