The borders of the continent Europe. Western Europe

Ecosystem - This is the functional unity of living organisms and their habitat. The main characteristic features of the ecosystem are its dimensionlessness and perseglessness. The substitution of some biocenoses by others for a long period of time is called Sukessia. Sukzesia, which occurs in the newly formed substrate, is called primary. Sukcessia in the territory already occupied by vegetation is called secondary.

The unit classification of ecosystems is a biome - a natural zone or area with defined climatic conditions and a corresponding set of dominant plant and animal species.

Special ecosystem - biogeocenosis - section of the earth's surface with homogeneous natural phenomena. Composite parts of biogerocenosis are climatop, edafotop, hydrotop (biotop), as well as phytocenosis, zoecenosis and microbocenosis (biocenosis).

In order to obtain food products, a person artificially creates agroecosystems. They differ from naturally low stability and stability, but higher productivity.

Ecosystems - Basic Structural Units of the Biosphere

Ecological system, or ecosystem, is the main functional unit in ecology, as it includes organisms and

non-fat Wednesday components, mutually affecting each other's properties, and the necessary conditions for maintaining life in that form that exists on Earth. Term ecosystem first was proposed in 1935 by the English ecologist A. Tensley.

Thus, under the ecosystem is a combination of living organisms (communities) and their habitats that form due to the cycle of substances, a steady system of life.

Communities of organisms are associated with an inorganic medium with close material and energy connections. Plants can only exist due to the constant flow of carbon dioxide, water, oxygen, mineral salts in them. Heterotrophs live at the expense of autotrophic, but need to have inorganic compounds such as oxygen and water.

In any particular place of habitat of the inorganic compounds necessary to maintain the vital activity of those inhabited by its organisms, would have enough for a short time if these reserves were not renewed. The return of biogenic elements on Wednesday occurs both during the lives of organisms (as a result of breathing, excretion, defecation) and after their death, as a result of the decomposition of corpses and plant residues.

Consequently, the community forms a certain system with an inorganic medium in which the flow of atoms caused by the vital activity of organisms has a tendency to closes into a circulation.

Fig. 8.1. Biogeocenosis structure and interaction scheme between components

In the domestic literature, the term "biogeocenosis" proposed in 1940 B.. N.Sukachev. According to it, biogeocenosis is "a collection of homogeneous natural phenomenon (atmospheric, rock, soil and hydrological conditions known arousal, having a particular specificity of the interactions of these components and a certain type of metabolism and the energy of them among themselves and other phenomena of nature and representing internally contradictory dialectical unity in permanent motion, Development. "

In Biogeocenosis V.N. Sukachev highlights two blocks: Ecotop. - Set of conditions abiotic environment and biocenosis - A combination of all living organisms (Fig. 8.1). Ecootope is often considered as an abiotic medium, not transformed by plants (primary complex of factors of the physico-geographical medium), and biotope - as a set of elements of the abiotic medium, modified by the media-forming activities of living organisms.

It is believed that the term "biogeocenosis" significantly reflects structural characteristics The macrosystem studied, whereas the concept of "ecosystem" is investing, first of all, its functional essence. In fact, there is no difference between these terms.

It should be indicated that the combination of a specific physico-chiotic environment (biotope) with the community of living organisms (biocenosis) and forms an ecosystem:

Ecosystem \u003d biotope + biocenosis.

Equilibrium (stable) state of the ecosystem is provided on the basis of cycling of substances (see paragraph 1.5). All components of the ecosystems are directly involved in these cyphans.

To maintain the cycle of substances in the ecosystem requires a stock inorganic substances In the digestible form and three functionally different environmental groups of organisms: producers, consumers and renders.

Producents Avtotrophic organisms are capable of building their bodies due to inorganic compounds (Fig. 8.2).

Fig. 8.2. Products

Consumes - Heterotrophic organisms consuming organic matter producers or other consumers and transform it into new forms.

Roducenie Live at the expense of a dead organic matter, translating it again in inorganic compounds. Classification This relative, since consversions, and the producers themselves are partly in the role of the reasons during the life, allocating mineral substances in the environment.

In principle, the cycle of atoms can be maintained in the system and without intermediate links, due to the activities of the two other groups. However, such ecosystems are found more like exceptions, for example, in those areas where communities are functioned only from microorganisms. The role of consumers is carried out in nature mainly animals, their activities to maintain and accelerate cyclic migration of atoms in ecosystems are complex and diverse.

The scale of the ecosystem in nature is quite different. Nonodynakiac Also, the degree of closerness of the substance supported in them, i.e. The multipleness of the involvement of the same elements in the cycles. As a separate ecosystems, you can consider, for example, a pillow of lichens on the trunk of a tree, and a collapsing stump with its population, and a small temporary water, meadow, forest, steppe, desert, the whole ocean and, finally, the entire surface of the earth, occupied by life.

In some types of ecosystems, the removal of a substance beyond their limits is so large that their stability is mainly maintained due to the influx of the same amount of the substance from the outside, while the inner circulation is inoperate. Such are the flowing reservoirs, rivers, streams, plots on the steep slopes of the mountains. Other ecosystems have a significantly more complete cycle of substances and relatively autonomous (forest, meadows, lakes, etc.).

Ecosystem is a practically closed system. This is the principal difference between ecosystems from communities and populations, which are open systems, exchanging with the habitat with energy, substance and information.

However, no earth ecosystem has a completely closed cycle, since the minimum exchange of mass with the habitat is still happening.

The ecosystem is a set of interconnected energy consumers who work to maintain its nonequilibrium state relative to the habitat through the use of solar energy.

In accordance with the hierarchy of the community, life on Earth is also manifested in the hierarchy of the respective ecosystems. Ecosystem organization of life is one of the necessary conditions for its existence. As already noted, the stocks of the biogenic elements necessary for the lives of organisms on the ground as a whole and on each particular area on its surface are not limited. Only the cycle system could give these reserves the infinity property necessary to continue their lives.

Maintain and carry out a circulation can only functionally different groups of organisms. The functional-ecological diversity of living beings and the organization of flows extracted from the environment of substances into cycles is ancient property of life.

From this point of view, the sustainable existence of many species in the ecosystem is achieved through the natural violations of habitats that allow new generations to occupy the newly liberated space.

Ecosystem concept

The main object of the study of ecology is environmental systems, or ecosystems. The ecosystem occupies the following place in the system of wildlife levels after biocenosis. Speaking of biocenosis, we had in mind only living organisms. If we consider living organisms (biocenosis) in aggregate with environmental factors, then this is an ecosystem. Thus, the ecosystem is a natural complex (biocosna system) formed by alive organisms (biocenosis) and their habitat (for example, the atmosphere is of oblique, soil, reservoir - biocosna, etc.) related to the exchange of substances and energy.

The term "ecosystem" was generally accepted in the ecology introduced in 1935. English Botanist A. Tensley. He believed that the ecosystems, "from the point of view of the ecologist, represent the main natural units on the surface of the Earth," which includes "not only a complex of organisms, but also the whole complex of physical factors forming what we call the bioma environment - habitat factors in The broadest sense. " Tensley emphasized that the ecosystems are characterized by various types of metabolism not only between organisms, but also between organic and inorganic substance. This is not only a complex of living organisms, but also a combination of physical factors.

Ecosystem (Environmental System) - The main functional unit of ecology, which is the unity of living organisms and their habitat, organized by energy flows and the biological cycle of substances. This is the fundamental community of living and environment of its habitat, any aggregate of joint living organisms and conditions of their existence (Fig. 8).

Fig. 8. Various ecosystems: A - pond of the middle strip (1 - phytoplankton; 2 - zooplankton; 3 - boobs-boards (larvae and adults); 4- young carps; 5 - pikes; 6 - Larvae Khoronade (mosquito dergunsov); 7- bacteria; 8 - insects of coastal vegetation; b - meadows (I - abiotic substances, i.e. basic inorganic and organic terms); II- production (vegetation); III- Macroconsters (animals): a - herbivores (kills, Field mice, etc.); in - indirect or feeding consumers, or saprobes (soil invertebrates); C- "High" predators (hawks); IV-Emplifiers (putrefactive bacteria and mushrooms)

The concept of "ecosystem" can be applied to objects of varying degrees of complexity and magnitude. An example of an ecosystem can serve as a rainforest in a certain place and at a particular point in time, inhabited by thousands of types of plants, animals and microbes living together and related interactions between them. Ecosystems are natural education such as the ocean, sea, lake, meadow, swamp. The ecosystem may be a bog in a swamp and a rotting tree in the forest with the living on them and in them with organisms, an anthill with ants. The biggest ecosystem is the planet Earth.

Each ecosystem can be characterized by certain boundaries (fir forest ecosystem, low-swamp ecosystem). However, the very concept of "ecosystem" is unreamed. It has a sign of dimensionlessness, it is not characteristic of territorial restrictions. Typically, ecosystems are separated by elements of a abiotic medium, such as relief, species diversity, physicochemical and trophic conditions, etc. The size of ecosystems cannot be expressed in physical units Measurements (area, length, volume, etc.). It is expressed by a systemic measure that takes into account the metabolic processes and energy. Therefore, under the ecosystem usually understand the combination of components of biotic (living organisms) and the abiotic medium, when the interaction of which occurs more or less complete biotic circulation, which involves producers, consvers and relegates. The term "ecosystem" is used in relation to artificial formations, such as the Ecosystem of the Park, Agricultural Ecosystem (Agroecosystem).

Ecosystems can be divided into Microshosystems (tree in the forest, coastal thickets of aquatic plants), Mesoecosystems(swamp, pine forest, rye field) and Macroecosystems (Ocean, sea, desert).

About equilibrium in ecosystems

Equilibriums are the same ecosystems that "control" biogen concentrations, maintaining their equilibrium with solid phases. The solid phases (residues of living organisms) are biota vital products. The equilibrium will be the communities and populations, which are included in the equilibrium ecosystem. This type of biological equilibrium is called MovableSince the fusion processes are continuously compensated by the appearance of new organisms.

Equilibrium ecosystems obey the principle of sustainability le chateel. Consequently, these ecosystems have homeostacre, in other words, can minimize the external effect while maintaining internal equilibrium. Ecosystem stability is achieved not by displacement chemical equilibria, but by changing the rates of synthesis and decomposition of biogen.

Of particular interest is the method of maintaining the stability of ecosystems based on the involvement of organic substances in the biological cycle of organic substances, a previously produced ecosystem and deferred "about the supply" - wood and mortmasses (peat, humus, bedding). In this case, wood serves as individual material wealth, and Mortmasse - collective, belonging to the ecosystem as a whole. This "material wealth" increases the supply of ecosystem resistance, ensuring their survival with adverse climate change, natural disasters, etc.

The stability of the ecosystem is the greater, the more it is in size and the richer and more diverse its species and population composition.

Ecosystems of different types There are various options for individual and collective methods of stability in various ratios of individual and collective material wealth.

Thus, the main function of the aggregate of living beings (community) included in the ecosystem is to ensure an equilibrium (sustainable) state of the ecosystem based on a closed cycle of substances.

If you talk about mushrooms, the first thing that comes to the head is the autumn forest, quiet hunting. You can still remember the yeast, cheese with mold and penicillin. But about what role mushrooms play in the ecosystem, why are they needed by nature, few people are thinking. Let's talk about it.

Harm or benefit?

It is said that if we put the benefit on one scale, which a person receives from these organisms, and the other is their harm, the bowls are balanced. Although, arguing about what role mushrooms play in the ecosystem, it is impossible to raise the question. Nature is important and necessary.

Science Mycology is considered one of the sections of Botany. But the mushrooms have long been highlighted in a separate kingdom. That is, there is also separate - the kingdom of mushrooms.

One of the main features is that the structural carbohydrate in the cell wall of these organisms is chitin. It is also an integral part of the outer skeleton of insects, arthropods. Hitin has interesting properties, one of which is the ability to remove harmful substances from the human body, reduce cholesterol content. At the same time, because of it, mushrooms are considered severe food. For up to 6-7 years old, they are better not to give them, nursing mothers are also better not to eat them. The enzyme system of the child may not cope with this product.

Why do Nature need mushrooms?

One of the main functions is the decomposition, processing of organic residues. As a result of the biodegradation of dead vegetable and animal organisms, carbon and mineral substances are returned to the natural circulation.

Mushrooms are involved in the process of soil formation, affect their structure, composition and even temperature regime. After all, the temperature of decaying residues increases with rotting. It is well known to robes growing vegetables on warm beds.

Mushrooms in the process of their livelihoods create biomass from mycelium and fruit bodies (the fact that since childhood we know as amansoras, raw materials, stabberry, etc.). They feed not only people, but also insects and various animals.

Mribocornia

The value of mushrooms in the creation of mycorrhiza is invaluable. It turns out that mushrooms not only destroy the trees, but can be useful for them. In nature, the phenomenon of symbiosis - beneficial for both organisms of coexistence is widespread.

Mikoriza forms an association from the threads of mycelium and the roots of trees. The mushroom receives nutrients from the highest plant in an affordable form and, in turn, helps it to produce water and phosphorus from the soil. The wood actually appears additional roots.

Mycorrise can be an external surrounding root, and can also penetrate inside. There are active metabolism between cells of two organisms. What role are mushrooms play in the ecosystem in this case? The life of the forest is simply impossible without them, especially in arid areas.

On the verge of survival

In places where the climate of harshs and vegetation is very scarce, mushrooms form symbiotic communities not with trees, but with algae, known as lichen. They can be found in the tundra and the desert, on the rocks, buildings, the crust of trees - where, there would seem, there is no condition for the life. But the mushrooms produce water even from the air, from dew, and algae converts carbon dioxide into the organic food for both.

Enhancing new spaces, working in these places of the organicists - this is another value of mushrooms in nature.

Mushroom predators

In terms of lifestyle and method of food, mushrooms are divided into:

On the null pouches Coprofili mushrooms live, carboophiles.

And some mushrooms are able to "hunt." Their prey can be amcribes, insects, nematodes. The threads of the fungus stick to the victim, envelop with mucus, some are even able to strangle it, then germinate inside and eat it. This is another example of what role mushrooms play in the ecosystem.

Huge and multicolored

The world's visible mushrooms is a tiny part of the existing variety of their species. Mushrooms, photos and names of which are familiar from childhood, is an amicer, white, oen, cheerful, and many others. They are in children's collaving and culinary books, reference books on emergency medicine and pharmacology textbooks. Mushrooms for humans can be exquisite food and fatal poison, are able to treat and cause diseases, save and destroy the harvest, make unsuitable accommodation.

The era of antibiotics began with mushrooms in medicine. Now more and more evidence is used to raise immunity, the fight against cancer Cordyceps, Shiitake, etc.

These are our visible and invisible, necessary and dangerous neighbors.

The ecosystem includes living organisms (their totality is called biocenosis, or bioto ecosystems), non-residential factors (abiotic) - atmosphere, water, nutritional elements, light and dead organic matter - detritus.

All living organisms on the method of nutrition (according to the functional role) are divided into two groups - avtotrophov (from the Greek words of Outos - himself and tropho - meals) and Heterotrofov (From the Greek word heteros - another).

Avtotropy.. These organisms for the synthesis of organic matter use inorganic carbon, this is - products Ecosystems. According to the energy source used, they, in turn, are also divided into two groups.

Photo AutoTographicuse light. These are green plants, cyanobacteria, as well as many painted bacteria having chlorophyll (and other pigments) and absorbing sunny energy. The process at which its absorption occurs is called photosynthesis.

Hemoautotrofy.use the chemical energy of oxidation of inorganic substances (sulfur, hydrogen sulfide, ammonia, iron, etc.). These are serobacteria, hydrogen breaccteries, ferrucks, nitrifying bacteria, etc. Hemoautotrofa play a major role in groundwater ecosystems, as well as in the special ecosystems of rift zones of the ocean bottom, where hydrogen sulfide sulfide from the slabs, which is oxidized by serobacteria. In terrestrial ecosystems, the role of nitrifying bacteria play a significant role.

Heterotrophs.These organisms feed on ready organic substanceswhich are synthesized by producers, and together with these substances receive energy. Heterotrophs in the ecosystem are consultations (from the Latin word Consume - I consume) consuming organic matter, and rinducents, decomposing it to simple compounds. There are several groups of consumes.

Phytofagi (roar). These include animals that feed on alive plants. Among phytophages there are small organisms, such as a wave or grasshopper, and giants, such as an elephant. Petophage are almost all agricultural animals: cow, horse, sheep, rabbit. The main phytophages in the aqueous ecosystems are microscopic organisms of herbivorous plankton that feed on algae. There are large phytophages in these ecosystems, for example, a white Cupid fish, eating plants that irrigation canals overgrow. Important phytofag - beaver. It is powered by branches of trees, and from trunks builds dams regulating the water regime.

Zoofagi (Predators, carnivorous). Zoofagi is very diverse. These are small animals that feed on amoebas, worms or races. And large, such as wolf. Predators that feed on smaller predators are called second-order predators. Water ecosystems are widespread zoofagi filtrates, as part of this group - and microscopic crustaceans and whale. Filtrates play a huge role In self-purification of polluted water (Fig. 30). Only plankton marine grinding crayfish from the kind of Kalanus for several years can help the waters of the world's ocean!

There are predator plants (Rosyanka, bubble), which are used in the eating insects. True, their way of nutrition is different from animal predators. They "catch" small insects, but do not swallow them, but "digest", highlighting the enzymes on their surface. There are predators and among soil fungi, which "catch" microscopic round worms-nematodes.

Symbiotrofa. These are bacteria and mushrooms that feed on root plants. Symbiotrofses are very important for the life of the ecosystem. Nights of mushrooms, entangling roots of plants, help the absorption of water and minerals. Bacteria-symbiotrofses absorb gas nitrogen gas from the atmosphere and bind it to the compounds available to plants (ammonia, nitrates). This nitrogen is called biological (as opposed to nitrogen of mineral fertilizers).

Symbiotrofam includes microorganisms (bacteria, single-celled animals), which live in the digestive path of animal phytophages and help them to digest food. Such animals like a cow, without the help of symbiotrofs are not able to digest eaten grass.

Detritophagi - Organisms feed on dead organic matter. These are multi-ninexes, rainworms, beetles-insuries, crayfish, crabs, sacking and many others. A significant variety of dotritophage species is associated with soil. Numerous detrotophages that destroy the wood (Fig. 31).

Organisms that feed on excrement are called coprophagami. Some organisms are used in food both plants and animals and even child and belong to euryfagam (omnivorous) - Bear, Fox, Pig, Rat, Chicken, Crow, Cockroaches. Euryfag is both a person.

Roducenie - Organisms that are close to childhood in their position in the ecosystem, as they also feed on a dead organic matter. However, the relegates are bacteria and mushrooms - destroy organic substances to mineral compounds that are returned to the soil solution and are again used by plants.

For the processing of a dead organic matter, the Rindunts need time. Therefore, in the ecosystem there is always a stock of this substance - deriters. Detriton is the opead of the leaves on the surface of the forest soil (last 2-3 years), the barrel of the fallen tree (persists 5-10 years), the humus of the soil (hundreds of years), the deposition of the organic matter at the bottom of the lake - sapropel and peat on the lake (saved thousands years). The most long-lasting detritus are stone coal and oil.

Products, phytophages, predators are associated in the process of "work" of the ecosystem, that is, the assimilation and spending of energy in the production of organic matter and, as it were, participate in the "relay" of energy transmission. The number of the participant "Restament" is his trophic level. The first trophic level is produced, the second - phytophages, the third - first-order predators, the fourth - the predators of the second order. In some ecosystems, for example in the lake, the number of trophic levels can reach 5-6.

In fig. 32 shows the structure of the ecosystem, the base of which is plants - photoautotrophs, and in Table. 1 shows examples of representatives of different trophic groups for some ecosystems.

Table 1

Representatives of different trophic groups in some ecosystems

Consider what role representatives of different groups of living organisms like plants, animals, mushrooms play in the ecosystem.

Environmental system

Such a biological system includes a combination of living organisms and their habitats, as well as, the systems of links between them, thanks to which the mutual exchange of energy and substances occurs.

An example of an ecosystem for our task can serve as a forest. The ecosystem of which includes:

• plants - trees and herbs growing in it;
• animals - dwelling in a given area;
• mushrooms - growing in the forest.
• birds - trees living on branches

Depending on the territorial features of the range, other species may be located in certain places. For example, if there is a pond or river in the forest, then you can add fish to this system.

In general, the ecosystem implies the totality of all the inhabitants of this system, which are located and live in some conditions. In this case, all elements of the system are interconnected by the food chain. The relationship lies in the adaptation and role of each element of the system for other types of organisms of this system.

The role of plants, animals and mushrooms

A variety of types of living organisms in the ecosystem are closely related to each other and can not exist separately. Plants, animals and mushrooms use the results of each other's vital activity. They serve as food for each other, and create certain behavioral features.

For example, plants feed on moisture from the ground and minerals. As a result of photosynthesis, nutrients are formed. Plants themselves grow and multiply due to this and create a food environment for animals.

Animals feed on plants and on one side are obtained nutrients for themselves, and on the other hand, limit the number of plants. Also animals can use plants for disguise, for their livelihoods.

Mushrooms process the dead organisms in the Pump, which gives the mineral substances the land from which plants feed on. Also mushrooms are food for animals, and the dead animals with organic substances for plants.