Plant Community Structure, Fire Disturbance, and Recovery in ...

Contributions to the Study of Biological Diversity Vol. 3
Plant Community Structure, Fire Disturbance, and Recovery in
Mangrove Swamps of the Waini Peninsula, Guyana
The Waini Peninsula is the site of the
majority of Guyana’s remaining mangrove
swamps. In the ongoing development of
Guyana’s protected areas system (EPA Guyana
2002), there has been a focus on the “Shell
Beach” portion of the Waini Peninsula as a
candidate site, primarily because of its extensive
mangrove swamps and marine turtle nesting
beaches (Humm 2001). The area is important
beyond its uniqueness within Guyana, as the
high-sediment coastline of the Guianas differs
significantly from Caribbean mangrove settings
that are most often studied in the Neotropics.
There was a basic need for description of the
plant communities in the prospective protected
area, to provide baseline floristic and ecological
information upon which future scientific
research and monitoring can build. In the
broader perspective, it is important within
mangrove ecology to expand documentation of
the variety of biotic elements, structures, and
disturbances that occur in mangrove ecosystems,
to provide for suitable understanding,
protection, and management (Ellison 2002; Finn
et al. 1998; Jiménez et al. 1985). The disturbance
of the study site just prior to field work offered
opportunities to address basic questions about
the nature of mangrove dispersal and recovery.
As a basis for study, plant specimens were
collected and identified, and a vouchered species
list was assembled for the Waini Peninsula.
Some of those collections expanded documented
species ranges. The plant collection results were
compared to other available botanical data for
the region, at various scales, to place the Waini
by
Thomas H. Hollowell 1
INTRODUCTION
flora in environmental and biogeographic
context.
In addition, the plant communities of the
Waini Peninsula were classified, described, and
mapped. As part of that task, the unusual
phenomenon of large-scale fires in the mangrove
swamps was documented, including estimates
of the extent of impacted plant communities.
Documentation of the fires formed a
contribution to knowledge of disturbance types
that have been known to affect mangrove
systems. The fires occurred during the extreme
El Niño event of 1997 to 1998, and so may have
been linked to global climate change processes
(Laurance 1998; Snedaker 1995).
Among the plant species present, the Asian
mangrove species, Nypa fruticans Wurmb., was
of particular interest and so was documented and
reviewed in detail. Nypa Wurmb. is an exotic
species that may spread in important riverine
mangrove swamps of the Waini Peninsula
region, making it a concern both in Guyana and
neighboring countries.
Ecological vegetation plots were
established and resampled to provide new
information on the structure of the Waini
Peninsula’s coastal mangrove forests and on the
initial course of regeneration in the fire-affected
mangrove forests. Those structural data allowed
comparisons with information on other
mangrove systems of the world and will aid
additional population structure and succession
trend studies.
Mangrove zonation patterns have been
attributed to both physical and chemical factors
1 Master of Science, George Mason University, 1992
This volume was originally a portion of a dissertation submitted in partial fulfillment of the requirements of the degree of
Doctor of Philosophy at George Mason University. Director: Donald P. Kelso, Associate Professor Environmental Science
and Policy
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