FR3131/5131 Introduction to GIS in Natural Resource Mangement

1
Geography 241 GIS I
Dr. Patrick McHaffie Associate Professor Departmen
t of Geography
Cook County, population lt 5
2
What is a GIS?

• Geographic Information System - collection,
  organization, maintenance, analysis, and output
  of spatially-referenced information.
• Two important components - What, and Where

3

• We usually understand GIS to be
  computer-facilitated system
• GIS is NOT only software/hardware
• Also includes
• Trained personnel
• Supporting Institution
• Protocols for use

4
GIS Hardware Typical of most computer systems,
with a little more storage, a few added tools for
input/output. Coordinate input devices are the
primary specialized hardware. Digitizing
Tablets GPS receivers.
5
GIS Software
6
What is in it for me?

• Take a sheet of paper, put your name and major at
  the top. Then,
• In a five minute free write, answer the question
  
• How can you imagine you might be using GIS and
  other Geotechnology in 5 years?

7
phenomena that exist
computer representation
An abstraction, relevant phenomena and properties
8
REPRESENTATION AND DATA STRUCTURES Coordinates
and Attributes
9
Many objects for a theme, with properties
recorded for each object
10
REPRESENTATION AND DATA STRUCTURES

• Most common data models define thematic layers
• Typically, layers, one layer for each distinct
  view of a theme

11
Cartesian Coordinates
12
(No Transcript)
13
(No Transcript)
14
Common Data Models
15
Vectors Define Discrete Features
16
Three Types of Vector Features
17
Vector Topology
Topology geometric properties that to not
change with shape Adjacency,
connectivity, containment
18
Rasters Fixed Cell Size, Grid Orientation
19
Rasters Discrete or Continuous Features
discrete
continuous
20
Raster The Mixed Pixel Problem
Landcover map Two classes, land or water Cell
A is straightforward What category to assign For
B, C, or D?
21
Summary

• GIS are systems for the creation, maintenance,
  analysis, and conveyance of spatial data
• We represent abstractions of our world into
  spatial and attribute components using data
  models and data structures
• Two major data models raster and vector