Some Patterns of Spatial-Ontogenetic Structure in Populations of Tuber Orchids
M. B. FARDEEVA
Kazan Federal University, 420008, Kazan, Kremlevskaya str., 18
Keywords: пространственно-онтогенетическая структура, микролокусы, агрегации, дискретный и дискретно-континуальный типы, Spatial-ontogenetic structure, microloci, aggregations, discrete and discrete-continuous types
Abstract
Population dynamics, density and aggregation size of tuberoid orchids were identified based on mapping, electronic maps construction with application of “point processes”, Ripley function and pair-correlation function. Discrete and discrete-continuous types of spatial structure dominate in populations in optimal ecological conditions. Bounded aggregations of levels I (radius 0,45-0,75 m) and II (radius 1,2-2,5 m) are formed at 3 to 7,5 m. Spatial pattern depends on generative specimens which are related with “group effect”. The microloci have full ontogenetic structure and may be regarded as elemental populations. They form larger aggregations of levels III and IV with random spatial distribution and continuous bounds. Aggregations of higher level are not formed in worse ecological conditions. Random spatial distribution and incomplete ontogenetic spectrum of microloci are indicators of critical population status.
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