2. Matrices methods
A matrix is a grid-like table that is used to
identify the interaction between project
activities, which are displayed along one
axis, and environmental characteristics,
which are displayed along the other axis
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3. How it works
Using the table, environment-activity
interactions can be noted in the appropriate
cells or intersecting points in the grid.
‘Entries’ are made in the cells to highlight
impact severity related to the nature of the
impact, for instance:
• Ticks or symbols can identify impact type
(such as direct, indirect, cumulative)
pictorially;
• Numbers or a range of dot sizes can indicate
scale; or
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4. Leopold interaction matrix
(1971)
• The Leopold matrix is the best known matrix
methodology available for predicting the impact
of a project on the environment.
• It is a comprehensive matrix, which has 88
environmental characteristics along the top
axis and 100 project actions in the left hand
column.
• Potential impacts are marked with a diagonal
line in the appropriate cell and a numerical
value can be assigned to indicate their 3
5. It is a two dimensional matrix
cross-referencing
•The activities linked to the project that are
supposed to have an impact on men and
the environment.
•The existing environmental and social
conditions that could possibly be affected
by the project.
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6. Three major groups of matrices
The environmental and social conditions
are divided in three major groups
• Physical conditions: soil, water, air
• Biological conditions: fauna, flora, ecosystems
• Social and cultural conditions: land use,
historical and cultural issues, populations,
economy
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