1. 3.1 WHAT IS ECOLOGY? 3.2 ENERGY FLOW 3.3 CYCLES OF MATTER CH 3 THE BIOSPHERE

2. 3.1 What is Ecology? Ecology is the scientific study of interactions among organisms and between organisms and their environment All of these interactions around the entire planet, is considered the Biosphere

3. 3.1 What is Ecology? Species-Group of organisms so similar to one another that they can breed and produce fertile offspring Populations- groups of individuals that belong to the same species and live in the same area Community- assemblages of different populations that live together in a defined population Ecosystem-all communities together with their nonliving, or physical environment Biome- group of ecosystems that have the same climate and similar dominate communities

4. 3.1 What is Ecology?

5. Ecologists use many tools and techniques but use only 3 basic approaches Observing- Normally the first approach to ecology when scientists observe details to design further experiments and models Experimentation- Normally scientists imitate and manipulate conditions organisms would encounter in the natural world, some done within nature Modeling- Mathematical formulas based on data collected through observation and experimentation to predict future effects

6. 3.1 What is ecology? Pg 65 (1-5) Nasa’ modeling for global warming

7. 3-2 Energy Flow Sunlight is the main energy source for life on Earth Some types of organisms rely on the energy stored in inorganic chemical compounds  Autotrophs- use energy from sun or chemicals to produce food  Also known as Producers

8. 3-2 Energy Flow Using light energy to create carbohydrates is called Photosynthesis Using chemical energy to create carbohydrates is called Chemosynthesis

9. 3-2 Energy Flow Any organism that relies on another for food is considered a heterotroph or consumer  Herbivore- eats plants  Carnivore-eats animals  Detritivore- feeds on dead animals  Omnivore-eats plants and animals  Decomposer- breaks down organic matter

10. 3-2 Energy Flow Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs(consumers) This cycle is a Food Chain

11. 3-2 Energy Flow All of the food chains in an ecosystem makes up the Food web Each step in the food web is called a Trophic Level

12. 3-2 Energy Flow The amount of energy or matter in an ecosystem can be represented by an ecological pyramid Only about 10%of energy is transferred between trophic levels The total amount of living tissue within a given trophic level is called Biomass

13. 3-2 Energy Flow Pg 73 (1-4)

14. 3-3 Cycles Of Matter Unlike the one-way flow of energy, matter is recycled within and between ecosystems Passing elements, chemical compounds and other forms of matter from one organism to another are called Biogeochemical cycles

15. 3-3 Cycles Of Matter Water Cycle  Liquid is needed by all living things on Earth Evaporation is the change from liquid to water vapor Transpiration is water entering the atmosphere from living organisms

16. 3-3 Cycles Of Matter All the chemical substances that an organism needs to sustain life are its Nutrients Every living organism needs nutrients to build tissues and carry out essential life function  Like water, nutrients are passed between organisms

17. 3-3 Cycles Of Matter Nitrogen Cycle  Nitrogen Fixation-Nitrogen gas into ammonia  Denitrification- Nitrates into nitrogen gas Phosphorus Cycle  Not common in the biosphere but needed in RNA and DNA  Plants absorb it from the soil and start the cycle Carbon Cycle  Calcium carbonate needed for bones, Carbon Dioxide needed by plant to initiate photosynthesis

18. 3-3 Cycles Of Matter Primary Productivity of an ecosystem, is the rate at which organic matter is created by producers When an ecosystem is limited by a single nutrient that is scarce or cycles slowly, this substance is called a Limiting nutrient In aquatic systems and immediate increase of limiting nutrients from runoff of fertilized fields can result in quick growth called an Algal Bloom

19. 3-3 Cycles Of Matter Pg 80 (1-6)