index Expo Renew Nonrenew 2source Slowren Factors Recycle Daypr

Growth on a Nonrenewable Source

Description:

A nonrenewable source is a storage, a limited quantity. A population living of a nonrenewable source first increases exponentially while their source decreases. As soon as the source is used up, the population decreases too.

Examples:

  • A mining town living on a limited source of gold ore
  • A person given an inheritance: He uses the money for going on trips. As the money runs out, his trips decrease and then cease.
    		•  Diagram

    Variables:

    E = nonrenewable energy source
    K = decreasing factor of E
    K1 = increasing factor of Q
    K4 = decreasing factor of Q

    Equations:

    DE = -K*E*Q
    DQ = K1*E*Q-K4*Q

    Simulation:

    The graph shows the changes of E (blue) and Q (red) over a time period.
    Source code: Nonrenew.java

    "What if" Experiments:

    Think about a population of beetle that grow of a limited quantity of dead wood:

  • What would happen if the tree which fell in the storm was a bigger one?
  • What would happen if you started with 100 times more beetles?
  • Try a different species of beetles which have a more efficient growth rate.
    		•