# AN OPTIMAL SILVICULTURAL REGIME MODEL USING COMPETITIVE CO-EVOLUTIONARY GENETIC ALGORITHMS

### Oliver Chikumbo

#### Abstract

A competitive co-evolutionary genetic algorithm was successfully employed to determine an optimal silvicultural regime for the South African Pinus patula Schl. Et Cham. The solution to the silvicultural regime included: initial planting density; frequency, timing and intensity of thinnings; final crop number; and rotation length. The growth dynamics for P.patula were estimated using dynamical models, the building blocks of the combined optimal control and parameter selection formulation, with a single objective function that was maximised for value production. The results were compared against a silvicultural regime determined using Pontryagin’s Maximum Principle. Both the regimes were then compared against the recommended silvicultural regime determined from years of experimental trials. The genetic algorithms regime was superior to the other two.

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#### Paper Citation

#### in Harvard Style

Chikumbo O. (2009). **AN OPTIMAL SILVICULTURAL REGIME MODEL USING COMPETITIVE CO-EVOLUTIONARY GENETIC ALGORITHMS** . In *Proceedings of the International Joint Conference on Computational Intelligence - Volume 1: ICEC, (IJCCI 2009)* ISBN 978-989-674-014-6, pages 209-217. DOI: 10.5220/0002314202090217

#### in Bibtex Style

@conference{icec09,

author={Oliver Chikumbo},

title={AN OPTIMAL SILVICULTURAL REGIME MODEL USING COMPETITIVE CO-EVOLUTIONARY GENETIC ALGORITHMS},

booktitle={Proceedings of the International Joint Conference on Computational Intelligence - Volume 1: ICEC, (IJCCI 2009)},

year={2009},

pages={209-217},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002314202090217},

isbn={978-989-674-014-6},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the International Joint Conference on Computational Intelligence - Volume 1: ICEC, (IJCCI 2009)

TI - AN OPTIMAL SILVICULTURAL REGIME MODEL USING COMPETITIVE CO-EVOLUTIONARY GENETIC ALGORITHMS

SN - 978-989-674-014-6

AU - Chikumbo O.

PY - 2009

SP - 209

EP - 217

DO - 10.5220/0002314202090217