GGR107H1 Lecture Notes - The Population Bomb, Disconnection, Carrying Capacity

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coralcrab547

29 Jan 2012

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Document Summary

Need to search for food, food varies depending on season, limited supply, population can"t maintain population growth. Limits potential for population growth, won"t reproduce on a basis simple social structure constant. Consequences -> settled population, population growth, social organizations. Development of writing, math, laws, etc. by the agricultural revolution. Problems controlling disease - facing problems of famine, no way to control pests. Increase level of manipulation of food supply -> genetic done slower than today (less accurate) Increase diversity of food -> healthier population. Introduce machinery into agriculture -> increased food production -> began the can do more than humans -> industrial revolution. Increasing level of production, more goods produced. Increase food availability -> linking markets and sources of food. Economics lead the way -> transition from agricultural society to industrial society. Families get smaller less help needed on the farm. *crude birth rates (cbr) -> per 1000 of population. *crude death rates (cdr) -> per 1000 of population.

Related Questions

The fish population P(t) in a lake is suddenly attacked by adisease that render the fish unable to reproduce. Assuming that thedeath rate of the fish is inversely proportional to the square rootof the fish population (i.e. k1 = Î²/â(P) where Î² is aconstant), perform the following tasks:

1. Write a differential equation that models the population offish as a function of time. Assume that the fish are infected bythe disease at t = 0 and define your constants.

2. Solve the differential equation with the initial condition thatP(0) = P0.

3. What is the half-life of the fish population?

4. If there were 900 fish initially, and 441 are left after 6weeks, how long does it take for all the fish to die? Assume thatthe disease was caused by radioactive waste dumped in the lake. Itis discovered that another population of fish, S(t), spontaneouslymutate into the original fish at a rate of k2 (per week) and neverdie. The population S(t) are born at a rate k3.

5. Draw a diagram that describes the life cycle of these twofish populations including your rate constants.

6. Write the differential equations describing the populationsof P(t) and S(t).

What is the most likely consequence of open pit mining on plant life?

a. a dramatic reduction in the variety of plant species

b. an increase in the number of plant species

c. the complete loss of plant life in the area occupied by the surface mine

d. a temporary decrease in plant populations