Environmental Assessment
Volume C-4.1
Slurry Pipeline
Flora
Ambatovy Project
87
January 2006
good quality amounts to 28 ha (5 ha of transitional forest and 23 ha of zonal
forest) while disturbed or managed forests amount to 88 ha (49 ha of degraded or
heavily logged forest and 39 ha of woodlot plantation).
To help mitigate the effects to native forest vegetation, 60 ha of the pipeline
corridor within regionally important habitat zones will be reclaimed to a forest
state using native species. This initiative will complement other reclamation
projects initiated by other organizations in the region.
Along sections of the pipeline where the reclamation goal is to achieve a grass
type vegetation cover, monitoring will continue until erosion risks are minimized.
In the sections designated for reforestation, monitoring will continue for a longer
period to ensure the trajectory of forest succession is proceeding along the desire
pathway.
4.1.6
Key Question FL-2 What Effect Will the Slurry Pipeline
Have on the Introduction of Exotic and Unwanted Plant
Species?
Roads (including access corridors associated with pipelines) contribute to
increases in the spread of exotic species (Trombulak and Frissell 2000). Edge
effects from forest clearings increases light which in turn increases the density of
adaptive or early successional species that prefer high light levels such as within
disturbance areas (Mehrhoff 1989). Exotic or unwanted (weeds) species
typically increase along disturbed forest edges as a result of preferred habitat
conditions, stressing or removing native species, and providing a contact zone for
dispersal (Trombulak and Frissell 2000).
4.1.6.1 Assessment Methods
Assessing the potential effects of the pipeline on exotic and unwanted species
(i.e., weeds) was done in a qualitative manner.
4.1.6.2 Assessment Criteria
The assessment criteria used for exotic and unwanted species are presented in
Table 4.1-4.
