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Black, white and grey tints can be seen on aerial pictures. The tint depends on the amount of light that is reflected by the photographed object. Light colours appear as light grey and dark colours as shades of darker grey.

The tint of water varies between white and black. Clear water appears darker than muddy water, because muddy water reflects more sunlight. Humid soil surfaces also appear darker than sandy soil.

Vegetation can be divided in two types according to their appearance on aerial photos:

  • Natural vegetation like forests and grasslands is easy to identify due to their diverse pattern. Trees usually have dark tints.
  • Planted trees and agricultural crops are also easily identified by the straight lines in which they are planted. The tint of a cultivated land depends on the height of the plants. For example, maize-fields with tall plants will appear darker than fields with small plants, because the tall plants absorb more sunlight than the small ones. Cultivated land usually has a patchwork quilt appearance of darker and lighter tints.

Gradients facing the sun reflect more light and therefore appear lighter than those with a southern gradient.

  • Texture of objects

It refers to the general impression that objects make and can be described as SMOOTH, FINE, COURSE, ROUGH or DOTTED. Photos of cultivated land and water show a fine, smooth appearance. Shrubs and forest vegetation has a dotted appearance, whereas uninhabited mountainous areas have a rough appearance.

  • Shadows

Aerial photos are usually taken between 10:00 and 14:00 when shadows are at their shortest. Shadows are of great help in identifying objects. Shadows that fall outwards indicate a higher area such as a hillside, mountain, or high building, whereas shadows falling inward indicate lower lying areas such as riverbeds and excavations.

  • Patterns

When analysing aerial photos, much information can be obtained from patterns. Certain patterns are characteristic of specific objects and phenomena. Bushveld vegetation has a diffused pattern, but citrus orchards or vineyards have linear patterns.

The arrangement of buildings and streets show a typical urban settlement pattern. The older, central business centre has a grid pattern, and the newer residential areas appear to have rather concentric patterns.

We therefore have two main pattern types that can be identified on an aerial photo:

  • the physical landscape, and
  • the cultural landscape.
  • Tips for reading, analysing and interpreting vertical aerial photos and orthophoto maps
  • Mark the general patterns that clearly appear on the photo. It is usually done by placing trace paper on the photo and then the profiles of the patterns are traced. The different characteristics are named.
  • Carefully study the shape, size, shadow, tint, and texture of the related characteristics to identify objects.
  • Ask certain kinds of questions that can assist in identifying objects:

Relief characteristics

  • Are there mountains, hills and valleys?
  • How steep are the slopes?
  • Are there any rivers?
  • How wide are the river valleys or plains?
  • In which direction does the river flow?
  • Is the river perennial or non-perennial?


  • Which types of vegetation exist?
  • Which areas are covered with natural vegetation?

Transport systems

  • Which types of transport occur?
  • Which types of roads criss-cross the photo?
  • Are the railway lines single or double lines?


  • Do they farm with livestock or is it crop farming? Or both?
  • What is the size of the cultivated land?
  • What kind of crops are grown?


  • What types of buildings can be seen in the urban areas?
  • What is the layout of farmsteads and outbuildings?
  • Are there any industries? If so, which types?

Activity 1:

To identify and interpret information on a topographic and orthophoto map of the known environment

[lo 1.4]

  • Your teacher will hand you a 1:50 000 topographic map and an orthophoto map of your area. Try to apply all the knowledge that you gained from the previous pages by answering your teacher’s questions.

Activity 2:

To identify a problem on an orthophoto map and to compare it with the real situation

[lo 1.4, 1.5]

  • First work individually and then in your groups. Try to identify a problem that appears on the orthophoto map of your environment. If no problem exists, try to identify a potential problem, such as a flood, landslide, fires, erosion, the need for reservoirs, poor road or street planning, etc. Suggest a solution to the problem.

Activity 3:

To investigate an identified problem during a fieldwork excursion and to write a report on it

[lo 1.6]

  • If possible your teacher will organise a fieldwork excursion to visit the site of such an identified problem. Collect data by making use of maps, drawings, photos, etc. After the excursion each group must write a report on their findings and also suggest a solution for the problem. The report must be written in the space below.


Position of site :

P roblem:

Aids used in investigation :

Findings :

Suggested solution :

N ames of group members:


Learning Outcomes(LOs)
LO 1
GEOGRAPHICAL ENQUIRYThe learner will be able to use enquiry skills to investigate geographical and environmental concepts and processes.
Assessment standards(ASe)
We know this when the learner:
1.1 identifies a variety of geographical and environmental sources relevant to an inquiry [finds sources];
1.2 organises and interprets information relevant to the enquiry from simple graphs, maps, and statistical sources [works with sources];
1.3 measures distances on globes atlases and maps using line scales [works with sources];
1.4 uses local maps and/or orthophoto maps to locate and investigate the issue and its context (compares with field observations) [works with sources];
1.5 uses information to suggest answers, propose alternatives and possible solutions [answers the question];
1.6 reports on the inquiry using evidence from the sources including maps, diagrams and graphics; where possible uses computers in the presentation [communicates the answer].

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Geography grade 7. OpenStax CNX. Sep 09, 2009 Download for free at http://cnx.org/content/col11021/1.1
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