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By Marc Cadotte
A Canadian mining corporation,
QIT-Fer et Titane, Inc., will be sponsoring a large-scale mining project
in the extreme south eastern region of Madagascar. The project will
result in the removal of much of the remaining coastal littoral rain
forest.
The QIT-Fer mining
project will be centred around the city of Fort Dauphin (or Tolagnaro)
in the extreme south eastern coast of the Island (Fig 1). This region
is significant as much of the habitat diversity that Madagascar is famous
for, is concentrated in this region (Goodman 1999). During a 50 km drive
along Route Nationale 12, one can see coastal marine areas, coastal
littoral forest, montane rain forest, dry deciduous forest, and the
unique spiny desert.
 QIT-Fer
will be mining for ilmenite (or titanium dioxide), used primarily in
the production of paints, paper, and plastics. This project may involve
the removal of 2540 Ha of littoral forest, or 73% of the remaining south
eastern coastal forest, leaving only about 940 ha of highly fragmented
and isolated forest patches along a 100 km stretch of coast. The clearing
of the forest on the proposed mining project will undoubtedly have some
profound consequences. Using the species-area relationship, S = cAz
(MacArthur and Wilson 1967) we can predict that a 73% decrease in natural
forest could entail up to 30% of species becoming locally extinct. Most
affected will be the highly localised endemics, which could vanish forever.
For example, in the mining region at least 18 species of tree and shrub
are found nowhere else on the island (Dumetz 1999), and one Gecko species
(Phelsuma antanosy) lives primarily in the to-be-cleared forests of
the southeast (Nussbaum et al. 1999).
 It
is unavoidable that biodiversity will be lost at many levels, from genetic
variation of populations to specific communities that form the littoral
forest ecosystem. As a result of further fragmentation will, through
metapopulation level effects, increase the probability that local populations
will go extinct (decreased patch size) while the probability of immigration
saving an imperilled local population will decrease (increased isolation)
(Wilcox and Murphy 1985; Gilpin and Hanski 1991). Increased fragmentation
will also increase the perimeter-to-area ratio, which is synonymous
with the injurious "edge effects". Increasing the edge effects by increasing
fragmentation can result in increased tree mortality and reduced biomass
within 100m from the edge (Laurance et al. 1998), increased intrusion
by exotic species, predators, or parasites (e.g., Wilcove et al. 1986),
as well as increased wind penetration and temperature, and decreased
humidity (Biorregaard et al. 1998). Once fragments fall below 100-400
ha in size, these effects can be greatly exacerbated (Laurance et al.
1998).
These are the consequences of straight out habitat destruction, but
there have been indications put forth by QIT-Fer that they will undertake
a restoration programme after the mining project. Much of the land cleared
in Madagascar has been severely denuded as to preclude any chance of
successful restoration projects (Terborgh and Van Shik 1997). Fig. 2
shows cleared land in the region of St. Luce to be included in the proposed
conservation area; exposed white sand indicates that no top soil remains
and only a few hardy species thrive in this environment (especially
Philippia sp., Ericaceae). Impediments to restoration of complex tropical
ecosystems include: many intricate evolved mutualisms between all types
of organisms, long intervals of time required for many tropical trees
to recover, and invasive species commonly acquire a foothold in disturbed
habitats. Similarly, many tropical forests represent communities which
may be impossible to put back together, despite all our knowledge and
efforts (Pimm 1994). Another caveat to the issue of restoration is the
cost, Vianne et al. (1997) found that the cost to restore a degraded
9.5 ha patch of rain forest in Brazil was $2,718.50 (U.S.), and this
price only included planting, enrichment and vine control. However,
the calculation of this cost did not include fire suppression, nor control
of resource extraction or hunting. This value translated into the hundreds
or thousands of hectares to be restored, equates to a large financial
commitment by a private interest.
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