IB Biology Topic A4.2.6 Causes of the Current Biodiversity Crisis Revision Notes (SL/HL)

IB Biology Topic A4.2.6 Causes of the Current Biodiversity Crisis Revision Notes (SL/HL) | RevisionDojo

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Human Impact: Population Growth Amplifies Resource Demand, Land Use, and Industrial Pollution

At the core of the biodiversity crisis is the exponential growth of the human population, now nearing 8 billion, up from less than 2 billion in 1920.
This growth amplifies:
1. Demand for resources (e.g., food, water, and energy).
2. Space consumption, leading to urban sprawl and deforestation.
3. Industrial activity, which depletes ecosystems and accelerates pollution.

Note

Although population growth itself is neutral, its associated activities amplify specific threats to biodiversity.

Direct Causes: Over-Exploitation, Habitat Loss, Pollution, Invasives, and Water Diversion

Over-exploitation: unsustainable use of resources
1. Hunting and fishing: Species such as the Atlantic bluefin tuna and the African elephant face drastic declines due to overfishing and poaching.
2. Deforestation for timber: Over-harvesting of keystone tree species disrupts forest ecosystems, threatening dependent species.
3. Medicinal and ornamental plant trade: Unsustainable harvesting leads to population declines of species like wild orchids.

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Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

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Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

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Human Impact: Population Growth Amplifies Resource Demand, Land Use, and Industrial Pollution

At the core of the biodiversity crisis is the exponential growth of the human population, now nearing 8 billion, up from less than 2 billion in 1920.
This growth amplifies:
1. Demand for resources (e.g., food, water, and energy).
2. Space consumption, leading to urban sprawl and deforestation.
3. Industrial activity, which depletes ecosystems and accelerates pollution.

Note

Although population growth itself is neutral, its associated activities amplify specific threats to biodiversity.

Direct Causes: Over-Exploitation, Habitat Loss, Pollution, Invasives, and Water Diversion

Over-exploitation: unsustainable use of resources
1. Hunting and fishing: Species such as the Atlantic bluefin tuna and the African elephant face drastic declines due to overfishing and poaching.
2. Deforestation for timber: Over-harvesting of keystone tree species disrupts forest ecosystems, threatening dependent species.
3. Medicinal and ornamental plant trade: Unsustainable harvesting leads to population declines of species like wild orchids.

Definition

Paywall

(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Note

Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.

Excepteur sint occaecat cupidatat non proident

Tip

Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.

A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics

IB Biology Topic A4.2.6: Causes of the Current Biodiversity Crisis Notes

A - Unity and Diversity9 subtopics

B - Form and Function10 subtopics

C - Interaction and Interdependence9 subtopics

D - Continuity and Change12 subtopics

Human Impact: Population Growth Amplifies Resource Demand, Land Use, and Industrial Pollution

Direct Causes: Over-Exploitation, Habitat Loss, Pollution, Invasives, and Water Diversion

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account

Human Impact: Population Growth Amplifies Resource Demand, Land Use, and Industrial Pollution

Direct Causes: Over-Exploitation, Habitat Loss, Pollution, Invasives, and Water Diversion

anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua

Duis aute irure dolor in reprehenderit

Excepteur sint occaecat cupidatat non proident

Unlock the rest of this chapter with a free account