I. Ecology and Levels of Organization in Nature

Name ______Date ______Per _____

Ecosystems

I. Ecology and levels of organization in nature

A. Organization in nature

Subatomic particles  atoms  compounds  protoplasm  cells  tissues  organs  organ systems

Organism

Population

Community

Ecosystem

Earf Planets  solar system  galaxies  universe

B. An organism’s…habitat vs range vs niche

C. Ecology--

II. Earth’s major life support systems

A. Major parts

1. atmosphere—

a. troposphere—

b. stratosphere –

2. hydrosphere—

3. lithosphere –

4. “solid” earth—crust, mantle, and core

B. The sun

5. Destiny of the sun’s energy

a. % reflected back into space

b. % heats atmosphere and earth’s surface

c. % drives the water cycle

d. % generates wind

e. % used for photosynthesis

f. All of b-e above are degraded into low quality heat = ______%

g. Greenhouse effect: GOOD

Gases such as:

interact with radiated IR radiations and release even longer wavelengths of IR energy into the troposphere

h. global warming BAD (?)

the idea of global warming is that by increasing the concentration of greenhouse gases, we…

III. Ecosystem components and tolerance

A. Biotic factors—

B. abiotic factors –

C. Tolerance limits

1. range of tolerance—range of chemical and physical conditions that must be maintained for a population to function. The existence, abundance, and distribution of a species are determined by factors being within the range of tolerance. This is called the

2. Tolerance limit

3. limiting factor/limiting factor principle: even if everything else is within the range of tolerance, ….

D. Food Makers and Food takers

1. Organisms that produce their own food are called:

a. examples:

b. how?

2. Organisms that feed on other organisms are called:

a. organisms that eat plants:

b. organisms that eat meat:

c. organisms that eat both:

d. organisms that eat detritus (dead leaves/wood, parts of dead organisms, waste, etc. YUM!):

1. detritus feeders

2. decomposers

E. What fuels life’s processes: everybody’s doing it! =

F. Biodiversity

1. variety of genes in a population 2. variety of species present 3. variety of roles (niches) in an ecosystem

IV. Energy flow in ecosystems

A. Food chains and food webs

1. food chain—

2. trophic levels

3. food web

B. Representing energy flow: Energy pyramids

The dry weight of all organic matter contained in organisms on a certain trophic level is called ______. The percentage of usable energy transferred as biomass from one trophic level to the next is called ______. It averages ______%. The other ______% is lost as low quality ______. This explains 3 things: 4

V. Primary productivity in ecosystems

A. Gross primary productivity—

Look at Fig. 4-22. Where are areas of GPP highest and lowest on land and at sea?

B. Net 1o productivity: NPP = GPP- R

In Fig. 4-24, what are the top 3 and bottom 3 terrestrial ecosystems in terms of avg NPP?

What is the top and bottom aquatic ecosystem in terms of avg NPP?

What is the unit used for avg NPP?

Another figure not in the current edition of your textbook reveals that the open ocean is highest in terms of total GPP but Fig 4-24 indicates that its avg NPP is pretty low. Why do you think this is so?

VI. Soil

A. What is it?

Thin covering over most land that is a complex mixture of 5 things:

B. Why is it important?

C. Soil Horizons—horizontal layers of varying composition and texture: A cross section of these layers is called a soil profile.

1. O horizon/surface litter layer

2. A horizon/topsoil

3. B horizon/ subsoil

4. C horizon/parent material

5. bedrock 5

D. Infiltration/percolation and Leaching

E. Texture and things that result from it

1. texture—determined by the size of the particles that make up a soil

a. clay

b. silt

c. sand

d. loam

2. porosity—volume of spaces per volume of soil

3. workability: how easy it is to use your hoe

4. permeability

5. water/nutrient holding capacity

6. comparison:

VII. Nutrient cycles (biogeochemical cycles)

A. Hydrologic (water) cycle

1. Importance of water in life: everything takes place in it

2. Main processes definition from/to

a. evaporation

b. transpiration

c. condensation air to air

What are condensation nuclei?

d. precipitation

e. percolation

f. runoff

3. What two processes power the water cycle? 6

4. Roles of the water cycle

a. replenish…

b. shape the landscape through what process? c. Water dissolves many substances, which enables the water cycle to do what two things?

d. How is water purified in the hydrologic cycle? (2 ways)

5. Human impact on the water cycle

a. withdraw too much (overdraft)  (2 things)

b. remove vegetation and replace with asphalt  (4 things)

c. modify water quality by…

B. The carbon cycle

1. What is the importance/ role of carbon in life?

2. Processes

a. What is the concentration of carbon dioxide in the troposphere?

b. Where else is it found?

c. What four processes add carbon dioxide to the troposphere?

d. How is carbon dioxide removed from the troposphere? Who carries this process out? 7

e. What are two ways the carbon trapped in fossil fuels can be released into the troposphere?

2. f. How does carbon dioxide get into the ocean?

g. How is carbon dioxide released into the troposphere from the ocean? What role does temperature play in this process?

3. Human impact on the carbon cycle

a. vegetation removal: less CO2 absorption and decay produces CO2

b. burning fossil fuels: CxHy + O2  CO2 + H2O

C. The nitrogen cycle 1. Importance/role of nitrogen in life

2. Major processes Definition (include who does it and where it goes from whence it came)

Nitrogen fixation

Nitrification

Assimilation

Ammonification

Denitrification

3. Human impact on the nitrogen cycle

a. When we burn any fuel, what do we add to the atmosphere and what does it become and what does that do?

b. What is made from bacterial action on livestock waste and inorganic fertilizer and what TWO negative environmental impacts does it have?

c. What is released when forests, wetlands, and grasslands are destroyed?

d. Addition of excess nitrates come from what two sources? What type of ecosystem do they disrupt? 8

e. How can nitrogen be removed from topsoil?

f. How have we shifted biodiversity as it pertains to the nitrogen cycle? D. The phosphorus cycle 1. Processes a. What phase of matter does the phosphorus cycle NOT have?

b. Is the phosphorus cycle fast or slow?

c. How is phosphorus typically found in nature?

d. How is the phosphorus released?

e. How do animals get phosphorus?

f. How do plants get phosphorus?

g. Why is phosphorus often a limiting factor to terrestrial plants?

h. What is guano?

2. Human impact on the phosphorus cycle a. Why do we mine for P?

b. What happens to soil P when we chop down tropical rain forests?

c. Addition of excess phosphorus comes from what two sources? What type of ecosystem do they disrupt? This should sound familiar!

E. The Sulfur cycle 1. Processes

a. Where is most of earth’s sulfur?

b. What is H2S?

Natural sources:

Human sources:

c. What is SO2?

Natural sources:

Human sources:

d. How do particles of sulfate salts get into the atmosphere? How do plants get them?

e. Who produces DMS? What is the role of DMS in weather? 9

f. What environmental problem do SO2 and sulfate salts cause? HOW?

2. Human impact on the sulfur cycle: What are the THREE ways that humans add sulfur dioxide to the atmosphere?