Population Dynamics

Physical Quality of Life Index Map (PQL)

8-1 Population Dynamics and Carrying Capacity

8-2 Predation and the control of prey population sizes

8-3 Reproductive patterns and survival

8-4 Sustaining Wildlife populations: Conservation Biology

8-5 Human Impacts on Ecosystems: Learning from Nature

 

8-1 Population Dynamics and Carrying Capacity [tie to Garrett Hardin]

Arch

 
Population Size
  
Biotic
  Environmental
Potential
Resistance
intrinsic rate of increase
limiting factors
growth
inhibition
optimal
excessive
adaptability
maladaptive

Carrying Capacity

K - the number of individuals of a particular species that can be sustained generation after generation in a given area, space or volume of land, air, and water [LAW].

minimum viable population: the number of breeding pairs needed to sustain a constant number without compromising the genetic diversity of the gene pool.

Carrying capacity compared to assimilative capacity

Environmental Resistance - factors acting jointly to constrain populations.

Biotic Potential - capacity of any population to increase over time despite the fact that "no population can grow indefinitely due to one or more limiting factors.

What kinds of population patterns are observed in natural areas?

      1. stable
      2. irruptive
      3. irregular
      4. cyclic

     

8-2 Predation and the control of prey population sizes [link to Leopold]

Lynx and Hare populations vary in respect to one another, but how?

interaction between predator populations and the prey's food supply

8-3 Reproductive patterns and survival [Link to Colinvaux]

"They do this by trying to have as many members of the next generation as possible carry their genes."

    1. asexual
    2. sexual
      1. small egg gambit, numerous offspring
      2. large egg gambit, few offspring

       

What types of reproductive patterns do species have?Robert H. macArthur and Edward O. Wilson

r - selected species: opportunists who reproduce and disperse rapidly

K - selected species: competitors who are large, long lived with few offspring

United States population pyramid

Population pyramid

US Census Bureau

8-4 Sustaining Wildlife populations: Conservation Biology

 

Wildlife are the caged canaries in the coal mine; the alert us to dangerous changes in our surroundings

"Conservation Biology is based on Aldo Leopold's ethical principle that something is right when it tends to maintain the Earth's life support systems for us and other species, and wrong when it does not."

p.168

"beauty, integrity and diversity of the natural world"

 

8-5 Human Impacts on Ecosystems: Learning from Nature

Eight ways human interference in Land Air & Water ,LAW, diminish the quality and integrity of other life.

"We have used technology to alter much of the rest of nature in a number of ways. One is fragmenting and degrading wildlife habitats (natural areas). A second is simplifying natural ecosystems (homogenizing)."

3. diverting net primary productivity

4. inadvertent strengthening of competitors

5. predator removal or erradication

6. introduction of pests and invasive exotic species

7. overharvesting of renewable resources

8. interference with natural chemical cycles: carbon, nitrogen, phosphorus, or calcium.

p.168-169.

"The Human Footprint"

"in effect, the total ecological" impacts of human consumption and population patterns of the productive potenmtial of the Earth.

Best graphic,Figure 8-12: p, 169.

It leads us to comprehend our per capita consumption patterns have an impact on the earth.

What do we see when we reverse our view?

There are four major ways that life on earth is sustained:

      1. Solar Energy
      2. Nutrient Recycling
      3. Population Control
      4. Biodiversity

Evidence that we are at a crossroads: