3 Earth’s Environmental SystemsEarth’s Environmental SystemsC

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Lesson 3.2 Systems in Environmental ScienceLesson 3.2 Systems in Environmental Science

Positive feedback loops can help erosion turn a fertile field to desert in just a few years.

Dust storm, Stratford Texas, 1930s

Interacting SystemsInteracting Systems

Lesson 3.2 Systems in Environmental Science

• Inputs into Earth’s interconnected systems include energy, information, and matter.

• Feedback loops regulate systems.

• Negative feedback loops: Result in stabilization of a system

• Positive feedback loops: Result in a system moving to an extreme

Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on.

Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on.

Negative feedback loop

Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on.

Did You Know? Predator-prey cycles are negative feedback loops. If prey populations rise, predator populations can rise in response, causing prey populations to fall. Then predator populations may decline, allowing prey populations to rise again, and so on.

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Spheres of FunctionSpheres of Function• Earth can be divided into spheres that are defined

according to their location and function. • Earth can be divided into spheres that are defined

according to their location and function.

Lesson 3.2 Systems in Environmental Science

Geosphere, LithosphereGeosphere, Lithosphere

•Geosphere-made of rock and anything BELOW Earth’s surface.• Lithosphere-the hard rock on or below Earth’s surface•Biosphere-Consists of all living or once living things

thrived

•Geosphere-made of rock and anything BELOW Earth’s surface.• Lithosphere-the hard rock on or below Earth’s surface•Biosphere-Consists of all living or once living things

thrived

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Atmosphere & HydrosphereAtmosphere & Hydrosphere

• Atmosphere-all layers of gas that surrounds out planet•Hydrosphere-encompasses all water

• Ex. Great lakes are part of the Hydrosphere

• Atmosphere-all layers of gas that surrounds out planet•Hydrosphere-encompasses all water

• Ex. Great lakes are part of the Hydrosphere

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Crust, Mantle, & CoreCrust, Mantle, & Core

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