GEOG 1HB3 Lecture Notes - Lecture 10: The Population Bomb, Paul Erlich

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blackmammoth375

22 Oct 2012

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Feedback mechanism forces which result in equilibrium conditions, i. e. , numbers of both predators and prey in keeping with the capacity of the environment. Stabilize/decrease populations: 3, thomas malthus: an essay on the principles of population , 1798. 1789 an essay on the principle of population . Malthus (1766-1834) clergyman, professor of history and political economy. World population almost 1 billion in 1798. Basic ideas underlying malthus" argument: (i) food supply increases in a linear (arithmetic) fashion (1,2,3,4,5 , (ii) population increases in a geometric exponential fashion (1,2,4,16,256, ) Influence of malthus neo-malthusians such as paul erlich ( the population. Bomb , 1968) and the club of rome ( limits to growth , 1972) If they would rather die they had better do it, and decrease the surplus population. High stationary stage: high br; high dr; total pop. Early expanding stage: high br; dr decreasing; total pop.

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

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d. a temporary decrease in plant populations