Ecological role of decomposers

Decomposers return mineral salts to the soil and water, making them available to autotrophic producers, and thus closing the biotic cycle. Therefore, ecosystems cannot survive without decomposers (unlike consumers, which were probably absent from ecosystems during the first 2 billion years of evolution, when ecosystems consisted of only prokaryotes).

Abiotic and biotic factors regulating ecosystems

Research by N.I. Bazilevich et al. (1993) established that in terrestrial ecosystems there are two groups of factors regulating destructive processes that play a very significant role in the biological cycle.

see also

Sources

1. Bigon M., Harper J., Townsend K. Ecology. Individuals, populations and communities: in 2 volumes. M.: Mir, 1989. - 667 pp., illus.
2. Vronsky A.V., Applied ecology: tutorial. Rostov n/d.: Publishing house "Phoenix", 1996, 512 p. ISBN 5-85880-099-8
3. Garin V. M., Klenova I. A., Kolesnikov V. I. Ecology for technical universities. Series " Higher education" Ed. prof. V. M. Garina. Rostov n/d.: Publishing house "Phoenix", 2003, 384 p. ISBN 5-222-03768-1

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2010.

See what “Reducers” are in other dictionaries: - [from lat. reducens (reducentis) returning, restoring], destructors, bioreducers, organisms that decompose dead organic matter and turn it into non organic matter , assimilated by other organisms. Decomposers include...

Heterotrophic organisms that convert organic residues into inorganic substances during their life. Typical decomposers are bacteria and fungi. Reducers are the final link in the food chain in the ecological pyramid. lat.Reducere… … Dictionary of business terms

- (from the Latin reducens genus reducentis returning, restoring), organisms (saprotrophs) that decompose dead organic matter (corpses, waste) and transform it into inorganic substances that are able to assimilate other organisms... Big encyclopedic Dictionary

- (from Latin reducens, genus reducentis returning, restoring), destructors, organisms that feed on dead organic matter. substance and subjecting it to mineralization (destruction), i.e. destruction to b. or m. simple inorganic. connections to... Biological encyclopedic dictionary

Organisms that feed on dead organic matter and subject it to mineralization, i.e., destruction into more or less simple inorganic compounds, which are then used by producers. R. include mainly bacteria and fungi.... ... Dictionary of microbiology

decomposers- Organisms such as bacteria and fungi that feed on nonliving protoplasm, causing it to decompose and eventually dissolve in a liquid medium. Topics oceanology EN… …

Technical Translator's Guide Ov; pl. (unit decomposer, a; m.). [lat. reducens (reducentis) returning, restoring] Biol. Organisms that break down dead organic matter and convert it into inorganic matter that serves as food for other organisms. * * * decomposers (from Lat...

decomposers encyclopedic Dictionary - skaidytojai statusas T sritis ekologija ir aplinkotyra apibrėžtis Organizmai (pvz., bakterijos, kai kurie grybai), skaidantys organines medžiagas į paprastesnius neorganinius junginius, kuriuos augalai panaudoja savo mitybai. atitikmenys: engl.… …

Ekologijos terminų aiškinamasis žodynas - (lat. reduco to take back, return, restore; from re + duco to lead) organisms that mineralize organic substances, including products of dissimilation of other organisms; R. includes bacteria and fungi...

Large medical dictionary - (from lat. reducens, Genitive reducentis returning, restoring) organisms (saprophytes) that mineralize dead organic matter, i.e., decompose it into more or less simple inorganic compounds; overwhelming... ...

Great Soviet Encyclopedia Concept of community and ecosystem. Population group different types certain territory, forms a community. The idea of ​​any landscape is primarily associated with its vegetation. Tundra, taiga, deciduous forests, meadows, steppes, and deserts consist of a variety of plant communities. Birch forests differ from oak forests not only in tree composition, but also in undergrowth and grass cover. Each plant community inhabited by its characteristic communities of animals, fungi and microorganisms.

All communities of plants, animals, microorganisms, and fungi are in close connection with each other, creating an inextricable system of interacting organisms and their populations - a biocenosis, which is also called a community. Communities of any size and level can be identified. For example, in a steppe community there is a community of meadow steppes, and in it there are communities of plants, vertebrate and invertebrate animals, and microorganisms.

The environment and the community, as well as members of the community, exchange substances and energy with each other: living organisms receive substances and energy from the environment or from each other and return them back to the environment. Thanks to these exchange processes, organized in the form of energy flow and circulation of substances, the community (biocenosis) and its environment represent an inextricable unity, one complex system. Such a system is called an ecosystem or biogeocenosis (Fig. 102). IN Lately the term "ecosystem" is used more often.

Rice. 102. Ecosystem of coniferous (top) and mixed forests

Functional groups of organisms in a community. Any community consists of a collection of organisms that, based on the type of nutrition, can be divided into three functional groups. Green plants are autotrophs. They are able to accumulate solar energy during photosynthesis and synthesize organic substances. Autotrophs are producers, i.e. producers of organic matter, the first functional group of organisms in the biocenosis.

Any community also includes heterotrophic organisms that require ready-made organic substances for nutrition. There are two groups of heterotrophs: consumers, or consumers, and decomposers, i.e., destroyers. Animals are considered consumers. Herbivores eat plant foods, while carnivores eat animal foods. Decomposers include microorganisms - bacteria and microscopic fungi. Reducers decompose animal excretions, residues dead plants, animals and microorganisms and other organic substances. Destroyers feed organic compounds, formed during decomposition. During the feeding process, decomposers mineralize organic matter into water, carbon dioxide and mineral elements. Mineralization products are again used by producers.

Consequently, in the ecosystem food and energy connections go in the directions

All three listed groups of organisms exist in any community. Each group includes many populations inhabiting the ecosystem. Only collaboration all three groups ensure the functioning of the ecosystem.

Examples of ecosystems. Different ecosystems differ from each other both in the species composition of organisms and in the properties of their habitat. Consider a deciduous forest and a pond as examples.

Deciduous forests include beech, oak, hornbeam, linden, maple, birch, aspen, rowan and other trees whose foliage falls in the fall. There are several tiers of plants in the forest: high and low woody, shrubs, grasses and moss ground cover. Plants in the upper tiers are more light-loving and better adapted to fluctuations in temperature and humidity than plants in the lower tiers. Shrubs, grasses and mosses in the forest are shade-tolerant; in summer they exist in twilight, which forms after the leaves of the trees have fully expanded. On the surface of the soil lies a litter consisting of semi-decomposed remains of fallen leaves, twigs of trees and shrubs, and dead grass (Fig. 103).

Rice. 103. Deciduous forest ecosystem

The fauna of deciduous forests is rich. There are many burrowing rodents (mice, voles), burrowing insectivores (shrews), and predators (fox, badger, bear). There are mammals that live in trees (lynx, squirrel, chipmunk). The group of large herbivores includes deer, elk, and roe deer. Wild boars are widespread.

Birds nest in different layers of the forest: on the ground, in bushes, on trunks or in hollows and on the tops of trees. There are many insects that feed on leaves (for example, caterpillars) and wood (bark beetles). In addition to insects, the litter and upper soil horizons are home to a huge number of other invertebrate animals ( earthworms, mites, insect larvae), a mass of fungi and bacteria.

An example of an ecosystem where water serves as the living environment for organisms is the well-known ponds. Rooting or large floating plants (reeds, cattails, water lilies) settle in the shallow waters of ponds. Throughout the entire water column to the depth of light penetration there are small floating plants, mostly algae, called phytoplankton. When there is a lot of algae, the water turns green, as they say, “blooms.” Phytoplankton contains many diatoms and green algae, as well as cyanobacteria.

Insect larvae, tadpoles, crustaceans, herbivorous fish and mollusks feed on living plants or plant debris, predatory insects and fish eat a variety of small animals, and large ones predatory fish They hunt both herbivores and predatory, but smaller fish.

Organisms that decompose organic matter (bacteria, flagellates, fungi) are distributed throughout the pond, but there are especially many of them at the bottom, where the remains of dead plants and animals accumulate.

We see how different we are appearance, and by the species composition of forest and pond ecosystem populations. The habitat of species is different: in the forest - air and soil; in the pond there is air and water. However, the functional groups of living organisms are of the same type. Producers in the forest are trees, shrubs, grasses, mosses; in the pond there are floating plants, algae and blue-greens. Consumers in the forest include animals, birds, insects and other invertebrate animals (the latter inhabit the soil and litter). In a pond, consumers include insects, various amphibians, crustaceans, herbivores and predatory fish. Decomposers (fungi and bacteria) are represented in the forest by terrestrial forms, and in the pond by aquatic forms.

These same functional groups of organisms exist in all terrestrial (tundra, coniferous and deciduous forests, steppes, meadows, deserts) and aquatic (oceans, seas, lakes, rivers, ponds) ecosystems.

1. Define community, biogeocenosis, producers, decomposers, consumers. Give examples of biogeocenoses (ecosystems) in your area.
2. List the most important components of the ecosystem and reveal the role of each of them.
3. How and why the life of an oak grove will change in cases where: a) all the bushes are cut down; b) chemically destroyed herbivorous insects?

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

Producers constitute a group of autotrophic organisms that, by consuming minerals from the biotope and the energy of sunlight, create primary organic substances. This group includes plants and some bacteria.

Producers are autotrophic organisms capable of building their bodies using inorganic compounds (Fig. 5).

Rice. 5.

Decomposers are organisms that decompose the remains of dying organisms, break down organic substances into inorganic ones, and thereby return mineral substances to the biotope that were “removed” by producers. For example, these are some types of bacteria and single-celled fungi.

Biogeocenosis and ecosystem and their structure

An ecosystem is a functional unity of living organisms and their habitat. Basic characteristics ecosystems - its dimensionlessness and lack of rank. The replacement of some biocenoses by others over a long period of time is called succession. Succession occurring on a newly formed substrate is called primary. Succession in an area already occupied by vegetation is called secondary succession.

The unit of ecosystem classification is the biome -- natural area or an area with certain climatic conditions and a corresponding set of dominant plant and animal species.

A special ecosystem - biogeocenosis - area earth's surface with homogeneous natural phenomena. Components biogeocenoses are climatope, edaphotope, hydrotope (biotope), as well as phytocenosis, zoocenosis and microbiocenosis (biocenosis).

In order to obtain food, people artificially create agroecosystems. They differ from natural ones in their low resistance and stability, but in higher productivity.

An ecological system, or ecosystem, is the basic functional unit in ecology, since it includes organisms and the inanimate environment - components that mutually influence each other’s properties, and the necessary conditions to support life in the form that exists on Earth. The term ecosystem was first proposed in 1935 by the English ecologist A. Tansley. Thus, an ecosystem is understood as a set of living organisms (communities) and their habitats, which, thanks to the cycle of substances, form a stable system of life.

Rice. 6.

In Russian literature, the term “biogeocenosis”, proposed in 1940 by V. N Sukachev, is widely used. According to his definition, biogeocenosis is “a collection of homogeneous natural phenomena(atmosphere, rock, soil and hydrological conditions), which has a special specificity of the interactions of these components that make it up and certain type exchange of matter and their energy between themselves and other natural phenomena and representing an internally contradictory dialectical unity located in constant movement, development".

In the biogeocenosis V.N. Sukachev distinguished two blocks: ecotope - the set of conditions of the abiotic environment and biocenosis - the set of all living organisms. An ecotope is often considered as an abiotic environment not transformed by plants (the primary complex of factors of the physical-geographical environment), and a biotope as a set of elements of the abiotic environment modified by the environment-forming activities of living organisms.

There is an opinion that the term “biogeocenosis” is significantly to a greater extent reflects the structural characteristics of the macrosystem under study, while the concept of “ecosystem” includes, first of all, its functional essence. In fact, there is no difference between these terms.

Ecology. Part A

1. The limiting factor for plant life at great depths is the lack of

1) food 2) heat 3) light 4) oxygen

2. Factors are called anthropogenic

related to human activities

abiotic nature

caused by historical changes in the earth's crust

determining the functioning of biogeocenoses

3. Abiotic environmental factors include

root digging by wild boars

locust invasion

accumulation of droppings in bird colonies

heavy snowfall

4. A factor limiting the growth of herbaceous plants in a spruce forest is a disadvantage,

light 3) water

heat 4) minerals

5. The effect of the anthropogenic factor on living nature is not natural

character, therefore in organisms

mutations occur constantly

adaptations to it have not been formed

developed defensive reactions towards him

most mutations are preserved by natural selection

6. Type of relationship between nodule bacteria and leguminous plants -

predator - prey 4) symbiotic

7. Competitive relations in the biocenosis arise between

predators and prey

producers and consumers

species with similar needs

8. The signal that causes the onset of leaf fall in plants in temperate climates is

decrease in air temperature

reduction in daylight hours

decrease nutrients in the soil

formation of a cork layer in the petiole

9. Competition in the ecosystem exists between

oak and birch 3) spruce and lily of the valley

spruce and blueberry 4) oak and porcini mushroom

10. Biotic components of an ecosystem include

gas composition of the atmosphere

soil composition and structure

climate and weather features

links in food chains

11. In the lake ecosystem, consumers include

fish and amphibians

saprotrophic bacteria

algae and flowering plants

microscopic fungi

12. Consumers in the process of circulation of substances in the biosphere

create organic substances from minerals

finally decompose organic matter into minerals

decompose minerals

consume ready-made organic substances

13. A body of water inhabited by various species of plants and animals is

biogeocenosis 3) biosphere

noosphere 4) agroecosystem

14. Identify a properly constructed food chain.

spruce seeds → hedgehog → fox

fox →hedgehog →spruce seeds

spruce seeds→mouse→fox

mouse → spruce seeds → hedgehog

15. Organisms that decompose organic substances into mineral ones -

producers

consumers of the first order

consumers of the second order

decomposers

16. The age structure of the population is characterized by

ratio of females to males

number of individuals

ratio of young and mature individuals

its density

17. The species structure of the biogeocenosis of a deciduous forest, in contrast to a coniferous forest, is characterized

tiered placement of organisms

presence of producing organisms

predominance of consumer biomass

the diversity of species living in it

18. The increase in the population of victims contributes to

reduction in predator numbers

increase in the number of competitors

reduction in the number of symbionts

19. In the ecosystem coniferous forest Second-order consumers include

taiga ticks

forest mice

spruce

soil bacteria

20. Processes in an ecosystem that maintain a certain ratio of producers and consumers of organic matter are called

biological rhythms

fitness

self-regulation

change of ecosystems

21. In the process of the cycle of substances in the biosphere, decomposers, in contrast to producers,

participate in the formation of organic substances from inorganic

decompose organic residues and use the energy contained in them

use sunlight for nutrient synthesis

absorb oxygen and use it to oxidize organic substances

22. The branching of a food web depends on

limited reproduction rate

amount of energy produced in organisms

diversity of organisms by feeding method

intensity of gas exchange in the biocenosis

23. Identify a correctly composed food chain.

hawk -> thrush -> caterpillar -> nettle

nettle -> thrush -> caterpillar -> hawk

caterpillar -> nettle -> thrush -> hawk

nettle -> caterpillar -> thrush -> hawk

24. Agroecosystems include

mixed forest

water meadow

overgrown lake

wheat field

25. The largest number of species is found in an ecosystem

birch grove

tropical forest

26. Anthropogenic change in the steppe ecosystem is considered

formation of chernozem soils

fluctuations in rodent numbers

alternating dry and wet periods

disturbance of vegetation cover due to plowing of the steppe

27. An example of a change in ecosystem is

death of above-ground parts of plants in a meadow in winter

reducing the number of predators in the forest

change appearance forest community in winter

overgrowing of a reservoir

28. Why is a corn field considered an artificial community?

it is dominated by producers of one species

it includes populations of plants and animals

it lacks saprotrophic organisms

its stability is supported by the diversity of consumers

29. Agrocenoses, in contrast to natural biocenoses,

do not participate in the cycle of substances

exist due to microorganisms

cannot exist without human participation

consist of large number species of plants and animals

30. The reasons for the change from one biogeocenosis to another are

seasonal changes in nature

changes in weather conditions

fluctuations in the population size of one species

changes in the environment as a result of the vital activity of organisms

31.The repeated use of chemicals in the ecosystem by living organisms is facilitated by

self-regulation

cycle of substances

population fluctuations

metabolism and energy conversion

32. The agroecosystem of an orchard differs from the ecosystem of an oak forest

longer power chains

less stability

closed cycle of substances

33. Agroecosystems are less stable than ecosystems, since they

there are no producers and decomposers

limited species composition plants

animals occupy the first trophic level

closed circulation of substances and energy conversion

34. Mixed forest is a more stable ecosystem than spruce forest, since in it

large number of species and varied food relationships

tiering is expressed

there are producers, consumers and decomposers

reduced exposure to solar radiation

35. The circulation of nitrogen between non-living bodies and living organisms in the community

called

rule of the ecological pyramid

circulation of substances

self-regulation

metabolism and energy

36. Mineralization of soil organic compounds is carried out thanks to

activities

plant roots 3) microorganisms

cap mushrooms 4) terrestrial animals

37. The primary source of energy for the circulation of substances in most biogeocenoses

sunlight

activity of producers in the ecosystem

microbial activity

dead organic matter

38. A large number of species in the ecosystem, the presence of branched food networks, tiers are signs

sustainable development of the ecosystem

transition of a stable ecosystem to an unstable one

unstable state of the ecosystem

change from one ecosystem to another

39. The energy necessary for the circulation of substances is drawn from space

heterotrophic organisms

putrefactive bacteria

nodule bacteria

plants during photosynthesis

40. Bacteria, being included in the cycle of substances in the biosphere,

participate in the formation of the ozone shield

decompose organic matter to inorganic

promote the formation of limestones

neutralize radioactive substances in the soil

41. Why has the number of rabbits brought to Australia increased many times over?

they had no enemies in the new territory

The continent has a dry climate

the continent is dominated by herbaceous plants

they gained an advantage over marsupials

42. The cosmic role of plants on Earth is that they

accumulate solar energy

absorb from environment minerals

absorb carbon dioxide from the environment

release oxygen

43. Organisms in the process of life constantly change their habitat, which contributes to

cycle of substances

self-development of ecosystems

reproduction of organisms

growth and development of organisms

44. During the cycle of substances, the energy contained in organic substances is released as a result

1) decay 3) chemosynthesis 2) photosynthesis 4) photolysis

45. The main reason for the instability of ecosystems is

fluctuation in ambient temperature

lack of food resources

imbalance in the circulation of substances

increased abundance of some species

46. ​​Mushrooms, being included in the cycle of substances in the biosphere,

decompose dead organic matter

reduce inorganic carbon reserves

participate in the primary synthesis of organic substances

participate in the accumulation of oxygen in the atmosphere

47. Self-regulation in biogeocenosis is manifested in the fact that

species are rapidly reproducing

the number of individuals changes

some species are not completely destroyed by others

the population size of certain species is increasing

48. The process that ensures the preservation of balance in an ecosystem is called

metabolism 3) energy conversion

self-regulation 4) biogenic migration of atoms

Answers