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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?

Vegetation

  • 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?

Farming

  • 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?

Settlements

  • 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.

FIELD OBSERVATION

Position of site :

P roblem:

Aids used in investigation :

Findings :

Suggested solution :

N ames of group members:

Assessment

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

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
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
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
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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