Decrease in biodiversity under the influence of anthropogenic activities. Biodiversity

Biological diversity - variability of living organisms from all sources, including, inter alia, terrestrial, marine and other aquatic ecosystems and ecological complexes of which they are a part; it includes diversity within a species, between species and the diversity of ecosystems.

Biological diversity- the number of distinguishable types of biological objects or phenomena and the frequency of their occurrence at a fixed interval of space and time, in general case reflecting the complexity of living matter, its ability to self-regulate its functions and the possibility of its versatile use.

Biodiversity (biodiversity) - the diversity of life in all its manifestations, as well as an indicator of complexity biological system, the different quality of its components. Also, biodiversity is understood as diversity at three levels of organization: genetic diversity (diversity of genes and their variants - alleles), species diversity (diversity of species in ecosystems) and, finally, ecosystem diversity, that is, the diversity of ecosystems themselves.

The main scientific concepts of biodiversity were formulated only in the middle of the twentieth century, which is directly related to the development of quantitative methods in biology.

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History

The origin of the term "biodiversity" is debatable. It is believed that the phrase "biological diversity" was first used by G. Bates in 1892. On the other hand, it is argued that the term "BioDiversity" was first introduced by W. Rosen in 1968 at the national forum "US Biodiversity Strategy" ...

Classification

Meaning

The value of biodiversity both within the species and within the entire biosphere is recognized in biology as one of the main indicators of the viability (survivability) of the species and the ecosystem as a whole and is called the "Principle of biological diversity". Indeed, with a large uniformity of characteristics of individuals within one species (this applies to humans, plants, and microorganisms), any significant change in external conditions (weather, epidemic, change in feed, etc.) will more critically affect the survival of the species than in the case when the latter has a high degree of biological diversity. The same (at a different level) applies to the richness (biodiversity) of species in the biosphere as a whole.

The history of mankind has already accumulated whole line examples of the negative consequences of attempts at a too crude and simplistic "designation" of some biological species, families and even ecosystems as unambiguously useful, or unambiguously harmful. Drainage of swamps led not only to a decrease in malaria mosquitoes, but also to more violent spring floods when nearby fields were drained in summer, the shooting of wolves ("offenders" of deer) on a closed plateau - to an immoderate increase in the number of these deer, their almost complete extermination of food and the subsequent general case.

Biodiversity is a key concept in environmental discourse. This definition has become an official definition in terms of the letter of the law, since it was included in the UN Convention on Biodiversity, which is adopted by all countries of the Earth, with the exception of Andorra, Brunei, Vatican, Iraq, Somalia and the United States. The UN has established the International Day for Biological Diversity.

It is rather difficult to determine the need for the conservation and maintenance of biodiversity in some objective way, since it depends on the point of view of the one who assesses this need. However, there are four main reasons to conserve biodiversity:

• From the point of view of the consumer, the elements of biodiversity are natural treasures that already present visible benefits to humans today or may be useful in the future.
• As such, biodiversity provides both economic and scientific benefits (for example, in the search for new drugs or treatments).
• Choosing to conserve biodiversity is an ethical choice. Humanity as a whole is a part of the ecological system of the planet and depends on its well-being, and therefore must take good care of the biosphere.
• The importance of biodiversity can also be characterized in aesthetic, essential and ethical terms. Nature is glorified and praised by artists, poets and musicians all over the world; for man, nature is an eternal and lasting value.

Theories

Due to the fact that the field of biology studying the causes of biodiversity has not yet developed, in this area there is big number theories and individual hypotheses (over 120). The most complete overview of theories that claim to explain the patterns of change in biodiversity was presented by the famous theoretical biologist Brian McGill:

Signs and quantification

As a first approximation, biological diversity of species is characterized by two features - species richness and evenness.

Species richness reflects the number of species found within an ecosystem, while evenness characterizes the even distribution of animal numbers. The isolation of these components is due to the fact that, with rare exceptions in ecosystems, among organisms belonging to the same trophic level, ecological or taxonomic group, most of biomass is achieved through the contribution of very few species.

For quantify Inventory diversity, the measures of diversity or their dual measures of concentration are used. It is understood that the most diverse community is a “strategic reserve” of biological evolution, and, therefore, the quantitative determination of such communities allows them to ensure their conservation status. A related concept is the concept alignment (evenness or equitability) species composition community.

Another area of ​​quantitative assessment is to determine the proportion of rare and abundant species, as well as their impact on the structure of communities as a whole. A related area is the assessment of the dominance of species, within the framework of which the concept of the significance of a species is used. Significance can be understood as an assessment of its place in the ecosystem - biomass, abundance, etc.

Another (very popular and significant) direction in this area is the prediction of the number of undetected ( unseen) types of community. For these purposes, they use: simple statistical extrapolations based on methods for analyzing time series, curves of dependence of the "views-area" type, building models based on fractal patterns, etc.

Similarity measures are used to assess the differentiating diversity. In fact, the assessment of this type of diversity occurs through comparison and identification of similar elements of biosystems.

Reasons for reduction

The extinction of biological species is a normal process for the development of life on Earth. In the process of evolution, it has repeatedly happened mass extinction species. An example is the Permian extinction, which led to the extinction of all trilobites.

Since the 17th century, human economic activity has become the main factor in the acceleration of extinction; during this period, 120 species of amphibians, 94 species of birds, and 63 species of mammals disappeared. V general plan the reasons for the decline in diversity are the growing consumption of resources, neglect of species and ecosystems, insufficiently thought out public policy in the field of exploitation natural resources, lack of understanding of the importance of biological diversity and the growth of the world's population.

The reasons for the disappearance certain types habitat disturbance and over-harvesting are usually. In connection with the destruction of ecosystems, many hundreds of species of plants and animals have already died. According to the World Conservation Union, 844 species of plants and animals have disappeared since 1600. Game animals, especially those highly valued in the international market, suffer from over-prey. Rare collectible species and those illegally used in "Traditional Chinese Medicine" are under threat. Most species of large land animals (large ungulates, cats, elephants, rhinos and other animals weighing more than 20 kg) have survived only in protected areas (in nature reserves, national parks).

Other reasons include: the influence of introduced species, deterioration of the food base, targeted destruction in order to protect agriculture and fishing grounds.

According to Western scholars, in last years 33.5 thousand plant species (14% of known species) are under the threat of extinction. 2/3 of bird species out of 9.6 thousand living on Earth are experiencing a decline in numbers. 11% of all species of birds and mammals are endangered and another 14% are on the way to extinction if current trends continue. 30% of 24 thousand fish species are also endangered. Scientists from the American Duke University believe that the world in the 21st century is on the verge of the sixth extinction of plant and animal species, and human activity accelerates this process 1000 times.

Security

Basic principles of biodiversity conservation activities:

Selected aspects of biodiversity conservation

• When taking into account long-term economic interests is difficult or simply impossible, the ethical principle can be applied: "All living beings are unique in their own way and are somehow important for the biosphere as a whole and for humanity, as its particles."
• Conservation of biodiversity throughout humanity cannot be limited to protecting only a few highly species-rich ecosystems (such as rainforests or coral reefs).
• This activity should focus not only on protected natural areas(for example, reserves, habitats of certain rare species, etc.), but also areas where people live and work.
• As the priority directions of this activity, it is advisable to take reasonable measures to preserve and reasonably take into account biological diversity within humanity itself, as a biological species, and individual peoples inhabiting it. Equalizing, “average statistical” approaches to a person (when there is a possibility and social validity of taking into account the biodiversity of an individual) lead to enormous and unjustified economic, moral and environmental damage. Sick, poor and illiterate (due to such approaches) citizens simply do not have the strength and inspiration to think about the long-term environmental consequences.
• Increasing funding for biodiversity conservation will not in itself slow down the rate of extinction of species, biotopes and landscapes. A special policy of states and a whole set of transformations (in legislation, the structure of environmental activities, etc.) are needed, which will create conditions under which an increase in spending on biodiversity conservation will indeed be successful (within a given time period).
• Biodiversity conservation is the conservation of natural gifts that are important both at the local level and from the point of view of the country and all of humanity. However, the economic profitability of biodiversity conservation is noticeably manifested only when taking into account its long-term consequences and at the level big country, mainland, total the globe and the interests of their population for a long period, therefore, in order to prevent damage to biodiversity from momentary and selfish motives, it is necessary to apply appropriate restrictive (for violators) and supportive (for conscientious citizens) legislative, economic and educational measures. In other words, competent, timely and appropriate efforts to conserve biodiversity should be beneficial morally and materially and at all levels of society (from the individual, institution to the ministry and the country as a whole), while other efforts should be less or not at all beneficial.
• The conservation of biodiversity in the future can be sustainable only if the awareness and responsibility of society (at all its levels), the conviction of the need for action in this direction will constantly increase.
• It is very important that politicians and officials have both the necessary information, on the basis of which they could make informed choices and take appropriate actions, and legislative responsibility for failure to take (or untimely adoption) of relevant decisions (and, of course, prizes, awards and other public recognition - for timely and competent decisions).
• Strengthening the accountability of politicians, ministries and departments to society in their activities (including on issues of biodiversity conservation) is closely related to the expansion of legislative opportunities for responsible and competent participation and awareness of the public, volunteer societies in addressing relevant issues. Both are the most important conditions under which it is possible successful activity for the conservation of biodiversity.
• The costs that are necessary for the conservation of biodiversity, the income and profit that this activity gives or will give in the future, it is advisable to more equitably distribute between different countries and between people within individual countries... This principle implies both a high level of international cooperation, in the limit - brotherhood and mutual assistance, as well as thorough and verified legislative and scientific support (including mathematical modeling of the consequences of decisions made) to prevent both denials of assistance and support at all levels and at all issues where it is really deserved and necessary, and dependency and other possible abuse in other cases.
• Biodiversity conservation priorities differ by different levels... Local preferences may not coincide with national or human preferences, however, taking into account and, as far as possible, correctly adjusting local interests to preserve biodiversity here and now is important and essential, since any restrictive and prohibitive measures, if they significantly contradict local economic interests and customs of the population, will be so or otherwise be dispensed with and violated.
• As part of an even larger effort to achieve sustainable human development, biodiversity conservation requires fundamental changes in the approaches, composition and practice of development. economic activity worldwide.
• Cultural diversity is closely related to natural diversity. Humanity's ideas about the diversity of nature, its value and use are based on the cultural diversity of peoples, and vice versa, actions to preserve biological diversity often enhance cultural integration and increase its importance.

Biodiversity Conservation Challenges

• Economic - inclusion of biodiversity in the country's macroeconomic indicators; potential economic income from biodiversity, including: direct (medicine, raw materials and materials for breeding and pharmacy, etc.) and indirect (ecotourism), as well as costs - restoration of destroyed biodiversity.
• Managerial - creating cooperation through involvement in joint activities state and commercial institutions, army and navy, non-state associations, local population and the whole public.
• Legal - incorporating biodiversity-related definitions and concepts into all relevant legal regulations, creation of legal support for biodiversity conservation.
• Scientific - formalization of decision-making procedures, search for biodiversity indicators, compilation of biodiversity inventories, organization of monitoring.
• Environmental education - environmental education of the population, the dissemination of ideas for the protection of biodiversity, as the most important component of the Biosphere.

Year of biological diversity

On December 20, 2006, the General Assembly, by its resolution 61/203, proclaimed 2010 the International Year of Biodiversity.

On 19 December 2008, the Assembly called on all Member States to fulfill their commitments to significantly reduce the rate of biodiversity loss by 2010, by giving appropriate attention to this issue in their respective policies and programs (resolution 63/219). The Assembly invited all Member States to create International Year biodiversity national committees, including representatives of indigenous peoples and local communities, and invited all international organizations to celebrate this event as well.

In support of the International Year of Biodiversity, the Assembly planned to hold a one-day high-level meeting in 2010, during its sixty-fifth session, with the participation of Heads of State, Government and Delegation.

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Notes (edit)

1. Convention on Biological Diversity(Russian). Retrieved May 5, 2010. Archived August 28, 2011.
2. Ecological Dictionary, 2001(Russian). Retrieved 5 July 2015.
3. Lebedeva N.V., Drozdov N.N., Krivolutsky D.A. Biodiversity and methods for its assessment. - M .: MGU, 1999 .-- 94 p.
4. Bates G.W. Naturalist on the Amazon River: a story about tropical pictures of nature, about the customs of animals, about the life of the Brazilians and Indians, and about the travel adventures of the author during his eleven years of wanderings. - M .: Geografgiz, 1958 .-- 430 p.
5. A.V. Adrianov Contemporary problems study of marine biological diversity // Biology of the sea. 2004. Vol.30. No. 1. S. 3-19.
6. Whittaker R.H. Vegetation of the Siskiyou Mountains, Oregon and California // Ecol. Monogr. 1960. No. 30. P. 279-338.
7. Whittaker R.H. Evolution and measurement of species diversity // Taxon. 1972. No. 2. P. 213-251.
8. Whittaker R.H. Communities and ecosystems. - N.-Y .: London: Macmillan., 1970. - 162 p.
9. Geography and monitoring of biodiversity // Coll. authors. - M .: Scientific and scientific-methodical center, 2002. - 432 p.
10. Palmer, M. W. Variation in species richness: Towards a unification of hypotheses // Folia geobot. phytotax. 1994. Vol. 29. P. 511-530. doi: http: //www.jstor.org/stable/4181308
11. McGill B. J. Towards a unification of unified theories of biodiversity // Ecology Letters. 2010. No. 13 (5). P. 627-642.
12. Initial data taken from publication V.D. Zakharov. Species diversity of the bird population of the Taganai National Park (Russian) // News of the Chelyabinsk Scientific Center of the Ural Branch of the Russian Academy of Sciences. - 2005. - Issue. 1 . - S. 111-114.

Biological diversity (BR) is the totality of all life forms that inhabit our planet. This is what makes the Earth different from other planets. Solar system... BR is the wealth and diversity of life and its processes, including the diversity of living organisms and their genetic differences, as well as the diversity of their places of existence. BR is divided into three hierarchical categories: diversity among representatives of the same species (genetic diversity), between different species and between ecosystems. Research of global BR problems at the gene level is a matter of the future.

Most authoritative rating species diversity completed at UNEP in 1995. According to this estimate, the most probable number of species is 13-14 million, of which only 1.75 million are described, or less than 13%. The highest hierarchical level of biological diversity is ecosystem, or landscape. At this level, the patterns of biological diversity are determined primarily by zonal landscape conditions, then local characteristics natural conditions (relief, soil, climate), as well as the history of the development of these territories. They are distinguished by the greatest species diversity (in descending order): humid equatorial forests, coral reefs, dry tropical forests, moist forests temperate zone, oceanic islands, landscapes Mediterranean climate, treeless (savanna, steppe) landscapes.

In the past two decades, biological diversity has begun to attract the attention of not only biologists, but also economists, politicians, and the public in connection with the obvious threat of anthropogenic degradation of biodiversity, far exceeding normal, natural degradation.

According to UNEP's Global Biodiversity Assessment (1995), more than 30,000 animal and plant species are at risk of destruction. Over the past 400 years, 484 animal species and 654 plant species have disappeared.

Reasons for the current accelerated decline in biological diversity-

1) rapid population growth and economic development, making huge changes in the living conditions of all organisms and ecological systems Earth;

2) increased migration of people, growth of international trade and tourism;

3) increasing pollution of natural waters, soil and air;

4) insufficient attention to the long-term consequences of actions that destroy the conditions for the existence of living organisms, exploiting natural resources and introducing non-native species;

5) impossibility in conditions market economy estimate the true value of biological diversity and its losses.

Over the past 400 years, the main immediate causes the extinction of animal species were:

1) the introduction of new species, accompanied by the displacement or extermination of local species (39% of all lost animal species);

2) destruction of living conditions, direct withdrawal of territories inhabited by animals, and their degradation, fragmentation, increased marginal effect (36% of all lost species);

3) uncontrolled hunting (23%);

4) Other reasons (2%).

The main reasons for the need to preserve genetic diversity.

All species (no matter how harmful or unpleasant they may be) have a right to exist. This provision is recorded in the "World Charter for Nature", adopted The General Assembly UN. Enjoyment of nature, its beauty and diversity is of the highest value, not expressed in quantitative terms. Diversity is the basis for the evolution of life forms. Declining species and genetic diversity undermines the further improvement of life on Earth.

The economic feasibility of biodiversity conservation is due to the use of wild biota to meet the various needs of society in industry, agriculture, recreation, science and education: for the breeding of domestic plants and animals, the genetic reservoir necessary to renew and maintain the resistance of varieties, the manufacture of medicines, as well as for providing the population with food, fuel, energy, timber, etc.

There are many ways to protect biological diversity. At the species level, there are two main strategic directions: in-situ and out-of-habitat. Protecting biodiversity at the species level is an expensive and laborious path, possible only for a select few species, but unattainable for protecting all the richness of life on Earth. The main thrust of the strategy should be at the ecosystem level, so that the systematic management of ecosystems ensures the protection of biological diversity at all three hierarchical levels.
The most effective and relatively economical way to protect biological diversity at the ecosystem level is protected areas.

In accordance with the classification of the World Conservation Union, there are 8 types of protected areas:

1. Reserve. The goal is to preserve nature and natural processes in an undisturbed state.

2. National Park. Purpose - preservation natural areas national and international importance for scientific research, education and recreation. Usually these are large territories in which the use of natural resources and other material human influences are not allowed.

3. Monument of nature. These are usually small areas.
4. Managed natural reserves. The collection of certain natural resources is permitted under the supervision of the administration.

5. Protected landscapes and seaside views. This is a picturesque mixed natural and cultivated area with the preservation of traditional land use.
Protected area statistics usually include land in categories 1-5.

6.Resource reserve created to prevent premature use of the territory.

7. Anthropological reserve, created to preserve the traditional way of life of the indigenous population.

8.Territory for the multipurpose use of natural resources, focused on the sustainable use of water, forest, animal and flora, pastures and for tourism.
There are two additional categories that overlap the eight above.

9. Biosphere reserves. Created with the aim of preserving biological diversity. They include several concentric zones of varying degrees of use: from a zone of complete inaccessibility (usually in the central part of the reserve) to a zone of reasonable, but rather intensive exploitation.

10 places world heritage... Created to protect unique natural features of global importance. Management is carried out in accordance with the World Heritage Convention.

In total, there are about 10,000 protected areas (categories 1-5) in the world with a total area of ​​9.6 million km, or 7.1% of total area sushi (no glaciers). The goal that the World Conservation Union sets for the world community is to achieve the expansion of protected areas to the size of 10% of the area of ​​each large plant formation (biome) and, consequently, the world as a whole. This would contribute not only to the protection of biodiversity, but also to increase the resilience of the geographic environment in general.

The strategy of expanding the number and extent of protected areas is in conflict with the use of land for other purposes, especially in view of the growing population of the world. Therefore, for the protection of biological diversity, it is necessary, along with protected areas, to increasingly improve the use of "usual", inhabited, lands and population management. wild species, and not only endangered ones, and their habitats on such lands. It is necessary to apply such techniques as the zoning of territories according to the degree of use, the creation of corridors connecting land masses with less anthropogenic pressure, reducing the degree of fragmentation of biodiversity hotspots, managing ecotones, preserving natural waterlogged lands, managing populations of wild species and their habitats.

TO effective ways the protection of biological diversity includes the bioregional management of significant areas and water areas, as well as international agreements on this issue. United Nations Conference on environment and Development (1992) adopted the International Convention for the Protection of Biological Diversity.

An important agreement is the Convention on International Trade in Species wild fauna and flora under threat of destruction. There are also a number of other conventions that protect various aspects biological resources and biodiversity: the Convention on the Conservation of Migratory Species of Wild Animals, the Convention on the Conservation of Wetlands, the Convention on the Protection of Whales, etc. Along with the global conventions, there are numerous regional and bilateral agreements regulating specific issues of biodiversity.

Unfortunately, so far it can be stated that, despite numerous measures, the accelerated erosion of the world's biological diversity continues. However, without these safeguards, the rate of loss of biodiversity would be even greater.

Changes in species diversity can affect the basic processes in ecosystems - production and decay organic matter on a scale comparable to the impact of global factors. Analysis of the results of many individual experiments made it possible to calculate the change in the average values ​​of primary production in ecosystems with a change in the species richness in them. It turned out that the production process in ecosystems depends on species diversity more strongly than the processes of destruction of organic matter. With a decrease in the number of species by half, the production of ecosystems decreases by an average of 13%. The influence of diversity on the process of decomposition of organic matter is less obvious - a decrease in diversity can lead to both a slowdown and an acceleration of the processes of destruction in ecosystems.

How does species diversity affect the fundamental properties of ecosystems? This question is important both for understanding the general laws of ecology and for solving practical problems. Reducing the resilience of artificial communities with a small number of species is used as one of the main arguments in defense of wildlife, in favor of the creation of nature reserves and sanctuaries.

The relationship of the species diversity of ecosystems with their functional characteristics- sustainability and productivity - is accepted by the majority of ecologists. Private research on individual communities confirms the existence of such links. Remains open question: How common are these patterns?

In theoretical ecology last decade an increasingly important role is played by meta-analysis - the identification of patterns that are repeated in different natural conditions for different groups organisms or different types ecosystems and communities. For this, databases are created that include the results of the same type of experiments or observations carried out in various ecosystems in different parts the world, on land, at sea and in freshwater bodies.

A group of researchers (Hooper et all., 2012) set the task to assess how species diversity affects the fundamental properties of any ecosystem - the production and decomposition of organic matter. As a result of photosynthesis reactions, green plants create organic matter from inorganic compounds, which all other organisms, from fungi and bacteria to birds and mammals, use for food. Green plant production (usually expressed in grams per square meter per unit time) is the most important indicator of the energy efficiency of the ecosystem together with the reverse process - the decomposition of organic matter, in which all other members of the community participate.

To do this, they used a database containing the results of 574 separate experiments on the change in the productivity of plant communities with a decrease in the number of species included in them (in the limit - to monoculture, that is, crops of one species). The second data set was used to test the hypothesis about the change in the rate of destruction (decomposition of organic matter) depending on the species diversity. This hypothesis was tested in two versions - a change in the rate of destruction with a decrease in the number of destructor species and a change in the rate of destruction of fallen leaves, depending on the diversity of plant species to which they belong.

As a measure of assessment, we used the logarithms of the ratio of the value of production or destruction for a given number of species (Y S) to the same value for the maximum possible number of species in a community of this type (Y max): ln (Y s / Y max). Positive values ​​of this indicator mean an increase in production or destruction with a decrease in species diversity, negative - a decrease.

For comparison, in order to assess the scale of changes occurring with a decrease in the species diversity of communities, the authors provide estimates of the impact of other global factors on the production process. To do this, they use databases containing the results of observations and experiments on the impact of factors such as climate change (including droughts), an increase in the concentration of carbon dioxide, an increase in the concentration of nitrogen, phosphorus and other nutrients available to plants in water and soil, an increase in the acidity of the environment and others. The number of observations in each of the bases ranges from several hundred to thousands. Data include observations and experiments in terrestrial, freshwater and marine environments.

Experiments have shown that a moderate (by 21–40%) decrease in species diversity leads to a decrease in the primary production of plants by 5–10%. A twofold decrease in species diversity leads to a decrease in the primary production of ecosystems by an average of 13%.

Higher levels (decrease in diversity by 41–60% from the initial) in terms of influence on the production process are comparable to the effects of such global factors as eutrophication, increased acidity or an increase in carbon dioxide concentration.

The results of assessing the influence of diversity on the destruction process turned out to be less clear. A decrease in diversity in communities of plant consumers to half of the initial value does not lead to a noticeable change. With a further depletion of the composition of destructors, the rate of decomposition of plant residues decreases by about 20%.

The diversity of the composition of plant residues (the number of plant species whose leaves were subjected to decomposition in the experiment) practically does not affect the rate of the destruction process. Only at very low values ​​of diversity is an insignificant and not quite reliable increase in the rate of decomposition of leaf litter observed.

This study is of interest as an example of multiple meta-analysis - an attempt to generalize a large number of dissimilar experiments in search of common patterns, which is always very difficult in environmental studies, where each object has its own personality.

On the other hand, the authors convincingly (at least in relation to the production process) showed that a decrease in species diversity in ecosystems can act as an independently acting factor, in terms of the level of influence on key parameters comparable to other global factors of transformation of the natural environment.

Biodiversity or biological diversity is a term that describes the diversity of living organisms on Earth and the degree to which life has changed. Biodiversity includes microorganisms, plants, animals and such as coral reefs, etc. Biodiversity is everything from towering trees to tiny unicellular algae that cannot be seen without a microscope.

It also refers to the number or abundance of different species found in a given region. Biodiversity represents the wealth available to us. It is about maintaining natural areas made up of communities of plants, animals and other living things that are altered or become extinct due to anthropogenic impact, and destruction.

Elements and distribution

In biodiversity, every species, no matter how large or small, plays important role... Different types of plants and animals depend on each other, and these various types provide natural resilience to all life forms. Healthy and resilient biodiversity can recover from a variety of disasters.

Biodiversity has three main elements:

• Ecological diversity;
• Species diversity;

Recently, a new element has been added - "molecular diversity".

Biodiversity is unevenly distributed. It varies globally and regionally. Various factors affecting biodiversity include: temperature, altitude, precipitation, soils and their relationship to other species. For example, ocean biodiversity is 25 times less than terrestrial diversity.

Biodiversity is the result of over 3.5 billion years. It has undergone various periods. The last and most destructive stage of extinction is the Holocene extinction (era), which was partially influenced by human activities.

The role of biological diversity

All types are interconnected and dependent on each other. Forests provide homes for animals. Animals eat plants. Plants need healthy soil to grow. Mushrooms help break down organisms to fertilize the soil. Bees and other insects carry pollen from one plant to another, which allows the flora to reproduce. With less biodiversity, these relationships are weakened and sometimes destroyed, harming all species in the ecosystem.

Biodiversity has a number of functions on Earth, including:

• Maintaining a balance of ecosystems: processing and storage of nutrients, combating, stabilizing the climate, protecting, forming and protecting the soil, and maintaining environmental friendliness.
• Biological resources: provision of medicines and pharmaceuticals, food for the population and animals, ornamental plants, wood products, breeding stock, species diversity, ecosystems and genes.
• Social benefits: recreation and tourism, cultural value, education and research.

The role of biodiversity in the following areas will help to clearly define its importance in human life:

• Food: about 80% of the human food supply comes from 20 plant species. But humans use about 40,000 species of flora for food, clothing and shelter. Biodiversity provides the population of our planet with food.
• Human health: shortage is expected drinking water will create a serious global crisis. Biodiversity also plays an important role in drug discovery. Most of the world's population uses natural medicines.
• Industry: biological sources provide a variety of industrial materials. These include fiber, oil, dyes, rubber, water, wood, paper, and food.
• Culture: biodiversity provides recreational activities such as bird watching, fishing, hiking, etc. It inspires musicians, poets and artists.

Biodiversity types

The main way to measure biodiversity is by counting the total number of species that live in a given area. Tropical areas where warm climatic conditions all year round, have the greatest biological diversity. In temperate regions where warm summers give way cold winter, there is less biodiversity. Regions with cold or dry conditions, such as deserts, have even less biodiversity.

Generally, the closer a region is to the equator, the greater the biodiversity. At least 40,000 different plant species are found in the Amazon in South America, one of the most biologically diverse regions of the planet.

Warm waters of the western part of the Pacific and Indian oceans are the most diverse marine habitats. Indonesia is home to over 1200 species of fish and 600 species of coral. Many corals create, which are home to hundreds of species of organisms, from tiny seaweed to large sharks.

In some regions of the world there is a large number of(species that exist only in a certain area). In the Cape region - a natural ecosystem South Africa- there are about 6200 plant species that are not found anywhere else in the world. Areas with a large number of endemic species are called biodiversity hotspots. Scientists and organizations are making special efforts to save life in these regions.

Biodiversity can also refer to the diversity of ecosystems — communities of living things and theirs. Ecosystems include deserts, grasslands, and rainforests. Africa has tropical rain forests, alpine mountains and dry deserts. The mainland has high level biodiversity, and Antarctica, almost completely covered with ice, is low.

Genetic diversity is another way to measure biodiversity. Genes are the main units of biological information transmitted by living things. Some species have up to 400,000 genes. (Humans have about 25,000 genes, while rice has more than 56,000.) Some of these genes are the same for all individuals within a species — they make chamomile a chamomile and a dog a dog. But some genes are different within a species, so, for example, some dogs are poodles and others are pit bulls. This is why some people Brown eyes and others are blue.

Wider genetic diversity in species can make plants and animals more resistant to disease. Genetic diversity also allows species to better adapt to changing environments.

Decrease in biodiversity

Over the past hundred years, biodiversity around the world has declined dramatically. Many species have become extinct. Extinction is a natural process; some types naturally die out, and new species evolve. But human activity has changed natural processes disappearance and evolution. Scientists estimate that species are now dying out hundreds of times faster than evolution requires.

The main cause of biodiversity loss is the destruction of natural habitats. Fields, forests and wetlands where they live wild plants and the animals disappear. People clear land to plant crops, build houses and businesses. Forests are cut down to obtain timber.

As habitats shrink, they can support fewer living organisms. The surviving creatures have fewer partners to reproduce, so genetic diversity is reduced.

Global climate change is also a factor reducing biodiversity around the world. Warmer ocean temperatures damage fragile ecosystems like coral reefs. One coral reef capable of supporting the life of 3000 species of fish and others sea ​​creatures such as shellfish and starfish.

Invasive species can also affect biodiversity. When humans introduce species from one part of the world to another, they often lack natural predators. These "non-native" organisms thrive in their new habitat and often destroy native species.

People around the world are working to conserve biodiversity. Animals and plants are the most famous endangered organisms. Thousands of protected areas have been created on our planet to protect plants, animals and ecosystems. Local, national and international organizations cooperate to conserve the biological diversity of regions threatened by development or natural disasters. People are also working to limit pollution and restore ecosystems. As ecosystems become healthier, their biodiversity increases.

Most of those who periodically think about the dangers that lie in wait for the natural world tend to think of danger as something that threatens other creatures. Declining populations of exotic animals such as pandas, tigers, elephants, whales, and different kinds birds draw attention to the problem of the species at risk. The rate of extinction of species is 50-100 times higher than natural and, as it is assumed, they will only increase sharply. Taking into account the current global trends, almost 34,000 species of flora and 5,200 species of fauna are threatened with extinction, including the extinction of every eighth bird species. For thousands of years we have been breeding huge number pets and cultivated plants occupying an important place in our food chain. However, this treasure is dwindling as the modern Agriculture focuses on a relatively small number of cereal varieties.

Also, almost 30% of the main breeds of farm animals are currently under threat of extinction. Of course, the disappearance of certain species attracts our attention, but real threat The loss of biodiversity is brought about by processes such as fragmentation, degradation, deforestation, drainage of wetlands, the death of corals and other ecosystems. Forests are home to most of the planet's known terrestrial ecosystems, but little more than 55 percent of the original forest cover remains on Earth, and has largely been removed in the last century. Despite ongoing reforestation efforts, the world's forest cover continues to decline rapidly, especially in tropical regions.

Almost 10 percent of coral reefs, classified as the richest ecosystems, have been destroyed, and a third of the remaining are threatened with extinction in the next 10-20 years. Areas of coastal mangrove forests, vital nurseries for countless flora and fauna, are also endangered, with half of them already irrevocably lost.

Global changes in the atmosphere, such as ozone depletion, and only add to the problem. A thinner ozone layer increases the penetration of biologically active ultraviolet radiation to the Earth's surface, where it affects living tissue... Global warming is already having its detrimental effects on habitat changes and changes in species migration trends. Scientists warn that a sharp increase in the average global temperature of even one degree will put many species on the brink of extinction. Our food production systems can also be severely affected.

Loss of biodiversity often reduces the productivity of ecosystems, thereby depleting the natural storehouse of goods and services that we constantly use. It destabilizes ecosystems and weakens their ability to withstand natural disasters such as floods, droughts and hurricanes, as well as anthropogenic stresses such as pollution and climate change. We are already spending huge sums of money to deal with floods and hurricanes exacerbated by deforestation, and this amount will only increase with global warming.

The loss of biodiversity and its impact on our lives is reflected in the most different forms... The originality of our culture is rooted deep in the surrounding us biological environment... Plants and animals are symbols of our world, represented on flags, sculptures and other images that define us and our society. One kind of beauty and power natural phenomena inspires us to create masterpieces. Although the extinction process has always been considered a natural phenomenon, the rate of extinction is accelerating dramatically as a result human activity... There is a fragmentation or disappearance of individual ecosystems, an incalculable number of species are on the verge of extinction or have already become extinct. We are on the cusp of the greatest crisis we have created that will lead to the extinction of more species than disaster, as a result of which the dinosaurs became extinct 65 million years ago. The extinction process is irreversible and given our dependence on cereals, medicinal plants and other biological resources is a threat to our well-being. It is imprudent, if not downright dangerous, to constantly undermine the foundations of your own life support system. To say the least, it is unethical to drive the matter to the complete extinction of species, thereby depriving present and future generations of options for survival and development.

Can we save ecosystems at the global level, and together with them not only species that are valuable to us, but also millions of other species that may become sources of food and medicine for future generations? The answer lies in our ability to moderate our appetites by aligning them with nature's ability to produce what we need and absorb what we throw away.