Energy in Ecosystems Section 1.10

Energy in Ecosystems The source of all energy in ecosystems is the Sun. Sun YouTube - Bill Nye the Science Guy - 33 - Sun 3/3 The sun provides energy for green plants to make food (sugar) by photosynthesis http://www.brainpop.com/ (photosynthesis)

30% of the sun’s energy is reflected by clouds or the surface of the Earth 70% warms the surface of the planet, causing water to evaporate – fueling the water cycle and weather

Q/ A What is the source of all energy on the earth? How does this energy move through ecosystems? The sun is the source of all energy on the earth. The energy is transferred through ecosystems through plants (producers) then to animals that eat plants, or animals that eat other animals.

The Albedo Effect When sunlight hits an object, some of the energy is absorbed and some is reflected Some materials reflect sunlight better than others Albedo is a measurement of the percentage of light that an object reflects The higher the albedo, the greater the object’s ability to reflect sunlight

The higher the overall albedo is for Earth, the less energy that will be absorbed and available for maintaining the global temperature Snow has a high albedo effect – it contributes to low temperatures by reflecting energy back into space Snow delays warming in the spring

Other light coloured (high albedo) areas include sand, pale rocks, and areas without forest Cloud cover also increases the albedo of the Earth If there is more water vapour, or more dust for water vapour to condense on, there will be more cloud

Higher temperatures cause more water to evaporate (global warming) Industries release dust into the atmosphere http://www.brainpop.com/ (air pollution) Therefore global warming and pollution lead to a greater albedo effect

Classwork Pg. 22-23 What organisms would be affected if there were no mosquitoes? What is ecology? What are abiotic and biotic factors? What is a population? Give an example. What is a community? Give an example. What is an ecotone? Are ecosystems with greater biodiversity more or less fragile?

Biodiversity from Bill Nye http://www.youtube.com/watch?v=65w6IeMcdjo