What does Ecology study? Ecology Eco- oikos - house Is the study of the interactions among living things and their environment

Levels of Organization Organism – Individual living thing Population – All the members of the same species in a given area and time Community – All the different populations in the same area at a given time Ecosystem – Includes all the living and nonliving factors in a given area Biome – Major region community of organisms characterized by climatic conditions Biosphere – The area where living things can inhabit

An Ecosystem consists of all the living and non- living factors in a given area Biotic – Living things or influences from living things – Competition – PredationAbiotic – Non-living factors – Weather, humidity, sunlight, soil, sound, wind… Use the diagram above to list the factors BioticAbiotic

What is meant by Biodiversity? Biodiversity The variety of living things in an ecosystem. Highest in the rainforest Only covers 7% of earth but contains 50% of the biodiversity of species Lowest in the tundra or desert Depends on factors such as moisture and temperature.

Is there an species that has an unusually large effect on its ecosystem? Keystone species hold together an ecosystem  Beavers with their dams  Confers in the tundra  Should the keystone species disappear, there would be major changes to the ecosystem

flow of energy An ecological food pyramid shows the flow of energy in an ecosystem Consumer Heterotroph AutotrophProducer

Most of the energy is found in the producers Herbivores come next Least amount of energy in the carnivores and the top level consumers

feeding relationships A food chain is a sequence of feeding that links species by their feeding relationships. Producer 1 st Consumer 2 nd Consumer 3 rd level consumer Top consumer Plant Herbivore Carnivores ……………………………………………. Producer 1 st Consumer 2 nd Top consumer Top consumer Plant Herbivore Carnivore Carnivore

Put these organisms into a food web

And in the end, where does all the energy end up? decomposers The decomposers, which are fungus & bacteria, recycle the nutrients in dead matter and return them to the ecosystem

Is a food chain a realistic representation of food relationships in an ecosystem? What else may eat the grass, the grasshopper, the frog, or the snake? Food webs Shows the complex network of feeding relationships and the flow of energy within and sometimes, beyond the ecosystem

Examine the food web shown below. Identify the various trophic levels Producers Primary Consumers Secondary Consumers Tertiary Consumers Top Consumers

Just as the energy needs to be cycled through the living organisms in an ecosystem, so do the non-living factors such as O 2, CO 2, Water and Nitrogen Biogeochemical cycles Biogeochemical cycles move particular chemicals or elements through the biotic and abiotic parts of the ecosystem. Water Cycle Water Cycle – Cycles water through precipitation, condensation, runoff and evaporation Carbon Cycle Carbon Cycle – Cycles CO2 and O2 through photosynthesis and respiration Nitrogen Cycle Nitrogen Cycle – Cycles atmospheric nitrogen through bacteria in the soil to the plants and then to the animals

Water Cycle

Carbon Cycle

Nitrogen Cycle

What happens to all the energy as it flows through each trophic level? Is all of it transferred? Observe the energy pyramid shown below. Which trophic level will contain the most collect energy ___________________ Which will have the least amount of collective energy stored in it? _____________________

How is energy lost at each trophic level? Think of a word you learned at the start of the school year when we discussed the characteristics of all living things METABOLISM!!! – Organisms use the energy to keep it going – Moving – Digesting – Absorbing – Reproducing Most of the energy is lost as heat!!!!

Only 10% of the energy is actually transferred to the next trophic level If only 10% is transferred and 90% is lost, which organisms on this food pyramid would one be better off eating? Most of the energy is in the producers. Think of how much food the lion must eat to keep up its metabolism!!!