1. Chapter 4: Ecosystems, Ecology, and Food Webs
Doug Friedman, Jane Beiner, Shayna Benavidez

2. Article I: Ecology & Life

3. Ecology Ecology in Greek is “house or place to live”
Study between organisms & their environment
Examining how organisms interact with their environment

4. Organisms Forms of Life which can be classified into species
5-100 million species, most are insects and microorganisms
About 1.8 million named

5. Wild & Domesticated Species
A species that lives in its natural environment (where it’s ancestors lived)
Domestic
A species that was removed from its natural environment and placed in an environment that supports the needs and wants of HUMANS

6. Some Words to Know Populations Genetic Diversity Habitat
Organisms that are part of the same species and live in the same area of space
Genetic Diversity
Each different organism has a different genetic make-up
Habitat
The place where a population lives. Each one can very in size and place.
Biological Community
A population that consists of a variety of species that live in a particular place.
Use Overhead fig 4-2

7. One more Word Ecosystem
A community of different species interacting with other species & their non-living environment
Natural or Artificial

8. LIFE! Living things are made up of one or more calls containing DNA
DNA is the instructions for making new cells and amino acids
Metabolism
Chemical reaction that capture and transform matter and energy from the environment to supply the organism

9. More LIFE Homeostasis Reproduction
Maintains optimal conditions despite changes to the environment
Reproduction
Asexual
Single cell division, or self fertilization
Sexual
Organisms exchange gametes and fertilize the ova to create offspring.

10. Article II: Earth’s Life-Support Systems

11. Layers Core Mantle Crust Fe and Trace N Solid & Liquid Fe, Si, O, Mg
Solid and Liquid
Responsible for continental drift
Crust
Fossil Fuels
Where we life

12. Spheres Lithosphere Atmosphere Bio-Ecosphere Upper mantle and crust
Thin envelope of air around the lithosphere
Bio-Ecosphere
Biotic and Abiotic Habitats

13. What is Needed to Sustain Life?
One way flow of energy
EX: Sunlight through feeding cycles, then into environment and eventually back out as infrared rays
Cycle of Matter and Nutrients
Gravity

14. Cycles Carbon Phosphorus Nitrogen Water Oxygen
CO2 from the atmosphere and earth’s water.
PHOTOSYNTHESIS
Phosphorus
DNA transfers
Nitrogen
Atmospheric N to the soil, helps with amino acids
Water
Storage, evaporation, precipitation, runoff
Oxygen

15. Open or Closed? Closed Open
ENERGY is exchanged with the environment (earth)
Open
ENERGY and MATTER is exchanged with the environment (animals)

16. The Sun Photosynthesis Earth gets 1 billionth of the sun’s energy
CO2 + H2O + sunlight  C6H12O6 + O2
Earth gets 1 billionth of the sun’s energy
28% is reflected into space
.023% gets absorbed by plants

17. Article III: Ecosystem Concepts

18. Intro Biomes Basic Zones Large Regions Characterized by features Land
Ecotone (transition)
Aquatic

19. Components of an Ecosystem
“tics”
Biotic
Living part of ecosystem
Abiotic
Non-living part of ecosystem

20. ABIOTIC Examples Air Water Nutrients Solar Energy Precipitation Wind
Altitude
Latitude
Frequency of Fire
Nature of Soil
Water Currents
Concentrations

21. Laws and Factors Limiting Factor Principle Law of Tolerance
The existence, abundance, and distribution of a species in an ecosystem are determined by whether the levels of one or more physical or chemical factors fall within the range tolerated by that species
Limiting Factor Principle
Too much or too little of any abiotic factor can prevent growth of a species

22. BIOTIC Autotrophs-Producers Heterotrophs-Consumers Photosynthesis
Chemosysthesis
Heterotrophs-Consumers
Herbivores-Primary
Carnivores-Secondary-Tertiary
Scavengers
eat already dead animals

23. Continued Decomposers Break down dead organisms into nutrients
Detritivors
eat dead animals
Bacteria
Fungi

24. GOAL OF ALL PRODUCERS & CONSUMERS
Aerobic Respiration
C6H12O6 + O2  CO2 + H2O +ENERGY

25. Article IV: Food Webs and Energy Flow in Ecosystems

26. A few Definitions Trophic Level Biomass Feeding level
Dry weight which is not counted with water because water is not a source of energy
Only small amounts of what is eaten is actually converted into biomass

27. ENERGY Some energy is lost from trophic level to trophic level
5-20% of energy is transferred from level to level
The more trophic levels the greater cumulative loss of flow (pyramid of energy flow)
The energy flow triangle shows earth could support more people if we ate grains instead of grazing animals

28. ENERGY (ct’d)
There energy loss is so large we can only support 4-5 trophic levels
Gross Primary Productivity (GPP):
The rate it takes ecosystems to convert solar energy into chemical energy as biomass
Net Primary Productivity (NPP):
It is what is left of the biomass after the organism has used parts of it to stay alive, and reproduce

29. ENERGY (ct’d) NPP is available to other organisms as food
The earth’s total NPP is the upper limit determining the planets carrying capacity for all species
Most Productivity:
Estuaries
Swamps
Marshes
Tropical Rain Forest

30. ENERGY (ct’d) Least Productive:
Open Ocean
Tundra
Desert
59% of NPP from Land, 41% of NPP from Water
Open ocean contributes a lot to NPP but phytoplankton is not reasonably harvestable
HUMANS waste 27% of potential NPP and 40% of actual

31. TATS ALL