Zonal Operations Cost Distance Analysis, Least Cost Path

Zonal Operations in GIS

In GIS, the land is divided into different zones or areas like forests, roads, water bodies, hills, etc.

Zonal operations help us analyze and compare things inside these areas, such as:

How far is something?
What is the easiest way to go somewhere?
How much effort does it take to move across different land types?

Now, let's focus on two important types of Zonal Operations:

Cost Distance Analysis in GIS

🧭 What is it?
It tells us how much "cost" (effort, time, or money) it takes to move from a starting point to other places in different zones.

🧒 Imagine this:
You are standing at your home and want to visit many places in your town.

Walking on a smooth road is easy (low cost).
Walking through a forest or hill is hard (high cost).
GIS shows a map of how hard it is to reach every location from your starting point.

✅ What it helps with:

Finding how difficult it is to travel through different areas.
Planning emergency routes or service delivery in disaster zones.

Least Cost Path Analysis in GIS

🚶‍♂️ What is it?
It finds the best and easiest path between two places by avoiding difficult or costly zones.

🧒 Imagine this:
You want to go from your home to school. There are many routes:

One is longer but flat and easy to walk.
Another is shorter but goes up a hill.

GIS chooses the route that takes less total effort — this is called the Least Cost Path.

✅ What it helps with:

Planning roads, pipelines, or electric lines.
Finding the shortest or safest route for walking or driving.

Concept	Meaning	Example
Cost Distance Analysis	Shows how hard or costly it is to reach different areas from one point	How much effort to go from your home to all other places
Least Cost Path	Finds the easiest or cheapest way between two points	Which route to take to school to avoid hills or traffic

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