What is Ecology?

1. What is Ecology? • The scientific study of interactions among organisms (biotic) and between organisms and their environment (abiotic).

2. Levels of Organization Ecologist study organisms ranging from the various levels of organization: Species Population Community Ecosystem Biome Biosphere

3. Levels of Organization Species- organisms that are similar enough that they can breed together and produce fertile offspring Population- all members of the same species that live in an area Community- all the populations that live in an area Ecosystem- all of the living and non-living parts of an area Biome- group of ecosystems with similar climate and dominant communities (living things) Biosphere- all areas of earth where life exists

4. 3-2 Energy Flow A. Producers 1. Energy From the Sun 2. Life Without Light B. Consumers C. Feeding Relationships 1. Food Chains 2. Food Webs 3. Trophic Levels

5. Autotroph Auto- = self -troph = food Makes its own food for energy aka PRODUCER Heterotroph Hetero- = different -troph = food Has to eat to get energy aka CONSUMER Autotrophs vs. Heterotrophs

6. Photosynthesis: the transformation of light energy into stored chemical energy in the form of sugars Sunlight is the main source of energy for life on earth. 6 CO2 + 6 H2O + light energy C6H12O6 + 6 O2

7. Chemosynthesis Some living things use chemicals for energy. Chemoautotrophs CO2 + 4H2S + O2 CH2O + 4S + 3H2O

8. Herbi – Carni – Omni – Detriti– -vore Plant Meat Everything/All Waste (detritus) eater Types of Consumers Herbivore Carnivore Omnivore Detritivore

9. 3–2 Energy Flow C. Feeding Relationships Food Chains Food Webs: interconnected food chains Trophic Levels: decomposers primary producers primary consumers: herbivores secondary consumers: carnivores tertiary consumers: top-level carnivores

10. How Does Energy FLOW Through an Ecosystem? • In ONE direction! • Sun or chemicals • Autotrophs • Heterotrophs IT DOES NOT GET RECYCLED!

11. Feeding Relationships Food Chain a series of steps in which organisms transfer energy by eating or being eaten (only one organism at each trophic level) Food Web network of all the food chains in an ecosystem Trophic Level each step in a food chain or food web

12. Trophic Levels • Primary producer (aka producer) • Primary consumer • Secondary consumer • Tertiary consumer • And so on… (High Level Consumers)

13. Ecological Pyramids • Trophic Level – each step in a food chain or food web Biomass Pyramid Energy Pyramid Pyramid of Numbers

14. Pyramid of Energy – amount of energy available at each trophic level Most of the energy (90%) is used by an organism for life processes and/or lost as heat Only 10% of the energy from each trophic level is passed on to the next level

15. How doesMatter move through an ecosystem? • Unlike the one way flow of energy, matter is recycled within & between ecosystems • Nutrients are passed between organisms & the environment through biogeochemical cycles • Biogeochemical Cycles: • Bio –life • Geo – Earth • Chemo – chemical

16. Nutrient Cycles • Every living organism needs nutrients to build tissues and carry out essential life functions. 95% of your body is made of… • OXYGEN • CARBON • HYDROGEN • NITROGEN

17. CO2 • What processes result in carbon entering plants and animals? • How does carbon return to the atmosphere as CO2? • How do humans impact the C-cycle? CO2

18. Carbon Cycle 4 PROCESSES move carbon through its cycle: • Biological- photosynthesis, cellular respiration, decomposition • Geochemical- erosion, volcanic activity • Mixed biochemical- formation of fossibl ffuels from deposition of dead organisms and pressure over time • Human Activity- burning fossil fuels, mining, cutting and burning wood

19. Nitrogen Cycle (Figure 3-14) N2 in Atmosphere N03- & N02- NH3 • Nitrogen-containing nutrients in the biosphere include: • Ammonia (NH3) • Nitrate (NO3-) • Nitrite (NO2-) ORGANISMS NEED NITROGEN TO MAKE AMINO ACIDS FOR BUILDING PROTEINS!!!

20. With a partnerfigure 3-14 N2 in Atmosphere • What processes result in Nitrogen returning to soil as NH3? • How does Nitrogen return to the atmosphere as N2? • How do humans impact the N-cycle? N03- & N02- NH3

21. Nitrogen Cycle N2 in Atmosphere N03- & N02- NH3 • Nitrogen fixation: • certain bacteria use atmospheric N2 and create NH3(the only organisms who can use N2 directly.) • Denitrification: • other bacteria convert nitrogen compounds back into N2.

22. Phosphorous Cycle Phosphorous forms part of important life-sustaining molecules (DNA & RNA, ATP)

23. Water Cycle

24. Limiting Nutrients • Substances in such short supply that they limit the growth of organisms in an ecosystem. • Often scarce or cycle slowly • In marine ecosystems, often N

25. Algal Bloom • Occurs when a limiting nutrient is added to an ecosystem, resulting in an immediate increase in the amount of algae or other producers • P and N • Can upset the health of an ecosystem • More producers, more biomass for decomposers to break down, use up O2, fish die • HABs- neurotoxins produced

26. Niche • All aspects of an organisms existence that enable it to survive and reproduce in its environment; its “role” in the ecosystem • IT IS NOT the habitat (where it lives) only! • Includes • Energy source (ex. food) • Trophic level (what it eats, what eats it) • Temporal and spatial scales (timing of feeding, mating, etc; where it feeds, lives, etc.)

27. The Niche- the role an organism plays in its ecosystem Cape May Warbler Feeds at the tips of branches near the top of the tree Bay-Breasted Warbler Feeds in the middle part of the tree Yellow-Rumped Warbler Feeds in the lower part of the tree and at the bases of the middle branches Spruce tree

28. Competitive Exclusion Principle • No two species can occupy the same niche at the same time in the same space. • One species will outcompete the other, resulting in either • Extinction of the other species • Speciation (species adapts to fill different niche)