1. Air Photo Interpretation
Feature Identification
Shape
Cultural features
-some features such as airport runways have distinctive shapes which make them easy to identify
-roads are usually regular in shape which tends to make them easy to identify
-railways are also of uniform width and have long, straight stretches and more gentle curves than roads
-bridges should be looked for wherever roads or railways cross a body of water; they are generally of uniform width, and will often cast a shadow that reveals their structure
-buildings have a variety of regular shapes that vary considerably in size depending upon the use of the structure

2. Air Photo Interpretation
Natural features
-generally have more irregular shapes
-quite east to tell the difference, for example, between an orchard (rows of trees with regular spacing) and a forest area with irregular tree growth
Pattern
-formed by the repetition of a feature e.g. farm fields, rows of trees in an orchard, oil storage tanks at a refinery
Shadow
-high objects such as towers, chimneys, bridges, or high buildings cast shadows which help you to identify the object
-shadows can help one to tell the time of day that the photo was taken

3. Air Photo Interpretation
Tone
Cultural features
-roads and tracks will usually have a light grey tone as they are fairly reflective of light
-railways: medium grey bridges vary according to construction material

4. Air Photo Interpretation
Natural features 
Water
-generally appears dark grey or black since it absorbs much of the light
-if the water body is fairly shallow with the light coloured or weedy bottom, or if it carries a high silt load, it will reflect more light and appear lighter in color
-rough water has many reflective surfaces so it may range form dark to almost white
Vegetation
-most will vary from shades of grey to black
-since deciduous, broad leafed trees reflect more light than coniferous trees, they appear in lighter shades

5. Air Photo Interpretation
Soil
-bare ground usually has a light colour but the wetter it is, the darker the tone
Crops
-cultivated fields and fallow fields are almost white in tone
-well developed crops will be dark grey but tones vary according to the season, type of crop, and stage of growth
General guide
Spring: sharp, distinct field patterns due to differences in tillage and crop development
Summer: dark tones for maturing crops and heavily leafed trees
Fall: distinct field patterns because of the various stages of crop development and harvesting
Winter: when there is little or no snow cover, tones are generally drab and dull

6. Air Photo Interpretation
Location
-refer to a topographic map to locate the area shown in the air photo. Often compass directions are not given on an air photo therefore if you are required to find a particular direction on an air photo; you will need to utilize an accompanying topographic map.
Scale
-refer to notes

7. Air Photo Interpretation
Physical features
Broad patterns
-look at the whole photograph to get a general picture of the area
Drainage
-describe the distribution of lakes, rivers,, and streams, and general drainage conditions
Natural vegetation
-determine the approximate percentage of the area which is covered by natural vegetation

8. Air Photo Interpretation
Soils
-if field patterns are obvious, a determination of the crops grown could indicate particular soil types
Climate
-use information about drainage, vegetation and soils to make inferences about the climate (topographic map will help)
Settlements
-how many settlements are there?
-where are they located?
-how are they distributed (i.e. clustered, scattered, regularly or irregularly spaced)

9. Air Photo Interpretation
Transportation and Communication 
Roads
-What variety of roads are found (i.e. dual highways, single highways, paved, gravel, etc.)?
Airport
-Where is it located in relation to any visible settlements?
-How long are the runways?
Other
-are there hydroelectric transmission lines, telegraph or telephone lines?
-are there any communication towers visible?
-how do these features relate to physical and cultural patterns?

10. Air Photo Interpretation
Economic activities
-note any evidence of fishing, forestry, mining or quarrying, manufacturing, recreation or tourism, or agriculture and its distribution
- establish any relationships between economic activity and the physical and cultural features of the area.

11. Air Photo Interpretation
A) New Glasgow
1) golf course
2). At L8, the water colour is lighter due to a higher sediment content as the river enters the ocean and deposits its load. The water is also probably shallower at that point. The lighter colour is due to greater reflection of light.
3) B1
4) Farming – plots of land are visible with some fields recently cultivated or left fallow (whiter) and some more developed crops (darker tones).

12. Air Photo Interpretation
B) St. John’s
1) B. When you find the same spot on the topographic map, you will find the word “Oil” and storage tanks are visible in the air photo.
2) nucleated / built up area / highly urbanized
3) sports track
4) white streaks
5) G5 and G6

13. Air Photo Interpretation
C) Beloeil
1) golf course
2) seigneurial system (French): long narrow strips of land often perpendicular to a river or stream. These plots of land have been divided over time from one family generation to the next. Make sure that you look at the topographic map to get the information that this community is in Quebec.
3) A. Orchard symbol on the topographic map and not a cultivated field (N8) like the others on the air photo.
4) What is located at O9 / P9 on the air photo? Qarry. See 3046 on topographic map.

14. Air Photo Interpretation
Modifications
Implications
Agriculture (eg southeast and northeast portions of the air photo)
-Use of fertilizers and pesticides alters the soil content and may threaten water quality in streams, groundwater, and perhaps even the reservoirs near The need for irrigation water. Perhaps water is being drawn from those reservoirs. - Growing of food for the benefit of human health.
Golf Course
( / H6)
- Use of fertilizers and pesticides may threaten water quality in streams and groundwater. - Green space is maintained.
Urbanization (eg Sainte-Julie, Domaine- des-Hauts-Bois, Saint-Bruno De Motarville, and Saint-Basile-le-Grand) and Transportation Routes (eg Highways 102, 30, and 116)
- Urban runoff into streams and rivers, sewage disposal issues, air pollution from vehicles, drinking water supply needs (eg filtration plant near Lac de Moulin 3044)

15. Air Photo Interpretation
Conservation Park (i.e. Parc De Conservation Du Mont-Saint-Bruno)
- Protected forested area to filter air pollution and prevent erosion on hill slopes which also helps to protect water quality in lakes. These green spaces also provide areas for recreation which benefits human health.
National Defence Area (3247)
- Military equipment and training may disrupt natural habitat and disturb wildlife
Quarry (3046)
- Mass digging alters the natural ecosystem; rehabilitation of the land may be necessary.