Ecosystem
•
Biotic (communities) and abiotic
(environment) components within a given area
•
Integrative
•
Process-centered (energy flow and nutrient cycles)

Solar radiation
Reflected by atmosphere
UV radiation
Most absorbed by ozone
Visible light
Absorbed by the earth
Lower Stratosphere
(ozone layer)
Troposphere
Heat
Radiated by atmosphere as heat
Heat radiated by the earth
Greenhouse effect
Fig. 3-8, p. 56

Precipitation
Oxygen (O
2
)
Carbon dioxide (CO
2
)
Water
Producer
Primary consumer
(rabbit)
Producers
Soluble mineral nutrients
Secondary consumer
(fox)
Decomposers
Fig. 3-9, p. 57

Energy Flow
•
Unidirectional movement of energy
•
Sustained directly or indirectly by photosynthesis
•
Food Chains
•
Food Webs

Ecosystem Rates of Primary Productivity
Differ
Fig. 3-16, p. 64

Food Chain
Both supported by primary production

Food Web
•
Interactions
•
Stability
•
Redundancy
•
Keystone species
Why focus on a single species?
Fig. 3-14, p. 63

Nutrient Cycling
•
Movement of nutrients through an ecosystem
•
Can return to original form; therefore, can be reused
•
Reservoirs (abiotic and biotic)
•
Fluxes (process-driven)

Nutrient Cycling – Human Impacts
•
Increase rate of removal from reservoirs
•
Constraints on processes
•
Create new fluxes

Hydrological Cycle
Fig. 3-17, p. 66

Fig. 3-18, p. 68

Biodiversity – the number and type of species, the genes they contain, and the ecosystem in which they live.
Biocomplexity – properties emerging from the interplay of behavioral, biological, chemical, physical, and social interactions that affect, sustain, or are modified by living organisms, including humans.
http://holisticbiology.stanford.edu/biocomplexity.
pdf

Ecosystem Services
– processes by which environment produces resources often taken for granted – clean water, timber, habitat, carbon sequestration. What is the ‘natural capital’?
Understanding ecological “roles” and balancing with human needs essential for developing sustainable uses

Information on Ecosystem Services http://www.esa.org/education_diversity/pdfDocs
/ecosystemservices.pdf
http://www.uvm.edu/giee/publications/Nature_P aper.pdf
http://www.ecosystemservicesproject.org/html/o verview/index.htm