Ecology 13.1

Pre-Assessment Which phrase best describes the focus of ecology? Individual organisms Individual cells Interactions among organisms Interactions among cells

It makes water available to the plant. 2. Which statement best describes the importance of photosynthesis? It keeps plants green. It makes water available to the plant. It provides the plant with sugar. It builds the plant DNA.

Population Community System Biome 3. Which of the following terms best describes all of the rainbow trout that live in one particular river? Population Community System Biome

4. Which of the following is an example of an abiotic factor in an ecosystem? Tree Worm Wind Bird

Gets energy by eating other resources Makes its own food 5. A cow is considered to be a consumer because it Gets energy by eating other resources Makes its own food Forms carbohydrates using chemicals Uses sunlight for energy

Ecology: The study of how organisms interact with each other and with their environment.

Ecologists study environments at different levels of organization.

Levels of Organization: Organism: any individual living thing

Levels of Organization: Population: group of the same species that lives in the same area

Levels of Organization: Community: a group of different species that live together in an area

Levels of Organization: Ecosystem: includes organisms and nonliving things such as climate, soil, water, rocks, etc.

Levels of Organization: Biome: major regional or global community of organisms characterized by the climate conditions and plant communities that thrive there.

Ecosystems 13.2

Do you remember what an ecosystem is ???

Ecosystems are made up of living and nonliving parts Ecosystems are made up of living and nonliving parts. We refer to these parts as biotic and abiotic factors.

Biotic factors are living things. plants animals fungi bacteria

Abiotic factors are nonliving things. -moisture -temperature -wind -sunlight -soil Sun Moisture

Changing one factor in an ecosystem can affect many other factors. Biodiversity: variety of life -the more biodiversity in an ecosystem, the more complex it is Keystone species: a species that has an unusually large effect on an ecosystem

Beavers are a keystone species because they create an ecosystem used by a wide variety of species creation of wetland ecosystem increased waterfowl Population increased fish population nesting sites for birds keystone species

Energy in Ecosystems 13.3

Where does the energy in an ecosystem come from?

Producers provide the energy for organisms in an ecosystem. Producers or autotrophs make their own food… …so, where do producers get their energy from??

Producers make their own food by: Photosynthesis: process where light is converted to energy in the form of glucose Chemosynthesis: the use of chemicals to make food (deep sea)

Producers provide energy for other organisms in an ecosystem Consumers get their energy from eating living or once-living resources Consumers are also called heterotrophs because they feed on many different things

Consumers are not all alike. Herbivores eat only plants. Carnivores eat only animals. Omnivores eat both plants and animals. Detritivores eat dead organic matter. Decomposers are detritivores that break down organic matter into simpler compounds. carnivore decomposer

Specialists are consumers that primarily eat one specific organism or a very small number of organisms. Generalists are consumers that have a varying diet.

Food Chains & Food Webs 13.4

Food chains and food webs model the flow of energy in an ecosystem. Food web – many food chains combined Food chain – single sequence of feeding relationships.

Trophic levels are the nourishment levels in a food chain or food web. 1st Level - Producers 2nd Level - Primary consumers are herbivores that eat producers. 3rd Level - Secondary consumers are carnivores that eat herbivores. 4th Level - Tertiary consumers are carnivores that eat secondary consumers.

Secondary Consumer Tertiary Consumer Primary Consumer *Omnivores, such as humans that eat both plants and animals, may be listed at different trophic levels in different food chains.

10% Rule Energy flows up the food chain from the lowest trophic level to the highest. Only 10% of the energy is transported from 1 trophic level to the next. Ex. producer  primary consumer 10% of the energy is transferred to the consumer while 90% is lost as heat to the atmosphere

1. For the food web, label each organism: P = producer 2= Secondary Consumer 1 = Primary Consumer 3 = Tertiary Consumer  2. Now label each animal as either a : H = herbivore C = carnivore O = omnivore

Create your own food web using a MOUSE, CORN, BLUEBIRD, KING SNAKE, HAWK, CAT, CRICKET

Pyramid Models 13.6

Pyramids model the distribution of energy and matter in an ecosystem. 3 Types of pyramids: -energy pyramid -biomass pyramid -pyramid of numbers

Energy Pyramid Shows how available energy is distributed among trophic levels in an ecosystem Outward arrows indicate energy lost as heat and waste 10% transfers to next level energy transferred energy lost

Biomass Pyramid Compares the biomass of different trophic levels within an ecosystem Biomass: measure of the total dry mass of organisms in a given area tertiary consumers secondary primary producers 75 g/m2 150g/m2 675g/m2 2000g/m2

Pyramid of Numbers Shows the number of individual organisms at each trophic level in an ecosystem tertiary consumers secondary primary producers 5 5000 500,000 5,000,000