Checklist of the Plants of the Guiana Shield - Department of Botany ...

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Most parts of Brazil north of the Amazon River
and much of eastern Colombia are poorly explored,
and they are not included in this publication (see
below).
CONSERVATION
With the exceptions of the few populated
localities such as Puerto Ayacucho, Ciudad
Guayana, Ciudad Bolívar, and the agricultural
coastal areas, the environment of the Guiana Shield
has benefited from limited access and low
population densities, although this same isolation
has hindered biodiversity research. Estimates vary,
but approximately 70% (Funk & Richardson 2003)
of the vegetation is still relatively undisturbed by
human activities. Recently, however, the pace of
disturbance has greatly increased; current threats
to the environment include large-scale logging by
Asian and local companies, large- and small-scale
gold and diamond mining, oil prospecting, bauxite
mining, massive hydroelectric projects, wildlife
trade, and population-related pressures such as
burning, grazing, agriculture, and the expansion
of Amerindian villages. Taken together, these
impacts have begun to take their toll, with vast
areas previously left undisturbed are now
vulnerable to increasing disturbance.
The status of conservation efforts varies by
country. Throughout the Guiana Shield, many
areas that are designated as protected or otherwise
restricted are often only “paper” parks because of
a lack of infrastructure and funds to protect them.
Over the last four decades, Venezuela has
established seven national parks, 29 natural
monuments, and two biosphere reserves covering
about 142,280 km², more than 30% of its share of
the Guiana Shield (Funk and Berry 2005). In
Guyana, the progress of conservation efforts has
been slower, with the only substantial protected
area being Kaieteur National Park, its 627 km²
comprising about 0.3% of the country’s area
(Kelloff 2003), with additional reserves under
consideration. Guyana’s 3,710 km² Iwokrama
Forest (Clarke et al. 2001) is dedicated to
sustainable use. Surinam’s protected areas system
includes one national park and a network of 11
reserves, totaling almost 20,000 km², over 12% of
its total area. This includes the recently created
16,000 km² Central Suriname Nature Reserve, an
UNESCO World Heritage Site that joined and
Checklist of the Plants of the Guiana Shield
expanded three existing reserves (see http://
www.stinasu.com). French Guiana has no
officially designated protected areas, but 18
proposed sites total 6,710 km², about 7.5% of its
area (Lindeman and Mori 1989).
The Guiana Shield encompasses part or all of
five countries (excluding the small part in
Colombia) with five different governments, five
official languages, and many more indigenous
languages. Cooperation is sometimes hampered
by border disputes and illegal cross-border
transportation of gold, wildlife, and more recently,
illegal drugs. The implementation of conservation
practices is further complicated by many issues
concerning the indigenous peoples of the region.
All of these challenges will have to be overcome
on the way to designing and maintaining a viable
reserve system for the Guiana Shield.
DISCUSSION
This checklist includes 257 vascular plant
families containing 2,072 accepted genera. We
have recorded over 14,732 accepted subgeneric
taxa, 1,358 of those including a subspecific or
varietal epithet and 13,367 distinct species.
According to our list 6,791 of those species are
from Amazonas, 6,669 from Bolívar, 1,651 from
Delta Amacuro, 7,112 from Guyana, 4,984 from
Surinam, and 5,406 from French Guiana. Of these
species, 293 (2.2%) are estimated to be introduced
and naturalized. In the three Guianas there are
8,933 species and there are 9,814 species in the
Venezuelan Guayana. With 5,482 species found
in both areas there is 41% overlap between the two
areas. Within the checklist area 3,451 species are
listed only for the Guianas and 4,332 are found
only in the Venezuelan Guayana. See Table 1 for
a summary of the numbers of taxa in each family
and Table 2 for the families with the largest number
of species.
The top 15 families (in number of species)
have a total of 7,094 species, which represents over
half of the species in the Guiana Shield area.
According to our list 154 families have 25 species
or less, and 34 families have 26-50 species.
Consequently, 73% of families have no more than
50 species and 41 families (16%) are represented
by only one species.