related to abiotic factors. Abiotic factors
ASTRAKHAN STATE TECHNICAL UNIVERSITY
ABSTRACT
Completed: st-ka gr. BS-12
Mandzhieva A.L.
Checked by: Associate Professor, Ph.D. Unrolled
Astrakhan 2009
Introduction
I. Abiotic factors
II. Biotic factors
Introduction
The environment is a set of elements that can have a direct or indirect effect on organisms. Elements of the environment that affect living organisms are called environmental factors. They are divided into abiotic, biotic and anthropogenic.
Abiotic factors include elements of inanimate nature: light, temperature, humidity, precipitation, wind, atmospheric pressure, background radiation, chemical composition of the atmosphere, water, soil, etc. Biotic factors are living organisms (bacteria, fungi, plants, animals ) interacting with the organism. Anthropogenic factors include features of the environment due to human labor activity. With the growth of the population and the technical equipment of mankind, the proportion of anthropogenic factors is constantly increasing.
It should be borne in mind that individual organisms and their populations are simultaneously affected by many factors that create a certain set of conditions in which certain organisms can live. Some factors can enhance or weaken the effect of other factors. For example, at an optimal temperature, the endurance of organisms to a lack of moisture and food increases; in turn, the abundance of food increases the resistance of organisms to adverse climatic conditions.
Rice. 1. Scheme of the action of the environmental factor
The degree of influence of environmental factors depends on the strength of their action (Fig. 1). With the optimal strength of the impact, this species lives normally, reproduces and develops (an ecological optimum that creates the best living conditions). With significant deviations from the optimum, both upward and downward, the vital activity of organisms is inhibited. The maximum and minimum values of the factor at which life activity is still possible are called endurance limits (tolerance limits).
The optimal value of the factor, as well as the limits of endurance, is not the same for different species and even for individual individuals of the same species. Some species can tolerate significant deviations from the optimal value of the factor, i.e. have a wide range of endurance, others have a narrow one. For example, a pine tree grows both on sands and in swamps where there is water, and a water lily immediately dies without water. Adaptive reactions of the organism to the influence of the environment are developed in the process of natural selection and ensure the survival of species.
The value of environmental factors is not equivalent. For example, green plants cannot exist without light, carbon dioxide and mineral salts. Animals cannot live without food and oxygen. Vital factors are called limiting (in their absence, life is impossible). The limiting effect of the limiting factor is also manifested at the optimum of other factors. Other factors may have a less pronounced effect on living things, such as the nitrogen content in the atmosphere for plant and animal organisms.
The combination of environmental conditions that provide enhanced growth, development and reproduction of each organism (population, species) is called the biological optimum. Creation of biological optimum conditions in the cultivation of crops and animals can significantly increase their productivity.
I. Abiotic factors
Abiotic factors include climatic conditions, which in various parts of the globe are closely related to the activity of the Sun.
Sunlight is the main source of energy that is used for all life processes on Earth. Thanks to the energy of sunlight, photosynthesis occurs in green plants, as a result of which all heterotrophic organisms are fed.
Solar radiation is heterogeneous in its composition. It distinguishes infrared (wavelength more than 0.75 microns), visible (0.40, - 0.75 microns) and ultraviolet (less than 0.40 microns) rays. Infrared rays make up about 45% of the radiant energy reaching the Earth and are the main source of heat that maintains the temperature of the environment. Visible rays make up about 50% of radiant energy, which is especially necessary for plants for the process of photosynthesis, as well as for ensuring visibility and spatial orientation of all living beings. Chlorophyll absorbs mainly orange-red (0.6-0.7 microns) and blue-violet (0.5 microns) rays. Plants use less than 1% of solar energy for photosynthesis; the rest of it is dissipated as heat or reflected.
Most of the ultraviolet radiation with a wavelength of less than 0.29 microns is retained by a kind of "screen" - the ozone layer of the atmosphere, which is formed under the influence of the same rays. This radiation is detrimental to living things. Ultraviolet rays with a longer wavelength (0.3-0.4 microns) reach the Earth's surface and in moderate doses have a beneficial effect on animals - they stimulate the synthesis of vitamin B, skin pigments (sunburn), etc.
Most animals are able to perceive light stimuli. Already in the protozoa, light-sensitive organelles ("eye" in green euglena) begin to appear, with the help of which they are able to respond to light exposure (phototaxis). Almost all multicellular organisms have a variety of photosensitive organs.
According to the requirements for the intensity of illumination, light-loving, shade-tolerant and shade-loving plants are distinguished.
Light-loving plants can develop normally only with intense lighting. They are widespread in dry steppes and semi-deserts, where the vegetation cover is sparse and the plants do not shade each other (tulip, goose onion). Light-loving plants also include cereals, plants of treeless slopes (thyme, sage), etc.
Shade-tolerant plants grow better in direct sunlight, but they can also tolerate shading. These are mainly forest-forming species (birch, aspen, pine, oak, spruce) and herbaceous plants (St. John's wort, strawberry), etc.
Shade-loving plants do not tolerate direct sunlight and develop normally in shading conditions. These plants include forest grasses - oxalis, mosses, etc. During deforestation, some of them may die.
Rhythmic changes in the activity of the light flux, associated with the rotation of the Earth around its axis and around the Sun, are noticeably reflected in wildlife. Daylight hours vary in different parts of the world. At the equator, it is constant throughout the year and is equal to 12 hours. As you move from the equator to the poles, the duration of daylight hours changes. At the beginning of summer, daylight reaches its maximum length, then gradually decreases, at the end of December it becomes the shortest and begins to increase again.
The reaction of organisms to the duration of daylight hours, expressed in a change in the intensity of physiological processes, is called photoperiodism. Photoperiodism is associated with the main adaptive reactions and seasonal changes in all living organisms. The coincidence of periods of the life cycle with the corresponding season (seasonal rhythm) is of great importance for the existence of species. The role of the trigger of seasonal changes (from spring awakening to winter dormancy) is played by the length of daylight hours, as the most constant change, foreshadowing a change in temperature and other environmental conditions. Thus, an increase in the length of daylight stimulates the activity of the gonads in many animals and determines the beginning of the mating season. The shortening of daylight hours leads to the attenuation of the function of the gonads, the accumulation of fat, the development of lush fur in animals, and the flight of birds. Similarly, in plants, the formation of hormones that affect flowering, fertilization, fruiting, tuber formation, etc. is associated with the lengthening of daylight hours. In autumn, these processes fade.
Depending on the reaction to the length of daylight hours, plants are divided into long-day plants, which bloom when the daylight period is 12 hours or more (rye, oats, barley, potatoes, etc.), short-day ones, in which flowering occurs when the day becomes short ( less than 12 hours) (these are plants of predominantly tropical origin - corn, soybeans, ifoso, dahlias, etc.) and neutral ones, the flowering of which does not depend on the length of daylight hours (peas, buckwheat, etc.).
On the basis of photoperiodism in plants and animals in the process of evolution, specific changes in the intensity of physiological processes, periods of growth and reproduction have been developed, repeating with a yearly periodicity, which are called seasonal rhythms. Having studied the patterns of daily rhythms associated with the change of day and night, and seasonal rhythms, a person uses this knowledge for year-round growing vegetables, flowers, birds in artificial conditions, increasing the egg production of chickens, etc.
Daily rhythm in plants is manifested in the periodic opening and closing of flowers (cotton, flax, fragrant tobacco), strengthening or weakening of the physiological and biochemical processes of photosynthesis, the rate of cell division, etc. Daily rhythms, manifested in the periodic alternation of activity and rest, are characteristic of animals and person. All animals can be divided into diurnal and nocturnal. Most of them are most active during the day, and only a few (bats, owls, fruit bats, etc.) have adapted to life only at night. A number of animals constantly live in complete darkness (roundworm, mole, etc.).
Experience the cumulative effect of various conditions. Abiotic factors, biotic factors and anthropogenic affect the features of their life and adaptation.
What are environmental factors?
All conditions of inanimate nature are called abiotic factors. This is, for example, the amount of solar radiation or moisture. Biotic factors include all types of interaction between living organisms. In recent years, human activity has an increasing influence on living organisms. This factor is anthropogenic.
Abiotic environmental factors
The action of factors of inanimate nature depends on the climatic conditions of the habitat. One of them is sunlight. The intensity of photosynthesis, and hence the saturation of air with oxygen, depends on its quantity. It is this substance that living organisms need for respiration.
Abiotic factors also include temperature and air humidity. The species diversity and the growing season of plants, the features of the life cycle of animals depend on them. Living organisms adapt to these factors in different ways. For example, most angiosperms shed their leaves for the winter to avoid excessive moisture loss. Desert plants have which reaches considerable depths. This provides them with the necessary amount of moisture. Primroses have time to grow and bloom in a few spring weeks. And the period of dry summer and cold winter with little snow they experience underground in the form of an onion. This underground modification of the shoot accumulates a sufficient amount of water and nutrients.
Abiotic environmental factors also involve the influence of local factors on living organisms. These include the nature of the relief, the chemical composition and saturation of soils with humus, the level of salinity of the water, the nature of ocean currents, the direction and speed of the wind, and the direction of radiation. Their influence manifests itself both directly and indirectly. Thus, the nature of the relief determines the effect of winds, moisture and illumination.
Influence of abiotic factors
Factors of inanimate nature have a different nature of the impact on living organisms. Monodominant is the impact of one predominant influence with a slight manifestation of the rest. For example, if there is not enough nitrogen in the soil, the root system develops at an insufficient level and other elements cannot influence its development.
Strengthening the action of several factors at the same time is a manifestation of synergy. So, if there is enough moisture in the soil, plants begin to absorb both nitrogen and solar radiation better. Abiotic factors, biotic factors and anthropogenic factors can be provocative. With an early onset of the thaw, the plants will most likely suffer from frost.
Features of the action of biotic factors
Biotic factors include various forms of influence of living organisms on each other. They can also be direct and indirect and appear quite polar. In certain cases organisms have no effect. This is a typical manifestation of neutralism. This rare phenomenon is considered only in the absence of direct interaction of organisms with each other. Living in a common biogeocenosis, squirrels and moose do not interact in any way. However, they are affected by the general quantitative ratio in the biological system.
Examples of biotic factors
Commensalism is also a biotic factor. For example, when deer carry burdock fruits, they do not receive any benefit or harm from this. At the same time, they bring significant benefits, settling many types of plants.
Between organisms often arise and Their examples are mutualism and symbiosis. In the first case, there is a mutually beneficial cohabitation of organisms of different species. A typical example of mutualism is the hermit crab and anemone. Its predatory flower is a reliable defense of the arthropod. And the sea anemone shell is used as a dwelling.
A closer mutually beneficial cohabitation is symbiosis. Its classic example is lichens. This group of organisms is a collection of filaments of fungi and cells of blue-green algae.
Biotic factors, examples of which we have considered, can be supplemented with predation. In this type of interaction, organisms of one species are food for others. In one case, predators attack, kill and eat their prey. In another, they are engaged in the search for organisms of certain species.
Action of anthropogenic factors
Abiotic factors, biotic factors have long been the only ones that affect living organisms. However, with the development of human society, its influence on nature increased more and more. The famous scientist V. I. Vernadsky even singled out a separate shell created by human activity, which he called the Noosphere. Deforestation, unlimited plowing of land, the extermination of many species of plants and animals, unreasonable use of natural resources are the main factors that change the environment.
Habitat and its factors
The biotic factors, examples of which have been given, along with other groups and forms of influences, have their own significance in different habitats. Ground-air vital activity of organisms largely depends on fluctuations in air temperature. And in water, the same indicator is not so important. The action of the anthropogenic factor at the moment is of particular importance in all habitats of other living organisms.
and adaptation of organisms
A separate group can be identified factors that limit the vital activity of organisms. They are called limiting or limiting. For deciduous plants, abiotic factors include the amount of solar radiation and moisture. They are limiting. In the aquatic environment, its salinity level and chemical composition are limiting. So global warming leads to the melting of glaciers. In turn, this entails an increase in the content of fresh water and a decrease in its salinity. As a result, plant and animal organisms that cannot adapt to changes in this factor and adapt inevitably die. At the moment, this is a global environmental problem of mankind.
So, abiotic factors, biotic factors and anthropogenic factors together act on different groups of living organisms in habitats, regulating their numbers and life processes, changing the species richness of the planet.
Test "Abiotic environmental factors"
1. Signal for the beginning of the autumn migration of insectivorous birds:
1) lowering the ambient temperature
2) reduction of daylight hours
3) lack of food
4) increasing humidity and pressure
2. The number of squirrels in the forest zone is NOT affected by:
1) change of cold and warm winters
2) harvest of spruce cones
3) the number of predators
3. Abiotic factors include:
1) competition of plants for the absorption of light
2) the influence of plants on animal life
3) temperature change during the day
4) human pollution
4. The factor limiting the growth of herbaceous plants in a spruce forest is a disadvantage:
4) minerals
5. What is the name of a factor that deviates significantly from the optimal value for the species:
1) abiotic
2) biotic
3) anthropogenic
4) limiting
6. The signal for the onset of leaf fall in plants is:
1) increase in the humidity of the environment
2) reduction in the length of daylight hours
3) decrease in the humidity of the environment
4) increase in the temperature of the environment
7. Wind, precipitation, dust storms are factors:
1) anthropogenic
2) biotic
3) abiotic
4) limiting
8. The reaction of organisms to a change in the length of daylight hours is called:
1) microevolutionary changes
2) photoperiodism
3) phototropism
4) unconditioned reflex
9. Abiotic environmental factors include:
1) undermining the roots by boars
2) locust invasion
3) the formation of bird colonies
4) heavy snowfall
10. Of the listed phenomena, daily biorhythms include:
1) migration of marine fish for spawning
2) opening and closing of flowers of angiosperms
3) bud break in trees and shrubs
4) opening and closing shells in mollusks
11. What factor limits the life of plants in the steppe zone?
1) high temperature
2) lack of moisture
3) no humus
4) excess ultraviolet rays
12. The most important abiotic factor mineralizing organic residues in the biogeocenosis of the forest are:
1) frost
13. The abiotic factors that determine the population size include:
1) interspecific competition
3) decrease in fertility
4) humidity
14. The main limiting factor for plant life in the Indian Ocean is the lack of:
3) mineral salts
4) organic matter
15. Abiotic environmental factors include:
1) soil fertility
2) a wide variety of plants
3) the presence of predators
4) air temperature
16. The reaction of organisms to the length of the day is called:
1) phototropism
2) heliotropism
3) photoperiodism
4) phototaxis
17. Which of the factors regulates seasonal phenomena in the life of plants and animals?
1) temperature change
2) air humidity level
3) the presence of shelter
4) length of day and night
Answers: 1 – 2; 2 – 1; 3 – 3; 4 – 1; 5 – 4;
6 – 2; 7 – 3; 8 – 2; 9 – 4; 10 – 2; 11 – 2;
12 – 2; 13 – 4; 14 – 1; 15 – 4; 16 – 3;
17 – 4; 18 – 4; 19 – 1; 20 – 4; 21 – 2.
18. Which of the following factors of inanimate nature most significantly affects the distribution of amphibians?
3) air pressure
4) humidity
19. Cultivated plants do not grow well on waterlogged soil, as in it:
1) insufficient oxygen content
2) methane is formed
3) excess content of organic matter
4) contains a lot of peat
20. What adaptation contributes to the cooling of plants when the air temperature rises?
1) decrease in metabolic rate
2) increase in the intensity of photosynthesis
3) decrease in the intensity of breathing
4) increased water evaporation
21. What adaptation in shade-tolerant plants provides more efficient and complete absorption of sunlight?
1) small leaves
2) large leaves
3) thorns and thorns
4) wax coating on the leaves
1) Radiant energy from the sun
Solar energy is the main source of energy on Earth, the basis for the existence of living organisms (the process of photosynthesis).
The amount of energy at the Earth's surface is -21 * 10 kJ (solar constant) - at the equator. Decreases towards the poles by about 2.5 times. Also, the amount of solar energy depends on the period of the year, the length of the day, the transparency of the atmospheric air (the more dust, the less solar energy). On the basis of the radiation regime, climatic zones (tundra, forests, deserts, etc.) are distinguished (solar radiation).
2) Lighting
It is determined by the annual total solar radiation, geographical factors (the state of the atmosphere, the nature of the relief, etc.). Light is necessary for the process of photosynthesis, determines the timing of flowering and fruiting of plants. Plants are divided into:
photophilous - plants of open, well-lit places.
shade-loving - the lower tiers of forests (green moss, lichen).
heat-tolerant - grow well in the light, but also tolerate shading. Easily adapt to light conditions.
For animals, the light regime is not such a necessary ecological factor, but it is necessary for orientation in space. Therefore, different animals have different eye designs. In invertebrates it is the most primitive, in others it is very complex. The permanent inhabitants of the caves may be absent. Rattlesnakes see the infrared part of the spectrum, so they hunt at night.
3) Temperature
One of the most important abiotic factors that directly or indirectly affects living organisms.
Temperature directly affects the vital activity of plants and animals, determining their activity and the nature of existence in specific situations. t has a particularly noticeable effect on photosynthesis, metabolism, food intake, motor activity and reproduction. For example, in potatoes, the maximum productivity of photosynthesis is at +20°C, and at t = 48°C it completely stops.
Depending on the nature of heat exchange with the external environment, organisms are divided into:
Organisms, body t = t env. environment, i.e. varies depending on t env. environment, there is no thermoregulation mechanism (effective) (plants, fish, reptiles...). Plants reduce t due to intensive evaporation, with sufficient water supply in the desert, t of leaves decreases by 15 ° C.
Organisms with constant body t (mammals, birds), higher metabolic rate. There is a heat-insulating layer (fur, feathers, fat), t =36-40°C.
Organisms with a constant t (hedgehog, badger, bear), the period of activity - const t of the body, hibernation - is significantly reduced (low energy losses).
There are also organisms that can tolerate fluctuations in t0 over a wide range (lichens, mammals, northern birds) and organisms that exist only at certain t0 (deep-sea organisms, polar ice algae).
4) Humidity of atmospheric air
The lower layers of the atmosphere are the richest in moisture (up to a height of 2 km), where up to 50 of all moisture is concentrated, the amount of water vapor contained in the air depends on the t of the air.
5) Precipitation
This is rain, snow, hail, etc. Precipitation determines the movement and distribution of harmful substances in the environment. In the general circulation of water, it is precipitation that is most mobile, because The amount of moisture in the atmosphere changes 40 times a year. The main conditions for the occurrence of precipitation are: t air, air movement, relief.
There are the following zones in the distribution of precipitation over the earth's surface:
Wet equatorial. Precipitation more than 2000 mm / year, for example, the Amazon, Congo river basins. The maximum amount of precipitation - 11684 mm / year - about. Kauan (Hawaii), 350 days a year rain. Here are located moist equatorial forests - the richest type of vegetation (more than 50 thousand species).
Dry zone of the tropics. Precipitation is less than 200 mm/year. Sahara desert, etc. The minimum amount of precipitation is 0.8 mm / year - the Atacama Desert (Chile, South America).
Humid zone of temperate latitudes. Precipitation is more than 500 mm/year. Forest zone of Europe and North America, Siberia.
polar region. Low precipitation up to 250 mm/year (low air t, low evaporation). Arctic deserts with poor vegetation.
6) Gas composition of the atmosphere
Its composition is practically constant and includes: N -78%, 0 -20.9%, CO, argon and other gases, water particles, dust.
7) Movement of air masses (wind)
The maximum wind speed is approximately 400 km / h - a hurricane (New Hampshire, USA).
Wind pressure - the direction of the wind in the direction of lower pressure. Wind carries impurities in the atmosphere.
8) Atmospheric pressure
760 mmHg or 10 kPa.
1. Light. The radiant energy coming from the Sun is distributed over the spectra as follows. The visible part of the spectrum with a wavelength of 400-750 nm accounts for 48% of solar radiation. The most important role for photosynthesis is played by orange-red rays, which account for 45% of solar radiation. Infrared rays with a wavelength of more than 750 nm are not perceived by many animals and plants, but are necessary sources of thermal energy. The ultraviolet part of the spectrum - less than 400 nm - accounts for 7% of solar energy.
2. Ionizing radiation - it is very high energy radiation capable of knocking electrons out of atoms and attaching them to other atoms to form pairs of positive and negative ions. The source of ionizing radiation is radioactive substances and cosmic rays. During the year, a person on average receives a dose of 0.1 rem and, consequently, for a lifetime (on average 70 years) 7 rem.
3. Humidity of atmospheric air - parameter characterizing the process of its saturation with water vapor. The difference between the maximum (limiting) saturation and this saturation is called the moisture deficit. The higher the deficit, the drier and warmer, and vice versa. Desert plants adapt to economical use of moisture. They have long roots and reduced leaf surface. Desert animals are capable of fast and sustained running for long watering routes. Their internal source of water is fat, the oxidation of 100 g of which produces 100 g of water.
4. Precipitation are the result of water vapor condensation. They play an important role in the water cycle on Earth. Depending on the nature of their precipitation, humid (wet) and arid (dry) zones are distinguished.
5. Gas composition of the atmosphere. The most important biogenic element of the atmosphere, which is involved in the formation of proteins in the body, is nitrogen. Oxygen, which enters the atmosphere mainly from green plants, provides respiration. Carbon dioxide is a natural damper of solar and return terrestrial radiation. Ozone plays a shielding role in relation to the ultraviolet part of the solar spectrum.
6.Temperature on the Earth's surface is determined by the temperature regime of the atmosphere and is closely related to solar radiation. For most terrestrial animals and plants, the optimum temperature ranges from 15 to 30°C. Some shellfish live in hot springs at temperatures up to 53°C, and some blue-green algae and bacteria live up to 70-90°C. Deep cooling causes a complete cessation of life in insects, some fish and reptiles - suspended animation. So, in winter, crucian carp freezes into silt, and in spring it thaws and continues its normal life. In animals with a constant body temperature, in birds and mammals, the state of suspended animation does not occur. Birds grow down in cold times, while mammals have a thick undercoat. Animals that do not have enough food in winter hibernate (bats, ground squirrels, badgers, bears).
Natural resources- natural resources: the bodies and forces of nature, which at a given level of development of productive forces and knowledge can be used to meet the needs of human society. A set of objects and systems of living and non-living nature, components of the natural environment that surround a person and which are used in the process of social production to meet the material and cultural needs of a person and society
natural resources can be inexhaustible And exhaustible. Inexhaustible resources do not end, and exhaustible ones end as they are developed and (or) for other reasons
Origin:
Resources of natural components (mineral, climatic, water, plant, soil, animal world)
Resources of natural-territorial complexes (mining, water management, residential, forestry)
By type of economic use:
Resources of industrial production
Energy resources (combustible minerals, hydropower resources, biofuels, nuclear raw materials)
Non-energy resources (mineral, water, land, forest, fish resources)
Resources of agricultural production (agro-climatic, land and soil, plant resources - fodder base, irrigation water, watering and maintenance)
By type of exhaustion:
· Exhaustible
· Non-renewable (mineral, land resources);
· Renewable (resources of flora and fauna);
· Not fully renewable - the recovery rate is below the level of economic consumption (arable soils, mature forests, regional water resources);
· Inexhaustible resources (water, climate).
By degree of substitution:
· Irreplaceable;
· Interchangeable.
By usage criteria:
· Industrial (industrial, agricultural);
· Potentially promising;
· Recreational (natural complexes and their components, cultural and historical sights, economic potential of the territory).
ecological crisis- violation of the balance between natural conditions and human impact on the environment.
Fighting a global environmental crisis is much more difficult than dealing with a local one. The solution to this problem can only be achieved by minimizing the pollution produced by mankind to a level that ecosystems will be able to cope with on their own. The current global environmental crisis includes four main components: acid rain, the greenhouse effect, pollution of the planet with superecotoxicants and the so-called ozone holes.
Similar information.
abiotic factors. The abiotic factors of the terrestrial environment primarily include climatic factors
The abiotic factors of the terrestrial environment primarily include climatic factors. Let's consider the main ones.
1. Light or solar radiation. The biological effect of sunlight depends on its intensity, duration of action, spectral composition, daily and seasonal periodicity.
The radiant energy coming from the Sun propagates in space in the form of electromagnetic waves: ultraviolet rays (wavelength l< 0,4 мкм), видимые лучи (l = 0,4 ¸ 0,75 мкм) и инфракрасные лучи (l >0.75 µm).
Ultraviolet rays are characterized by the highest quantum energy and high photochemical activity. In animals, they contribute to the formation of vitamin D and the synthesis of pigments by skin cells, in plants they have a shaping effect and contribute to the synthesis of biologically active compounds. Ultraviolet radiation with a wavelength of less than 0.29 microns is detrimental to all living things. However, thanks to the ozone screen, only a small part of it reaches the Earth's surface.
The visible part of the spectrum is of particular importance for organisms. Thanks to visible light, plants formed the apparatus of photosynthesis. For animals, the light factor is primarily a necessary condition for orientation in space and time, and also participates in the regulation of many vital processes.
Infrared radiation increases the temperature of the natural environment and the organisms themselves, which is especially important for cold-blooded animals. In plants, infrared rays play a significant role in transpiration (evaporation of water from the surface of the leaves ensures the removal of excess heat) and contribute to the absorption of carbon dioxide by plants.
2. Temperature affects all vital processes. First of all, it determines the speed and nature of the course of metabolic reactions in organisms.
The optimum temperature factor for most organisms is within 15 ¸ 30 0 С, however, some living organisms withstand its significant fluctuations. For example, certain types of bacteria and blue-green algae can exist in hot springs at a temperature of about 80 0 C. Polar waters with temperatures from 0 to -2 0 C are inhabited by various representatives of the flora and fauna.
3. Humidity atmospheric air is associated with its saturation with water vapor. Seasonal and diurnal fluctuations in humidity, along with light and temperature, regulate the activity of organisms.
In addition to climatic factors, important for living organisms is gas composition of the atmosphere. It is relatively constant. The atmosphere consists mainly of nitrogen and oxygen with small amounts of carbon dioxide, argon and other gases. Nitrogen is involved in the formation of protein structures of organisms, oxygen provides oxidative processes.
Abiotic factors of the aquatic environment are:
1 - density, viscosity, mobility of water;
