Introduction to Ecology

What is Ecology?  Study of organism interactions with other organisms and the environment

3 Habitat & Niche  Habitat is the place a plant or animal lives  Niche is an organism’s total way of life

What shapes an Ecosystem?  Biotic factors: all living organisms within an ecosystem  ie – animals, fungus, plants, bacteria  Abiotic factors: physical and non-living factors within an ecosystem  ie – soil type, sunlight, temperature, precipitation

5 What are the Simplest Levels?  Atom  Molecule  Organelle  Cell  Tissue  Organ  System

Levels of Organization  Species  Population  Community  Ecosystem  Biome  Biosphere

7 1 st Level of Organization  Organism: An individual living thing that is made of cells, uses energy, reproduces, responds, grows, and develops  Ex: 1 zebra

Population  Groups of the same species that live in one particular area  Ex: all elephants that live in the African savanna

Community  Groups of different populations that live in a particular area.  Ex. All living things found in the African savanna such as elephants, giraffes, lions, grasses, trees, etc

Ecosystem  All living AND non-living components to a particular area  Ex. All the animals of the African savanna plus the climate such as temperature, precipitation and soil type

Biome  Group of ecosystems that have the same climate and communities  Ex: Savanna

12 6 th Level of Organization  Biosphere: The portion of Earth that supports life.

13 What level of Organization? Species/Population

14 Energy Flow Through an Ecosystem Food Chains, Food Webs, Energy Pyramids

Energy Flow  Main source of Energy – SUN  Autotrophs/Producers – use sunlight or chemicals to produce organic compounds 6CO 2 + 6H 2 O + sunlight  C 6 H 12 O 6 + 6O 2

16 The energy that is not used by producers can be passed on to organisms that cannot make their own food.

17 Heterotrophs/consumers – must take in organic compounds in order to make energy  Primary Consumers or Herbivores – only eat plants  Secondary Consumers or Carnivores – only eat animals  Tertiary/Quartenary Consumers or Omnivores – eat both plants and animals  Detritivores – eat dead material  Decomposers – break down organic matter

Trophic Levels  Shows the amount of energy contained at each level  Three types:  Energy pyramids  Biomass pyramids  Pyramids of numbers

Energy Pyramids  Organisms need energy  They get energy from food  Use energy in respiration, movement, reproduction  Only 10% of energy is passed from one trophic level to the next

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Energy Pyramids

22 Energy Pyramids Show  Amount of available energy decreases down the food chain  It takes a large number of producers to support a small number of primary consumers

Biomass Pyramid  Biomass – total amount of living tissue within a trophic level  Grams of organic matter/unit area  Shows amount of potential food

Biomass Pyramid

25 Food Chains Show Available Energy

Pyramid of Numbers  Shows the number of individual organisms in each trophic level

27 The transfer of energy from the sun to producer to primary consumer then to higher order consumers can be shown in a FOOD CHAIN.

28 Food Webs:  Are interconnected food chains  They show the feeding relationships in an ecosystem

29 Identify the Producers, Consumers, & Decomposers: Count the Food Chains!