[Scale invariance of biosystems: from embryo to community].

Abstract-Phenomena having the property of a scale invariance (that is, maintaining invariable structure in certain range of scales) are typical for biosystems of different levels. In this review, main manifestations of the scale-invariant phenomena at different levels of biological organization (including ontogenetic aspects) are stated, and the reasons of such wide distribution of fractal structures in biology are discussed. Almost all biological systems can be described in terms of synergetics as open nonequilibrium systems that exist due to substance and energy flow passing through them.

[Multifractal analysis of the species structure of freshwater hydrobiocenoses].

The principles and methods of fractal analysis of the species structure of freshwater phytoplankton, zooplankton, and macrozoobenthos communities of plain water reservoirs and urban waterbodies are discussed. The theoretical foundation and experimental verification are provided for the authors' concept of self-similar (quasi-fractal) nature of the species structure of communities. According to this concept, the adequate mathematical image of species richness accumulation with growing sampling effort is quasi-monofractals, while the generalized geometric image of the species structure of the community is a multifractal spectrum.

[Fractal aspects of the taxic diversity].

Two approaches are suggested for describing taxic diversity as a fractal, or self-similar, object. One of them called "sampling approach" is based on necessity of taking into account the sampling process and on proceeding from the real ecological practice of exploration of the community structure. Verification of this approach is fulfilled using a multifractal analysis of the generic diversity of vascular plants of the National Park "Samarskaya Luka".