Introduction

The diversity of life has long been a subject of study. The first systems of living nature, known, for example, from the works of Aristotle (384-322 BC), already relate to the analysis of this phenomenon. The scientific and methodological basis for describing biodiversity was created by K. Liney in his “System of Nature”. And in the future there was an accumulation of knowledge.

And in the last decade, the term “biodiversity” has become extremely popular. Since the signing of the Convention on Biological Diversity by many states in 1992, this word has constantly been heard in government decrees, documents of state and public organizations, in media mass media. Scientific research proved that a necessary condition The normal functioning of ecosystems and the biosphere as a whole is a sufficient level of natural diversity on our planet. Currently, biological diversity is considered as the main parameter characterizing the state of supraorganismal systems. In a number of countries, it is the characteristics of biological diversity that serve as the basis for the environmental policy of the state, seeking to preserve its biological resources in order to ensure sustainable economic development.

Biodiversity conservation is discussed at the global, national, and regional levels. However, the meaning of this word is not understood correctly by everyone. Why is biodiversity given such attention, what role does it play in the lives of people and the planet, how is it changing, what threatens it and what needs to be done to preserve it - my work is devoted to answering these questions.

The purpose of the work was to study methods and assessments of biodiversity

During the work, the following tasks were set:

1) consider the concept of “biodiversity”;

2) identify features of biodiversity;

3) study methods and assessments of biodiversity.

The object of the study was biological diversity as the diversity of natural ecosystems on the globe.

The subject of study was the current state of biological diversity.

biological environmental policy

Biological diversity

Biodiversity concept

The phrase “biological diversity”, as noted by N.V. Lebedev and D.A. Krivolutsky, first used by G. Bates in 1892 in famous work"A naturalist in the Amazon" when he described his experiences encountering seven hundred species of butterflies during an hour-long excursion. The term “biodiversity” came into wide scientific use in 1972 after the Stockholm UN Conference on the Environment, when ecologists managed to convince the political leaders of the world community that the protection of wildlife is a priority task for any country.

Biological diversity is the totality of all biological species and biotic communities formed and emerging in different habitats (terrestrial, soil, marine, freshwater). This is the basis for maintaining the life-supporting functions of the biosphere and human existence. National and global problems of biodiversity conservation cannot be implemented without fundamental research in this area. Russia, with its vast territory, which preserves the main diversity of ecosystems and species diversity of Northern Eurasia, needs the development of special research aimed at inventorying, assessing the state of biodiversity, developing a system for its monitoring, as well as developing principles and methods for the conservation of natural biosystems.

According to the definition given by the World Wildlife Fund, biodiversity is “the entire diversity of life forms on earth, the millions of species of plants, animals, microorganisms with their sets of genes and the complex ecosystems that make up living nature.” With such a broad understanding of biodiversity, it is advisable to structure it in accordance with the levels of organization of living matter: population, species, community (a set of organisms of one taxonomic group in homogeneous conditions), biocenosis (a set of communities; biocenosis and environmental conditions are an ecosystem), territorial units of a larger rank - landscape, region, biosphere.

The biological diversity of the biosphere includes the diversity of all species of living beings inhabiting the biosphere, the diversity of genes that form the gene pool of any population of each species, as well as the diversity of biosphere ecosystems in different natural zones. The amazing diversity of life on Earth is not just the result of the adaptation of each species to specific environmental conditions, but also the most important mechanism for ensuring the sustainability of the biosphere. Only a few species in an ecosystem have significant numbers, biomass and productivity. Such species are called dominant. Rare or scarce species have low numbers and biomass. As a rule, dominant species are responsible for the main flow of energy and are the main environment-formers, strongly influencing the living conditions of other species. Small species form a kind of reserve and when various external conditions change, they can become part of the dominant species or take their place. Rare species mainly create species diversity. When characterizing diversity, indicators such as species richness and evenness of distribution of individuals are taken into account. Species richness is expressed as the ratio of the total number of species to the total number of individuals or per unit area. For example, under equal conditions, two communities are inhabited by 100 individuals. But in the first, these 100 individuals are distributed among ten species, and in the second, among three species. In the example given, the first community has richer species diversity than the second. Let us assume that in both the first and second communities there are 100 individuals and 10 species. But in the first community, individuals are distributed between species, 10 each, and in the second, one species has 82 individuals, and the rest have 2. As in the first example, the first community will have a greater evenness in the distribution of individuals than the second.

The total number of currently known species is about 2.5 million, and almost 1.5 million of them are insects, another 300 thousand are flowering plants. There are about as many other animals as there are flowering plants. There are a little more than 30 thousand known algae, about 70 thousand fungi, less than 6 thousand bacteria, and about a thousand viruses. Mammals - no more than 4 thousand, fish - 40 thousand, birds - 8400, amphibians - 4000, reptiles - 8000, mollusks - 130,000, protozoa - 36,000, various worms - 35,000 species.

About 80% of the biodiversity is made up of land species (ground-air and soil life environments) and only 20% is species of aquatic life environment, which is quite understandable: the diversity of environmental conditions in water bodies is lower than on land. 74% of biodiversity is associated with the tropics. 24% - from temperate latitudes and only 2% - from polar regions.

Because the rainforests are disappearing catastrophically quickly under the pressure of plantations of hevea, bananas and other highly profitable tropical crops, as well as sources of valuable timber, most of the biological diversity of these ecosystems may die without receiving scientific names. This is a depressing prospect, and so far the efforts of the global environmental community have not yielded any tangible results in preserving tropical forests. Absence complete collections It also does not allow us to reliably judge the number of species living in marine environments, which have become “... a kind of boundary of our knowledge about biological diversity.” In recent years, completely new groups of animals have been discovered in marine environments.

To date, the planet's biodiversity has not been fully identified. According to forecasts, the total number of species of organisms living on Earth is at least 5 million (and according to some forecasts - 15, 30 and even 150 million). The least studied are the following systematic groups: viruses, bacteria, nematodes, crustaceans, unicellular organisms, algae. Mollusks, mushrooms, arachnids and insects have also been insufficiently studied. Only vascular plants, mammals, birds, fish, reptiles, and amphibians have been well studied.

Microbiologists have learned to identify fewer than 4,000 species of bacteria, but research on bacterial DNA analysis carried out in Norway has shown that more than 4,000 species of bacteria live in 1 g of soil. A similarly high bacterial diversity is predicted in marine sediment samples. The number of bacterial species that have not been described is in the millions.

The number of species of living organisms living in marine environments has not been fully identified. “The marine environment has become the frontier of our knowledge of biological diversity.” New groups of marine animals of high taxonomic rank are constantly being identified. Communities of organisms unknown to science have been identified in recent years in the canopy of tropical forests (insects), in geothermal oases depths of the sea(bacteria and animals), in the depths of the earth (bacteria at a depth of about 3 km).

The number of described species is indicated by the shaded parts of the bars.

The International Convention on Biological Diversity, signed in June 1992 in Rio de Janeiro, can be seen mainly as an expression of universal concern about the loss of what cannot be restored - species of living beings, each of which occupies a certain place in the structure of the biosphere. Will united humanity be able to preserve biological diversity? This largely depends on the attention to historical processes and current factors under the influence of which biological diversity as we know it, or, more precisely, we know it to a small extent, has developed.

We don't know how many species there are. There may be up to 30 million in the tropical forest canopy alone, although most researchers accept a more conservative figure of 5-6 million. There is only one way to save them - by protecting the tropical forest as an ecosystem from clear cutting and pollution. In other words, to preserve species diversity, it is necessary first of all to take care of the diversity of a higher level—ecosystems. At this level, tundras and polar deserts deserve no less attention than tropical forests, with which they are comparable in spatial parameters as structural divisions of the biosphere, although much poorer in species.

Biological diversity (BD) is the diversity of forms and processes in the organic world, manifested at the molecular genetic, population, taxonomic and coenotic levels of the organization of living things. Although the levels of organization are named here in their traditional sequence from bottom to top (each subsequent level includes the previous ones), this order of consideration does not provide much for understanding the nature of the BD. If we are interested in the reasons for the emergence of BR (according to religious beliefs, BR arose as a result of a creative act, the logic of which should also be accessible intelligent being), then it is better to move from top to bottom, starting with the biosphere - the earth’s shell containing organisms and the products of their vital activity. The biosphere is superimposed on the physical shells of the Earth - the earth's crust, hydrosphere and atmosphere, the composition of which is largely determined by the biogenic cycle of substances.

Each of these shells, in turn, is heterogeneous in physical properties And chemical composition in the direction of the action of gravity and rotational forces that determine the division into the troposphere and stratosphere, oceans, marginal seas and inland water bodies, continents with their geomorphological heterogeneities, etc. The heterogeneity of conditions is also created by the uneven distribution of incoming solar energy. The latitudinal climatic zonation on the continents is complemented by climatic vectors directed from the coast inland. The natural change in conditions in height above sea level and depth creates vertical zonation, which is partly similar to latitudinal zonation. Life is superimposed on all these heterogeneities, forming a continuous film that is not interrupted even in deserts.

Continuous living cover is the result of long evolution. Life arose at least 3.5 billion years ago, but for about 6/7 of that time the land remained virtually lifeless, as were the deep oceans. The expansion of life was carried out through adaptation to different conditions of existence, differentiation of life forms, each of which, within its habitats, is most effective in using natural resources (you can try to replace all the diversity with one species, as is essentially what modern man does, but the efficiency of use biosphere resources will decrease sharply as a result).

Conditions changed not only in space, but also in much the same way in time. Some forms of life have proven to be more adaptable to change than others. Life was interrupted in certain zones, but, at least in the last 600 million years, there were constantly forms that could survive the crisis and fill the gaps formed (remains of more ancient organisms are few, and we are not sure that during Precambrian history life did not was interrupted). Thus, BR ensures the continuity of life over time.

As life covered the surface of the planet with a continuous film, the organisms themselves increasingly acquired the importance of the main factor in the formation of living space, the functional structure of the biosphere, associated with the biogenic transformation of matter and energy carried out within its boundaries, the effectiveness of which is ensured by the distribution of roles between organisms, their functional specialization . Each functional cell of the biosphere - an ecosystem - is a local collection of organisms and components of their environment interacting in the process of biogenic circulation. The spatial expression of an ecosystem can be a landscape, its facies (in this case we speak of a biogeocenosis, which, according to V.N. Sukachev, includes a geological substrate, soil, vegetation, animal and microbial population), any component of the landscape (reservoir, soil, plant community) or a single organism with its external internal symbionts.

The functional space of an ecosystem (multidimensional, as opposed to physical) is divided into ecological niches corresponding to the distribution of roles between organisms. Each niche has its own life form, a kind of role that determines the basic morphophysiological characteristics of organisms and, in the order of feedback, depends on them. The formation of an ecological niche is a reciprocal process in which the organisms themselves play an active role. In this sense, niches do not exist separately from life forms. However, the predetermination of the structure of the ecosystem, associated with its functional purpose, makes it possible to recognize “empty niches” that must certainly be filled in order for the structure to be preserved.

Thus, biological diversity is necessary to maintain the functional structure of the biosphere and its constituent ecosystems.

A stable combination of functionally interrelated life forms forms a biotic community (biocenosis), the composition of which is the more diverse, the more complex the structure of the ecosystem, and this latter depends mainly on the stability of the processes occurring in the ecosystem. Thus, in the tropics, diversity is higher, since photosynthesis is not interrupted throughout the year.

Another important function of the BR is associated with the development and restoration of the community - reparation. Types perform various roles during autogenetic succession—change of development stages from pioneer to climax. Pioneer species are undemanding with regard to the quality and stability of the environment and have a high reproductive potential. By stabilizing the environment, they gradually give way to more competitive species. This process moves towards the final phase (climax), which can long time hold the territory while being in a state of dynamic equilibrium. Since a variety of external influences constantly disrupt succession, monoclimax most often remains a theoretical possibility. Development stages are not completely replaced, but coexist in complex succession systems, providing them with the opportunity to recover from destructive influences. The restoration function is usually performed by rapidly reproducing pioneer species.

It would be an exaggeration to say that we can accurately determine the functional purpose of each species in any of the many ecosystems. The removal of a species also does not always lead to their destruction. Much depends on the complexity of the ecosystem (in Arctic communities with a relatively simple trophic structure, the proportion of each species is much higher than in the tropics), its successional and evolutionary stage of development, which determines the overlap (duplication) of ecological niches and the redundancy of structural elements. At the same time, duplication and redundancy in systems theory are considered as stability factors, that is, they have a functional meaning.

All of the above allows us to conclude that the random element in the BR does not play a significant role. BR is functional. Each of its components is formed by the system in which it is included, and in turn, according to the principle of feedback, determines the features of its structure.

In general, the BR reflects the spatiotemporal and functional structure of the biosphere, ensuring: 1) the continuity of the living cover of the planet and the development of life over time, 2) the efficiency of biogenic processes in the ecosystem, 3) maintaining dynamic balance and restoration of communities.

These appointments determine the structure of the BR at all hierarchical levels of its organization.

^ Structure of biological diversity

The genetic material in most organisms is contained in huge molecules of DNA and RNA, filamentous polynucleotides that look like a ring chromosome or a set of linear chromosomes, which are extremely diverse in the overall DNA content, number, shape, and development of various types of heterochromatin. and also by the types of reconstructions in which they participate. All this creates a diversity of genomes as complex systems, comprising - in higher organisms - tens of thousands of discrete genetic elements, or genes. Their discreteness is structural in nature (for example, unique or repeatedly repeated sequences of nucleotides) or expressed functionally, as in protein-coding elements that are reproduced as a whole, jointly controlled, involved in cross-exchange between paired chromosomes, and, finally, elements that move throughout the genome. When the molecular mechanisms were not understood, the concept of a gene was abstract and it was endowed with all these functions, but it is now known that they are performed by structurally distinct genetic particles that make up the diversity of gene types. As a result of changes in the nucleotide composition, or mutations, similar sections of paired chromosomes have different structures. Such regions-chromosomal loci, known in several states, are called polymorphic. Genetic polymorphism is transformed into protein polymorphism, which is studied by molecular genetic methods, and, ultimately, into the genetic diversity of organisms. At these derived levels, gene diversity appears indirectly, since traits are determined by the genetic system and not by individual genes.

N.I. Vavilov showed on extensive material that the diversity of hereditary characters in closely related species is repeated with such accuracy that it is possible to predict the existence of a variant that has not yet been found in nature. Thus, the orderliness of genetic variability was revealed (contrary to the ideas about the unpredictability of mutations), in which the properties of the genome as a system are manifested. This fundamental generalization, formulated as the law of homological series, underlies the study of the structure of BR.

The transfer of hereditary information from one generation to another is carried out in the process of reproduction of organisms, which can be asexual, sexual, in the form of alternating asexual and sexual generations. This diversity is superimposed on differences in the mechanisms of sex determination, separation of sexes, etc. It is enough to recall the species of fish consisting of only females (reproduction is stimulated by males of other species) or the ability of females to turn into males, if there are not enough of them, to imagine the diversity reproduction processes in vertebrates, not to mention organisms such as fungi, where it is many times higher.

Organisms involved in reproduction constitute the reproductive resources of a species, which are structured according to a variety of reproductive processes. The units of the reproduction system are demylocal groups of interbreeding individuals and populations, larger groups within a landscape or ecosystem. Accordingly, geographic and coenotic populations are distinguished, although their boundaries may coincide.

During the process of reproduction, a recombination of genes occurs, which seem to belong to the population as a whole, constituting its gene pool (the gene pool is also spoken of in a broader sense as the totality of genes of fauna or flora; this is partly justified, since at least an episodic exchange of genes is possible during hybridization or transfer of genetic material by microorganisms). The unity of the population, however, is ensured not only by a common gene pool, but also by entering into geographical or biological systems of a higher level.

Populations from neighboring landscapes or ecosystems always show some variation, although they may be so close that taxonomists consider them to be a single species. In essence, a species is a collection of populations of a number of historically interconnected landscape and (or) coenotic complexes. The integrity of a species as a system is determined by the historical commonality of its constituent populations, the flow of genes between them, as well as their adaptive similarity due to similar living conditions and coenotic functions. The latter factors are also effective in relation to asexual organisms, determining the universal significance of the species as the basic unit of biological diversity (the often exaggerated idea of ​​​​sexual gene transfer as the most significant criterion biological species forces us to see in it a category characteristic exclusively of dioecious organisms, which contradicts taxonomic practice).

The properties of a species are determined, as we have already noted, by that part of the ecological space that it stably occupies, i.e. ecological niche. At the early stages of development of the biological community, there is a significant overlap of ecological niches, but in the established coenotic system, species, as a rule, occupy fairly separate niches, however, a transition from one niche to another is possible during growth (for example, in attached forms with mobile larvae) , entering various communities in some cases as a dominant species, in others as a secondary species. There is some disagreement among experts regarding the nature of biotic communities: whether they are random collections of species that have found suitable conditions for themselves, or integral systems like organisms. These extreme points views most likely reflect the diversity of communities, completely unequal in their systemic properties. Also, species are sensitive to their coenotic environment to varying degrees, from independent (conditionally, since they belong to communities of higher ranks) to “faithful”, according to which associations, unions and classes are distinguished. This classification approach was developed in Central Europe and is now widely accepted. A rougher “physiognomic” classification based on dominant species is adopted in northern countries, where relatively homogeneous forest formations still occupy vast areas. Within the landscape-climatic zones, groups of characteristic formations form the biomes of tundras, taiga forests, steppes, etc. - the largest landscape-cenotic divisions of the biosphere.

^ Evolution of biological diversity

BR develops into a process of interaction between the biosphere and the physical shells of the Earth on which it is superimposed. The movement of the earth's crust and climatic events cause adaptive changes in the macrostructure of the biosphere. For example, a glacial climate has a higher diversity of biomes than an ice-free climate. Not only polar deserts, but also tropical rainforests owe their existence to the atmospheric circulation system, which is formed under the influence polar ice(see above). The structure of biomes, in turn, reflects the contrast of relief and climate, the diversity of geological substrates and soils - the heterogeneity of the environment as a whole. The species diversity of their constituent communities depends on the granularity of the division of ecological space, and this latter depends on the stability of conditions. In general, the number of species s==g – p y, where a is the diversity of species in communities, p is the diversity of communities and y is the diversity of biomes. These components change at certain intervals, rebuilding the entire BR system. For example, in the Mesozoic (glacial-free climate) the diversity of plants approximately corresponds to the modern one in similar formations of hard-leaved shrubs and summer-green forests, but the total number of species is approximately half that of the modern one due to low diversity.

Genetic diversity in turn changes as a function of species' adaptive strategies. The fundamental property of a population is that, theoretically, during its reproduction, the frequencies of genes and genotypes are preserved from generation to generation (Hardy-Weinberg rule), changing only under the influence of mutations, genetic drift and natural selection. Variants of the structure of genetic loci - alleles - that arise as a result of mutations often do not have an adaptive effect and constitute a neutral part of polymorphism, subject to random changes - genetic drift, and not directed selection - hence the model of “non-Darwinian” evolution.

Although the evolution of population diversity is always the combined result of drift and selection, their ratio depends on the state of ecosystems. If the structure of the ecosystem is disturbed and stabilizing selection is weakened, then evolution becomes incoherent: genetic diversity increases due to mutagenesis and drift without a corresponding increase in species diversity. Stabilizing an ecosystem directs population strategy toward more efficient use of resources. In this case, the more pronounced heterogeneity (“coarse grain”) of the environment becomes a factor in the selection of genotypes that are most adapted to the “grain” of the landscape-coenotic mosaic. At the same time, neutral polymorphism acquires adaptive significance, and the ratio of drift and selection changes in favor of the latter. Progressive differentiation of demes becomes the basis for the fragmentation of species. Developing steadily over thousands of years, these processes create exceptionally high species diversity.

The system, thus, directs the evolution of the organisms included in it (let us note, to avoid misunderstandings, that organisms not included in the coenotic systems do not exist: even the so-called coenophobic groups that disrupt the development of the community are included in systems of a higher rank).

The overarching evolutionary trend is one of increasing diversity, punctuated by sharp declines resulting in mass extinctions (about half at the end of the era of dinosaurs, 65 million years ago). The frequency of extinction coincides with the activation of geological processes (movement

Earth's crust, volcanism) and climatic changes, pointing to a common cause.

In the past, J. Cuvier explained such crises by the direct destruction of species as a result of marine transgressions and other disasters. C. Darwin and his followers did not attach any importance to crises, attributing them to the incompleteness of the geological Chronicle. Nowadays, no one doubts crises; Moreover, we are experiencing one of them. A general explanation of crises is given by the ecosystem theory of evolution (see above), according to the second, the reduction in diversity occurs due to the stability of the environment, which determines the tendency towards

simplification of the structure of ecosystems (some species turn out to be redundant),

interruption of successions (species of the final climax stage are doomed to extinction) and

increase minimum sizes populations (in a stable environment, a small number of individuals ensures reproduction, a “dense packing” of species is possible, but in a crisis, a population that is small and incapable of rapid growth can easily disappear).

These patterns are also valid for the anthropogenic crisis of our days.

^ Human Impact on Biodiversity

The direct ancestors of humans appeared about 4.4 million years ago, at the beginning of the Gilbertian paleomagnetic era, marked by the expansion of glaciation in the Antarctic, aridization and the spread of herbaceous vegetation in low latitudes. The habitat, bordering the tropical forest and savannah, the relatively weak specialization of the teeth, the anatomy of the limbs, adapted both for movement in open areas and for arboreal acrobatics, indicate a wide ecological louse of Australopithecus africanus, the oldest representative of this group. Subsequently, evolution enters a coherent phase, and species diversity increases. Two lines of adaptive radiation—australopithecus graceful and massive—developed along the path of food specialization, in the third—Homo labilis—at the level of 2.5 million years, signs of tool activity appeared as a prerequisite for the expansion of the food niche.

The latter turned out to be more promising in unstable conditions ice age, the crisis phases of which correspond to the wide distribution of polymorphic species of Homo erectus and later Homo sapiens, with a discrepancy between high genetic and low species diversity characteristic of incoherent evolution. Each of them

Then it entered the phase of subspecific differentiation. About 30 thousand years ago, the specialized Neanderthal subspecies of the “reasonable” was supplanted by the nominative subspecies, the fragmentation of which took place along the line of cultural rather than biological evolution. Wide adaptive capabilities provided it with relative independence from local ecosystems, outgrowing Lately into coenophobia. As we have already noted, coenophobia is possible only up to a certain level of the hierarchy of natural systems. Cenophobia regarding the biosphere as a whole dooms the species to self-destruction.

Humans influence all factors of BR - spatio-temporal heterogeneity of conditions, the structure of ecosystems and their stability. Disruption of the climax community as a result of logging or fires may result in some increase in species diversity due to pioneer and successional species. Spatial heterogeneity in some cases increases (for example, vast forest areas are dismembered, accompanied by a slight increase in species diversity). More often, a person creates more homogeneous conditions. This is expressed in the leveling of the relief (in urbanized areas), clearing forests, plowing up steppes, draining swamps, introducing alien species that displace local ones, etc.

Human influence on temporary factors is expressed in the multiple acceleration of natural processes, such as desertification or drying out of inland seas (for example, the Aral Sea, which in the past repeatedly dried out without human intervention). The human impact on the global climate destabilizes biosphere rhythms and creates a general precondition for simplifying the structure of terrestrial and aquatic ecosystems, and, consequently, for the loss of BD.

Over the past two decades, forests have been reduced by almost 200 million hectares, and currently damage amounts to about 1% of the remaining area per year. These losses are distributed very unevenly: the greatest damage was caused to the tropical forests of Central America, Madagascar, South-East Asia, but also in the temperate zone, forest formations such as redwoods in North America and China (metasequoia), Manchurian black fir in Primorye, etc. are on the verge of extinction. Within the steppe biome, there are practically no undisturbed habitats left. In the United States, more than half of the wetlands have been lost; in Chad, Cameroon, Nigeria, India, Bangladesh, Thailand, Vietnam, and in New Zealand, more than 80%.

Species loss due to habitat disturbance is difficult to estimate because methods for recording species diversity are very imperfect. If we take a “moderate” estimate of insect diversity for tropical forests at 5 million species and the number of species is proportional to the fourth root of the area, then losses due to deforestation will amount to 15,000 per year. Actual losses may differ significantly from those estimated. For example, in the Caribbean region, no more than 1% of primary forests remain, but the diversity of native bird species has declined by only 11%, as many species remain in secondary forests. Even more problematic is the assessment of the reduction in BR of soil biota, reaching 1000 species of invertebrates per square meter. m. The loss of soil cover as a result of erosion is estimated at a total of 6 million hectares per year - about 6 * 107 species can live in this area.

Probably the most significant losses of species diversity are associated with economic development and pollution of ecosystems characterized by a particularly high level of endemism. These include the hard-leaved formations of the Mediterranean and the Kalekoy province in southern Africa (6,000 endemic species), as well as rift lakes (Baikal - about 1,500 endemics, Malawi - more than 500).

According to (McNeely, 1992), the loss of species diversity by group since 1600 is:

Disappeared under threat

Higher plants 384 species (0.15%) 18699 (7.4%)

Pisces 23 -»- (0.12%) 320 (1.6%)

Amphibians 2-»-(0.05%) 48(1.1%)

Reptiles 21 -»- (0.33%) 1355 (21.5%)

Birds 113-»- (1.23%) 924 (10.0%)

Mammals 83 -»- (1.99%) 414 (10.0%)

Violation of the structure and function of ecosystems is associated with their use as raw materials, recreational and deposit (for waste disposal) resources, and raw material and deposit use can give directly opposite results. Thus, overgrazing, removal of canopy-forming trees or game animals disrupt the trophic structure and often return the ecosystem to the early stages of development, delaying succession. At the same time, the entry of organic pollutants into water bodies accelerates succession, passing the ecosystem through a eutrophic state to a hypertrophic one.

The size of the human population depends little on the size of the species being exterminated, so the feedback in the “predator-prey” system is broken, and a person gets the opportunity to completely exterminate one or another species of prey. In addition, in his role as a superpredator, man exterminates not the weak and sick, but rather the most complete individuals (this also applies to the practice of loggers to cut down the most powerful trees first).

However, the most important is the indirect damage from impacts that disrupt the balanced relationships and processes in ecosystems and thereby change the direction of the evolution of species. Evolutionary changes occur as a result of mutagenesis, genetic drift and natural selection. Radiation and chemical pollution have a mutagenic effect. The removal of biological resources - a significant part of natural populations - turns into a factor of genetic drift, forcing natural fluctuations in numbers, loss of genetic diversity and, giving an advantage to genotypes with accelerated sexual maturation and high reproductive potential (due to this, indiscriminate removal usually leads to accelerated sexual maturation and reduction ). The direction of natural selection can change under the influence of various biological and chemical factors. physical (noise, electromagnetic, etc.) pollution. Biological pollution - the deliberate or accidental introduction of alien species and biotechnological products (including laboratory strains of microorganisms, artificial hybrids and transgenic organisms) - is a common factor in the loss of natural BR. The most famous examples are the introduction of placentals into Australia (in fact, reintroduction, since they lived on this continent many millions of years ago), Elodea into the reservoirs of Eurasia, ctenophores into the Sea of ​​Azov, amphipods Corophium cnrvispinHm into the Rhine from the Ponto-Caspian region (from the first appearance in 1987, the number of this species increased to 100 thousand individuals per 1 sq.m., competing with local species of zoobenthos, which serve as food for commercial fish and waterfowl). Biological pollution is undoubtedly facilitated by changes in habitats as a result of physical and chemical impacts (increased temperature and salinity, eutrophication in the case of the introduction of amphipod thermophilic filter feeders),

In some cases, the impact causes a chain reaction with far-reaching consequences. For example, the entry of eutrophicating substances into coastal waters from the continent and from mari culture causes blooming of dinoflaellates, secondary pollution with toxic substances - the death of cetaceans and an increase in the solubility of carbonates - the death of corals and other skeletal forms of benthos. Acid-forming pollution of water bodies, in addition to the direct impact on respiration (deposition of aluminum on the gills) and reproductive function of amphibian fish, poses a threat of extinction to many species of aquatic vertebrates and waterbirds due to a reduction in the biomass of the larvae of stoneflies, mayflies, and chironomids.

The same factors change the ratio of genotypes in animal and plant populations, giving an advantage to those more resistant to various types stress.

Pollution also becomes a powerful factor of natural selection. A classic example is the increase in the frequency of the melanistic form of Biston betularia butterflies in industrial areas, which they tried to explain by the fact that on soot-covered trunks they are less noticeable to birds than the light forms. This long-standing textbook explanation seems naive, since under conditions of pollution, melanistic forms are more resistant in many species, including domestic cats and humans. This example cautions against simplistic views of the human impact on BD.

^ Conservation of biological diversity

In ancient times, as we have already noted, totemism and those that grew out of it religious ideas contributed to the conservation of individual species and their habitats. We owe the preservation of such relics as ginkgo mainly to the religious rituals of eastern peoples. In North America, European Colonists adopted from local tribes their normative attitude towards nature, while in European feudal countries nature was preserved mainly as royal hunting grounds and parks, with which the aristocracy protected itself from too close contact with the common people.

In early democracies, moral and aesthetic motives were supplanted by economic ones, which often came into conflict with the preservation of the BR. The utilitarian attitude towards nature has acquired especially ugly forms in totalitarian countries. P. A. Manteuffel, expressing the official position, wrote in 1934: “These groups (animals) formed without the influence (will) of man and for the most part do not correspond to the economic effect that could be obtained with a rational change in zoological boundaries and communities, and therefore we put forward the question of the reconstruction of the fauna, where, in particular, the artificial relocation of animals should occupy a prominent place.”

However, the new aristocracy - the party leadership and those close to it - also needed protected hunting grounds, called hunting reserves.

In the 60s, the reserves underwent a twofold reduction due to extensive economic development. In addition, the allocation of huge areas for monoculture had an extremely adverse effect on the state of the BR. In the early 80s to fulfill " food program» plowed up roadsides, boundaries and inconveniences, depriving wild species last refuges in developed areas.

Unfortunately, these trends have become further development during the period of perestroika in connection with the transfer of waste land to farmers and the development of private entrepreneurship in conditions of legislative chaos. Self-seizure of land for vegetable gardens, deforestation in green belts around cities, illegal extraction of rare species and free sale of biological resources have become common practice. The reserves have never enjoyed much popularity locally and, as control weakens, they are coming under increasing pressure from economic structures and poachers. The development of international tourism is causing damage to areas that were previously protected as sensitive areas. These include military training grounds and border lands (in Germany, a 600x5 km exclusion zone over the years of confrontation has turned into a kind of nature reserve, which is now trampled by crowds of tourists).

At the same time, there is reason to hope for an improvement in the situation (and, in particular, the transformation of former regime areas into nature reserves) thanks to the general recognition of the priority of conservation of the BR. The immediate task is to develop and strengthen national programs. Let us note some fundamental points that arise in this regard. Inventory and protection of biological diversity. Identification of the species structure in many cases is necessary for organizing protection. For example, the New Zealand tuatara, the only representative of the oldest group of beaked reptiles, has been protected since 1895, but only recently it became clear that there are two species of tuatara with subspecies, one of the species, S. guntheri, and a subspecies of the other, S.punctata reischeki were on the verge of extinction, and ten out of forty populations had already disappeared; Traditional taxonomy still has a long way to go in the field of conservation.

At the same time, the quite often expressed idea that for conservation it is necessary, first of all, to inventory all taxonomic diversity, has a somewhat demagogic connotation. There can be no question of describing the entire multimillion-dollar diversity of species in the foreseeable future. Species disappear without ever receiving the attention of a taxonomist. A more realistic approach is to develop a fairly detailed syntaxonomic classification of communities and organize the protection of in-situ on this basis. Security of a top-level system to a certain extent ensures the preservation of its components, some of which we do not know or know in the most general outline(but at least we don't rule out the possibility of finding out in the future). In the following sections we will look at some principles for organizing protection on a syntaxonomic basis to capture all or most of the taxonomic diversity.

Combining human rights with animal rights. Recognizing the rights of animals does not mean abandoning their use. After all, people are also used legally. It cannot be denied that it is fair that a person has more rights than an animal, just as an adult has more rights than a child. However, without falling into environmental terrorism, which is for the most part provocative in nature, it must still be recognized that reasonable use has nothing to do with killing for pleasure or on a whim, nor with cruel experimentation, which, moreover, is mostly senseless,

The concept of “biodiversity” came into wide scientific use in 1972 at the Stockholm UN Conference on the Environment, where ecologists managed to convince political leaders of the world community that the protection of wildlife should become a priority in any human activity on Earth. Twenty years later, in 1992, in Rio de Janeiro, during the UN Conference on Environment and Development, the Convention on Biological Diversity was adopted, which was signed by more than 180 countries, including Russia. Active implementation of the Convention on Biodiversity in Russia began after its ratification by the State Duma in 1995. A number of environmental laws were adopted at the federal level, and in 1996, the Decree of the President of the Russian Federation approved the “Concept of the Russian Federation’s transition to sustainable development,” which considers the conservation of biodiversity as one of the most important areas of Russia’s development. Russia, like other countries that have signed and ratified the Convention on Biological Diversity, is not acting alone. The Global Environment Facility (GEF) project for the conservation of Russia's biodiversity, financed by the International Bank for Reconstruction and Development, started in December 1996. Since then, the National Strategy for the Conservation of Biodiversity of Russia has been developed and adopted in 2001, mechanisms for preserving biodiversity are being developed, support is being provided to national parks and reserves, and measures are being implemented to preserve biodiversity and improve the environmental situation in various regions.

This series of teaching aids and reference materials is intended to at least to some extent fill the vacuum that exists in Russia. It would seem that the problem of biodiversity conservation, discussed at various levels, should have long ago been reflected in curricula and educational standards, at least for environmental specialties. However, as a thorough analysis of the State Educational Standards has shown, sections related to the study of the phenomenon of biodiversity, methods of its assessment, the importance of biodiversity conservation for sustainable development etc. are not explicitly included in any of them. There are practically no textbooks on this topic.

1. What is biological diversity?

Biodiversity – This includes hundreds of thousands of species, and the diversity within the populations of each species, and the diversity of biocenoses, that is, at every level - from genes to ecosystems, diversity is observed. This phenomenon has been of interest to humans for a long time. First, out of simple curiosity, and then quite consciously and often for practical purposes, a person studies his living environment. This process has no end, since with each century new problems arise and ways of understanding the composition and structure of the biosphere change. They are solved by the entire complex of biological sciences. The study of the diversity of the organic world of our planet has become especially relevant after the role of diversity itself in maintaining the stability of the biosphere began to become clear.

The conservation of biological diversity is a central task of wildlife conservation biology. According to the definition given by the World Wildlife Fund (1989), biological diversity is “the entire diversity of life forms on earth, the millions of species of plants, animals, microorganisms with their sets of genes and the complex ecosystems that make up living nature.” Thus, biological diversity should

considered at three levels:

genetic diversity, reflecting intraspecific diversity and due to the variability of individuals;

species diversity, reflecting the diversity of living organisms (plants, animals, fungi and microorganisms). Currently, about 1.7 million species have been described, although their total number, according to some estimates, is up to 50 million;

diversity of ecosystems covers differences between ecosystem types, habitat diversity, and ecological processes. They note the diversity of ecosystems not only in structural and functional components, but also in scale - from microbiogeocenosis to the biosphere.

BIOLOGICAL DIVERSITY (biodiversity), a concept that came into widespread use in the 1980s in the fields of fundamental and applied biology, exploitation of biological resources, politics in connection with the strengthening of the environmental movement, awareness of the uniqueness of each biological species and the need to preserve the entire diversity of life for sustainable development biosphere and human society. This was reflected in the International Convention on Biological Diversity, adopted in Rio de Janeiro in 1992 (signed by Russia in 1995). In scientific literature, the concept of “biological diversity” is used in a broad sense to refer to the richness of life in general and its components or as a set of parameters of floras, faunas and communities (the number of species and a set of adaptive types, indices reflecting the ratio of species by number of individuals - evenness, dominance, and so on). Forms of biological diversity can be identified at all levels of life organization. They talk about diversity of species, taxonomic, genotypic, population, biocenotic, floristic, faunistic, etc. At each level there are their own systems, categories and methods for assessing diversity. By the beginning of the 21st century, biologists counted up to 2 million species of all groups of organisms: multicellular animals - approximately 1.4 million species (including insects - about 1 million), higher plants - 290 thousand species (including angiosperms - 255 thousand), mushrooms - 120 thousand species, algae - 40 thousand, protests - 40 thousand, lichens - 20 thousand, bacteria - 5 thousand species. Some authors, taking into account the estimated number of species not yet described, estimate the richness of modern organic world a much larger number of species - up to 15 million. In ecology, when analyzing the structure and dynamics of communities, the system of biological diversity of the American ecologist R. Whittaker is widely used. Of the categories of biological diversity he proposed, the most commonly used are alpha diversity (the species structure of a particular community), beta diversity (changes in a number of communities, for example, depending on temperature conditions) and gamma diversity (the structure of biota on the scale of the entire landscape). Syntaxonomy, the classification of plant communities based on their species diversity, is rapidly developing.

Biological diversity is the main result and at the same time a factor in the evolutionary process. The emergence of new species and life forms complicates the habitat and determines the progressive development of organisms. The most complex, evolutionarily advanced forms arise and flourish in the equatorial and tropical zones, where the maximum species richness is observed. And life itself could have developed as a planetary phenomenon based on the division of functions in primary ecosystems, i.e., at a certain level of diversity of organisms. The circulation of substances in the biosphere can only occur with sufficient biological diversity, on which the mechanisms of stability and regulation of the dynamics of ecological systems are based. Such important features of their structure as interchangeability, ecological vicariate, multiple provision of functions are possible only with significant species and adaptive (adaptive forms) diversity.

The level of biodiversity on Earth is primarily determined by the amount of heat. From the equator to the poles, all indicators of biological diversity decrease sharply. Thus, the flora and fauna of the equatorial and tropical zones account for at least 85% of the total species wealth of the organic world; Species living in temperate zones make up approximately 15%, and in the Arctic - only about 1%. In the temperate zone, in which most of Russia is located, the most high level biodiversity in its southern zone. For example, the number of bird species from forest-steppe and deciduous forests to the tundra decreases by 3 times, and the number of flowering plants by 5 times. In accordance with the change in natural belts and zones, the structure of all biological diversity naturally changes. Against the background of a general decline in species richness of the organic world towards the poles separate groups maintain a fairly high level and their proportion in the fauna and flora, as well as their biocenotic role, increase. The more severe the living conditions, the higher the proportion of relatively primitive groups of organisms in the biota. For example, the diversity of flowering plants, which form the basis of the Earth’s flora, decreases much more sharply as we move to high latitudes than bryophytes, which in the tundra are not inferior to them in species richness, and in the polar deserts they are twice as rich. In conditions of extreme climatic pessimism, for example, in Antarctic oases, mainly prokaryotes and isolated species of lichens, mosses, algae, and microscopic animals live.

Increased specificity of the environment, extremeness (very high or low temperature, high salinity, high pressure, the presence of toxic compounds, high acidity, and so on) reduce the parameters of biological diversity, in particular the species diversity of communities. But at the same time, certain species or groups of organisms that are resistant to this factor (for example, some cyanobacteria in heavily polluted water bodies) can reproduce in extremely large quantities. In ecology, the so-called basic biocenotic law or Tienemann’s rule is formulated: biotopes with conditions sharply different from optimal ones are inhabited by fewer species, which, however, are represented by a large number of individuals. In other words, the depletion of species composition is compensated by an increase in the population density of individual species.

Among the areas of studying biological diversity, first of all, an inventory of species composition based on taxonomy is distinguished. The latter is associated with floristics and faunistics, arealogy, phyto- and zoogeography. It is extremely important to know the factors and understand the mechanisms of the evolution of biological diversity, the genetic basis of the diversity of organisms and populations, the ecological and evolutionary role of polymorphism, the patterns of adaptive radiation and the processes of delimitation of ecological niches in ecosystems. The study of biological diversity in these aspects is closely related to the most important areas modern theoretical and applied biology. A special role is given to the nomenclature, typology and inventory of communities, vegetation and animal populations, the creation of databases on various components of ecological systems, which is necessary to assess the state of the entire living surface of the Earth and the biosphere, to solve specific problems of environmental protection, conservation, use of biological resources, many pressing issues of biodiversity conservation at the regional, national and global levels.

Lit.: Chernov Yu.I. Biological diversity: essence and problems // Advances in modern biology. 1991. T. 111. Issue. 4; Alimov A.F. et al. Problems of studying the diversity of the animal world in Russia // Journal of General Biology. 1996. T. 57. No. 2; Groombridge V., Jenkins M.D. Global biodiversity. Camb., 2000; Alekseev A. S., Dmitriev V. Yu., Ponomarenko A. G. Evolution of taxonomic diversity. M., 2001.

LECTURE No. 6.7

SOIL ECOLOGY

SUBJECT:

Biodiversity- short for "biological diversity" - means the diversity of living organisms in all its manifestations: from genes to the biosphere. Much attention began to be paid to the study, use and conservation of biodiversity after many states signed the Convention on Biological Diversity (UN Conference on Environment and Development, Rio de Janeiro, 1992).

There are three main type of biodiversity:

- genetic diversity, reflecting intraspecific diversity and due to the variability of individuals;

- species diversity, reflecting the diversity of living organisms (plants, animals, fungi and microorganisms). Currently, about 1.7 million species have been described, although their total number, according to some estimates, is up to 50 million;

- diversity of ecosystems covers differences between ecosystem types, habitat diversity, and ecological processes. They note the diversity of ecosystems not only in structural and functional components, but also in scale - from microbiogeocenosis to the biosphere;

All types of biodiversity interconnected: Genetic diversity provides species diversity. The diversity of ecosystems and landscapes creates conditions for the formation of new species. Increasing species diversity increases the overall genetic potential of living organisms in the Biosphere. Each species contributes to diversity - from this point of view, there are no useless or harmful species.

Distribution species are distributed unevenly across the surface of the planet. Species diversity in natural habitats is greatest in the tropics and decreases with increasing latitude. The richest ecosystems in species diversity are tropical rainforests, which occupy about 7% of the planet's surface and contain more than 90% of all species.

IN geological history Earth in the biosphere was constantly happening emergence and disappearance of species- all species have a finite lifetime. Extinction was compensated by the emergence of new species, and as a result, the total number of species in the biosphere increased. The extinction of species is a natural process of evolution that occurs without human intervention.

Currently, under the influence of anthropogenic factors, there is reduction biological diversity due to the elimination (extinction, destruction) of species. IN last century influenced human activity the rate of extinction of species was many times higher than natural (according to some estimates, 40,000 times). There is an irreversible and uncompensated destruction of the planet’s unique gene pool.

Elimination of species as a result of human activity may occur in two directions- direct extermination (hunting, fishing) and indirect (destruction of habitat, disruption of trophic interactions). Overfishing is the most obvious direct cause of species decline, but it has a much lower impact on extinction than indirect causes of habitat change (such as chemical pollution of a river or deforestation).

Diversity of biotic cover, or biodiversity, is one of the factors for the optimal functioning of ecosystems and the biosphere as a whole. Biodiversity ensures the resistance of ecosystems to external stressors and maintains a fluid balance in them. Living things differ from non-living things in the first place by several orders of magnitude in greater diversity and the ability not only to preserve this diversity, but also to significantly increase it as evolution progresses. In general, the evolution of life on Earth can be considered as a process of structuring the biosphere, a process of increasing the diversity of living organisms, forms and levels of their organization, the process of the emergence of mechanisms that ensure the stability of living systems and ecosystems in the constantly changing conditions of our planet. It is the ability of ecosystems to maintain balance, using the hereditary information of living organisms, that makes the biosphere as a whole and local ecosystems material-energy systems in the full sense.

In this photo we see many species of plants growing together in a meadow in the floodplain of the river. Budyumkan in the southeast of the Chita region. Why did nature need so many species in one meadow? About this and we're talking about in this lecture.

Russian geobotanist L.G. Ramensky in 1910 he formulated the principle of ecological individuality of species - a principle that is the key to understanding the role of biodiversity in the biosphere. We see that in every ecosystem many species live together at the same time, but we rarely think about the ecological meaning of this. Ecological individuality plant species living in the same plant community in the same ecosystem allows the community to quickly restructure when external conditions change. For example, in a dry summer in this ecosystem, the main role in ensuring the biological cycle is played by individuals of species A, which are more adapted to life in conditions of moisture deficiency. In a wet year, individuals of species A are not at their optimum and cannot ensure the biological cycle under changed conditions. In this year, individuals of species B begin to play the main role in ensuring the biological cycle in this ecosystem. The third year turned out to be cooler; under these conditions, neither species A nor species B can ensure the full use of the ecological potential of this ecosystem. But the ecosystem is quickly being rebuilt, since it contains individuals of species B, which do not need warm weather and photosynthesize well at low temperatures.

Each type of living organism can exist in a certain range of values external factors. Outside these values, individuals of the species die. In the diagram we see the limits of endurance (limits of tolerance) of a species according to one of the factors. Within these limits there isoptimum zone, the most favorable for the species, and two zones of oppression. Rule L.G. Ramensky about the ecological individuality of species states that the endurance limits and optimum zones of different types living together do not coincide.

In nature we find a lot of factors or mechanisms that provide and maintain high species diversity of local ecosystems. First of all, such factors include excessive reproduction and overproduction of seeds and fruits. In nature, seeds and fruits are produced hundreds and thousands of times more than is necessary to make up for the natural loss due to premature death and dying from old age.

Thanks to adaptations for dispersing fruits and seeds over long distances, the rudiments of new plants end up not only in those areas that are favorable for their growth now, but also in those whose conditions are unfavorable for the growth and development of individuals of these species. Nevertheless, these seeds germinate here, exist in a depressed state for some time and die. This happens as long as environmental conditions are stable. But if conditions change, then previously doomed to death, seedlings of species unusual for this ecosystem begin to grow and develop here, going through the full cycle of their ontogenetic (individual) development. Ecologists say that in nature there is the powerful pressure of life's diversity to all local ecosystems.

General gene pool of vegetation cover of a landscape area– its flora-local ecosystems of this area are used most fully precisely due to the pressure of biodiversity. At the same time, local ecosystems become richer in species. During their formation and restructuring, the ecological selection of suitable components is carried out from more applicants whose germs ended up in this habitat. Thus, the likelihood of the formation of an ecologically optimal plant community increases.

Thus, a factor in the stability of a local ecosystem is not only the diversity of species living in this local ecosystem, but also the diversity of species in neighboring ecosystems from which the introduction of germs (seeds and spores) is possible. This applies not only to plants that lead an attached lifestyle, but even more so to animals that can move from one local ecosystem to another. Many animal species, although not specifically belonging to any local ecosystem (biogeocoenosis), nevertheless play an important ecological role and participate in ensuring the biological cycle in several ecosystems at once. Moreover, they can alienate biomass in one local ecosystem and throw out excrement in another, stimulating the growth and development of plants in this second local ecosystem. Sometimes such transfer of matter and energy from one ecosystem to another can be extremely powerful. This flow connects completely different ecosystems.

Species diversity and diversity of life forms or ecobiomorphs are not the same thing. I will demonstrate this with this example. In a meadow there can be 2-3 times more species, genera and families of plants than in a dark coniferous forest. However, in terms of ecobiomorphs and synusia, it turns out that the biodiversity of the dark coniferous forest as an ecosystem is much higher than the biodiversity of the meadow as an ecosystem. In the meadow we have 2-3 classes of ecobiomorphs, and in the dark coniferous forest there are 8-10 classes. There are many species in the meadow, but they all belong either to the ecobiomorph class of perennial mesophytic summer-green grasses, or to the class of annual grasses, or to the class of green mosses. In the forest, different classes of ecobiomorphs are: dark coniferous trees, deciduous trees, deciduous shrubs, deciduous shrubs, perennial mesophytic summer-green grasses, green mosses, epigeic lichens, epiphytic lichens.

The biodiversity of organisms in the biosphere is not limited to the diversity of taxa and the diversity of ecobiomorphs of living organisms. For example, we may find ourselves in an area that is entirely occupied by one local elementary ecosystem - a raised bog, or a damp alder forest at the mouth of a large river. In another area, on a territory of the same size, we will encounter at least 10-15 types of local elementary ecosystems. Ecosystems of coniferous-broad-leaved forests at the bottom of river valleys are naturally replaced here by ecosystems of cedar-oak mixed-bush forests on the southern gentle slopes of the mountains, larch-oak mixed-grass forests on the northern gentle slopes of the mountains, spruce-fir forests in the upper part of the northern steep slopes of the mountains and ecosystems steppe meadows and clump vegetation on the steep southern slopes of the mountains. It's not hard to understand what it is intralandscape diversity of ecosystems determined not only by the diversity of their constituent species and ecobiomorphs, but also diversity of ecological landscape background, associated primarily with the variety of relief forms, the variety of soils and underlying rocks.

The processes of extinction of species in the biosphere are compensated by the processes of speciation. If the balance of these two processes is disrupted in favor of extinction, then the Earth will most likely suffer the fate of Venus - that is, an atmosphere of carbon dioxide and water vapor, a surface temperature of about +200 degrees Celsius, evaporated oceans and seas. Life on a protein basis under such conditions is, of course, simply impossible. Having become a powerful geological force, humanity is obliged to take responsibility not only for the future of its children and grandchildren, but also for the future of the entire biosphere. And this future will largely depend on how much the process of extinction of species in the Earth’s biosphere lags behind the process of formation of new species.

For the accounting species on the verge of extinction, Red Books are created in many countries - lists of rare and endangered species of living organisms. To preserve and maintain biological diversity, specially protected natural areas are created - protected areas (reserves, National parks etc.), genetic data banks. The preservation of an individual species is possible only under the condition of protecting its habitat with the entire complex of species included in it, climatic, geophysical and other conditions. Special role In this case, the preservation of environment-forming species (edificatory species), which form the internal environment of the ecosystem, plays a role. The creation of protected areas is aimed at protecting not only individual species, but also entire complexes and landscapes.

Reserves also serve to evaluate and monitoring state of biodiversity. There is no unified system for monitoring the state of biodiversity in Russia today. The most complete and constant monitoring of changes in biodiversity components is carried out in nature reserves. Every year, reserves prepare reports on the state of ecosystems ("Chronicles of Nature") - summaries of data on the state of protected areas, protected populations of plants and animals. Some reserves have been keeping “Chronicles of Nature” for more than 50 years, which include continuous series of data on animal numbers, biological diversity, ecosystem dynamics, and also provide data on climate observations.

Some of the Russian reserves (18) are part of the international network of biosphere reserves, specially created to monitor the state of biodiversity, climatic, biogeochemical and other processes on the scale of the Biosphere.

Reasons necessity conservation biodiversity many: the need for biological resources to meet the needs of humanity (food, materials, medicines, etc.), ethical and aesthetic aspects (life is valuable in itself), etc. However, the main reason for preserving biodiversity is that it plays a leading role in ensuring the sustainability of ecosystems and the Biosphere as a whole (absorption of pollution, climate stabilization, provision of livable conditions). Biodiversity performs a regulatory function in the implementation of all biogeochemical, climatic and other processes on Earth. Each species, no matter how insignificant it may seem, contributes to ensuring the sustainability of not only the “native” local ecosystem, but also the Biosphere as a whole.