Ecosystem

• Biotic (communities) and abiotic (environment) components within a given area

• Integrative

• Process-centered (energy flow and nutrient cycles)

Fig. 3-8, p. 56

Lower Stratosphere(ozone layer)

Solarradiation

UV radiation

Visiblelight Heat radiated

by the earth

Mostabsorbedby ozone

Absorbedby the earth

Greenhouseeffect

Reflected byatmosphere Radiated by

atmosphereas heat

Heat

Troposphere

Fig. 3-9, p. 57

Decomposers

Precipitation Oxygen (O2)

Carbon dioxide (CO2)

Producer

Primaryconsumer(rabbit)

Secondaryconsumer(fox)

Producers

Water

Soluble mineralnutrients

Energy Flow

• Unidirectional movement of energy

• Sustained directly or indirectly by photosynthesis

• Food Chains• Food Webs

Fig. 3-16, p. 64

Ecosystem Rates of Primary Productivity Differ

Both supported by primary production

Food Chain

Fig. 3-14, p. 63

Food Web

•Interactions•Stability•Redundancy•Keystone species

Why focus on a single species?

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

Fig. 3-17, p. 66

Hydrological Cycle

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_Paper.pdf

http://www.ecosystemservicesproject.org/html/overview/index.htm