GIS and EA Engr. Mansoor-Ul-Hassan Siddique Government of Pakistan
Formal Definition of GIS “ A system for capturing, storing, checking, integrating, manipulating, analysing and displaying data which are spatially referenced to the Earth. This is normally considered to involve a spatially referenced computer database and appropriate applications software� Chorley Report, 1987
What GIS can do? What would happen if . . . Achemical leaked into a riv er? Is there a correlations between . . . The location of cattle colony and the spread of water- borne disease Has . . . Population pattern changed ov er the last ten years? Is there a spatial pattern related to . . . Car ownership in our area?
GIS comprises of:
Tools to execute four operations on geo-referenced data:
Data input Storage Management Analysis Output
Type of Information
Spatial
Maps Post Codes Census Report
Management
Financial Statement EIA Guidelines Schematic Diagram
What is Spatial Data?
Grid co-ordinate
Place Name
Longitude -Latitude
Post Code
Distance and bearing
Numerical Data
Maps to Display Spatial Data
200’
Sta. 94, DOC 4.9
Stream,3 Former Land Fill
100’ FOREST
URBAN
FOREST
200’
100’
WELL
Duvall, pop 1170 AGRICULTURE
Snoqualmie River, 1
Brush Creek, 2
GIS Organizes Data in Layers Land use Soils Streets Hydrology Parcels
Sites of Ecological Importance
Overlaying Component Maps
Water Quality
Landscape Consideratio ns
Development A (e.g., Industrial Plant) Development B (e.g., road scheme)
Complete Composite Map
The Compilation of an Overlay Map from Various Component Maps
GIS System Architecture and Components
Data Input
Query Input
Output: Display and Reporting
Geographic Database
Transformation and Analysis
Use of GIS in Environmental Studies
Monitoring environmental risk
Modeling storm-water runoff
Management of watersheds, floodplains, wetlands, forests, aquifers
Environmental Impact Analysis
Hazardous or toxic facility siting
Groundwater modeling and contamination tracking
Features of GIS for EA
Description and distribution of natural resources
Identification of environmental stress
Description of project stress
Assessment of response
Risk assessment
Assess effectiveness of mitigation measures