Physiological and Biochemical Strategies of Adaptation in Halophytes.

The relationship between the ecological adaptive strategies of some halophyte groups and their metabolism has been demonstrated; this correlation determines their competitive capabilities and place in the ecosystem. The features of the content of total and membrane lipids, chlorophylls, carotenoids, and membrane and water-soluble proteins, as well as the level of lipid peroxidation, hydration of photosynthetic organs, and sodium accumulation in euhalophytes, crynohalophytes, and glycohalophytes, which are confined to different levels of soil salinity, have been established.

[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. The phenomenon of self-organization is typical for such dissipative systems; maintenance of energy flow requires the existence of complex structures that emerge spontaneously in the presence of the appropriate gradient. Critical systems, which form as a results of their activity scale-invariant structures (that are a kind of distribution channels), are optimal relative to the efficiency of substance and energy distribution. Thus, scale invariance of biological phenomena is a natural consequence of their dissipative nature.

[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". The previously revealed regularities of multifractal spectrum of the species structure of communities are shown to be true to an extent for the generic structure, as well. The second approach called "topological" one is based on an abstract representation of the results of evolutionary process in form of phylogenetic tree characterized by a non-trivial topological structure. Approbations of this approach is fulfilled by analysis of topological structure of the taxonomic tree of the class Mammalia, our calculations indicating fractal properties of its graph. These results make it reasonable to suppose that the taxic diversity, as a replica of the real diversity of the fractally organized organic world, also possesses self-similar (fractal) structure.

[Power-law species richness accumulation as manifestation of the fractal community structure].

Applications of the fractal to describing the species structure of communities are discussed. Fundamental notions of fractal geometry are explained in the first part. The problem of applying the concept of fractal to describe the spatial allocation of particular species and of community as a whole is reviewed in the second part. In the final part, the usage of the selfsimirity principle for analyzing community organization is substantiated, and evidence of the fractal structure of biocenoses is presented according to Whittaker's concept of alpha diversity. It is shown that community is characterized, as a fractal object, by scale invariance, by power function relationship between the number of structural elements of the community (individuals, populations, species) and the scale (sampling effort), and, finally, by fractional value of the power (fractal dimension). Power function is the formula the takes into account the share of rare species, or species represented by a single individual. providing for no saturation of the function f(x). This formula also does not contradict the A.P. Levich's "rule of ecological non-additivity" and, lastly, allows the application of fractal formalism to characterize the species structure of a community. It is concluded that the mathematical image of species richness is a monofractal, i.e., a set characterised by only one parameter, fractal dimension. Thus, the species structure of a community (as well as the pattern of its spatial allocation) displays self-similarity and is a fractal.

[Further study on the indices of the power of an effect]. / Eshche raz o pokazateliakh sily vliianiia.

The correlations binding the indices of influence power factor in the analysis of variance by functional dependence are given. These indices are calculated by means of Plokhinskii's, Mills-Lukomskii's and Snedekor's methods. The domains of maximum effectiveness of each index depending on the structure of variance complexes are determined. The conditions of equivalence of all indices of influence power are found.