Биоразнообразие и его оценка. Концептуальная диверсикология - Протасов А.А.
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The concept of biodiversity is tightly related to the principle of ecological complementarity (position 1.39). Diversity serves as foundation for forming structure of systems based on complementarity of properties of a one system elements with elements properties of other. A system should consist of minimal number of elements that functionally complement each other and contain some surplus elements to provide stability and system integrity in case of stress.
Biodiversity is considered in many aspects. Different views on these multiple aspects agree on the fact that biodiversity has several levels. There are approaches connecting levels of biodiversity with levels of organization of life (position 2.3; 2.5).
However, it seems appropriate that the structure of biodiversity should have its own distinctive features. Biodiversity classification should be based on the idea by V. I. Vernadski about diversity of substance of the biosphere and emission of the living substance (position 2.8). The living substance of the biosphere has its own diversity and the main components of this diversity are the diversity of individual living substance and the diversity of species living substance. Hierarchy of the biotic diversity of associations of individuals, communities and ecosystems leads us to level of the biosphere. Thus, the structure of diversity levels is cyclic in its nature.
Biodiversity is related to the structural and functional features of communities, it increases with decrease of the overall biomass of organisms (position 3.4). It is well demonstrated on the example of biomass change due to contamination of environment: biomass usually increases at the expense of the outnumbered species (one or many), and that, in turn, leads to decrease of evenness and diversity. However, increase of biodiversity along with growth of biomass in accordance with progressive succession and growth of biomass with increase of species abundance are inconsistencies of this rule (position 3.5). The concept of the two ways display of the rule of maximum pressure of life has been suggested: in the succession process the pressure of species living substance increases, abundance of species grows and competitive relations prevent high dominance of 1—2 spe-
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Биоразнообразие и его оценка. Концептуальная диверсикология
cies. Increase of individual living substance pressure connect with to external actions, including the antropogeneous increase of the trophical level. This leads to increase of dominance of small number of species and drop in diversity. The empirical data shows that increase in diversity of communities is related to decrease in the average abundance of population (position 3.8). In more diverse communities range of indexes of abundance of certain species decreases and maximum values approach average. Diversity decreases with the increase of productivity indexes (position 3.10; 3.11). Ratio of scattered energy to the energy accumulated in biomass is an important index of the level of metabolic processes. In communities with high diversity the relative part of the scattered energy to the energy accumulated in biomass increases, (position 3.14)
Notion of ecological niche is immediately related to biodiversity problems. Niches' space separation, its numbers and volumes proportions, creates the actual diversity of communities (position 4.1; 4.3). The most essential parameters of niches' hyper-space are biotope, time and food. There is a tight connection between the species diversity and the trophic community structure (position 4.6; 4.7).
Trophic interactions in communities have significant impact on diversity (position 4.9; 4.10), as grazers and predators, consume dominating species at first and improve evenness and diversity. Thus, one of postulates about positive role of moderate disturbance for diversity is being formulated (position 5.13; 5.14). The diversity is higher in communities with species that are smaller in sizes and short-living (position 4.12). At this stage the scale correlation of organisms and elements of medium is very important, because spatial heterogeneity of environment is one of the main factors for shaping diversity (position 5.6). It is obvious, that environment is heterogeneous in different way for larger and smaller organisms. This also related to correlation between biological species time and temporal heterogeneity of a environment. Qualitative distinctions among elements of a system are not considered to be take into account for diversity evaluation (position 1.20), however, it is obvious, that various species use resource more widely or more narrowly specialized, i. e. they are closer to one of the poles of the steno- euribiotic gradient.
Excessive number of euribionts and wide niches lead to intense competitive interactions in a community. Excessive number of stenobionts might be present only in community with stable conditions. That is why communities with high diversity of species should have some optimum proportion of stenobiotic and euribiotic species (position 4.14).
