By “environment” we mean everything that surrounds the body and influences it in one way or another. In other words, the living environment is characterized by a certain set of environmental factors. Wednesday- living environment - aquatic environment - ground-air environment - soil environment - organism as a living environment - key concepts.
Generally accepted definition environment is the definition of Nikolai Pavlovich Naumov: " Wednesday- everything that surrounds organisms directly or indirectly affects their condition, development, survival and reproduction." On Earth there are four qualitatively different environments life that has a set of specific environmental factors: -ground-aquatic (land); - water; - soil; - other organisms.
Ground-air The environment is characterized by a huge variety of living conditions, ecological niches and the organisms inhabiting them. Organisms play a primary role in shaping the conditions of the land-air environment of life, and above all, the gas composition of the atmosphere. Almost all the oxygen earth's atmosphere is of biogenic origin. The main features of the ground-air environment are
Large changes in environmental factors,
Heterogeneity of the environment,
The action of the forces of gravity,
Low air density.
A complex of physical-geographical and climatic factors related to a certain natural area, leads to the adaptation of organisms to life in these conditions, the diversity of life forms. The high oxygen content in the atmosphere (about 21%) determines the possibility of forming a high (energy) level of metabolism. The atmospheric air is characterized by low and variable humidity. This circumstance largely limited the possibilities of developing the ground-air environment.
Atmosphere(from the Greek atmos - steam and sphaira - ball), the gaseous shell of the earth. It is impossible to indicate the exact upper limit of the earth's atmosphere. The atmosphere has a pronounced layered structure. Main layers of the atmosphere:
1)Troposphere- height 8 - 17 km. all water vapor and 4/5 of the mass of the atmosphere are concentrated in it and all weather phenomena develop.
2)Stratosphere- layer above the troposphere up to 40 km. It is characterized by almost complete constant temperature with altitude. In the upper part of the stratosphere there is a maximum concentration of ozone, which absorbs a large amount of ultraviolet radiation from the Sun.
3) Mesosphere- layer between 40 and 80 km; in its lower half the temperature rises from +20 to +30 degrees, in the upper half it drops to almost -100 degrees.
4) Thermosphere(ionosphere) - a layer between 80 - 1000 km, which has increased ionization of gas molecules (under the influence of unhindered penetrating cosmic radiation).
5) Exosphere(scattering sphere) - a layer above 800 - 1000 km, from which gas molecules are scattered into outer space. The atmosphere transmits 3/4 of solar radiation, thereby increasing the total amount of heat used for the development of natural processes on the Earth.
Aquatic life environment. Hydrosphere (from hydro... and sphere), the intermittent water shell of the Earth, located between the atmosphere and the solid earth's crust(lithosphere). Represents the collection of oceans, seas, lakes, rivers, swamps, as well as groundwater. The hydrosphere covers about 71% of the earth's surface. Chemical composition The hydrosphere approaches the average composition of sea water.
The amount of fresh water makes up 2.5% of all water on the planet; 85% - sea water. Fresh water reserves are distributed extremely unevenly: 72.2% - ice; 22.4% - groundwater; 0.35% - atmosphere; 5.05% - stable river flow and lake water. The water we can use accounts for only 10-12% of all fresh water on Earth.
Primary environment life was precisely the aquatic environment. First of all, most organisms are not capable of active life without water entering the body or without maintaining a certain fluid content inside the body. Main feature aquatic environment, is: daily and seasonal temperature fluctuations. Huge ecological significance, have a high density and viscosity of water. The specific gravity of water is comparable to that of the body of living organisms. The density of water is approximately 1000 times higher than the density of air. Therefore, aquatic organisms (especially actively moving ones) encounter a greater force of hydrodynamic resistance. The high density of water is the reason why mechanical vibrations(vibrations) propagate well in the aquatic environment. This is very important for the senses, orientation in space and between aquatic inhabitants. The speed of sound in the aquatic environment has a higher frequency of echolocation signals. Four times larger than in the air. Therefore, there is a whole group of aquatic organisms (both plants and animals) that exist without a mandatory connection with the bottom or other substrate, “floating” in the water column.
What animals live in the air? What animals can fly besides birds? If you are looking for an answer to this question, then after reading this article you will find the answer.
Animals living in the air
They spend a significant part of their lives in the air birds, butterflies, flies and other animals. Wings help them fly. Among the animals only bats have wings and are capable of active flight. Other representatives of animals can only stay in the air for a while when they jump from tree to tree. For example, in flying squirrels On the sides of the body there are wide folds of skin, which she straightens in the air and uses as a parachute.
Among modern inhabitants of the land-air environment capable of flight, there are no animals with a large mass. A significant mass would prevent the animal from lifting its body into the air.
Animals that live in the air:
Birds- a special group of animals capable of flight and movement on land and water. They easily rise up, deftly overcome air currents, and some also hunt in the air. It's not just their wings that help birds fly into the air and move around. Flight is facilitated by feathers and air, which is in the cavities of the bird's bones, which makes the bird lighter.
Flying lemurs. These animals are found in the Philippines, Indonesia, Malaysia and southern China. The animal is helped to fly by a more advanced membrane than in squirrels, connecting the neck, fingertips and tail. Although much larger than other flying animals, this animal is still no larger than a cat. Females have gray fur, while males have chocolate fur. They feed on fruits, leaves, and seeds. They eat, like other flying mammals, at night, and during the day they sleep, hanging somewhere on a branch upside down. The female woolwing gives birth to only one young. During the flight, the baby hangs on the mother's chest, tightly clinging to the fur. Woolly wings are capable of covering distances of up to 136 m in the air.
Flying squirrels. Most flying squirrels are very small in size, reaching no more than 135 mm in length (plus, like all squirrels, a long, bushy tail). Flying squirrels usually settle in forests, making homes in tree hollows hollowed out by woodpeckers or in natural tree hollows. Their main diet consists of bark, buds, leaves and seeds, and on the ground they readily feast on mushrooms and berries. While not strict vegetarians, some species of flying squirrels can feed on bird eggs, insects and other small animals. Unlike an ordinary squirrel, it is quite difficult to see a flying squirrel in the forest, since it only comes out to feed at night. Before the flight begins, the flying squirrel climbs to the top of a tree, pushes off sharply and, straightening the leathery membranes between its legs, smoothly soars in the air.
Flying possums. Opossums are marsupials that live in Australia and New Zealand. They resemble a flying squirrel not only in their membrane, but also in their long fluffy tail.
There are 3 groups of flying possums: the first is the smallest meat-eating possums, or sugar possums. Their weight reaches no more than 130 grams, their characteristic features are a gray back and a white chest.
We hope the information in the article “animals that live in the air” was useful for you, and you found something new and interesting for yourself.
Characteristics of the ground-air habitat!!!
In the ground-air environment, the operating environmental factors have a number of characteristic features: higher light intensity compared to other environments, significant temperature fluctuations, changes in humidity depending on geographical location, season and time of day
In the course of evolution, this environment was developed later than the aquatic environment. Its peculiarity is that it is gaseous, therefore it is characterized by low humidity, density and pressure, and high oxygen content. In the course of evolution, living organisms have developed the necessary anatomical, morphological, physiological, behavioral and other adaptations.
Animals in the ground-air environment move on the soil or through the air (birds, insects), and plants take root in the soil. In this regard, animals have lungs and trachea, and plants have a stomatal apparatus, i.e., organs with which the land inhabitants of the planet absorb oxygen directly from the air. Skeletal organs have developed strongly, ensuring autonomy of movement on land and supporting the body with all its organs in conditions of low density of the environment, thousands of times less than water. Ecological factors in the ground-air environment differ from other habitats in the high intensity of light, significant fluctuations in temperature and air humidity, and the correlation of all factors with geographical location, changing seasons of the year and time of day. Their effects on organisms are inextricably linked with air movement and position relative to the seas and oceans and are very different from the effects in the aquatic environment (Table 1).
Table 5
Habitat conditions for air and water organisms
(according to D.F. Mordukhai-Boltovsky, 1974)
Habitat conditions (factors)The importance of conditions for organisms
air environmentaquatic environment
HumidityVery important (often in short supply) Not present (always in excess)
DensityInsignificant (except for soil) Large compared to its role for the inhabitants of the air
Pressure is almost non-existent (can reach 1000 atmospheres)
TemperatureSignificant (varies within very wide limits from -80 to +1OOC or more) Less than the value for the inhabitants of the air (varies much less, usually from -2 to +40C)
Oxygen Non-essential (mostly in excess) Essential (often in deficiency)
Suspended solidsUnimportant; not used for food (mainly minerals) Important (food source, especially organic matter)
Dissolved substances in the environmentTo some extent (only relevant in soil solutions) Important (required in certain quantities)
Land animals and plants have developed their own, no less original adaptations to unfavorable environmental factors: the complex structure of the body and its integument, the periodicity and rhythm of life cycles, thermoregulation mechanisms, etc. Targeted mobility of animals in search of food has developed, wind-borne spores, seeds and pollen, as well as plants and animals whose life is entirely connected with the air. An exceptionally close functional, resource and mechanical relationship with the soil has been formed.
Many of the adaptations were discussed above, as examples in characterizing abiotic factors environment. Therefore, there is no point in repeating myself now, b. that we will return to them in practical classes
Life on land largely depends on the state of the air. The natural mixture of gases that developed during the evolution of the Earth is the air we breathe.
Air as a medium of life guides evolutionary development inhabitants of this environment. Thus, a high oxygen content determines the possibility of forming a high level of energy metabolism (metabolism between the body and the environment). Atmospheric air is characterized by low and variable humidity, which limited the possibilities of developing the air environment, and among its inhabitants determined the evolution of the water-salt metabolism system and the structure of the respiratory organs. It should also be noted that the air density in the atmosphere is low, due to which life is concentrated near the surface of the Earth and penetrates into the atmosphere to a height of no more than 50-70 m (tree crowns of tropical forests).
The main components of atmospheric air are nitrogen (N2) - 78.08%, oxygen (02) - 20.9%, argon (Ar) - about 1% and carbon dioxide (CO2) - 0.03% (Table 1).
Oxygen appeared on Earth approximately 2 billion years ago, when the surface was formed under the influence of active volcanic activity. Over the past 20 million years, the proportion of oxygen in the air has gradually increased (today it is 21%). Main role development played a role in this flora land and ocean.
Table 1. Gas composition of the Earth's atmosphere
The atmosphere protects the Earth from meteorite bombardment. About 5 times a year, fragments of meteorites, comets and asteroids burn up in the atmosphere, the power of which, upon meeting the Earth, would exceed the power of the bomb dropped on Hiroshima. Most meteorites never reach the earth's surface; they burn up when they enter the atmosphere at high speed. About 6 million tons of cosmic dust fall on Earth every year.
In addition, the atmosphere helps to retain heat on the planet, which would otherwise be dissipated in the cold outer space. The atmosphere itself does not evaporate due to the force of gravity.
At an altitude of 20-25 km from the surface of the Earth there is a protective layer that blocks ultraviolet radiation, which is destructive for all living things. Without it, such radiation could destroy life on Earth. Unfortunately, starting from the 80-90s. XX century There is a negative trend towards thinning and destruction of the ozone screen.
Layered structure of the Earth's shells and the composition of the atmosphere; light regime as a factor of the ground-air environment; adaptation of organisms to different light regimes; temperature regime in the ground-air environment, temperature adaptations; air pollution
The ground-air environment is the most complex in terms of ecological living conditions. Life on land required such morphological and biochemical adaptations that were possible only with a sufficiently high level of organization of both plants and animals. In Fig. Figure 2 shows a diagram of the Earth's shells. The ground-air environment includes the outer part lithosphere and lower part atmosphere. The atmosphere, in turn, has a fairly clearly defined layered structure. The lower layers of the atmosphere are shown in Fig. 2. Since the bulk of living beings live in the troposphere, it is this layer of the atmosphere that is included in the concept of the ground-air environment. The troposphere is the lowest part of the atmosphere. Its height in different areas is from 7 to 18 km, it contains the bulk of water vapor, which, when condensed, form clouds. In the troposphere there is a powerful movement of air, and the temperature drops by an average of 0.6 ° C with a rise for every 100 m.
The Earth's atmosphere consists of a mechanical mixture of gases that do not chemically affect each other. All meteorological processes take place in it, the totality of which is called climate. The upper boundary of the atmosphere is conventionally considered to be 2000 km, i.e. its height is 3 times the radius of the Earth. Various physical processes continuously occur in the atmosphere: temperature and humidity change, water vapor condenses, fogs and clouds appear, the sun's rays heat the atmosphere, ionizing it, etc.
The bulk of the air is concentrated in the 70 km layer. Dry air contains (in%): nitrogen - 78.08; oxygen - 20.95; argon - 0.93; carbon dioxide - 0.03. There are very few other gases. These are hydrogen, neon, helium, krypton, radon, xenon - most of the inert gases.
Atmospheric air is one of the main vital elements environment. It reliably protects the planet from harmful cosmic radiation. Under the influence of the atmosphere on Earth, the most important geological processes, which ultimately shape the landscape.
Atmospheric air belongs to the category of inexhaustible resources, but intensive industrial development, urban growth, and expansion of space research increase the negative anthropogenic impact on the atmosphere. Therefore, the issue of protecting atmospheric air is becoming increasingly relevant.
In addition to air of a certain composition, living organisms inhabiting the ground-air environment are affected by air pressure and humidity, as well as solar radiation and temperature.
Rice. 2.
Light regime, or solar radiation. To carry out life processes, all living organisms need energy coming from outside. Its main source is solar radiation.
The effect of different parts of the solar radiation spectrum on living organisms is different. It is known that in the spectrum of solar rays there are ultraviolet, visible And infrared region, which, in turn, consist of light waves of different lengths (Fig. 3).
Among ultraviolet rays (UVR), only long-wave rays (290-300 nm) reach the Earth's surface, and short-wave rays (less than 290 nm), destructive for all living things, are almost completely absorbed at an altitude of about 20-25 km by the ozone screen - a thin layer of the atmosphere containing molecules 0 3 (see Fig. 2).
Rice. 3. Biological effect of different parts of the solar radiation spectrum: 1 - protein denaturation; 2 - intensity of wheat photosynthesis; 3 - spectral sensitivity of the human eye. The area of ultraviolet radiation that does not penetrate is shaded
through the atmosphere
Long-wave ultraviolet rays (300-400 nm), which have high photon energy, have high chemical and mutagenic activity. Large doses are harmful to organisms.
In the range of 250-300 nm, UV rays have a powerful bactericidal effect and cause the formation of anti-rickets vitamin D in animals, i.e., small doses of UV rays are necessary for humans and animals. At a length of 300-400 nm, UV rays cause a tan in humans, which is a protective reaction of the skin.
Infrared rays (IRL) with a wavelength of more than 750 nm have a thermal effect, are not perceived by the human eye and provide the thermal regime of the planet. These rays are especially important for cold-blooded animals (insects, reptiles), which use them to increase their body temperature (butterflies, lizards, snakes) or for hunting (ticks, spiders, snakes).
Currently, many devices have been manufactured that use one or another part of the spectrum: ultraviolet irradiators, household appliances with infrared radiation for quick cooking, etc.
Visible rays with a wavelength of 400-750 nm have great value for all living organisms.
Light as a condition for plant life. Light is absolutely necessary for plants. Green plants use solar energy in this particular region of the spectrum, capturing it during photosynthesis:
Due to the different needs for light energy in plants, different morphological and physiological adaptations to the light regime of habitation.
Adaptation is a system for regulating metabolic processes and physiological characteristics that ensure maximum adaptability of organisms to environmental conditions.
In accordance with adaptations to light conditions, plants are divided into the following ecological groups.
- 1. Photophilous- having the following morphological adaptations: highly branching shoots with shortened internodes, rosette-shaped; the leaves are small or with a strongly dissected leaf blade, often with a waxy coating or pubescence, often with the edge turned towards the light (for example, acacia, mimosa, sophora, cornflower, feather grass, pine, tulip).
- 2. Shade-loving- constantly located in conditions of strong shading. Their leaves are dark green and arranged horizontally. These are plants of the lower tiers of forests (for example, wintergreens, bifolia, ferns, etc.). When there is a lack of light, deep-sea plants (red and brown algae) live.
- 3. Shade-tolerant- can tolerate shading, but also grow well in the light (for example, forest herbs and shrubs that grow in shaded areas and on the edges, as well as oak, beech, hornbeam, spruce).
In relation to the light, plants in the forest are arranged in tiers. In addition, even on the same tree, leaves capture light differently depending on the tier. As a rule, they are sheet mosaic, that is, they are positioned in such a way as to increase the leaf surface for better light capture.
The light regime varies depending on the geographic latitude, time of day and time of year. Due to the rotation of the Earth, the light regime has a distinct daily and seasonal rhythm. The body's reaction to a change in lighting conditions is called photoperiodism. Due to photoperiodism, the processes of metabolism, growth and development in the body change.
The phenomenon associated with photoperiodism in plants phototropism- movement of individual plant organs towards light. For example, the movement of a sunflower basket during the day following the sun, the opening of dandelion and bindweed inflorescences in the morning and closing them in the evening, and vice versa - the opening of night violet and fragrant tobacco flowers in the evening and closing them in the morning (daily photoperiodism).
Seasonal photoperiodism is observed in latitudes with changing seasons (temperate and northern latitudes). With the onset of a long day (spring), active sap flow is observed in the plants, the buds swell and open. When the short autumn days arrive, plants shed their leaves and prepare for winter dormancy. It is necessary to distinguish between “short-day” plants - they are common in the subtropics (chrysanthemums, perilla, rice, soybean, cocklebur, hemp); and “long-day” plants (rudbeckia, cereals, cruciferous vegetables, dill) - they are distributed mainly in temperate and subpolar latitudes. Long-day plants cannot grow in the south (they do not produce seeds), and the same applies to short-day plants if grown in the north.
Light as a condition for animal life. For animals, light is not a factor of primary importance, as it is for green plants, since they exist due to the energy of the sun accumulated by these plants. However, animals need a certain amount of light spectral composition. They mainly need light for visual orientation in space. True, not all animals have eyes. In primitive people, these are simply photosensitive cells or even a place in the cell (for example, stigma in single-celled organisms or "photosensitive eye").
Figurative vision is possible only with a sufficiently complex structure of the eye. For example, spiders can distinguish the contours of moving objects only at a distance of 1-2 cm. The eyes of vertebrates perceive the shape and size of objects, their color and determine the distance to them.
Visible light is a conventional concept for different species of animals. For humans, these are rays from violet to dark red (remember the colors of the rainbow). Rattlesnakes, for example, perceive the infrared part of the spectrum. Bees distinguish the multicolored ultraviolet rays, but do not perceive red ones. The spectrum of visible light for them is shifted to the ultraviolet region.
The development of the visual organs largely depends on the environmental situation and living conditions of organisms. Thus, in permanent inhabitants of caves where sunlight does not penetrate, the eyes can be completely or partially reduced: in blind ground beetles, bats, some amphibians and fish.
The ability for color vision also depends on whether the organisms are diurnal or nocturnal. Canines, cats, and hamsters (which feed by hunting at dusk) see everything in black and white. Nocturnal birds - owls and nightjars - have the same vision. Diurnal birds have well-developed color vision.
Animals and birds also have adaptations to diurnal and nocturnal lifestyles. For example, most ungulates, bears, wolves, eagles, larks, are active during the day, while tigers, mice, hedgehogs, and owls are most active at night. The length of daylight hours affects the onset of mating season, migrations and migrations in birds, hibernation in mammals, etc.
Animals navigate with the help of their visual organs during long flights and migrations. Birds, for example, choose their flight direction with amazing accuracy, covering many thousands of kilometers from nesting sites to wintering grounds. It has been proven that during such long flights, birds are at least partially oriented by the Sun and stars, i.e., astronomical light sources. They are capable of navigation, changing orientation to get into desired point Earth. If birds are transported in cages, then they correctly choose the direction for wintering from anywhere on Earth. Birds do not fly in continuous fog, as during the flight they often lose their way.
Among insects, the ability for this kind of orientation is developed in bees. They use the position (height) of the Sun as a guide.
Temperature regime in the ground-air environment. Temperature adaptations. It is known that life is a way of existence of protein bodies, therefore the boundaries of the existence of life are the temperatures at which the normal structure and functioning of proteins is possible, on average from 0°C to +50°C. However, some organisms have specialized enzyme systems and are adapted to active existence at temperatures beyond these limits.
Species that prefer cold (they are called cryophiles), can maintain cell activity down to -8°... -10°C. Bacteria, fungi, lichens, mosses, and arthropods can tolerate hypothermia. Our trees also do not die in low temperatures. It is only important that during the period of preparation for winter, the water in the plant cells passes into a special state, and does not turn into ice - then the cells die. Plants overcome hypothermia by accumulating substances in their cells and tissues - osmotic protectors: various sugars, amino acids, alcohols, which “pump out” excess water, preventing it from turning into ice.
There is a group of species of organisms whose optimum life is high temperatures, they are called thermophiles. These are various worms, insects, mites that live in deserts and hot semi-deserts, these are bacteria from hot springs. There are springs with a temperature of + 70°C containing living inhabitants - blue-green algae (cyanobacteria), some types of mollusks.
If we take into account latent(long-term dormant) forms of organisms, such as spores of some bacteria, cysts, spores and plant seeds, then they can withstand significantly different temperatures. Bacterial spores can withstand heat up to 180°C. Many seeds, plant pollen, cysts, unicellular algae can withstand freezing in liquid nitrogen (at -195.8°C), and then long-term storage at -70°C. After defrosting and placing in favorable conditions and a sufficient nutrient medium, these cells can become active again and begin to multiply.
Temporary suspension of all vital processes of the body is called suspended animation. Anabiosis can occur in animals both when the ambient temperature decreases and when it increases. For example, in snakes and lizards, when the air temperature rises above 45°C, thermal torpor occurs. Amphibians have virtually no vital activity at water temperatures below 4°C. From a state of suspended animation, living beings can return to normal life only if the structure of macromolecules in their cells (primarily DNA and proteins) is not disturbed.
Resistance to temperature fluctuations varies among terrestrial inhabitants.
Temperature adaptations in plants. Plants, being immobile organisms, are forced to adapt to the temperature fluctuations that exist in their habitats. They have specific systems that protect against hypothermia or overheating. Transpiration- this is a system for evaporating water by plants through the stomatal apparatus, which saves them from overheating. Some plants have even become resistant to fires - they are called pyrophytes. Fires often occur in savannas and bushland. Savannah trees have thick bark impregnated with fire-resistant substances. The fruits and their seeds have thick, woody coverings that crack when engulfed in fire, which helps the seeds penetrate the ground.
Temperature adaptations of animals. Animals, compared to plants, have greater ability to adapt to temperature changes, since they are able to move, have muscles and produce their own internal heat. Depending on the mechanisms for maintaining a constant body temperature, there are poikilothermic(cold-blooded) and homeothermic(warm-blooded) animals.
Poikilothermic- These are insects, fish, amphibians, and reptiles. Their body temperature changes along with the ambient temperature.
Homeothermic- animals with a constant body temperature, capable of maintaining it even with strong fluctuations in external temperature (these are mammals and birds).
The main ways of temperature adaptation:
- 1) chemical thermoregulation- increase in heat production in response to a decrease in ambient temperature;
- 2) physical thermoregulation- the ability to retain heat due to hair and feathers, the distribution of fat reserves, the possibility of evaporative heat transfer, etc.;
3) behavioral thermoregulation- the ability to move from places of extreme temperatures to places of optimal temperatures. This is the main way of thermoregulation in poikilothermic animals. When the temperature rises or falls, they tend to change their position or hide in the shadows, in a hole. Bees, ants, and termites build nests with well-regulated temperatures inside them.
In warm-blooded animals, the thermoregulation system has been significantly improved (although it is weak in cubs and chicks).
To illustrate the perfection of thermoregulation in higher animals and humans, the following example can be given. About 200 years ago, Dr. C. Blagden in England performed the following experiment: he, along with friends and a dog, spent 45 minutes in a dry chamber at +126°C without any health consequences. Fans of the Finnish sauna know that you can spend some time in a sauna with a temperature of more than + 100°C (for each person), and this is good for health. But we also know that if you hold a piece of meat at this temperature, it will cook.
When exposed to cold, warm-blooded animals intensify oxidative processes, especially in the muscles. Chemical thermoregulation comes into play. Muscle tremors are noted, leading to the release of additional heat. Lipid metabolism is especially enhanced, since fats contain a significant supply of chemical energy. Therefore, the accumulation of fat reserves provides better thermoregulation.
Increased heat production is accompanied by the consumption of large amounts of food. So, birds staying for the winter need a lot of food; they are afraid not of frost, but of lack of food. When the harvest is good, spruce and pine crossbills, for example, hatch chicks even in winter. People - residents of harsh Siberian or northern regions - have developed a high-calorie menu from generation to generation - traditional dumplings and other high-calorie foods. Therefore, before following fashionable Western diets and rejecting the food of our ancestors, we need to remember the expediency existing in nature, which underlies the long-term traditions of people.
An effective mechanism for regulating heat exchange in animals, as in plants, is the evaporation of water through sweating or through the mucous membranes of the mouth and upper respiratory tract. This is an example of physical thermoregulation. A person in extreme heat can produce up to 12 liters of sweat per day, dissipating 10 times more heat than normal. The excreted water must be partially returned through drinking.
Warm-blooded animals, like cold-blooded animals, are characterized by behavioral thermoregulation. In the burrows of animals living underground, temperature fluctuations are smaller, the deeper the burrow. In skillfully constructed bee nests an even, favorable microclimate is maintained. Of particular interest is the group behavior of animals. For example, in severe frost and snowstorms, penguins form a “turtle” - a dense heap. Those who find themselves on the edge gradually make their way inside, where the temperature is maintained at about +37°C. There, inside, the cubs are also placed.
Thus, in order to live and reproduce in certain conditions of the land-air environment, animals and plants in the process of evolution have developed a wide variety of adaptations and systems to suit this habitat.
Ground-air pollution. Recently, an increasingly significant external factor changing the ground-air habitat has become anthropogenic factor.
The atmosphere, like the biosphere, has the property of self-purification, or maintaining balance. However, the volume and speed of modern atmospheric pollution exceed the natural capabilities of their neutralization.
Firstly, this is natural pollution - various dusts: mineral (products of weathering and destruction of rocks), organic (aeroplankton - bacteria, viruses, pollen) and cosmic (particles entering the atmosphere from space).
Secondly, it is artificial (anthropogenic) pollution - industrial, transport and household emissions into the atmosphere (dust from cement factories, soot, various gases, radioactive pollution, pesticides).
According to rough estimates, 1.5 million tons of arsenic have been released into the atmosphere over the past 100 years; 1 million tons of nickel; 1.35 million tons of silicon, 900 thousand tons of cobalt, 600 thousand tons of zinc, the same amount of copper and other metals.
Chemical plants emit carbon dioxide, iron oxide, nitrogen oxides, and chlorine. Of the pesticides, organophosphorus compounds are especially toxic, from which they become even more toxic in the atmosphere.
As a result of emissions in cities where ultraviolet radiation is reduced and there are large crowds of people, air degradation occurs, one of the manifestations of which is smog.
Smog happens "classical"(a mixture of toxic fogs that occur when there is little cloud) and " photochemical"(a mixture of corrosive gases and aerosols that is formed without fog as a result of photochemical reactions). London and Los Angeles smog are the most dangerous. It absorbs up to 25% of solar radiation and 80% of ultraviolet rays, and the urban population suffers from this.
The ground-air environment is the most difficult for the life of organisms. The physical factors that make it up are very diverse: light, temperature. But organisms have adapted during evolution to these changing factors and have developed adaptation systems to ensure extreme adaptability to living conditions. Despite the inexhaustibility of air as an environmental resource, its quality is rapidly deteriorating. Air pollution is the most dangerous form of environmental pollution.
Questions and tasks for self-control
- 1. Explain why the ground-air environment is the most difficult for the life of organisms.
- 2. Give examples of adaptations in plants and animals to high and low temperatures.
- 3. Why does temperature have a strong influence on the life activity of any organisms?
- 4. Analyze how light affects the life of plants and animals.
- 5. Describe what photoperiodism is.
- 6. Prove that different waves of the light spectrum have different effects on living organisms, give examples. List what groups living organisms are divided into according to the way they use energy, give examples.
- 7. Comment on what causes seasonal phenomena in nature and how plants and animals react to them.
- 8. Explain why land-air pollution poses the greatest danger to living organisms.
