This document discusses flow line maps and their use in visualizing migration patterns in and out of Nepal. It defines flow line maps as a type of thematic map that represents the movement of objects between areas using lines or arrows of varying widths proportional to statistical values of movement. The document outlines the objective, methods, and results of creating flow line maps to show the migration of Nepalese students abroad for study, Nepalese migrating abroad for work, and tourist arrivals in Nepal. It discusses advantages such as illustrating the volume and direction of movement, and disadvantages like potential distortion of distance and direction for visual clarity.
3. Thematic map…….
Involves maps of specific geographic themes, oriented toward
specific audiences.
Show a particular theme
Other irrelevant information is filtered out.
Shows the distribution and the thematic characteristics of one
phenomenon(or several phenomena )
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4. Flow line map……
A type of thematic map used in cartography to show
the movement of objects between different areas.
Directions and/or routes of movement are represented
by lines / arrows of varying widths
Represent the movement of good whether
phenomena, people and other living things with line
symbol of different order.
The width of each line / arrow is proportional to the
statistical value of the movement along it.
Can also show both qualitative and quantitative data
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5. Flow line map (contd…)
In qualitative flow mapping, the symbols are of uniform
width and typically are arrows.
In quantitative flow mapping, the cartographer selects a
line symbol and alters its width based on the data values.
When employing this technique, flow lines should be
symbolized so they are distinct from the background
information/base map.
When properly designed, flow maps are beneficial because
they allow cartographers, GIS analysts and map users alike
to easily see the differences in magnitude of a wide variety
of items across space with very little map clutter.
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7. Objective of flow line map…
To show the flow line visualization of the
following:
Nepalese students migrated abroad
countries for study.
Nepalese migrated to abroad countries for
working
Tourist arrival in Nepal
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16. Advantages of flow line map
Show the movement of people, goods, transport etc.
Can also show volume and direction of movement.
General information about what is flowing and how it is
flowing.
Good for mapping the movements of variables
How much is flowing, being transferred, transported,
etc.
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17. Disadvantage of flow line map
In order to achieve a clear image , the distance and direction
may be distorted
Not possible to read exact size data very easily as size category
are normally used.
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