Assessment, Conservation and Sustainable Use of Forest Biodiversity

Assessment, Conservation and Sustainable Use of Forest Biodiversity
Within each plot, one corridor was randomly selected. Each corridor was characterized with respect to
management and design (condition, width, degree of connectedness to other green belts, distance to
conservation areas, vertical structure, tree species composition, herbal/shrub composition). Biological surveys
were conducted within the 100 ha plots.
Profitability of the entire concession was also assessed based on stand and sector level data.
Results
Profitability of plantations
The profitability of the plantation concession increased as an increasing proportion of the concession was set
aside and retained as natural forest corridors, until a threshold of 25-30%, above which the profitability
rapidly declined.
Both pest incidence and the area damaged by wind, within plantation stands declined with increasing
proportion of the concession set aside as natural forest corridors. Other factors, including fires and invasives,
were of negligible economic impact upon the profitability of the plantation concession.
Interests of local communities
The density of the ten most important tree species currently used by local communities for non-timber
purposes, increased linearly with increasing proportion of the concession in natural forest corridors.
Conservation of biodiversity
Density of primates, and number of primate species, both increased, initially linearly, and then asymptotically
approached the maximum of the region as a whole, with increasing proportion of the concession set aside and
retained as natural forest corridors. At 25-30% of the concession in natural forest corridors, 85-90% of the
primate species and density thereof had been retained. Connectivity of corridors to other corridors and to
larger areas of natural forest was critical: corridors not connected to other larger patches of natural forest,
hosted no primates.
Discussion
Appropriate design and management of natural forest corridors and remnant patches can be used to mitigate
or reduce the negative impacts of large-scale industrial plantations on native biodiversity and towards
maintenance of environmental and social functions of the original natural forest landscape.
The ecological and environmental services have substantial impacts on the profitability of the plantations.
Recommendations and Lessons Learned
First, plantation landscapes should be designed so that on the one hand, the landscapes are penetrable and
permeable for those biodiversity components which are of conservation concern in the area under
consideration, and on the other hand, impenetrable and impermeable for pests, weeds, and invasives. Second,
from a human/social standpoint, priority must be to design plantation and manage landscapes in a way that
minimizes the adverse impacts on the local people and communities living in and around these areas. This
includes the importance of natural forests for the livelihoods of local people, both in terms of the resources that
they can obtain from those areas, and from the environmental services, e.g., maintenance of good water quality.
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