I. Ecology A. the study of the interactions organisms have with each other and with their environment.

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1 I. Ecology A. the study of the interactions organisms have with each other and with their environment. B. word ecology by Earnst Haeckel in 1866 from the Greek oikos meaning house economy C. Interactions happen in the biosphere a. Thin layer of Earth where life exists (5 mi below ocean to 3.5 mi above surface) b. Divided into 3 regions: 1. Lithosphere-land (rocks, sand, soil) 2. hydrosphere-water (oceans, lakes, rivers, clouds, underground) 3. atmosphere-layer of air surrounding Earth

2 II. Levels of organization in the biosphere (species population community ecosystem biome biosphere) A. Species 1. organisms that look alike and can reproduce 2. live in a specific environment called a habitat 3. biodiversity the variety of species in an ecosystem B. Population - group of the same species living in the same place at the same time C. Community - all of the populations living in an area D. Ecosystem - all of the communities in an area plus the abiotic factors of the environment. 1. biotic factors living things in an ecosystem 2. abiotic factors nonliving things in an ecosystem Ex) temperature, rainfall, nutrients, etc E. Biome very large area with unique ecosystem because of unique climate (temperature & precipitation)

3 III. Population Interactions A. The maximum number of organisms that an area can support is called the ecosystem s carrying capacity Carrying Capacity ~80 Deer B. The carrying capacity is determined by limiting factors 1. Density-Dependent Limiting Factors Things that affect large, dense populations more than smaller, less dense populations. Ex: food, space, disease 2. Density-Independent Limiting Factors Things that affect populations regardless of their size or density. Ex: floods, fire, drought

4 C. Limiting factors cause populations to interact in several ways: 1. territories - establishment of own area 2. predator/prey-one organism kills another 3. symbiosis - two organism living closely a. parasitism-one organism feeds off another without killing it (one benefits, one is harmed) b. mutualism-both organisms benefit

5 c. commensalism-one organism benefits, other is unaffected

6 V. Ecosystems 1. each organism in an ecosystem has a specific niche a. the role/job of an organism in an ecosystem. b. how it deals with the biotic and abiotic forces in its habitat. c. what it eats, what it feeds, where it lives, how it reproduces, etc. 2. Ecosystem are all about energy flow a. all energy on Earth originates from the sun b. an ecosystem is made of many trophic levels Step in Food Chain Name of Trophic Level How it Feeds Other Terms to Describe this Trophic Level 1 st producer Autotroph (energy from sun) Plants 2nd Primary Consumer Heterotroph (eats P s) Herbivores 3 rd Secondary Consumer Heterotroph (eats PC s) Carnivores Organisms that are PC s + any other 4th Tertiary Consumer Heterotroph (eats SC s) Carnivores Consumer are Omnivores 5th Quaternary Consumer Heterotroph (eats TC s) Carnivores Final Decomposers Heterotroph (eats dead things) Fungi & Bacteria Return the stored energy & nutrients back to the PC s

7 c. several ways to show energy flow in an ecosystem: 1) food chains=simple order of who-eats-who *overly simplified *unstable 2) food pyramids=show how the energy in each trophic level decreases. *10% Rule only 10% of the energy passes along to the next trophic level. Tertiary Consumers (Heterotrophs) Secondary Consumers (Heterotrophs) Primary Consumers (Heterotrophs) Producers (Autotrophs)

8 3) Food webs=network of food chains showing all feeding relationships in an ecosystem. *more realistic than a food chain *show ecosystem stability

9 d. Not only energy flows through an ecosystem. Pollution also gets passed along from one level to the next and gets stronger as it collects in the organism at the top of the food chain. This process is called biological magnification or bioaccumulation. Examples of Bioaccumulation: 1. DDT - bald eagles nearly went extinct because the fish it ate had eaten bugs killed by DDT pesticides. The eagles eggs had shells that were too thin to survive because of the pollution passed along the food chain.

10 2. PCB s-chemical used to make electrical insulators and wood sealants -carcinogenic -build up in fat 3. Heavy metals *lead-from batteries, old paint, water pipes -birth defects, brain damage - Mad Hatter s disease (tremors, nerve damage, insanity) -build up in fish fat *mercury-from mines and paper mills -brain damage, deformities -also builds up in fish fat

11 VI. Natural Ecosystem Change A. most ecosystems change over time in a predictable sequence called ecological succession. B. Communities and niches appear and disappear. C. Steps in land succession: 1. pioneer species -the first organisms to colonize bare rock -mosses, insects, lichens secrete enzymes that break rock into sand *weathering and lichens turn rock into soil

12 2. Intermediate Species grasses and shrubs - build soil more fast-growing trees 3. Climax community (oak and maple trees) -not replaced by another community unless the area is disturbed by fire, flood, logging, etc.

13 Different areas of the world have different abiotic factors (temperatures, rainfall, etc.) so they develop different climax communities. An area with a unique climax community is called a biome. Ex) rain forest, desert, tundra, savanna, etc. D. Primary vs. Secondary Succession

14 E. Steps in Lake Succession: 1. Oligotrophic lake -clear, cold water with lots of oxygen -sandy bottom without weeds -few nutrients -salmon, trout -Lake Michigan 2. Mesotrophic lake -starting to fill in with debris -warmer, murkier, weeds, lower oxygen -bass, bluegill -Muskegon Lake 3. Eutrophic lake -very much filled in with debris -warm, muddy, shallow, no oxygen -frogs, snakes, carp -Muskegon Marsh *people speed up the eutrophication (aging) of lakes by putting excess nutrients into the water from lawn fertilizers and sewage.

15 VII. Ecosystem Disruption A. Each part of an ecosystem is necessary and interdependent B. Several things can cause an ecosystem to become unstable and potentially collapse: 1. Stochastic Events natural disruptions such as storms and earthquakes 2. Removal of a Species The Lesson of the Kaibab

16 3. Pollution the wrong substances in the wrong place in the wrong quantity a. point-source pollution=from a single identifiable place (factories, dumps, etc) b. nonpoint-source pollution=from many places (parking lot runoff, lawn fertilizers, etc)

17 4. Habitat Fragmentation breaking one large area into several small areas. a. interrupts territories b. interrupts migrations c. increases edge area

18 5. Invasive Species nonnative organisms that disrupt established ecosystem energy flow. Examples of Invasive Species of the Great Lakes: Zebra Mussels & Quagga Mussels

19 Sea Lamprey So, how d they get here???

20 Emerald Ash Borer Eurasian Watermilfoil & Curly-Leaf Pondweed Round Goby

21 And the famous Asian Carp Management plans for invasive species typically involve 4 steps: 1. Prevention How are we trying to keep it from spreading to other areas? 2. Detection How do we know that it is in an ecosystem? 3. Control & Management How are we trying to get rid of it? 4. Restoration & Rehabilitation of the Ecosystem How are we trying to fix an ecosystem once the invasive population is reduced or eliminated?

22 VIII. Cycles of Matter A. Water Cycle

23 B. Carbon Cycle

24 IX. Fossil Fuels carbon from the remains of organisms that lived long ago. A. Types of Fossil Fuels: 1. Coal-compacted plant remains from ancient swamps. -burned to heat water to spin turbines to make electricity. 2. Petroleum-liquid formed from remains of microorganisms in ancient seas. -made into gasoline, grease, oil, plastics 3. Natural Gas-gas formed along with petroleum -cleaner burning B. Problems with fossil fuels 1. nonrenewable-can t make more 2. hazardous to extract & transport 3. puts carbon (CO 2 ) into atmosphere that is supposed to be locked up underground. X. Our Atmosphere A. Greenhouse Effect-natural process of Earth s atmosphere trapping sun s energy to keep warm. B. PROBLEM: burning fossil fuels thickens the CO 2 layer around Earth and too much heat is trapped in, resulting in Global Warming.