jvamosi / Diversibee

Diversibee: game development for sustainability science
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Think about incorporating a bee 'carrying capacity' (max sustainable bee pop. size) for each cell #3

Closed joemudge closed 9 years ago

joemudge commented 10 years ago

The carrying capacity for a forest cell could be influenced by the number of other adjacent forest cells. Crop cells could also have very small carrying capacities so that they support a very small # of bees.

joemudge commented 10 years ago

Here's a logistic growth equation for simulating population growth/decline: popsize(t+1) = popsize(t)e^(intrinsic rate of increase(1-(popsize(t)/carrying capacity))+random variability in rate of increase)

joemudge commented 10 years ago

intrinsic rate of increase is basically how rapidly population size will grow, under ideal conditions carrying capacity is the maximum sustainable bee population size in a cell (if the population is above carrying capacity, the population will decline toward the carrying capacity, if the pop. is below carrying capacity the pop. will grow)

joemudge commented 10 years ago

each cell needs a carrying capacity for bees, with forest cells supporting many more bees than crop cells each bee species needs an intrinsic rate of increase

joemudge commented 10 years ago

To incorporate interspecific bee competition into the model, the (popsize(t)/carrying capacity) part of the model can be changed to ((popsizeA(t)+popsize(t)speciesB_ABcompeition coefficient+popsize(t)speciesC_ACcompetition coefficient)/carrying capacity) where the competition coefficients are numbers between 0 and 1, representing how closely members of other bee species represent members of bee species A, for the purposes of evaluating how closely the bee population is to the carrying capacity

joemudge commented 10 years ago

Here's an ecological modelling paper that uses the logisitic growth model with competition included. You'd need one of these evaluated for every cell. https://www.dropbox.com/s/csrgg2f72ox69z8/Kilpatrick%20%26%20Ives%202003.pdf?dl=0

abbycabs commented 10 years ago

I've implemented the carrying capcity calculations for each cell.

0 for Crop cells + 10 for each neighboring forest

1000 for Forest cells + 10 for each neighboring forest

cgmb commented 9 years ago

This more detailed model might be better suited for later levels. We plan to strip down the model complexity significantly in the early stages of the game.