Article:
Fischlin, A. & Baltensweiler, W., 1979. Systems analysis of the larch bud
moth system. Part I: the larch-larch bud moth relationship. Mitt.
Schweiz. Ent. Ges., 52: 273-289.
Abstract:
Cyclic fluctuations in the abundance of the larch bud moth, Z. diniana Gn. (Lep. Tortricidae) were studied in a program which treats the various hypotheses by means of systems analysis. Based on data from the laboratory and the Upper Engadine valley of Switzerland, the hypothesis proposing that the gradation cycles are caused by interaction between the host plant larch and the insect larch bud moth was modeled. In simulation studies the model's behavior was similar to that of the real system. Sensitivity analysis revealed this behavior to be sensitive to the recovery rate of the trees after defoliation. On this recovery process only scanty field data are available. Despite consistence of simulation results and observations, the hypothetical model can not be accepted nor rejected definitively. Because of a cycle of the system lasts about 9 yr, it is not possible to gather the needed measurements on the raw fiber content of the larch needles. By modeling all the hypotheses plus comparing the respective models, a basis is provided to decide unequivocally which hypothesis best explains the real larch bud moth system.