Matter and Energy in an ecosystem

1. Matter and Energy in an ecosystem Where does it all go?

2. Purpose: • Trace the flow of energy and nutrients (matter) in the living (BIOTIC) and nonliving (ABIOTIC) factors in the environment.

3. Ecology • The study of the interactions between organisms and their environment.

4. biome ecosystem community population organism organ system organ tissue Levels of Organization smallest unit of living things large region with typical plants and animals that includes several ecosystems group of different kinds of tissues working together group of organs working together all living and nonliving things interacting within a certain area all organisms of the same kind living in one area all interacting populations in an ecosystem one individual living thing group of similar cells organized to work together cell

5. Energy Flow • Energy in an ecosystem originally comes from the sun • Energy flows (moves) through an ecosystem from producers to consumers

6. Producers (aka. Autotrophs) • Use sunlight as their source of energy • Producers contain chlorophyll, a pigment that absorbs and trapslight energy • Examples: • Plants • Algae • Some bacteria, protists

7. Niche of A Producer • Niche = “job”/”role” • Captured light energy is transformed into a chemical energy that can be used by ALL organisms (PHOTOSYNTHESIS) • Other producers that do not use light; use other chemical present in the environment to produce a usable chemical energy (CHEMOSYNTHESIS) Black smoker (thermal vent) Tube worms

8. Consumers (aka.Heterotrophs) • Heterotrophs eat other organisms to obtain energy • Herbivores – eat only plants • Carnivores – eat only other animals (meat) • Omnivores – eat both plants and meat • Scavengers – eat dead, waste

9. Decomposers • By definition, are considered consumers but they are “special”….they are responsible for breaking down dead and waste to its smaller parts to put back into the soil to be reused (“recyclers”) • Examples: fungi some bacteriasome protists

10. Feeding Relationships • The purpose of many symbiotic relationships is to obtain energy and matter needed for survival. • Energy flows through an ecosystem in ONE direction • From producers to various levels of consumers

11. Models for showing energy flow • A complex model that shows many possible paths through an ecosystem is called a FOOD WEB • More realistic

12. Models for showing energy flow • Simple model that show one path through an ecosystem is called a FOOD CHAIN • ARROWS represent direction of energy flow

13. Remember… • When constructing your food chain, you must… • Start with a producer • Use ARROWS to show energy flow • Minimum of 3 links (see example below) • HOMEWORK: Create 3 food chains using the above rules.

14. Trophic levels • Each level in a food chain/web is a TROPHIC LEVEL “trophic”- feeding • Each level depends on the one before it for energy and matter

16. Ecological Pyramids • Graphic representations of the relative amounts of energy or matter at each trophic level • Include: • Pyramid of Energy • Pyramid of Biomass • Pyramid of Numbers

17. Pyramid of energy

18. Pyramid of biomass

19. Pyramid of numbers

20. Why is it a pyramid? • We stated that these were graphic representations of the relative amounts of energy or matter at each level • Large amounts of energy are lost at each link, thus only a small portion is passed to the next level • As you go up the pyramid, you find less food/energy available for use – only 10% is passed on from the previous level • We call this the “10% Rule”