Presentation on theme: "Every organism requires energy to carry out life processes such as growing, moving, and reproducing. Producers: Convert light energy from sunlight to."— Presentation transcript:
Every organism requires energy to carry out life processes such as growing, moving, and reproducing. Producers: Convert light energy from sunlight to chemical energy Consumers: Obtain chemical energy from consuming other organisms Decomposers: Break down wastes and dead organisms
Food web: Pattern of feeding represented by interconnected and branching food chains.
Of the light energy that reaches plants what percentage is used for photosynthesis? 1% Biomass: Organic material manufactured by plants Primary productivity: The rate of which producers in an ecosystem build biomass. Primary productivity determines the maximum amount of energy available to all higher trophic levels.
As each consumer feeds, some energy is transferred from lower trophic levels to higher, but most energy in the preys organism’s biomass is lost.
50% of the energy in the leaf passes as the caterpillars waste. The caterpillar uses 35% of the energy from the leaf for energy for itself. Only about 15% of the leafs stored energy is turned into biomass for the caterpillar.
Energy pyramid: Shows the energy loss from one trophic level to another. An average of 10% of energy is converted to biomass in the next trophic level. 90% is lost as heat.
General steps 1. Producers incorporate chemicals from the nonliving environment into organic compounds. 2. Consumers feed on producers, either using them as energy or releasing them as waste. 3. Organisms die and decomposers break them down and return to soil.
Pyramid of numbers: Shows the number of individual organisms in each trophic level. Organized like energy pyramids.
1. Volcanoes, organisms, and cellular respiration produces carbon dioxide. 2. Plants uses the carbon dioxide and produce oxygen.
1. Bacteria convert nitrogen gas to ammonia through a process called nitrogen fixation. 2. Other bacteria take the ammonia and produce ammonium though a process called nitrification. 3. Plants absorb the ammonium and can be consumed by other organisms. Organisms die and cycle repeats.
Human activities can affect chemical cycling by moving nutrients from one place to another. Humans eat vegetables from different parts of the country. Human waste might be carried to the ocean in sewage.
What is happening to trees and forests? Deforestation: Clearing of forests for agriculture.
Burning of wood and fossil fuels is one source of carbon dioxide. As nations industrialize and use wood, carbon levels increase. What organisms use carbon dioxide to make oxygen? Plants
All the carbon dioxide builds up in the Earth’s atmosphere, trapping heat. Greenhouse effect: Natural process that stops all sun’s heat from escaping rapidly back to space.
This is leading to global warming. Global warming: Rise in Earth’s average temperature.
Who here eats fish? Why do some people not eat fish anymore? High amounts of mercury.
If a small fish has mercury in its system and gets eaten by a bigger fish… the bigger fish now has a higher amount of mercury in its system. The amount of mercury increases as the small fish gets consumed and moves up a food chain.
Pollution in the atmosphere affects a gas called ozone (O3). Ozone layer absorbs ultraviolet radiation, and shields organisms. Ozone layer is thinning because of chlorofluorocarbons. Aerosol cans, refrigerator units.
Which biome has the most biodiversity? Tropical Rainforest!
What is happening to our tropical rainforests? Deforestation
11% of the 9,040 bird species are endangered. 680 plant species of the 20,000 plant species in the US are endangered. Biologist estimate that 20% of the freshwater fish in the world have either become extinct or threatened.
The human population is increasing so we need more land for agriculture, roads etc.
Introduced species: Non-native species House sparrows, starlings came over from Europe. Compete with native birds for nesting spots. Share resources.
Overexploitation: Practice of harvesting or hunting to a degree that the number of remaining individuals may not be able to sustain the population. Ex. Rhino-Use horns for trade and medicine. Scallop- Overfished for food.
How to we maintain biodiversity and ecosystems? Balance demands for resources Establish areas than humans can not interfere with. (buffer zones) Develop natural resources.