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What environmental factors are abiotic. Air environment and its gas composition

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.).

Constantly evolving, humanity does not particularly think about how abiotic factors directly or indirectly affect a person. What are abiotic conditions and why is their seemingly imperceptible influence so important to consider? These are certain physical phenomena that are not related to wildlife, which in one way or another affect the life or environment of a person. Roughly speaking, light, the degree of humidity, the Earth's magnetic field, temperature, the air we breathe - all these parameters are called abiotic. Under this definition does not fall in any way the influence of living organisms, including bacteria, microorganisms and even protozoa.

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Examples and types

We have already found out that this is a set of phenomena of inanimate nature, which can be climatic, water or soil. The classification of abiotic factors is conditionally divided into three types:

Chemical,
physical,
Mechanical.

The chemical influence is exerted by the organic and mineral composition of the soil, atmospheric air, groundwater and other waters. The physical ones include natural light, pressure, temperature and humidity of the environment. Accordingly, cyclones, solar activity, soil, air and water movement in nature are considered mechanical factors. The combination of all these parameters has a tremendous impact on the reproduction, distribution and quality of life of all life on our planet. And if a modern person thinks that all these phenomena that literally control the life of his ancient ancestors have now been tamed with the help of advanced technologies, then, unfortunately, this is not at all the case.

One should not lose sight of biotic factors and processes that are inevitably tied to the abiotic influence on all living things. Biotic are the forms of influence of living organisms on each other, almost any of them is caused by abiotic environmental factors and their influence on living organisms.

What influence can the factors of inanimate nature have?

To begin with, it is necessary to indicate what falls under the definition of abiotic environmental factors? Which of the parameters can be attributed here? The abiotic environmental factors include: light, temperature, humidity, and the state of the atmosphere. Let's consider which factor influences how in more detail.

Light

Light is one of the environmental factors that literally every object in geobotany uses. Sunlight is the most important source of thermal energy, responsible in nature for the processes of development, growth, photosynthesis and many, many others.

Light, as an abiotic factor, has a number of specific characteristics: spectral composition, intensity, periodicity. These abiotic conditions are most important for plants whose main life is the process of photosynthesis. Without a high-quality spectrum and good lighting intensity, the plant world will not be able to actively reproduce and grow fully. The duration of light exposure is also important, so, with a short daylight, plant growth is significantly reduced, and reproduction functions are inhibited. Not in vain, for good growth and harvest, in greenhouse (artificial) conditions, they necessarily create the longest possible light period, which is so necessary for plant life. In such cases, natural biological rhythms are drastically and deliberately violated. Lighting is the most important natural factor for our planet.

Temperature

Temperature is also one of the most powerful abiotic factors. Without the right temperature regime, life on Earth is really impossible - and this is not an exaggeration. Moreover, if a person can deliberately maintain the light balance at a certain level, and it is quite simple to do this, then the situation with temperature is much more difficult.

Of course, over the millions of years of existence on the planet, both plants and animals have adapted to the temperature that is uncomfortable for them. The processes of thermoregulation are different here. For example, in plants, two methods are distinguished: physiological, namely, an increase in the concentration of cell sap, due to the intensive accumulation of sugar in cells. Such a process provides the necessary level of frost resistance of plants, at which they can not die even at very low temperatures. The second way is physical, it consists in the special structure of foliage or its reduction, as well as growth methods - squat or creeping along the ground - to avoid freezing in open space.

Among animals, eurytherms are distinguished - those that freely exist with a significant temperature fluctuation, and stenotherms, for whose life a certain temperature range of not too large size is important. Eurythermal organisms exist when the ambient temperature fluctuates within 40-50 degrees, usually these are conditions close to the continental climate. High temperatures in summer, frost in winter.

A striking example of a eurythermal animal can be considered a hare. In the warm season, he feels comfortable in the heat, and in frosts, turning into a hare, he perfectly adapts to the temperature abiotic factors of the environment and their effect on living organisms.

There are also many representatives of the fauna - these are animals, and insects, and mammals that have a different type of thermoregulation - with the help of a state of torpor. In this case, the metabolism slows down, but the body temperature can be kept at the same level. Example: for a brown bear, the abiotic factor is winter air temperature, and its method of adapting to frost is hibernation.

Air

The abiotic environmental factors also include the air environment. In the process of evolution, living organisms had to master the air habitat after leaving the water on land. Some of them, especially this was reflected in insects and birds, in the process of development of land-moving species, adapted to air movement, having mastered the technique of flight.

The process of ansmochory should not be excluded - the migration of plant species with the help of air currents - the vast majority of plants populated the territories in which they now grow in this way, by pollination, seed transfer by birds, insects, and the like.

If you ask yourself what abiotic factors affect the flora and fauna, then the atmosphere, in terms of its influence, will clearly not be in last place - its role in the process of evolution, development and population size cannot be exaggerated.

However, it is not the air itself that is important, as a parameter that affects nature and organisms, but also its quality, namely, its chemical composition. What factors are important in this aspect? There are two of them: oxygen and carbon dioxide.

Importance of oxygen

Without oxygen, only anaerobic bacteria can exist; other living organisms need it to an extreme degree. The oxygen component of the air environment refers to those types of products that are only consumed, but only green plants are capable of producing oxygen, by photosynthesis.

Oxygen, entering the body of a mammal, is bound into a chemical compound by hemoglobin in the blood and, in this form, is transferred with the blood to all cells and organs. This process ensures the normal functioning of any living organism. The influence of the air environment on the process of life support is great and continuous throughout life.

Importance of carbon dioxide

Carbon dioxide is a product exhaled by mammals and some plants, it is also formed in the process of combustion and vital activity of soil microorganisms. However, all these natural processes emit such an insignificant amount of carbon dioxide that they cannot even be compared with a real ecosystem disaster that is directly and indirectly related to all natural processes - industrial emissions and products of technological processes. And, if some hundred years ago, a similar problem would be mainly observed in a large industrial city, such as, for example, Chelyabinsk, then today, it is spread almost throughout the entire planet. In our time, carbon dioxide, produced everywhere: enterprises, vehicles, various devices, stubbornly expands the group of its impact, including the atmosphere.

Humidity

Humidity, as an abiotic factor, is the water content of whatever it is: plant, air, soil, or living organism. Of the environmental factors, it is humidity that is the first condition necessary for the origin and development of life on Earth.

All living things on the planet need water. The mere fact that any living cell is eighty percent water speaks for itself. And for many living beings, the ideal conditions for the habitat of the natural environment are precisely water bodies or a humid climate.

Wettest place on earth Urek (Bioko Island, Equatorial Guinea)

Of course, there are also types of areas where the amount of water is minimal or it is present with any periodicity, these are desert, high mountain relief, and the like. This has an obvious effect on nature: the absence or minimum of vegetation, drying soil, no fruit-bearing plants, only those types of flora and fauna survive that can adapt to such conditions. Fitness, to whatever extent it is expressed, is not lifelong and, in the case when the characteristics of abiotic factors change for some reason, it can also change or disappear altogether.

In terms of the degree of influence on nature, humidity is important to take into account not only as a single parameter, but also in combination with each of the listed factors, since together they form the type of climate. Each specific territory with its own abiotic environmental factors has its own characteristics, its own vegetation, species and population size.

The influence of abiotic factors on humans

Man, as a component of an ecosystem, also applies to objects that are influenced by abiotic factors of inanimate nature. The dependence of human health and behavior on solar activity, the lunar cycle, cyclones and similar influences was noted several centuries ago, thanks to the observation of our ancestors. And in modern society, the presence of a group of people is invariably fixed, the changes in mood and well-being of which are indirectly affected by abiotic environmental factors.

For example, studies of solar influence have shown that this star has an eleven-year cycle of periodic activity. On this basis, fluctuations in the electromagnetic field of the Earth occur, which affects the human body. Peaks of solar activity can weaken the immune system, and pathogenic microorganisms, on the contrary, make them more tenacious and adapted to widespread distribution within the community. The sad consequences of such a process are outbreaks of epidemics, the emergence of new mutations and viruses.

Epidemic of unknown infection in India

Another important example of abiotic influence is ultraviolet. Everyone knows that in certain doses, this type of radiation is even useful. This environmental factor has an antibacterial effect, slows down the development of spores that cause skin diseases. But in high doses, ultraviolet radiation negatively affects the population, causing such deadly diseases as cancer, leukemia or sarcoma.

The manifestations of the action of abiotic environmental factors on a person directly include temperature, pressure and humidity, in short - climate. An increase in temperature will lead to inhibition of physical activity and the development of problems with the cardiovascular system. Low temperatures are dangerous hypothermia, which means inflammation of the respiratory system, joints and limbs. It should be noted here that the humidity parameter further enhances the influence of the temperature regime.

An increase in atmospheric pressure threatens the health of owners of weak joints and fragile blood vessels. Especially dangerous, there are sharp changes in this climatic parameter - sudden hypoxia, blockage of capillaries, fainting and even coma can occur.

Of the environmental factors, one should also note the chemical aspect of the impact on humans. These include all chemical elements contained in water, atmosphere or soil. There is the concept of regional factors - the excess or, conversely, the lack of certain compounds or trace elements in the nature of each individual region. For example, from the listed factors, both a lack of fluorine is harmful - it causes damage to tooth enamel, and its excess - it accelerates the process of ossification of the ligaments, disrupts the functioning of some internal organs. Fluctuations in the content of such chemical elements as chromium, calcium, iodine, zinc, and lead are especially noticeable in the incidence rate of the population.

Of course, many of the abiotic conditions listed above, although they are abiotic factors of the natural environment, are in fact very much dependent on human activity - the development of mines and deposits, changes in river beds, the air environment, and similar examples of the intervention of progress in natural phenomena.

Detailed characteristics of abiotic factors

Why is the impact on the population of most abiotic factors so huge? This is logical: after all, to ensure the life cycle of any living organism on Earth, the totality of all parameters that affect the quality of life, its duration, which determines the number of ecosystem objects, is important. Lighting, composition of the atmosphere, humidity, temperature, zoning of the distribution of representatives of wildlife, salinity of water and air, its edaphic data are the most important abiotic factors and adaptation of organisms to them is positive or negative, but in any case, it is inevitable. It is easy to verify this: just look around!

Abiotic factors of the aquatic environment provide the origin of life, make up three-quarters of every living cell on Earth. In the forest ecosystem, biotic factors include all the same parameters: humidity, temperature, soil, light - they determine the type of forest, saturation with plants, their adaptability to a particular region.

In addition to the obvious, already listed, important abiotic factors of the natural environment should also be called salinity, soil and the Earth's electromagnetic field. The entire ecosystem has evolved for hundreds of years, the terrain has changed, the degree of adaptation of living organisms to certain living conditions, new species have appeared and entire populations have migrated. However, this natural chain has long been violated by the fruits of human activity on the planet. The work of environmental factors is fundamentally disrupted due to the fact that the impact of abiotic parameters does not occur purposefully, as factors of inanimate nature, but already as a harmful effect on the development of organisms.

Unfortunately, the influence of abiotic factors on the quality and life expectancy of a person and humanity as a whole has been and remains enormous and can have both positive and negative consequences for each individual organism for all of humanity as a whole.

Abiotic environmental factors include the substrate and its composition, humidity, light and other types of radiation in nature, and its composition, and microclimate. It should be noted that temperature, air composition, humidity and light can be conditionally referred to as "individual", and the substrate, climate, microclimate, etc. - to "complex" factors.

The substrate (literally) is the place of attachment. For example, for woody and herbaceous forms of plants, for soil microorganisms, this is the soil. In some cases, the substrate can be considered a synonym for habitat (for example, soil is an edaphic habitat). The substrate is characterized by a certain chemical composition that affects organisms. If the substrate is understood as a habitat, then in this case it is a complex of biotic and abiotic factors characteristic of it, to which one or another organism adapts.

Characteristics of temperature as an abiotic environmental factor

Temperature is an environmental factor associated with the average kinetic energy of particles and expressed in degrees of various scales. The most common is the scale in degrees Celsius (°C), which is based on the amount of expansion of water (the boiling point of water is 100°C). In SI, an absolute temperature scale is adopted, for which the boiling point of water is T kip. water = 373 K.

Very often, temperature is a limiting factor that determines the possibility (impossibility) of living organisms in a particular habitat.

According to the nature of body temperature a, all organisms are divided into two groups: poikilothermic (their body temperature depends on the ambient temperature and is almost the same as the ambient temperature) and homoiothermic (their body temperature does not depend on the ambient temperature and is more or less constant: if it fluctuates, then within small limits - fractions of a degree).

Poikilotherms include plant organisms, bacteria, viruses, fungi, unicellular animals, as well as animals with a relatively low level of organization (fish, arthropods, etc.).

Homeotherms include birds and mammals, including humans. A constant body temperature reduces the dependence of organisms on the temperature of the external environment, makes it possible to settle in a larger number of ecological niches, both in latitudinal and vertical distribution around the planet. However, in addition to homoiothermy, organisms develop adaptations to overcome the effects of low temperatures.

According to the nature of the transfer of low temperatures, plants are divided into heat-loving and cold-resistant. The heat-loving plants include plants of the south (bananas, palm trees, southern varieties of apple trees, pears, peaches, grapes, etc.). Cold-resistant plants include plants of middle and northern latitudes, as well as plants growing high in the mountains (for example, mosses, lichens, pine, spruce, fir, rye, etc.). In central Russia, varieties of frost-resistant fruit trees are grown, which are specially bred by breeders. The first great successes in this area were achieved by I. V. Michurin and other folk breeders.

The norm of the body's reaction to the temperature factor (for individual organisms) is often narrow, i.e. a particular organism can function normally in a fairly narrow temperature range. Thus, marine vertebrates die when the temperature rises to 30-32°C. But for living matter as a whole, the boundaries of the temperature effect at which life is preserved are very wide. So, in California, a species of fish lives in hot springs, functioning normally at a temperature of 52 ° C, and heat-resistant bacteria that live in geysers can withstand temperatures up to 80 ° C (this is the “normal” temperature for them). In glaciers at a temperature of -44 ° C, some live, etc.

The role of temperature as an environmental factor comes down to the fact that it affects metabolism: at low temperatures, the rate of bioorganic reactions slows down greatly, and at high temperatures it increases significantly, which leads to an imbalance in the course of biochemical processes, and this causes various diseases, and sometimes and lethal outcome.

The effect of temperature on plant organisms

Temperature is not only a factor determining the possibility of plant habitation in a particular area, but for some plants it affects the process of their development. Thus, winter varieties of wheat and rye, which did not undergo the process of “vernalization” (low temperatures) during germination, do not produce seeds when they grow in the most favorable conditions.

Plants have various adaptations to withstand exposure to low temperatures.

1. In winter, the cytoplasm loses water and accumulates substances that have the effect of "antifreeze" (these are monosaccharides, glycerin and other substances) - concentrated solutions of such substances freeze only at low temperatures.

2. The transition of plants to a stage (phase) resistant to low temperatures - the stage of spores, seeds, tubers, bulbs, rhizomes, root crops, etc. Woody and shrubby forms of plants shed their leaves, the stems are covered with cork, which has high thermal insulation properties, and antifreeze substances accumulate in living cells.

The effect of temperature on animal organisms

Temperature affects poikilothermic and homeothermic animals differently.

Poikilothermic animals are active only during the period of optimal temperatures for their vital activity. During the period of low temperatures, they fall into hibernation (amphibians, reptiles, arthropods, etc.). Some insects overwinter either as eggs or as pupae. The hibernation of an organism is characterized by a state of anabiosis, in which metabolic processes are very strongly inhibited and the body can go without food for a long time. Poikilothermic animals can also hibernate under the influence of high temperatures. So, animals in the lower latitudes in the hot time of the day are in holes, and the period of their active life falls on the early morning or late evening (or they are nocturnal).

Animal organisms fall into hibernation not only due to the influence of temperature, but also due to other factors. So, a bear (a homeothermic animal) hibernates in winter due to a lack of food.

Homoiothermic animals to a lesser extent depend on temperature in their life, but temperature affects them in terms of the presence (absence) of food supply. These animals have the following adaptations to overcome the effects of low temperatures:

1) animals move from colder to warmer regions (bird migration, mammal migration);

2) change the nature of the cover (summer fur or plumage is replaced by a thicker winter one; they accumulate a large layer of fat - wild pigs, seals, etc.);

3) hibernate (for example, a bear).

Homeothermic animals have adaptations to reduce exposure to temperatures (both high and low). So, a person has sweat glands that change the nature of secretion at elevated temperatures (the amount of secretion increases), the lumen of blood vessels in the skin changes (at low temperatures it decreases, and at high temperatures it increases), etc.

Radiation as an abiotic factor

Both in the life of plants and in the life of animals, a huge role is played by various radiations that either enter the planet from the outside (solar rays) or are released from the bowels of the Earth. Here we consider mainly solar radiation.

Solar radiation is heterogeneous and consists of electromagnetic waves of different lengths, and therefore, they also have different energies. The Earth's surface reaches the rays of both the visible and invisible spectrum. The invisible spectrum includes infrared and ultraviolet rays, while the visible spectrum has seven of the most distinguishable rays (from red to violet). radiation quanta increases from infrared to ultraviolet (i.e., ultraviolet rays contain quanta of the shortest waves and the highest energy).

The sun's rays have several ecologically important functions:

1) due to the sun's rays, a certain temperature regime is realized on the Earth's surface, which has a latitudinal and vertical zonal character;

In the absence of human influence, the composition of the air, however, may differ depending on the height above sea level (with height, the content of oxygen and carbon dioxide decreases, since these gases are heavier than nitrogen). The air of coastal areas is enriched with water vapor, which contains sea salts in a dissolved state. The air of the forest differs from the air of the fields with impurities of compounds secreted by various plants (for example, the air of a pine forest contains a large amount of resinous substances and ethers that kill pathogens, therefore this air is curative for tuberculosis patients).

Climate is the most important complex abiotic factor.

Climate is a cumulative abiotic factor that includes a certain composition and level of solar radiation, the level of temperature and humidity associated with it, and a certain wind regime. The climate also depends on the nature of the vegetation growing in a given area, and on the terrain.

On Earth, there is a certain latitudinal and vertical climatic zonality. There are humid tropical, subtropical, sharply continental and other types of climate.

Repeat the information about the different types of climate in the textbook of physical geography. Consider the climate of the area where you live.

Climate as a cumulative factor forms one or another type of vegetation (flora) and a closely related type of fauna. Human settlements have a great influence on the climate. The climate of large cities differs from the climate of suburban areas.

Compare the temperature regime of the city where you live and the temperature regime of the area where the city is located.

As a rule, the temperature in the city (especially in the center) is always higher than in the region.

Microclimate is closely related to climate. The reason for the emergence of the microclimate is the differences in the relief in a given territory, the presence of water bodies, which leads to a change in conditions in different territories of this climatic zone. Even in a relatively small area of a summer cottage, in its individual parts, different conditions for the growth of plants may arise due to different lighting conditions.

Abiotic factors are factors space (solar radiation) climatic (light, temperature, humidity, atmospheric pressure, precipitation, air movement), edaphic or soil factors (mechanical composition of the soil, moisture capacity, air permeability, soil density), orographic factors (relief, height above sea level, slope exposure), chemical factors (gas composition of air, salt composition and acidity of water and soil solutions). Abiotic factors affect living organisms (directly or indirectly) through certain aspects of metabolism. Their peculiarity is the one-sidedness of the impact: the body can adapt to them, but does not have a significant effect on them.

I. Space Factors

The biosphere, as a habitat for living organisms, is not isolated from the complex processes taking place in outer space, and not only directly related to the Sun. Cosmic dust, meteoritic matter falls on the Earth. The Earth periodically collides with asteroids, approaches comets. Substances and waves that arise as a result of outbursts of supernovae pass through the Galaxy. Of course, our planet is most closely connected with the processes taking place on the Sun, with the so-called solar activity. The essence of this phenomenon is the transformation of the energy accumulated in the magnetic fields of the Sun into the energy of the movement of gaseous masses, fast particles, and short-wave electromagnetic radiation.

The most intense processes are observed in the centers of activity, called active regions, in which an increase in the magnetic field is observed, regions of increased brightness appear, as well as the so-called sunspots. Explosive energy releases can occur in active regions, accompanied by plasma ejections, the sudden appearance of solar cosmic rays, and an increase in short-wave and radio emission. It is known that changes in the level of flare activity are cyclic in nature with a normal cycle of 22 years, although fluctuations with a frequency of 4.3 to 1850 years are known. Solar activity affects a number of life processes on Earth - from the occurrence of epidemics and bursts of births to major climate transformations. This was shown back in 1915 by the Russian scientist A.L. Chizhevsky, the founder of a new science - heliobiology (from the Greek helios - the Sun), which considers the impact of changes in solar activity on the Earth's biosphere.

Thus, electromagnetic radiation associated with solar activity with a wide range of wavelengths is among the most important cosmic factors. Absorption by the Earth's atmosphere of short-wave radiation leads to the formation of protective shells, in particular the ozonosphere. Among other cosmic factors, the corpuscular radiation of the Sun should be mentioned.

The solar corona (the upper part of the solar atmosphere), consisting mainly of ionized hydrogen atoms - protons - with an admixture of helium, is constantly expanding. Leaving the corona, this flow of hydrogen plasma propagates in the radial direction and reaches the Earth. It is called the solar wind. It fills the entire region of the solar system; and constantly flows around the Earth, interacting with its magnetic field. It is clear that this is due to the dynamics of magnetic activity (for example, magnetic storms) and directly affects life on Earth.

Changes in the ionosphere in the polar regions of the Earth are also associated with solar cosmic rays, which cause ionization. During powerful flares of solar activity, the impact of solar cosmic rays can briefly exceed the usual background of galactic cosmic rays. At present, science has accumulated a lot of factual materials illustrating the influence of cosmic factors on biospheric processes. In particular, the sensitivity of invertebrates to changes in solar activity has been proven, a correlation of its variations with the dynamics of the human nervous and cardiovascular systems, as well as with the dynamics of diseases - hereditary, oncological, infectious, etc., has been established.

Features of the impact on the biosphere from cosmic factors and manifestations of solar activity are that the surface of our planet is separated from the Cosmos by a powerful layer of matter in a gaseous state, i.e., by the atmosphere.

II. climatic factors

The most important climate-forming function belongs to the atmosphere as an environment that perceives cosmic and solar-related factors.

1. Light. The energy of solar radiation propagates in space in the form of electromagnetic waves. About 99% of it is rays with a wavelength of 170-4000 nm, including 48% in the visible part of the spectrum with a wavelength of 400-760 nm, and 45% in the infrared (wavelength from 750 nm to 10 "3 m) , about 7% - to ultraviolet (wavelength less than 400 nm).In the processes of photosynthesis, the most important role is played by photosynthetically active radiation (380-710 nm).

The amount of solar radiation energy coming to the Earth (to the upper boundary of the atmosphere) is almost constant and is estimated at 1370 W/m2. This value is called the solar constant.

Passing through the atmosphere, solar radiation is scattered by gas molecules, suspended impurities (solid and liquid), absorbed by water vapor, ozone, carbon dioxide, dust particles. Scattered solar radiation partially reaches the earth's surface. Its visible part creates light during the day in the absence of direct sunlight, for example, in heavy cloud cover.

The energy of solar radiation is not only absorbed by the Earth's surface, but is also reflected by it in the form of a stream of long-wave radiation. Lighter colored surfaces reflect light more intensely than darker ones. So, pure snow reflects 80-95%, polluted - 40-50, chernozem soil - 5-14, light sand - 35-45, forest canopy - 10-18%. The ratio of solar radiation reflected by the surface to the incoming is called albedo.

The radiant energy of the Sun is associated with the illumination of the earth's surface, which is determined by the duration and intensity of the light flux. Plants and animals in the process of evolution have developed deep physiological, morphological and behavioral adaptations to the dynamics of illumination. All animals, including humans, have so-called circadian (daily) rhythms of activity.

The requirements of organisms for a certain duration of dark and light time are called photoperiodism, and seasonal fluctuations in illumination are especially important. The progressive trend towards a decrease in the length of daylight hours from summer to autumn serves as information to prepare for wintering or hibernation. Since photoperiodic conditions depend on latitude, a number of species (primarily insects) can form geographic races that differ in threshold day length.

2. Temperature

Temperature stratification is a change in water temperature along the depth of a water object. Continuous, temperature change is characteristic of any ecological systems. Often the word "gradient" is used to denote such a change. However, the temperature stratification of water in a reservoir is a specific phenomenon. So, in the summer, surface waters heat up more than deep ones. Since warmer water has a lower density and lower viscosity, its circulation occurs in the surface, heated layer and it does not mix with denser and more viscous cold water. An intermediate zone with a sharp temperature gradient forms between the warm and cold layers, which is called the thermocline. The general temperature regime associated with periodic (annual, seasonal, daily) temperature changes is also the most important condition for the habitat of living organisms in water.

3. Humidity. Humidity is the amount of water vapor in the air. The lower layers of the atmosphere are richest in moisture (up to a height of 1.5-2.0 km), where approximately 50% of all atmospheric moisture is concentrated. The content of water vapor in the air depends on the temperature of the latter.

4. Precipitation is water in liquid (drops) or solid state that falls on the earth. surface from clouds or deposited directly from the air due to condensation of water vapor. Rain, snow, drizzle, freezing rain, snow grains, ice pellets, hail can fall from the clouds. The amount of precipitation is measured by the thickness of the layer of fallen water in millimeters.

Precipitation is closely related to air humidity and is the result of water vapor condensation. Due to condensation in the surface air layer, dews and fogs are formed, and at low temperatures moisture crystallization is observed. Condensation and crystallization of water vapor in the higher layers of the atmosphere form clouds of various structures and are the cause of precipitation. Allocate wet (humid) and dry (arid) zones of the globe. The maximum amount of precipitation falls in the tropical forest zone (up to 2000 mm / year), while in arid zones (for example, in deserts) - 0.18 mm / year.

Atmospheric precipitation is the most important factor influencing the processes of environmental pollution. The presence of water vapor (fog) in the air with the simultaneous entry of, for example, sulfur dioxide into it leads to the fact that the latter turns into sulfurous acid, which is oxidized to sulfuric acid. In conditions of stagnant air (calm), a stable toxic fog is formed. Such substances can be washed out of the atmosphere and deposited on land and ocean surfaces. A typical result is the so-called acid rain. Particulate matter in the atmosphere can serve as nuclei for moisture condensation, causing various forms of precipitation.

5. Atmospheric pressure. Normal pressure is considered to be 101.3 kPa (760 mm Hg). Within the surface of the globe there are areas of high and low pressure, and seasonal and daily minima and pressure maxima are observed at the same points. Marine and continental types of atmospheric pressure dynamics also differ. Periodically occurring areas of low pressure are called cyclones and are characterized by powerful air currents moving in a spiral and moving in space towards the center. Cyclones are associated with unstable weather and high rainfall.

In contrast, anticyclones are characterized by stable weather, low wind speeds, and, in some cases, temperature inversions. During anticyclones, unfavorable meteorological conditions from the point of view of the transfer and dispersion of impurities can occur.

6. Air movement. The reason for the formation of wind currents and the movement of air masses is the uneven heating of different parts of the earth's surface, associated with pressure drops. The wind flow is directed towards lower pressure, but the rotation of the Earth also affects the circulation of air masses on a global scale. In the surface layer of air, the movement of air masses affects all meteorological factors of the environment, i.e. on climate, including temperature, humidity, land and sea evaporation, and plant transpiration.

It is especially important to know that wind flows are the most important factor in the transfer, dispersion and fallout of pollutants entering the atmosphere from industrial enterprises, thermal power plants, and transport. The strength and direction of the wind determine the modes of environmental pollution. For example, a calm in combination with an air temperature inversion is considered as unfavorable meteorological conditions (NMC) that contribute to long-term severe air pollution in areas of industrial enterprises and human habitation.

Are common patterns of distribution of levels and regional regimes of environmental factors

The geographic envelope of the Earth (like the biosphere) is heterogeneous in space, it is differentiated into territories that differ from each other. It is successively divided into physical-geographical zones, geographical zones, intrazonal mountainous and lowland regions and sub-regions, subzones, etc.

The physical-geographical belt is the largest taxonomic unit of the geographical envelope, which is composed of a number of geographical zones that are close in terms of heat balance and moisture regime.

There are, in particular, the Arctic and Antarctic, subarctic and subantarctic, northern and southern temperate and subtropical, subequatorial and equatorial belts.

geographic (aka.–natural, landscape) zone–this is a significant part of the physical-geographical belt with a special nature of geomorphological processes, with special types of climate, vegetation, soils, flora and fauna.

The zones have predominantly (although by no means always) broadly elongated outlines and are characterized by similar natural conditions, a certain sequence depending on the latitudinal position - this is latitudinal geographic zonality, due mainly to the nature of the distribution of solar energy over latitudes, i.e. with a decrease in its arrival from the equator to the poles and uneven moistening.

Along with the latitude, there is also a vertical (or altitudinal) zonality typical of mountainous regions, i.e., a change in vegetation, wildlife, soil, climatic conditions, as you rise from sea level, mainly associated with a change in heat balance: the air temperature difference is 0.6-1.0 °C for every 100 m of height.

III. edaphicor soilfactors

According to the definition of V. R. Williams, the soil is a loose surface horizon of the land, capable of producing a crop of plants. The most important property of the soil is its fertility, i.e. the ability to provide organic and mineral nutrition to plants. Fertility depends on the physical and chemical properties of the soil, which together are edaphogenic (from the Greek. edafos - soil), or edaphic, factors.

1. Mechanical composition of the soil. Soil is a product of physical, chemical and biological transformation (weathering) of rocks; it is a three-phase medium containing solid; liquid and gaseous components. It is formed as a result of complex interactions of climate, plants, animals, microorganisms and is considered as a bio-inert body containing living and non-living components.

There are many types of soils in the world associated with different climatic conditions and the specifics of the processes of their formation. Soils are characterized by a certain zonality, although the belts are by no means always continuous. Among the main types of soils in Russia are tundra, podzolic soils of the taiga-forest zone (the most common), chernozems, gray forest soils, chestnut soils (to the south and east of chernozems), brown soils (characteristic of dry steppes and semi-deserts), red soils, salt marshes, etc.

As a result of the movement and transformation of substances, the soil is usually divided into separate layers, or horizons, the combination of which forms a soil profile on the section (Fig. 2), which in general looks like this:

the uppermost horizon (A 1 ), containing decay products of organic matter, is the most fertile. It is called humus or humus, has a granular-lumpy or layered structure. It is in it that complex physico-chemical processes take place, as a result of which elements of plant nutrition are formed. Humus has a different color.

Above the humus horizon there is a layer of plant litter, which is commonly called the litter (A 0 ). It consists of undecomposed plant remains.

Below the humus horizon there is an infertile whitish layer 10-12 cm thick (A 2). Nutrients are washed out of it with water or acids. Therefore, it is called the leaching or leaching (eluvial) horizon. Actually, it is a podzolic horizon. Quartz and aluminum oxide are weakly dissolved and remain in this horizon.

Even lower lies the parent rock (C).

Environmental factors are all environmental factors acting on the body. They are divided into 3 groups:

The best value of a factor for an organism is called optimal(optimum point), for example, the optimum air temperature for a person is 22º.

Anthropogenic factors

Human influences change the environment too quickly. This leads to the fact that many species become rare and die out. Biodiversity is decreasing because of this.

For example, consequences of deforestation:

The habitat for the inhabitants of the forest (animals, fungi, lichens, grasses) is being destroyed. They may disappear completely (decreased biodiversity).
The forest with its roots holds the top fertile soil layer. Without support, the soil can be blown away by the wind (you get a desert) or water (you get ravines).
The forest evaporates a lot of water from the surface of its leaves. If you remove the forest, then the air humidity in the area will decrease, and the soil moisture will increase (a swamp may form).

1. Choose three options. What anthropogenic factors influence the size of the wild boar population in the forest community?
1) increase in the number of predators
2) shooting animals
3) feeding animals
4) the spread of infectious diseases
5) cutting down trees
6) severe weather in winter

Answer

2. Choose three correct answers from six and write down the numbers under which they are indicated. What anthropogenic factors influence the size of the May lily of the valley population in the forest community?
1) cutting down trees
2) increase in shading

4) collection of wild plants
5) low air temperature in winter
6) trampling the soil

Answer

3. Choose three correct answers from six and write down the numbers under which they are indicated. What processes in nature are classified as anthropogenic factors?
1) ozone depletion
2) daily change in illumination
3) competition in the population
4) accumulation of herbicides in the soil
5) relationship between predators and their prey
6) increased greenhouse effect

Answer

4. Choose three correct answers from six and write down the numbers under which they are indicated. What anthropogenic factors influence the number of plants listed in the Red Book?
1) destruction of their living environment
2) increase in shading
3) lack of moisture in summer
4) expansion of the areas of agrocenoses
5) sudden temperature changes
6) trampling the soil

Answer

5. Choose three correct answers from six and write down the numbers under which they are indicated. Anthropogenic environmental factors include
1) application of organic fertilizers to the soil
2) decrease in illumination in reservoirs with depth
3) precipitation
4) thinning pine seedlings
5) cessation of volcanic activity
6) shallowing of rivers as a result of deforestation

Answer

6. Choose three correct answers from six and write down the numbers under which they are indicated. What environmental disturbances in the biosphere are caused by anthropogenic interference?
1) the destruction of the ozone layer of the atmosphere
2) seasonal changes in the illumination of the land surface
3) decline in the number of cetaceans
4) the accumulation of heavy metals in the bodies of organisms near highways
5) accumulation of humus in the soil as a result of leaf fall
6) accumulation of sedimentary rocks in the depths of the oceans

Answer

1. Establish a correspondence between the example and the group of environmental factors that it illustrates: 1) biotic, 2) abiotic
A) overgrowing of the pond with duckweed
B) increase in the number of fish fry
C) eating fish fry by a swimming beetle
D) ice formation
E) flushing into the river of mineral fertilizers

Answer

2. Establish a correspondence between the process taking place in the forest biocenosis and the environmental factor that it characterizes: 1) biotic, 2) abiotic
A) the relationship between aphids and ladybugs
B) waterlogging of the soil
C) daily change in illumination
D) competition between species of thrushes
D) increase in air humidity
E) the effect of the tinder fungus on the birch

Answer

3. Establish a correspondence between examples and environmental factors that are illustrated by these examples: 1) abiotic, 2) biotic. Write the numbers 1 and 2 in the correct order.
A) an increase in atmospheric air pressure
B) change in the topography of the ecosystem caused by an earthquake
C) a change in the population of hares as a result of an epidemic
D) interaction between wolves in a pack
D) competition for territory between pine trees in the forest

Answer

4. Establish a correspondence between the characteristics of the environmental factor and its type: 1) biotic, 2) abiotic. Write the numbers 1 and 2 in the correct order.
A) ultraviolet rays
B) drying up of water bodies during a drought
C) animal migration
D) pollination of plants by bees
D) photoperiodism
E) a decrease in the number of squirrels in lean years

Answer

6f. Establish a correspondence between examples and environmental factors that are illustrated by these examples: 1) abiotic, 2) biotic. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) an increase in soil acidity caused by a volcanic eruption
B) change in the relief of the biogeocenosis of the meadow after the flood
C) change in the population of wild boars as a result of the epidemic
D) interaction between aspens in the forest ecosystem
E) competition for territory between male tigers

Answer

7f. Establish a correspondence between environmental factors and groups of factors: 1) biotic, 2) abiotic. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) daily fluctuations in air temperature
B) change in the length of the day
B) predator-prey relationship
D) symbiosis of algae and fungus in lichen
D) change in the humidity of the environment

Answer

2. Match the examples with the environmental factors illustrated by these examples: 1) Biotic, 2) Abiotic, 3) Anthropogenic. Write the numbers 1, 2 and 3 in the correct order.
A) autumn leaves
B) Planting trees in the park
C) The formation of nitric acid in the soil during a thunderstorm
D) Illumination
E) The struggle for resources in the population
E) Freon emissions into the atmosphere

Answer

3. Establish a correspondence between examples and environmental factors: 1) abiotic, 2) biotic, 3) anthropogenic. Write down the numbers 1-3 in the order corresponding to the letters.
A) change in the gas composition of the atmosphere
B) dispersal of plant seeds by animals
C) human draining of swamps
D) an increase in the number of consumers in the biocenosis
D) change of seasons
E) deforestation

Answer

1. Choose three correct answers out of six and write them down in the numbers under which they are indicated. The following factors lead to a decrease in the number of squirrels in a coniferous forest:
1) reduction in the number of birds of prey and mammals
2) cutting down coniferous trees
3) harvest of spruce cones after a warm dry summer
4) increase in activity of predators
5) outbreak of epidemics
6) deep snow cover in winter

Answer

Choose three correct answers from six and write down the numbers under which they are indicated. The destruction of forests in vast areas leads to
1) an increase in the amount of harmful nitrogen impurities in the atmosphere
2) violation of the ozone layer
3) violation of the water regime
4) change of biogeocenoses
5) violation of the direction of air flows
6) reduction in species diversity

Answer

1. Choose three correct answers from six and write down the numbers under which they are indicated. Specify biotic factors among environmental factors.
1) flood
2) competition between individuals of the species
3) lowering the temperature
4) predation
5) lack of light
6) mycorrhiza formation

Answer

2. Choose three correct answers from six and write down the numbers under which they are indicated. The biotic factors are
1) predation
2) forest fire
3) competition between individuals of different species
4) rise in temperature
5) mycorrhiza formation
6) lack of moisture

Answer

1. Choose three correct answers out of six and write down the numbers under which they are indicated in the table. Which of the following environmental factors are abiotic?
1) air temperature
2) greenhouse gas pollution
3) the presence of non-recyclable garbage
4) the presence of a road
5) illumination
6) oxygen concentration

Answer

2. Choose three correct answers out of six and write down the numbers under which they are indicated in the table. Abiotic factors include:
1) Seasonal bird migration
2) Volcanic eruption
3) The appearance of a tornado
4) Construction by beavers of platinum
5) The formation of ozone during a thunderstorm
6) Deforestation

Answer

3. Choose three correct answers out of six and write down in the answer the numbers under which they are indicated. The abiotic components of the steppe ecosystem include:
1) herbaceous vegetation
2) wind erosion
3) the mineral composition of the soil
4) rainfall mode
5) species composition of microorganisms
6) seasonal livestock grazing

Answer

Choose three correct answers from six and write down the numbers under which they are indicated. What environmental factors may be limiting for brook trout?
1) fresh water
2) oxygen content less than 1.6 mg/l
3) water temperature +29 degrees
4) water salinity
5) illumination of the reservoir
6) the speed of the river

Answer

1. Establish a correspondence between the environmental factor and the group to which it belongs: 1) anthropogenic, 2) abiotic. Write the numbers 1 and 2 in the correct order.
A) artificial irrigation of land
B) meteorite fall
B) plowing virgin land
D) spring flood of waters
D) building a dam
E) movement of clouds

Answer

2. Establish a correspondence between the characteristics of the environment and the environmental factor: 1) anthropogenic, 2) abiotic. Write down the numbers 1 and 2 in the order corresponding to the letters.
A) deforestation
B) tropical showers
B) melting glaciers
D) forest plantations
D) draining swamps
E) an increase in the length of the day in spring

Answer

Choose three correct answers from six and write down the numbers under which they are indicated. The following anthropogenic factors can change the number of producers in an ecosystem:
1) collection of flowering plants
2) increase in the number of consumers of the first order
3) trampling of plants by tourists
4) decrease in soil moisture
5) cutting down hollow trees
6) increase in the number of consumers of the second and third orders

Answer

Read the text. Choose three sentences that describe abiotic factors. Write down the numbers under which they are indicated. (1) The main source of light on Earth is the Sun. (2) In photophilous plants, as a rule, strongly dissected leaf blades, a large number of stomata in the epidermis. (3) The humidity of the environment is an important condition for the existence of living organisms. (4) Plants evolved adaptations to maintain the body's water balance. (5) The content of carbon dioxide in the atmosphere is essential for living organisms.

Answer

Choose three correct answers from six and write down the numbers under which they are indicated. With a sharp decrease in the number of pollinating insects in the meadow over time
1) the number of insect pollinated plants is reduced
2) the number of birds of prey is increasing
3) the number of herbivores is increasing
4) the number of wind-pollinated plants increases
5) the water horizon of the soil changes
6) the number of insectivorous birds is decreasing

Answer