Environmental Assessment
Volume B-4.1
Mine
Flora
Ambatovy Project
158
January 2006
indirectly affected by the project from the encroachment of exotic or unwanted
species. The project also has the potential to result in plant species loss (species
extirpation and extinction).
These effects are primarily the result of construction and operation activities.
Positive effects to flora are expected as a result of closure activities and
implementation of the mitigation strategy. All project-related effects to flora
may have implication for visual aesthetics, land use, fauna, human and ecological
health and biodiversity. Where issues are related (e.g., loss of plant communities,
community structure and plant diversity), they are analyzed and discussed
together to avoid repetition. A linkage diagram for flora issues is shown in
Volume H, Appendix 9.
4.1.5
Key Question FL-1 What Effect Will the Mine Have on
the Loss or Alteration of Plant Communities, Structure
and Diversity?
During construction and operation phases, flora will be directly disturbed through
the clearing of vegetation.
4.1.5.1 Assessment Methods
Impacts of the project on the loss or alteration of flora is assessed through
changes in the total area of vegetation types. Direct effects relate to site clearing
while indirect effects are related to fugitive dust and SO
2
and NO
X
emissions,
changes in water levels and changes in water quality.
Effects of Clearing Activities
The project footprint includes the core mine area (e.g., site facilities, roads, pits
and waste rock storage areas) and water intake pipeline. Core mine site
disturbances include a 50 m buffer to account for vegetation edge effects and the
water intake pipeline was buffered by 25 m to account for construction impacts
(i.e., spoil side and work side of pipeline).
Potential impacts to forest structure and diversity are assessed on the basis of the
total change in the area of vegetation types. Forest structure is defined by the
dominant strata of the vegetation type (i.e., forest, thicket or non-forest) and
moisture conditions (upland or wetlands). A conservative approach was taken to
assess plant diversity. All natural vegetation types were assigned a high diversity
class and assessed according to loss of area.
