How Ecosystems Work Chapter 5

Energy flow in the Ecosystem Life depends on the sun in a process called photosynthesis Plants, algae and some bacteria capture solar energy and with Carbon Dioxide CO2 and Water H2O make Oxygen O2 and sugar or glucose C6H12O6 6CO2 + 6H2O + sun = C6H12O6 + 6O2 All organisms ultimately get their energy from the sun

6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 + 6O2 Energy Flow Through an Ecosystem Begins with the SUN Photosynthesis 6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 + 6O2 http://sps.k12.ar.us/massengale/biology

Producers use most of the energy they make for themselves. Organisms that can make glucose during photosynthesis are called Producers use most of the energy they make for themselves.

http://sps.k12.ar.us/massengale/biology The energy that is not used by producers can be passed on to organisms that cannot make their own energy.

Organisms that cannot make their own energy CONSUMERS Organisms that cannot make their own energy http://sps.k12.ar.us/massengale/biology

Consumers eat producers to get energy: Most of the energy is used by the consumer but some of the energy moves into the atmosphere as heat. Consumers eat producers to get energy: Herbivores- eat plants Omnivores – eat Plants and animals Carnivores – eat animals http://sps.k12.ar.us/massengale/biology

An Exception to the Rule: Deep Ocean Ecosystems Hydrothermal Vent Bacteria use Hydrogen Sulfide from the hot water to make their own food Thus they are producers! http://www.naturalhistorymag.com

Decomposers Breaks down dead organisms in an ecosystem and returns nutrients to soil, water and air Bacteria and Fungi http://soils.usda.gov/sqi/concepts/soi

Cellular Respiration Burning the Fuel CELLULAR RESPIRATION is the chemical reaction that releases the energy in glucose Excess energy is stored as fat http://sps.k12.ar.us/massengale/biology 6O2 + C6H12O6 -->> 6H2O + 6CO2 + energy

Food Webs: Are interconnected food chains They show the feeding relationships in an ecosystem http://sps.k12.ar.us/massengale/biology

FOOD CHAIN – shows the transfer of energy from the sun to producer to primary consumer then to higher order consumers http://sps.k12.ar.us/massengale/biology

Food Chains Show Available Energy Trophic Levels http://sps.k12.ar.us/massengale/biology

Energy Pyramid Amount of available energy decreases for higher consumers Amount of available energy decreases down the food chain It takes a large number of producers to support a small number of primary consumers It takes a large number of primary consumers to support a small number of secondary consumers http://sps.k12.ar.us/massengale/biology

Envi Sci 1/19/11 Stamp then go over food chain/web worksheet Case Study page 130-131 Finish up notes… Tomorrow Library. Biome Project!!

The Cycling of Materials Carbon Cycle Cycled between the atmosphere, land, water and organisms Carbon is the basic building block for all living organisms It is moved through the atmosphere by plants/animals in CO2/O2 exchange through breathing and photosynthesis Large carbon deposits exist in the oceans and soil from dead organisms in the form of carbonates or carbon sinks of limestone

How Humans Affect the Carbon Cycle When we burn fossil fuels we release carbon into the atmosphere In 2000 1/3 of all carbon dioxide emitted in the US was from motor vehicles 6 Billion metric tons of carbon a year released as CO2 into the atmosphere 50% of this remains in the atmosphere which contributes to global warming 1 Billion metric tons of CO2 are dissolved into the ocean – carbon sink Plants absorb the remaining CO2

Carbon Cycle www.windows.ucar.edu/.../images/carboncycle.jpg

Nitrogen Cycle Although the atmosphere is 78% organisms cannot utilize nitrogen in that form Nitrogen Fixing Bacteria – alter the Nitrogen to make it usable for all organisms This bacteria lives on nodules of roots Nitrogen is essential for plant growth, obtained through soil Nitrogen can be found in all waste products of animals

Nitrogen Cycle www.windows.ucar.edu/.../images/nitrogencycle.jpg

Phosphorous Cycle Phosphorous is stored in rocks and soil Phosphorous is then moved through the rock and water cycle Plants and animals take in phosphorous

Phosphorous Cycle http://www.ikzm-d.de/abbildungen/59_phosphoruscycle.gif

Acid Precipitation When fuel is burned, large amounts of nitric oxide is release into the atmosphere. In the air, nitric oxide can combine with oxygen and water vapor to form nitric acid. Dissolved in rain or snow, the nitric acid falls as acid precipitation.

Fertilizers and the Nitrogen and Phosphorus Cycles Excess fertilizer causes excess nitrogen and phosphorus can cause rapid growth of algae. Excess algae can deplete an aquatic ecosystem of important nutrients such as oxygen, on which fish and other aquatic organisms depend.

Ecological succession is a gradual process of change and replacement of the types of species in a community. Primary succession is a type of succession that occurs on a surface where no ecosystem existed before Secondary succession occurs on a surface where an ecosystem has previously existed. can occur in ecosystems that have been disturbed or disrupted by humans, animals, or by natural process such as storms, floods, earthquakes, or volcanic eruptions.

A pioneer species is a species that colonizes an uninhabited area and that starts an ecological cycle in which many other species become established A climax community is the final, stable community in equilibrium with the environment.

Ecological Succession

Succession Collage Create a scenario: Primary Succession – initial growth (new volcano, island, receding sea) Secondary Succession – calamity, disaster natural or man made Cut out pictures of your area to represent each stage of succession Describe each stage and give a rationale for it

Ecological Succession Primary succession can occur on new islands created by volcanic eruptions in areas exposed when a glacier retreats any other surface that has not previously supported life Primary succession is much slower than secondary succession. This is because it begins where there is no soil. The first pioneer species to colonize bare rock will probably be bacteria and lichens, which can live without soil. The growth of lichens breaks down the rock, which with the action of water, begins to form soil.