"Ecosystem Stability" PPT download

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"Ecosystem Stability" PPT download

Part One: Introduction of New Course

Gardening staff planted a piece of grass in a corner of the park. In order to prevent birds from eating grass seeds, they covered the grass with a net. After a while, they found that the grass in the net was eaten by insects. Everyone doesn’t understand what’s going on. Do you know the reason?

learning target

1. Tell us what ecosystem stability is.

2. Outline the reasons why ecosystems have certain stability.

3. Briefly describe the reasons why ecosystem stability is destroyed.

Ecosystem Stability PPT, Part 2: Ecosystem

1. The ecosystem has a certain degree of stability

What organisms might live in grassland ecosystems? What's the connection between them?

Discussion and analysis

1. This year there is abundant rain, suitable temperature, and lush grassland plants. How will the number of rabbits change?

2. Will the number of rabbits increase indefinitely? Why?

With the help of the food chain, organisms restrict each other and maintain their quantity and proportion at a certain level - the self-regulating ability of the ecosystem

Are there similar regulatory processes in other ecosystems?

ecosystem stability

After a long-term development process, the ecosystem has gradually formed a relatively stable and balanced state between biological and non-biological substances and energy, and between organisms and organisms. This is the stability of the ecosystem.

2. The self-regulating ability of the ecosystem is limited

Cutting down a moderate amount of trees in the forest will not destroy the structural functions of the forest.

Moderate fishing of marine fish will not lead to a reduction in fish populations, let alone extinction.

Keep an appropriate amount of livestock on the grassland so that the grassland will not be destroyed.

The self-regulatory ability of the ecosystem is limited. When external interference factors exceed this limit, the ecosystem will lose its self-regulatory ability, causing stability to be destroyed.

Ecosystem Stability PPT, Part 3: Feedback in class

1. Among the following ecosystems, the one with the weakest self-regulation ability is ( )

A. Natural deciduous forest B. Natural evergreen forest

C. Artificial pure forest D. Artificial mixed forest

2. Corn borers reproduce in large numbers in the fields, causing serious reductions in corn yields. The reasons for the destruction of the stability of the farmland ecosystem may be ( )

A. Destroy the food chain

B. Cleared a large number of weeds in the field

C. A large number of voles were killed

D. A large number of weasels were hunted and killed

Keywords: Free download of Biology PPT courseware for the second volume of the eighth grade edition of Beijing Normal University, PPT download of the stability of the ecosystem, .PPT format;

For more information about the PPT courseware "The Stability of Ecosystems Ecosystems and Their Stability", please click the Stability of Ecosystems ppt Ecosystems and Their Stability ppt tag.

"Stability of Ecosystems" PPT courseware download:

"Stability of Ecosystems" PPT courseware download Part One Content: Classroom Thoughts Thinking: In an ecosystem, organisms such as wheat, rats, and bacteria live. Assuming better climate conditions and a large increase in wheat, how will the number of rats change? Ecosystem development..

"Stability of Ecosystems" PPT courseware:

"Stability of Ecosystems" PPT courseware Part 1: Self-study examination 1. What is the stability of ecosystems? After a long-term development process, the ecosystem has gradually formed a relatively stable balance between biological and non-biological substances and energy, and between living things.

"Ecosystem Stability" PPT:

"The Stability of Ecosystems" PPT Part One Content: Learning Objectives 1. Tell what the stability of ecosystems is. 2. Outline the reasons why ecosystems have certain stability. 3. Briefly describe the reasons why ecosystem stability is destroyed. ... ... ... ecosystem..

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Update Time: 2024-11-18

This template belongs to biology courseware Beijing Normal University Edition Eighth Grade Biology Volume 2 industry PPT template

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