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RESULTS AND
DISCUSSION
The results presented below summarize the
findings from the surveys conducted in the
four target countries: Cameroon, Gabon,
RoC, and DRC. Here we present information
relevant to setting reference emission levels
for REDD+ activities by determining historical
deforestation rates in mangroves, providing
an analysis of drivers of deforestation and
degradation
of
mangrove
ecosystems,
estimating values of ecosystem services and
presenting carbon stocks, sequestration
as well as potential emissions. Having
accurate estimates of these metrics can help
governments in making the case for the
inclusion of mangroves in national REDD+
plans and can allow for improved monitoring,
reporting and verifications necessary for
REDD+ activities in the region.
Mangrove area change (2000 –
2010) and analysis of drivers
Mangrove area change (2000 – 2010)
The following data are presented with some
important caveats that must be taken into
account when interpreting the results. Firstly,
the relatively low 30m spatial resolution
Landsat imagery from which the mangrove
classifications were derived does not allow
for identification of very localized small-scale
(<30m) deforested patches common in many
mangrove areas. This does not allow us to
qualify the quality of the ecosystem in terms
of density and height of trees. A forest may
have been degraded and thinned to some
degree but not completely deforested and this
may not be evident from the satellite images
analysed here. Furthermore, the Congo River
Basin has extremely high levels of cloud cover,
thus making access of cloud-free images for
the region difficult. To generate cloud free
coverages for the area of interest, images
from years preceding and following the study
years were acquired, usually 3 in total, and
merged together in a process which selected
the best quality pixels from all 3 images, again
decreasing the accuracy of analysis. Finally,
although the satellite images and derived
mangrove classifications were validated by
an expert in the field, a far greater amount
of validation is recommended to increase
confidence in the results and improve the
accuracy of our analysis. Validation by experts
in each country rather than one for the whole
region would be highly beneficial.
However, even given these caveats, some
interesting trends do emerge from the analysis.
Deforestation rates are high, with 18% loss
between 2000 and 2010 in Cameroon, 35%
loss in the RoC, 6% loss in the DRC and 19%
loss in Gabon. The overall rate of loss per year
for the region is high, 18% over the decade, so
1.8% loss per year. However, along with these
fast rates of loss the analysis also found areas
of regrowth and resilience, meaning that the
overall net loss was relatively insignificant.
Cameroon exhibited 0.5% net loss, RoC 2.5%,
DRC 1.6%, Gabon 2.7% and the overall region
1.6%. As stated above this net loss does not
take into account degradation and thinning of