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Openaq Pulse Saltmrsh Prairie Fire Lagoon Climax Species Specarea

Climax and Succession

Description:

This is a model of ecological succession leading to a climax ecosystem. It starts on a bare field with a few grasses and ends with larger plants like trees. The growth of biomass depends on renewable outside energy sources, but also on the diversity. As the quantity of biomass increases, it provides niches for seeding from outside to increase the diversity. The greater the diversity the more productivity.

Examples:

  • The climax species in the grasslands biome are grasses, in the coral reefs they are corals
  • human civilisations and businesses
    		•  Diagram

    Variables:

    I = energy sources (rain, sun, wind)
    S = seeding
    B = biomass
    D = diversity
    PG = gross production
    DB = net production
    K4 = harvest

    Equations:

    R = I/(1 + K0*D + K1*B)
    PG = K2*R*D + K3*R*B
    DB = PG - K5*D*D - K6*B - K4*B
    DD = K8*B*S - K9*D - K7*D*D

    Simulation:

    The graph shows the changes of d (blue), b (green), pg (orange), db (pink) over the period of succession until climax.
    Source code: Climax.java

    "What if" Experiments:

    Think about a rain forest.

  • If growth occurs without seeding species, what will happen to the quantity of biomass?
  • If you increase thew harvest (yield) 20 times, what happens to the biomass and to diversity?
  • What would happen to the system if there were a climate change which reduced the rain in half?
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