Environmental Assessment
Volume C-4.1
Slurry Pipeline
Flora
Ambatovy Project
82
January 2006
4.1.5.2 Assessment Criteria
Residual impacts were determined based on a classification system that
incorporates direction, magnitude, geographic extent, duration, reversibility and
frequency of the impact as described in Volume A (Section 7.4). Determination
of the overall environmental consequence uses magnitude, geographic extent,
and duration, and is described in Volume A (Section 7.4).
The assessment criteria used for plant communities are presented in Table 4.1-1.
Table 4.1-1 Impact Description Criteria for Plant Communities, Structure and
Diversity
Direction
Magnitude
Geographic
Extent
Duration
Reversibility
Frequency
neutral:
no
change
(a)
in plant
communities
negative:
a change
in plant
communities
negligible:
no
measurable effect on
plant communities
low:
<10% change in
plant communities
moderate:
10-20%
change in plant
communities
high:
>20% change in
plant communities
local:
effect
restricted to the
LSA
regional:
effect
extends beyond
the LSA
short term:
<3 years
medium
term:
3 to 30
years
long term:
>30 years
reversible or
irreversible
low:
occurs
once
medium:
occurs
intermittently
high:
occurs
continuously
(a)
Change in structure or composition.
4.1.5.3 Mitigation
Several mitigations are planned to reduce the magnitude, geographic extent, and
duration of direct impacts from the project on flora in the slurry pipeline LSA.
The main areas of mitigation include:
•
Maximize avoidance of native forest vegetation through pipeline
alignment design.
•
Establishment of research-based reclamation trials.
•
Reclamation using native species and effective soil treatments in
designated areas.
•
Reclamation strategies that support natural habitat restoration, where
this fits into local land use priorities (i.e., Mantadia-Zahamena corridor).
•
Rapid establishment of prescribed vegetation cover following pipeline
installation.
•
Careful consideration applied upon development of access routes, and
implementation of an access management plan in biologically sensitive
areas.
