Correct option is D
The correct answer is (d).
Introduction
Overlay maps are a highly visual, easy-to-understand, and popular method in Environmental Impact Assessment (EIA).
They utilize spatial mapping to superimpose various environmental attributes, making complex geographical and ecological impacts instantly comprehensible to decision-makers and the public.
Information Booster
- Overlay maps traditionally involved physical transparent sheets, each representing a different environmental parameter (e.g., wetlands, forests, residential areas).
- By stacking these sheets, areas of high environmental sensitivity or conflict become visually darker or distinctly highlighted.
- Modern overlay mapping is exclusively driven by Geographic Information Systems (GIS), dramatically enhancing its accuracy and data integration capabilities.
- It is exceptionally effective for route selection (like highways or pipelines) and site suitability analysis.
- The method excels in communicating spatial impacts to non-technical stakeholders during public hearings.
- Ian McHarg is historically credited with popularizing the overlay method in his seminal 1969 book, 'Design with Nature'.
- Checklists are simple lists of potential impacts but lack spatial dimensions and fail to show relationships between different environmental components.
- Network methods use cause-condition-effect flowcharts to trace secondary and tertiary impacts, making them highly complex and harder for laypersons to interpret.
- Matrices (like the Leopold Matrix) cross-reference project actions with environmental components in a grid, which is comprehensive but can become overwhelmingly large and visually dense.
- Historically, the National Environmental Policy Act (NEPA) of 1969 in the USA was the legislative catalyst that necessitated the development of these various EIA methodologies.
English
10 Questions
20 Marks
12 Mins
