- Habitat (ecological niche) is a set of specific abiotic and biotic conditions in which a given individual, population or species lives, a part of nature that surrounds living organisms and has a direct or indirect impact on them. Habitat (ecological niche), often overlaps with the term "area" - the geographical distribution of a biological species. For example, a brown bear. Habitat (ecological niche) - forests. The habitat is wherever there are such forests (Europe, Asia, North America). From the environment, organisms receive everything they need for life and secrete metabolic products into it. The term is often considered synonymous with environment. The environment of each organism is composed of many elements of inorganic and organic nature and elements introduced by man and his production activities. Moreover, some elements may be partially or completely indifferent to the body, others are necessary, and others have a negative effect.
There are natural and artificial (man-made) habitats. Natural habitats are mainly divided into ground-air, soil, water and intraorganismal. Individual properties and elements of the environment that affect organisms are called environmental factors. All environmental factors can be divided into three large groups:
The abiotic environment (environmental factors) is a set of conditions in the inorganic environment that affect the organism. (Light, temperature, wind, air, pressure, humidity, etc.) For example: accumulation of toxic and chemical elements in the soil, drying out of water bodies during drought, increasing daylight hours, intense ultraviolet radiation.
The biotic environment (environmental factors) is a set of influences of the life activity of some organisms on others. (The influence of plants and animals on other members of the biogeocenosis) For example: soil destruction by wild boars and moles, a decrease in the number of squirrels in lean years.
Anthropogenic (anthropogenic) factors are all forms of activity of human society that change nature as the habitat of living organisms or directly affect their lives. The separation of anthropogenic factors into a separate group is due to the fact that currently the fate of the Earth's vegetation and all currently existing species of organisms is practically in the hands of human society.
It is also possible to distinguish the following components of the habitat: natural bodies of the habitat, hydroenvironment, air space of the environment, anthropogenic bodies, radiation and gravitational fields of the environment.
From our article you will learn what the environment is. This concept is widely used both in ecology and in everyday life. Each environment has its own conditions and types of organisms. How are they interconnected? Let's figure it out together.
What is an environment: definition of the concept
This word has many meanings. It can mean a day of the week, a piece of land, a social setting, or a solution with uniform conditions. The word environment appears in different languages, but is literally translated as “middle.” What is the environment from an ecological point of view? This is a set of conditions in which living organisms and their communities live.
Classification
The habitat is also called the ecological niche of organisms. For each of them, this is the basis for obtaining various substances, which is made up of many components.
In relation to the species itself, it can be external and internal. What is their difference? Internal is the totality of all body fluids, which are contained in special reservoirs. The term “internal environment” was first introduced into science by a French physician and physiologist. It never comes into contact with the external environment. Thanks to this feature, homeostasis, or constancy of conditions, is continuously maintained.
And what is external – all the conditions in which this or that species lives. According to the conditions of existence, four types of environment are distinguished. The most diverse in terms of conditions and densely populated is the ground-air one. The water and soil environments differ significantly from it. Another environment in which life is possible is organisms of other species.
Environmental factors
Each environment is unique in its own way. This feature is determined by unique conditions, or environmental factors. They directly or indirectly have a continuous influence on all living things in every habitat. What is temperature, humidity, light, pressure? These are components of inanimate nature. They belong to the group of abiotic factors.
Ground-air environment
The leading factors here are the amount of solar energy, air temperature, humidity and gas composition of the air. The ground-air environment has rightfully earned the title of the most diverse in terms of conditions.
What is a habitat for representatives of the plant world? This is a place that will provide conditions for photosynthesis to occur. Therefore, the limiting factor for plants is the availability of light. In its spectrum there are areas that have different effects on organisms. Ultraviolet radiation is destructive to living things, so it is almost completely absorbed by the Earth's ozone layer. Half of the spectrum is visible rays. They are used by plants for the synthesis of organic matter, and animals - for visual perception. Infrared rays are a source of thermal energy and are therefore used by many species to increase body temperature.
Temperature significantly affects the rate of metabolic reactions. Its optimal indicator ranges from 10 to 30 degrees with a + sign. Living organisms have a number of adaptations to endure unfavorable conditions. They can fall into a state of cyst or suspended animation and are capable of thermoregulation.
Properties of water
What is the environment for fish and crustaceans? These are fresh and salt water bodies. The inhabitants of the water column represent the ecological groups of plankton and nekton. The former include bacteria, blue-green algae, jellyfish, and radiolaria. Some of them actively swim on their own, but even they are not able to resist currents. Therefore, planktonic organisms have a number of adaptations for movement in the water column. These include small sizes and low specific gravity.
Those animals that move independently in the water column are called nekton. What is their habitat? These are also diverse bodies of water. This ecological group includes cetacean mammals, cephalopods, and fish. All of them have a streamlined body shape and well-developed organs of movement.
The aquatic environment is temperature, light level, salinity and bottom conditions.
Life in the soil
What is a habitat in which there is virtually no light and movement is hampered by a high density of particulate matter? This is the soil. For a huge number of organisms, such conditions are quite favorable. These are protozoa, worms, insects, gastropods, and some vertebrates. The main adaptations to living conditions in the soil include the absorption of oxygen through the integument, the presence of burrowing limbs, and a worm-like body shape.
Other organisms
So what is habitat? This is the totality of all the conditions in which organisms live. Each of them is distinguished by the predominant effect of its environmental factors.
Habitat refers to the space used by living organisms to exist. Thus, the topic is directly related to the question of the life activity of any creature. There are four types of habitats, in addition, there are various factors that transform external influences, so they also need to be considered.
Definition
So what is an animal habitat? The definition appeared back in the nineteenth century - in the works of the Russian physiologist Sechenov. Every living organism constantly interacts with surrounding phenomena, which it was decided to call the environment. Her role is of a dual nature. On the one hand, all life processes of organisms are directly related to it - this is how animals get food, they are influenced by climate. On the other hand, their existence has no less influence on the environment, largely determining it. Plants maintain oxygen balance and shade the soil, animals make it looser. Almost any change is caused by living organisms. The habitat needs a comprehensive study by anyone who wants to have an understanding of biology. It is also important to know that some creatures can live in different conditions. Amphibians are born in an aquatic environment, and often winter and feed on land. Airborne beetles often require soil or water to reproduce.
Water
The aquatic environment is the totality of all the oceans, seas, glaciers and continental waters of our planet, the so-called hydrosphere, in addition, sometimes it also includes the snow of the Antarctic, atmospheric fluids and those contained in organisms. It occupies more than seventy percent of the surface with the bulk in the oceans and seas. Water is an integral part of the biosphere, not only of reservoirs, but also of air and soil. Every organism needs it to survive. Moreover, it is water that distinguishes the Earth from neighboring planets. In addition, it played a key role in the development of life. It accumulates organic and inorganic substances, transfers heat, shapes the climate and is found in both animal and plant cells. That is why the aquatic environment is one of the most important.
Air
The mixture of gases that forms the Earth's atmosphere plays a vital role for all living organisms. The air habitat guided evolution, since oxygen forms a high metabolism, which determines the structure of the respiratory organs and the water-salt metabolism system. Density, composition, humidity - all this has serious implications for the planet. Oxygen was formed two billion years ago during volcanic activity, after which its share in the air has steadily increased. The modern human environment is characterized by a 21% content of this element. An important part of it is also the ozone layer, which prevents ultraviolet radiation from reaching the Earth's surface. Without it, life on the planet could be destroyed. Now the safe human habitat is under threat - the ozone layer is being destroyed due to negative environmental processes. This leads to the need for conscious behavior and constant choice of the best solutions not only for people, but also for the Earth.
Soil
Many living organisms live in the earth. The habitat is also used by plants, which provide food for most of the planet's living things. It is impossible to unambiguously determine whether soil is a nonliving formation, which is why it is called a bioinert body. According to the definition, this is a substance that is processed during the life of organisms. Soil habitat consists of solid matter including sand, clay, and silt particles; liquid component; gaseous - this is air; living - these are the creatures that inhabit it, all kinds of microorganisms, invertebrates, bacteria, fungi, insects. Each hectare of land is home to five tons of such forms. The soil habitat is intermediate between aquatic and ground-air, therefore the organisms living in it often have a combined type of respiration. You can meet such creatures even at impressive depths.
Interaction of organisms and environment
Each creature differs in the presence of metabolism and cellular organization. Interaction with the environment occurs constantly and must be studied comprehensively due to the complexity of the processes. Each organism directly depends on what is happening around it. The land-air environment of a person is influenced by precipitation, soil conditions and temperature range. Some of the processes are beneficial to the body, some are indifferent, and others are harmful. Each has a separate definition. For example, homeostasis is the constancy of the internal system that distinguishes living organisms. The habitat can change, which requires adaptation - movements, growth, development. Metabolism is the exchange of substances accompanied by chemical reactions, such as respiration. Chemosynthesis is the process of creating organic matter from sulfur or nitrogen compounds. Finally, it is worth remembering the definition of ontogeny. This is a set of transformations of the body that are influenced by all environmental factors over the entire period of its existence.
Environmental factors
To better understand biological processes, it is also necessary to study this definition. are a complex of environmental conditions that affect a living organism. They are divided according to a complex classification into several types. The adaptation of an organism to them is called adaptation, and its external appearance, reflecting environmental factors, is called a life form.
Nutrients
This is one of the types of environmental factors that affect living organisms. The habitat contains salts and elements supplied with water and food. Biogenic ones are those that are needed in large quantities for the body. For example, this is phosphorus, important for the formation of protoplasm, and nitrogen, the basis for protein molecules. The source of the first is dead organisms and rocks, and the second is atmospheric air. Lack of phosphorus affects existence almost as acutely as lack of water. Elements such as calcium, potassium, magnesium and sulfur are slightly inferior in importance. The first is necessary for shells and bones. Potassium ensures the functioning of the nervous system and plant growth. Magnesium is part of the molecules of chlorophyll and ribosomes, and sulfur is part of amino acids and vitamins.
Abiotic environmental factors
There are other processes that affect living organisms. Habitat includes factors such as light, climate and the like, which are by definition abiotic. Without them, the processes of respiration and photosynthesis, metabolism, seasonal flights, and the reproduction of many animals are impossible. First of all, light is important. Its length, intensity and duration of exposure are taken into account. In relation to it, a whole classification is distinguished, which is studied by biology. A habitat filled with light is needed by heliophytes - meadow and steppe grasses, weeds, and tundra plants. Sciophytes need shade; they prefer to live under the forest canopy - these are forest herbs. Facultative heliophytes can adapt to any conditions: trees, strawberries, and geraniums belong to this class. An equally important factor is temperature. Each organism has a certain range that is comfortable for life. Water, the presence of chemicals in the soil and even fires - all this also concerns the abiotic sphere.
Biotic factors
Anthropogenic factor
Aquatic, air or terrestrial habitats are always associated with human activity. People intensively change the world around them, greatly influencing its processes. Anthropogenic factors include any impact on organisms, the landscape or the biosphere. It can be direct if it is directed at living beings: for example, improper hunting and fishing undermine the numbers of some species. Another option is indirect impact, when a person changes the landscape, climate, air and water conditions, and soil structure. Consciously or unconsciously, man destroys many species of animals or plants, while cultivating others. This is how a new environment appears. There are also accidental impacts, such as the sudden introduction of alien organisms in cargo, improper drainage of swamps, the creation of dams, and the spread of pests. However, some creatures become extinct without any human intervention, so blaming people for all environmental problems is simply unfair.
Limiting factors
All kinds of influences exerted on organisms from all sides manifest themselves to varying degrees. Sometimes the key substances are those that are required in minimal quantities. Accordingly, it was developed. It assumes that the weakest link in the chain of needs of the body is its endurance as a whole. Thus, if the soil contains all the elements except one necessary for growth, the harvest will be poor. If you add only the missing one, leaving all the others in the same quantity, it will become better. If you add everything else without correcting the deficiency, no changes will occur. The missing element in such a situation will be the limiting factor. However, it is worth considering the maximum impact. It is described by Shelford's law of tolerance, which suggests that there is only a certain range in which a factor can remain beneficial to the body, but in excess it becomes harmful. Ideal conditions are called the optimum zone, and deviations from the norm are called oppression. The maximums and minimums of influences are called critical points, beyond which the existence of an organism is simply impossible. The degrees of tolerance to certain conditions are different for each living creature and allow them to be classified as more or less hardy varieties.
Habitat is the space in which the vital activity of living organisms takes place. If the origin of the habitat is not related to the life activity of organisms, we are dealing with a nonliving, or abiotic, environment. Otherwise, the habitat is called living, or biotic. There are four types of habitats on the planet: aquatic, ground-air, soil and living organisms themselves.
The concept of habitat
Living organisms are always in interaction with the natural formations and phenomena that surround them. About the historical unity of living organisms and their environment back in the 19th century. wrote the outstanding Russian physiologist I.M. Sechenov: “An organism without an external environment that supports its existence is impossible; therefore, the scientific definition of an organism must also include the environment that influences it.”
The set of natural conditions and phenomena surrounding living organisms, with which these organisms are in constant interaction, is called habitat.
The role of the environment is twofold. First of all, living organisms obtain food from the environment in which they live. In addition, different environments limit the spread of organisms around the globe. The hot and dry climate of the desert prevents most organisms from living there, just as the extreme cold in the polar regions means that only the hardiest species can live there. It is the environment that changes organisms by facilitating their improvement through natural selection. Organisms not only adapt to their environment, but evolve.
In turn, the vital activity of organisms affects the environment. The environment-forming role of living organisms is great. Plants release oxygen and thereby maintain its balance in the planet’s atmosphere. Tall plants (trees and shrubs) shade the soil, promote the redistribution of moisture, and together with herbs create a special microclimate. Plants and animals influence the structure and properties of the soil.
If the origin of natural phenomena is not connected with the life activity of living organisms, then we are dealing with an abiotic, or nonliving, habitat: these are various physical characteristics of the climate, chemical characteristics of water, soil, the nature of the substrate, background radiation, etc.
In the case when the forces and phenomena of nature owe their origin to the vital activity of organisms, the habitat is called biotic, or living. This is a collection of living organisms that influence other organisms through their vital activity.
The first three types of habitat constitute the abiotic environment, the fourth - the biotic environment.
Organisms can exist in one or more living environments. For example, fish live only in water. Humans, most species of birds, mammals, gymnosperms and angiosperms live in the ground-air environment. Many insects and amphibians begin their life path in one environment and continue in another (mosquito larvae develop in the wild, adult insects live in a ground-air environment; newts, predominantly aquatic animals, winter on land). Some insects require soil and ground-air environments to procreate (chafer beetle, bronze beetle).
This is that part of nature (a set of specific abiotic and biotic conditions) that surrounds living organisms and has a direct or indirect influence on them. On our planet, organisms have mastered four main habitats: 1) aquatic, 2) terrestrial (air), 3) soil, 4) the body of another organism, used by parasites and semi-parasites.
The concept of “living environment” should be distinguished from the concept of “habitat” - a set of vital environmental factors without which living organisms cannot exist (light, water, heat, air, soil). In contrast, other environmental factors, although they have a significant impact, are not vital for living organisms (for example, wind, flue gases, natural and artificial ionizing radiation, atmospheric electricity, etc.).
Elements of the environment that cause adaptive reactions - adaptations - in specific species and in their communities are called environmental factors.
Based on their origin and nature of action, all environmental factors are divided into abiotic(factors of the inorganic, or nonliving, environment), biotic(forms of influence of living beings on each other) and anthropogenic(all forms of human activity that affect living nature).
Abiotic factors divided into climatic (light, air and water temperature, air and soil humidity, wind), edaphic or soil-ground (mechanical and chemical composition of soils, their physical properties, etc.), topographic or orographic (terrain conditions), and other physical factors, including the effects of sea currents, waves and fire.
The above division is largely arbitrary: for example, the thermal and water regimes of the soil are not only edaphic, but also climatic factors, since these soil properties are largely determined by solar radiation and precipitation regimes.
Changes in environmental factors are observed throughout the year and day, and in the case of ebbs and flows in the ocean, during storms, showers, landslides, during cooling or warming of the climate, overgrowing of water bodies, constant grazing of livestock in the same area, etc.
The same environmental factor has different significance in the life of co-living organisms. For example, the salt composition of the soil is important for the mineral nutrition of plants, but is indifferent to most terrestrial animals. The intensity of illumination and the spectral composition of light are of paramount importance in the life of autotrophic organisms, but in the life of heterotrophs light does not have a noticeable effect, etc.
Environmental factors affect living organisms in different ways. They can act as stimuli causing adaptive changes in physiological functions; as limiters that make it impossible to exist in given conditions; as modifiers that cause morphological and anatomical changes in organisms.
