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Erftemeijer, P.L., Hamerlynck, O., 2005. Die-back of the mangrove Heritiera littoralis Dryand, in the Rufiji Delta (Tanzania) following El Niño floods. Journal of Coastal Research 228-235.
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East Africa: Tanzania
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During the 1997-1998 El Niño events, heavy rains caused the Rufiji River to swell well beyond its banks resulting in extensive floods, which lasted for at least 6 months. The flow of the Rufiji River during this period had reached an exceptionally high peak maximum, and after the floodwaters had receded, it became apparent that significant tracts of mangrove forest in the upper reaches of the northern delta had died. Analysis of a series of 1999 aerial photographs indicated that an area of approximately 117 ha of mangrove forest had experienced massive tree mortality. A detailed field survey three years after the flood revealed that this mortality was for the major part limited to mature trees of the economically valuable mangrove species Heritiera littoralis. Another tree species, Barringtonia racemosa, co-occurring in the same forest stands, had largely survived the excessive floods. Forest regeneration of the affected areas was characterized by a massive development of B. racemosa seedlings and saplings (>9,000 and >4,000 ha1 respectively). Regrowth of H. littoralis was minimal (20 seedlings ha-1 and 22 saplings ha-1) and viable Heritiera seeds on the forest floor were absent (unlike Barringtonia seeds, which reached densities of over 4,000 ha-1).
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