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Untersuchungen zur Verbesserung der Wirksamkeit von phosphororganischen Insektiziden durch Mittel zur Steuerung biologischer Prozesse
Authors:Dr. Siegfried Richter  Dr. Fernando Caceda
Affiliation:Karl-.Marx-Universlt?t Leipzig Institut für tropische Landwirtschaft ,
Abstract:From the position of trophical niche concept, the process of forming of an infestation spot of the winter pine shoot moth in a space of a pine stand as well as the process of degradation of this spot was studied.

It was shown that the process begins with the emergance of separate microspots in a stand. With increasing age of the affected stand, the area of these microspots grows, and they unite themselves in lager ones together with growing pest density. The process of growth of both the area and the density continues to an age of 15 years of the pine stands. After that, the reverse process of degradation begins when the area and density decreases. On all the stages of the process, a distribution of density of the pest attacks on trees has contagious character, and stabilisation of an affected ecosystem is finished at the age of 20–30 years.
Keywords:Trophical niche  winter pine shoot moth  pine  population dynamics of insects in space
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