一根线条
Use netlogo to simulate Desertification
D1, Category A
谢余子馨 1709853V-B011-0140
王梓石 1709853P-B011-0090
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Contents
Background
Simulation Methods
Research Question
Data Generated
Finding and Conclusion
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Part one
Background
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Desertification has always been one of the threats of the world. Desertification refers to the total process of natural environment degradation in arid, semi-arid and even semi humid areas due to the comprehensive effect of human and natural factors.
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The total area of deserts, Gobi and desertified land in China is about 1.308 million square kilometers, accounting for 13.5% of the total land area.
Up to now, the national forest coverage rate has reached 22.96%, and the forest area has reached 220 million hectares.
forest：deserts≈2:1
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Part two
Research Question
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02
Research Question
Our group’s main idea is to implement the simulation of desertification.
Afforestation can alleviate the desertification.
Desertification can reduce the number of living creature.
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Part three
Simulation Method
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03
Simulation Method
Our group designed several variables.
Number of sheep
The speed of sheep eating grass
The possibility of grass recovery
The number of people
The capacity of people planting trees
The capacity of people planting grass
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Our group designed two situations
Overgrazing and natural invasion of desert
Afforestation
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Simulation Method
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Part four
Data Generated
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Condition： Grass self-recover ability 0.5/0.5
Grass decrease slowly
Desert increase slowly
No. of sheep is decreasing 99👉77
No. of trees is decreasing 100👉94
preliminary stage
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Condition： Grass self-recover ability 0.5/0.5
Grass area decrease suddenly
Desert area increase suddenly
No. of sheep is decreasing 99👉77👉66
No. of trees is decreasing 100👉94👉90
Intermediate stage
0.1/0.5
0.2
0.1
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Condition： Grass self-recover ability 0/0.5
Grass area decrease significantly
Desert area increase significantly
No. of sheep is decreasing
No. of trees is decreasing
Last stage
0.1
0
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Grass decrease slowly
Desert increase slowly
No. of sheep is decreasing
No. of trees is decreasing
Before afforestation
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Grass increase significantly
Desert decrease significantly
No. of sheep stop decreasing
No. of trees is increasing significantly
Start afforestation
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Part five
Finding and Conclusion
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If people do not protect the green plants and do not take some actions to expand the green plants, then in a few years, the desert will spread to a large area.
But by planting trees and protecting green plants, people can effectively alleviate desertification, even reduce the area of deserts, and make the world more beautiful.
Conclusion
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THANKS
2020
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