Geographic Information Systems for Management Information Systems

Definition of Geographic Information: Information concerning places, focusing specifically on the spatial dimension. It is noted that approximately $80\%$ of all information includes a spatial component. A central challenge in MIS is determining how to embed location within data.
Formal Definitions of GIS:
- Worboys (1997): A computer-based information system that enables the capture, modeling, manipulation, retrieval, analysis, and presentation of geographically referenced data.
- Functional Definition: A computerized tool used for solving geographic problems.
- Decision Support: A spatial decision support system.
- Operational Definition: A tool for automatically performing operations on geographic data.
The Hierarchy of Knowledge in GIS:
- Data: Raw geographic facts that are context-free.
- Information: The interpretation of raw geographic data.
- Knowledge: Interpreted information based on specific content, experience, and a defined purpose.

Questions GIS Can Answer:
- Resources Inventory: Identifying what resources are available and where they are located.
- Network Analysis: Determining the shortest amount of time or distance to reach a destination.
- Location Analysis: Identifying optimal locations for facilities (e.g., shopping malls).
- Terrain Analysis: Identifying natural disaster danger zones and performing visibility analysis.
- Spatial-Temporal Analysis: Analyzing changes at specific locations over time (e.g., the last $20$ years) and identifying the underlying causes.
The Six Components of GIS:
1. Hardware
2. Software
3. Data
4. People
5. Procedure
6. Network (Internet)
GIS Hardware Specifics:
- Primary unit: A computer.
- Peripherals: GPS devices, large format paper, printers, digitizers, and scanners.
GIS Software Examples:
- ArcGIS
- QGIS
- Google Earth

Vector Data Types:
- Point: Zero-dimensional coordinates.
- Line: One-dimensional features connecting points.
- Polygon: Two-dimensional enclosed areas.
Raster Data Types:
- Orthophotos
- Scanned maps
- Grids
Symbolization Variables:
- Maps use visual variables to represent reality, including size, color, shape, orientation, and texture.
- Qualitative Differences: Use differences in shape, texture, and hue (e.g., land use types).
- Quantitative Differences: Use size to show variation in count or amount (e.g., population count, crime incidents).
- Intensity/Ratio Differences: Use graytone or hue to show differences in intensity (e.g., population density, poverty proportions).

Core Uses in Agriculture:
- Farm planning and field mapping.
- Soil sampling and crop scouting.
- Monitoring crop health.
- Variable rate applications (VRA).
- Yield mapping.

Map Projections:
- Definition: The process of transforming the curved, 3-D surface of the Earth onto a flat, 2-D plane.
- Trade-offs: Projections inevitably distort map scale but can preserve specific properties like area or angles for small regions.
Scale Types:
- Ratio Scale: Expressed as $1:10,000$ or $1:100,000$ .
- Verbal Scale: Described in words, such as "One inch represents $2,000$ feet" ( $1:24,000$ ) or "One centimeter represents $20$ kilometers" ( $1:2,000,000$ ).
- Graphic Scale: A scale bar, which is easily interpreted and remains accurate even if the map is resized during publishing (newspapers, online).
Map Layout Metadata Requirements:
- Title
- Legend
- Scale Bar
- North Arrow
- Data sources and Date of creation

Graphical User Interface (GUI) Components:
- Menu Bar and Toolbars.
- Browser Panel (for file navigation).
- Layers Panel (listing project layers).
- Map Canvas (the central viewing area).
- Status Bar (showing Coordinate, Scale, Magnifier, Rotation, and EPSG code).
Working with Point Data:
- Importing points directly from GPS receivers.
- Utilizing pool satellite views.
- Managing attribute tables, labels, and symbology.
Working with Polygon Data:
- Importing tracks from GPS receivers.
- Digitizing features into shapefiles.
- Measuring area (both physically and via calculation).
- Measuring distance between Point A and Point B.
- Advanced editing: Splitting polygons and finding centroids.

Direct Access in QGIS (XYZ Tiles):
- QGIS includes built-in Access to OpenStreetMap via the "XYZ tiles" section in the browser window.
- New connections can be created for various Google Map layers using specific URLs:
  - Roadmap: $http://mt0.google.com/vt/lyrs=m\&hl=en\&x=\{x\}\&y=\{y\}\&z=\{z\}$
  - Terrain: $http://mt0.google.com/vt/lyrs=p\&hl=en\&x=\{x\}\&y=\{y\}\&z=\{z\}$
  - Altered Roadmap: $http://mt0.google.com/vt/lyrs=r\&hl=en\&x=\{x\}\&y=\{y\}\&z=\{z\}$
  - Satellite Only: $http://mt0.google.com/vt/lyrs=s\&hl=en\&x=\{x\}\&y=\{y\}\&z=\{z\}$
  - Terrain Only: $http://mt0.google.com/vt/lyrs=t\&hl=en\&x=\{x\}\&y=\{y\}\&z=\{z\}$
  - Hybrid: Combines Satellite and Roadmap layers.
Other Online Data Repositories:
- Natural Earth
- Open Topography
- World Bank Geodata
- Global Agriculture Lands
- Global Irrigated Area Map (GIAM)
- UNEP Environmental Data Explorer
- NASA Earth Observations (NEO)

Study Area Maps for Research:
- Administrative shapefiles can be downloaded for free from DIVA-GIS.
- Process: Download country-specific shapefile (e.g., Tanzania), import into QGIS, and perform map projection.
Soil Distribution Mapping:
- Source: FAO/UNESCO Soil Map of the World Shapefile.
- Process: Import world shapefile and extract specific regional data (e.g., Tanzania Soil Map).
Proportional and Thematic Mapping:
- Import shapefiles from the National Bureau of Statistics (NBS).
- Import tabular data from MS Excel.
- Use the Join function to link the attribute table with the Excel data.
- Project the map to show themes such as crop diversification levels by region (e.g., using crop fragmentation indices ranging from $0.58$ to $0.98$ ).