Abiotic factors. Temperature
Abiotic factors- all components and phenomena of inanimate nature.
Temperature refers to climatic abiotic environmental factors. Most organisms are adapted to a rather narrow temperature range, since the activity of cellular enzymes ranges from 10 to 40 ° C; at low temperatures, reactions proceed slowly.
Animal organisms are distinguished:
- with a constant body temperature ( warm-blooded, or homeothermic);
- with unstable body temperature ( cold-blooded, or poikilothermic).
Plants and animals have special adaptationscooling, allowing adaptation to temperature fluctuations.
Organisms whose body temperature changes depending on the temperature of the environment (plants, invertebrate animals, fish, amphibians and reptiles) have various adaptations to maintain life. Such animals are called cold-blooded, or poikilothermic. The lack of a thermoregulation mechanism is due to poor development of the nervous system, low metabolic rate and the absence of a closed circulatory system.
The body temperature of poikilothermic animals is only 1-2 °C higher than the ambient temperature or equal to it, but it can increase as a result of absorption of solar heat (snakes, lizards) or muscular work (flying insects, fast-swimming fish). Sudden fluctuations in environmental temperature can lead to death.
With the onset of winter, plants and animals enter a state of winter dormancy. Their metabolic rate drops sharply. In preparation for winter, a lot of fat and carbohydrates are stored in animal tissues, the amount of water in fiber decreases, sugars and glycerin accumulate, which prevents freezing.
Species with an unstable body temperature are able to go into an inactive state when the temperature drops. Slowing down metabolism in cells greatly increases the resistance of organisms to adverse weather conditions. The transition of animals into a state of torpor, like the transition of plants into a state of rest, allows them to endure the winter cold with minimal losses, without spending a lot of energy.
To protect organisms from overheating in the hot season, special physiological mechanisms are activated: in plants, the evaporation of moisture through the stomata increases; in animals, the evaporation of water through the respiratory system and skin increases.
In poikilothermic organisms, internal body temperature follows changes in environmental temperature. Their metabolic rate either increases or decreases. Such species are the majority on Earth.
Organisms with a constant body temperature are called warm-blooded, or homeothermic. These include birds and mammals.
The body temperature of such animals is stable, it does not depend on the temperature of the environment, due to the presence of thermoregulation mechanisms. The constancy of body temperature is ensured by the regulation of heat production and heat transfer.
When there is a threat of overheating of the body, skin vessels dilate, sweating and heat transfer increase. When there is a threat of cooling, the skin vessels narrow, the fur or feathers rise - heat transfer is limited.
With significant changes in external temperature and sudden changes in heat production, the temperature of internal organs in warm-blooded animals may deviate from normal values from 0.2-0.3 to 1-3 °C.
Sweating is characteristic only of humans, monkeys and equids. In other homeothermic animals, the most effective mechanism for heat loss is thermal panting. The ability to increase heat production is most pronounced in birds, rodents and some other animals.
Homeotherms are able to maintain a constant body temperature under any environmental conditions. Their metabolism always runs at a high speed, even if the outside temperature is constantly changing. For example, polar bears in the Arctic or penguins in Antarctica can withstand frosts of 50 degrees, which is a difference of 87-90 degrees compared to their own temperature.
Adaptations of organisms to different temperature conditions. Both warm-blooded and cold-blooded animals, in the process of evolution, have developed various adaptations to changing temperature conditions of the environment.The main source of thermal energy in organisms with unstable body temperature is external heat.
It takes two to three weeks for overwintered snakes to bring their metabolism to a sufficient intensity. Typically, snakes crawl out and bask in the sun repeatedly throughout the day, and return to their burrows at night.
With the onset of winter, plants and animals with unstable body temperatures enter a state of winter dormancy. Their metabolic rate decreases sharply. In preparation for winter, a lot of fats and carbohydrates are stored in the tissues.
In autumn, plants reduce their consumption of substances by storing sugar and starch. Their growth stops, the intensity of all physiological processes slows down sharply, and the leaves fall off. During the first frosts, plants lose a significant amount of water, becoming frost-resistant and entering a state of deep dormancy.
During the hot season, overheating protection mechanisms are activated. In plants, water evaporation increases through the stomata, and in animals - through the respiratory system and skin.
If the plants are sufficiently supplied with water, the stomata are open day and night. However, in many plants the stomata are open only during the day in the light and close at night. In dry, hot weather, plant stomata close even during the day, and the release of water vapor from the leaves into the air stops. When favorable conditions occur, the stomata open and normal plant activity is restored.
The most perfect thermoregulation is observed in animals with a constant body temperature. Regulation of heat transfer by skin vessels and well-developed higher nervous activity allowed birds and mammals to remain active during sudden temperature changes and to master almost all habitats.
Complete division of blood into venous and arterial, intensive metabolism, feathers or body hair that help retain heat.
Of great importance for warm-blooded animals is not only the ability to thermoregulate, but also adaptive behavior, the construction of special shelters and nests.
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 classified as “individual”, and substrate, climate, microclimate, etc. - as “complex” factors.
The substrate (literally) is the site of attachment. For example, for woody and herbaceous forms of plants, for soil microorganisms this is soil. In some cases, substrate can be considered synonymous with 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 represents a complex of characteristic biotic and abiotic factors to which this or that organism adapts.
Characteristics of temperature as an abiotic environmental factor
Temperature is an environmental factor associated with the average kinetic energy of particle motion and expressed in degrees on various scales. The most common scale is in degrees Celsius (°C), which is based on the expansion of water (the boiling point of water is 100°C). The SI adopts an absolute temperature scale, for which the boiling point of water is T bp. water = 373 K.
Very often, temperature is the limiting factor that determines the possibility (impossibility) of living of organisms in a particular habitat.
According to the nature of body temperature, 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 homeothermic (their body temperature does not depend on the external temperature and is more or less constant: if it fluctuates, it is within small limits - fractions of a degree).
Poikilothermic organisms 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, making it possible to settle into a larger number of ecological niches, both in latitudinal and vertical distribution across the planet. However, in addition to homeothermy, organisms develop adaptations to overcome the effects of low temperatures.
Based on the nature of their tolerance to low temperatures, plants are divided into heat-loving and cold-resistant. 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 specific 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 limits of temperature influence at which life is preserved are very wide. Thus, in California, in hot springs there lives a species of fish that normally functions at a temperature of 52 ° C, and heat-resistant bacteria living in geysers can withstand temperatures up to 80 ° C (this is the “normal” temperature for them). Some people live in glaciers at a temperature of -44°C, 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 death.
The influence of temperature on plant organisms
Temperature is not only a factor determining the possibility of plants living in a particular area, but for some plants it affects the process of their development. Thus, winter varieties of wheat and rye, which during germination did not undergo the process of “vernalization” (exposure to low temperatures), do not produce seeds when grown in the most favorable conditions.
To withstand the effects of low temperatures, plants have various adaptations.
1. In winter, the cytoplasm loses water and accumulates substances that have an “antifreeze” effect (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, roots, 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 temperatures that are optimal for their life. During periods of low temperatures, they hibernate (amphibians, reptiles, arthropods, etc.). Some insects overwinter either as eggs or as pupae. The presence of an organism in hibernation is characterized by a state of suspended animation, in which metabolic processes are very inhibited and the body can go without food for a long time. Poikilothermic animals can also hibernate when exposed to high temperatures. Thus, animals in lower latitudes are in burrows during the hottest part of the day, and the period of their active life activity occurs in the early morning or late evening (or they are nocturnal).
Animal organisms hibernate not only due to the influence of temperature, but also due to other factors. Thus, a bear (a homeothermic animal) hibernates in winter due to lack of food.
Homeothermic animals are less dependent on temperature in their life activities, but temperature affects them from the point of view of the availability (absence) of food supply. These animals have the following adaptations to overcome the effects of low temperatures:
1) animals move from colder areas to warmer ones (bird migrations, mammal migrations);
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 the effects of temperatures (both high and low). Thus, 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, various radiations play a huge role, which either enter the planet from the outside (sun rays) or are released from the bowels of the Earth. Here we will mainly consider solar radiation.
Solar radiation is heterogeneous and consists of electromagnetic waves of different lengths, and therefore have different energies. Rays of both the visible and invisible spectrum reach the Earth's surface. Rays of the invisible spectrum include infrared and ultraviolet rays, and rays of the visible spectrum have seven 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 environmentally important functions:
1) thanks to the sun's rays, a certain temperature regime is realized on the surface of the Earth, which has a latitudinal and vertical zonal character;
In the absence of human influence, the composition of the air may, however, vary depending on the altitude (with altitude, 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 in the impurities of compounds released by various plants (for example, the air of a pine forest contains a large amount of resinous substances and esters that kill pathogens, so this air is healing for patients with tuberculosis).
The most important complex abiotic factor is climate.
Climate is a cumulative abiotic factor, including a certain composition and level of solar radiation, the associated level of temperature and humidity influence and a certain wind regime. The climate also depends on the nature of the vegetation growing in a given area and on the terrain.
There is a certain latitudinal and vertical climatic zonation on Earth. There are humid tropical, subtropical, sharply continental and other types of climate.
Review the information about different types of climate from the physical geography textbook. Consider the climate characteristics of the area where you live.
Climate as a cumulative factor shapes 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 in which you live and the temperature regime of the area where the city is located.
As a rule, the temperature within 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 microclimate is differences in the relief in a given territory, the presence of reservoirs, which leads to changes in conditions in different territories of a given climatic zone. Even in a relatively small area of a summer cottage, in certain parts of it, different conditions for plant growth may arise due to different lighting conditions.
Signal for the beginning of the autumn migration of insectivorous birds
1) lowering the ambient temperature 2) reducing daylight hours
3) lack of food 4) increased humidity and pressure
Does NOT affect the number of squirrels in the forest zone
Abiotic factors include
1) competition between plants for light absorption
2) the influence of plants on animal life
3) temperature change during the day
4) human pollution
Factor limiting the growth of herbaceous plants in a spruce forest - disadvantage
1) light 2) heat 3) water 4) minerals
What is a factor that deviates significantly from the optimal value for a species called?
1) abiotic 2) biotic 3) anthropogenic 4) limiting
44. What factor limits plant life in the steppe zone?
1) high temperature 2) lack of moisture 3) lack of humus
4) excess ultraviolet rays
The most important abiotic factor mineralizing organic residues in the forest biogeocenosis is
1) frosts 2) fires 3) winds 4) rains
Abiotic factors that determine population size include
The main limiting factor for plant life in the Indian Ocean is the lack of
1) light 2) heat 3) mineral salts 4) organic substances
48. What can become a limiting factor for the life of the sika deer living in Primorye on the southern slopes of the mountains?
1) deep snow 2) strong wind 3) lack of coniferous trees
4) short day in winter
Abiotic environmental factors include
1) soil fertility 2) wide variety of plants
3) presence of predators 4) air temperature
41. Any environmental factor can be limiting, but the most important are often:
1) humidity and food
2) temperature, for plants - the presence of mineral nutrition elements
3) temperature, water, food, for plants - the presence of nutrients in the soil
42. Organisms with a wide range of tolerance - endurance ~ are called:
1) stenobionts, they are practically not found in nature
2) eurybionts, they are widespread in nature
3) eurybionts, they are rarely found in nature
43. The size of the leaves is the same under conditions in which:
1) dark - humid and dry - sunny
2) dark - humid and humid - sunny
3) dry - sunny and sunny - humid
44. An ecologist-hydrobiologist always has a device ready to determine the amount of oxygen, and an ecologist studying terrestrial ecosystems measures the oxygen content less often because:
1) In terrestrial habitats, oxygen is available to living beings, in aquatic habitats it is often a limiting factor
2) In terrestrial ecosystems, oxygen is a limiting factor; in aquatic ecosystems, it is almost always available
3) In both terrestrial and aquatic ecosystems, oxygen is a limiting factor
45. Match
METABOLIC FEATURES GROUP OF ORGANISMS
A) release of oxygen into the atmosphere 1) autotrophs
B) use of energy contained in food for the synthesis of ATP 2) heterotrophs
C) the use of ready-made organic substances
D) synthesis of organic substances from inorganic ones
D) use of carbon dioxide for nutrition
Block C. Give a detailed answer to the questions
1. How does the land-air environment differ from the water environment?
2. The rate of photosynthesis depends on limiting factors, including light, carbon dioxide concentration, and temperature. Why are these factors limiting for photosynthesis reactions?
3. What are the manifestations of morphological, physiological and behavioral adaptations to environmental temperature in warm-blooded animals?
4. What changes in biotic factors can lead to an increase in the number of naked slugs that live in the forest and feed mainly on plants?
5. You can sometimes see a large number of earthworms on the soil surface. Explain under what meteorological conditions this occurs and why.
ABIOTIC FACTORS, various factors not related to living organisms, both beneficial and harmful, found in the environment surrounding living organisms. These include, for example, the atmosphere, climate, geological structures, amount of light,... ... Scientific and technical encyclopedic dictionary
Environments, components and phenomena of inanimate, inorganic nature (climate, light, chemical elements and substances, temperature, pressure and movement of the environment, soil, etc.), directly or indirectly affecting organisms. Ecological encyclopedic... ... Ecological dictionary
abiotic factors- abiotiniai veiksniai statusas T sritis ekologija ir aplinkotyra apibrėžtis Fiziniai (temperatūra, aplinkos slėgis, klampumas, šviesos, jonizuojančioji spinduliuotė, grunto granulometrinės savybės) ir cheminiai (atmosferos, van dens, grunto cheminė… Ekologijos terminų aiškinamasis žodynas
Factors of inorganic nature affecting living organisms... Large medical dictionary
Abiotic factors- factors of the inorganic, or nonliving, environment in the group of environmental adaptation factors operating among biological species and their communities, divided into climatic (light, air, water, soil, humidity, wind), soil... ... The beginnings of modern natural science
ABIOTIC FACTORS- Factors of the inorganic environment affecting living organisms. These include: the composition of the atmosphere, sea and fresh waters, soil, climate, as well as zoohygienic conditions of livestock buildings... Terms and definitions used in breeding, genetics and reproduction of farm animals
ABIOTIC FACTORS- (from the Greek a negative prefix and biotikos vital, living), inorganic factors. environments affecting living organisms. K A. f. include the composition of the atmosphere, sea. and fresh water, soil, climate. characteristics (temperature pa, pressure, etc.). The totality... Agricultural encyclopedic dictionary
abiotic factors- (from the Greek a negative prefix and biōtikós vital, living), factors of the inorganic environment that affect living organisms. K A. f. include the composition of the atmosphere, sea and fresh waters, soil, climatic characteristics (temperature... Agriculture. Large encyclopedic dictionary
ABIOTIC FACTORS- environment, a set of conditions in the inorganic environment that affect the body. Chemical a.f.: chemical composition of the atmosphere, sea and fresh waters, soil or bottom sediments. Physical a.f.: temperature, light, barometric pressure, wind,... ... Veterinary encyclopedic dictionary
Environments, a set of conditions in the inorganic environment that affect organisms. A. f. are divided into chemical (chemical composition of the atmosphere, sea and fresh water, soil or bottom sediments) and physical, or climatic (temperature, ... ... Great Soviet Encyclopedia
Books
- Ecology. Textbook. RF Ministry of Defense stamp
- Ecology. Textbook. Grif Ministry of Defense of the Russian Federation, Potapov A.D.. The textbook examines the basic principles of ecology as a science about the interaction of living organisms with their habitat. The main principles of geoecology as a science about the main...
Test "Abiotic environmental factors"
1. Signal for the beginning of the autumn migration of insectivorous birds:
1) decrease in ambient temperature
2) reduction of daylight hours
3) lack of food
4) increase in humidity and pressure
2. The number of squirrels in the forest zone is NOT affected by:
1) alternation of cold and warm winters
2) harvest of fir cones
3) number of predators
3. Abiotic factors include:
1) competition between plants for light absorption
2) the influence of plants on animal life
3) temperature change during the day
4) human pollution
4. A factor limiting the growth of herbaceous plants in a spruce forest is a disadvantage:
4) minerals
5. What is the name of a factor that significantly deviates from the optimal value for the type:
1) abiotic
2) biotic
3) anthropogenic
4) limiting
6. The signal for the onset of leaf fall in plants is:
1) increase in environmental humidity
2) reduction in daylight hours
3) reducing environmental humidity
4) increase in ambient temperature
7. Wind, precipitation, dust storms are factors:
1) anthropogenic
2) biotic
3) abiotic
4) limiting
8. The reaction of organisms to changes in day length is called:
1) microevolutionary changes
2) photoperiodism
3) phototropism
4) unconditioned reflex
9. Abiotic environmental factors include:
1) boars tearing up roots
2) locust invasion
3) formation of bird colonies
4) heavy snowfall
10. Of the listed phenomena, daily biorhythms include:
1) migration of marine fish to spawn
2) opening and closing of flowers of angiosperms
3) bud bursting in trees and shrubs
4) opening and closing shells in mollusks
11. What factor limits plant life in the steppe zone?
1) high temperature
2) lack of moisture
3) absence of humus
4) excess ultraviolet rays
12. The most important abiotic factor that mineralizes organic residues in the forest biogeocenosis is:
1) frost
13. Abiotic factors that determine population size include:
1) interspecific competition
3) decreased fertility
4) humidity
14. The main limiting factor for plant life in the Indian Ocean is the lack of:
3) mineral salts
4) organic substances
15. Abiotic environmental factors include:
1) soil fertility
2) a wide variety of plants
3) presence of predators
4) air temperature
16. The reaction of organisms to the length of the day is called:
1) phototropism
2) heliotropism
3) photoperiodism
4) phototaxis
17. Which factor regulates seasonal phenomena in the life of plants and animals?
1) temperature change
2) air humidity level
3) availability of shelter
4) length of day and night
Answers: 1 – 2; 2 – 1; 3 – 3; 4 – 1; 5 – 4;
6 – 2; 7 – 3; 8 – 2; 9 – 4; 10 – 2; 11 – 2;
12 – 2; 13 – 4; 14 – 1; 15 – 4; 16 – 3;
17 – 4; 18 – 4; 19 – 1; 20 – 4; 21 – 2.
18. Which of the following inanimate factors most significantly influences the distribution of amphibians?
3) air pressure
4) humidity
19. Cultivated plants grow poorly in swampy soil because it:
1) insufficient oxygen content
2) methane formation occurs
3) excess content of organic substances
4) contains a lot of peat
20. What device helps cool plants when the air temperature rises?
1) decrease in metabolic rate
2) increase in the intensity of photosynthesis
3) decrease in breathing intensity
4) increased water evaporation
21. What adaptation of shade-tolerant plants ensures more efficient and complete absorption of sunlight?
1) small leaves
2) large leaves
3) thorns and thorns
4) waxy coating on the leaves