The current state of vegetation lesson ecology. The current state and protection of vegetation - Knowledge Hypermarket. Rational use and protection of vegetation

As of early 2010, according to International Union nature conservation ( IUCN), about 320 thousand species of plants were described, of which about 280 thousand species of flowering, 1 thousand species of gymnosperms, about 16 thousand bryophytes, about 12 thousand species of higher spore plants (lycosformes, paporiformes, horsetails). However, this number is increasing as new species are constantly being discovered.

Of all the plant resources of the Earth, forests are the most important in nature and human life. They suffered the most from economic activity and became the object of protection earlier than others.

Deforestation

Deforestation began at the dawn of human society and increased as it developed, as the demand for timber and other forest products increased rapidly. Over the past 10 thousand years, 2/3 of forests have been reduced on Earth. Over historical time, about 500 million hectares have turned from forests into barren deserts. Forests are being destroyed so quickly that the areas of clearings significantly exceed the areas of planting trees. To date, in the zone of mixed and widely deciduous forests about 1/2 of their original area has been reduced, in the Mediterranean subtropics - 80%, in the zones of monsoon rains - 90%.

On the Great Chinese and Indo-Gangetic plains, forests have survived only on 5% of their former distribution. Tropical rainforests are being cut down and shrinking at a rate of about 26 hectares per minute, and there are fears that they will disappear in 25 years. Cut areas of wet rainforest are not restored, and in their place unproductive shrub formations are formed, and with strong soil erosion, desertification occurs.

In connection with deforestation, the water content of rivers is reduced, lakes dry up, the level of groundwater drops, soil erosion increases, the climate becomes more arid and continental, droughts and dust storms often occur.

Vegetation protection

Protection and restoration of forests. The main task of forest protection is their rational use and restoration. It is important to increase the productivity of forests, protect them from fires and pests.

1 . With proper forest management, felling in some areas should be repeated after 80-100 years, when the forest reaches full maturity. In many central regions European Russia they have to return to recutting much earlier. Exceeding the felling norms has led to the fact that in many areas the forests have lost their climate-forming and water-regulating value. The proportion of small-leaved forests has increased significantly.

2 . Part of the wood is lost during timber rafting. In some years, so many logs are carried into the northern seas by the rivers that in the Scandinavian countries there are special ships for catching them and industries for processing them. At present, the irrational alloying of logs without combining them into rafts on major rivers ah forbidden. Near the enterprises of the woodworking industry, factories for the production of furniture from fibreboard are being built.

3. The most important condition for the conservation of forest resources is timely reforestation. Only a third of the forests cut down annually in Russia are restored naturally, the rest require special measures for their renewal. At the same time, on 50% of the area, only measures to promote natural regeneration are sufficient, on the other, sowing and planting trees are necessary. Weak reforestation is often associated with the cessation of self-seeding, the destruction of undergrowth, soil destruction during logging and timber transportation. Clearing them of plant rags, branches, bark, needles remaining after felling has a positive effect on the restoration of forests.

Description:

The purpose of the presentation is to explain to students the importance of the problem raised, to consider all aspects and causes of its occurrence, to suggest methods for combating the deterioration of vegetation.

The presentation presents various flowcharts, theoretical information is supplemented with illustrations, and current statistical data of recent studies are displayed.

The presentation material calls for environmental responsibility, the students will form an objective view of the issue under study.

The presentation material consists of the following sections:

• Forests as a plant resource of our planet.
• The use of wood in the global industry.
• Causes and consequences of deforestation.
• Ways to solve problems.
• Protection of Nature.

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• Date of creation of the material: February 27, 2013
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Rational use and protection of vegetation.

Impossible to imagine the world without plants - our faithful and silent green friends. Every breath of air, every crumb of food is given to us by plants, they help us feel the joy of communicating with nature, its charm and beauty. Caring for silent and beautiful plants, a person himself becomes cleaner and kinder.

Green plants create conditions on Earth for the existence of all living organisms. They release oxygen, which is necessary for respiration, and serve as the main source of food for all animals. Even the most bloodthirsty predator depends on the plants that feed on its prey.

Covering the Earth with a green carpet, plants protect and preserve it. Thickets of plants create their own climate, softer and more humid, because the foliage resists the withering action of the sun's rays. Plant roots hold and hold the soil together. Where the forest has been preserved, the surface of the Earth is not disfigured by ravines.

Plants are the primary source of existence, prosperity and development of life on Earth, and primarily due to their ability to carry out photosynthesis. Photosynthesis takes place almost everywhere on our planet, and therefore its total effect is colossal. In the process of photosynthesis, green plants create organic substances from carbon dioxide and water and serve as a source of valuable food (grains, vegetables, fruits, etc.), raw materials for industry and construction.

Formation of the gas composition of atmospheric air, as is known, is also directly dependent on plants. Green plants in the process of photosynthesis release about 510 tons of free oxygen per year.

Plants are involved in the formation of humus, which is the most essential part of the soil, ensures its high fertility. In addition to carbon, hydrogen and oxygen, the molecules of many organic substances include atoms of nitrogen, phosphorus, sulfur, and often other elements (iron, cobalt, magnesium, copper). All of them are extracted by plants from the soil or aquatic environment in the form of salt ions, mainly in the oxidized form. Mineral salts are not washed out of the surface layers of the soil, since the vegetation constantly absorbs part of the mineral substances from the soil and transfers them to animals for food. Animals, like plants, after dying, transfer minerals back to the soil, from where they are again absorbed by plants.

Vegetation renders big influence on the climate, water bodies, wildlife and other elements of the biosphere with which it is closely interconnected.

The importance of vegetation in human life is great. First of all, vegetation represents the necessary environment for human life. Wild flora is an invaluable genetic fund in breeding work when creating new varieties of agricultural crops. Most of the plants that provide about 90% of the world's food today came about through domestication of wild plants.

For many centuries, people have been extracting from plants a variety of medicinal substances that are so necessary in medical and veterinary practice. Over 1000 types of products are in circulation on the modern world market. medicinal plants. Among them are preparations from the root of life - ginseng, eleutherococcus, lily of the valley, spring adonis.

Plants serve as the main food base for domestic and many wild animals. They participate in the formation of minerals, protect the surface of the Earth from destruction by water flows and wind, and from falling asleep with sands of fertile land.

Plants Detoxify in Different Ways harmful substances. Some of the harmful substances are bound by the cytoplasm of plant cells and become inactive, while others undergo transformations in plants to non-toxic products and participate in metabolism.

To combat harmful microorganisms, plants have developed a number of substances that can suppress their activity. These include antibiotics (penicillin, streptomycin, tetracycline, etc.) and phytoncides. Onion and garlic have strong bactericidal properties. In this regard, they have long been used as therapeutic agents. One juniper plant releases 30 g per day volatile substances, and one hectare is the amount of phytoncides that is sufficient to clean all streets from microbes big city. Vegetation for a person is also a source of aesthetic pleasure, providing him psychological impact.

Of all the plant resources of the planet, the most important in the life of nature and man is forests. They suffered the most from economic activity and were the first to become objects of protection.

The forest is a wealth of nature, the importance of which is difficult to overestimate. In addition to its enormous and diverse economic importance, the forest acts as an extremely important geographic factor, which has a great influence on other types of landscapes and on the biosphere as a whole.

The forest is called green gold, referring to its special value and universality. economic importance. It is a source of wood, food, technical and medicinal raw materials.

Exceptionally high ecological role forests. It is one of the most important regulators of the moisture cycle on Earth, prevents water and wind erosion, maintains soil fertility, preventing flushing and the formation of ravines, restrains the movement of sands, and alleviates the effects of droughts. Forests affect the gas balance and composition of the atmosphere, water and thermal regime earth's surface, regulate the abundance and diversity of the animal world. Forest cover is interrelated with climate: it reduces the force of the wind, softens high and low temperatures, accumulates moisture. Equally important is the water protection role of forests. It contributes to the translation precipitation into the soil and groundwater, thereby regulating hydrological regime rec. Today, the forest is considered as the leading factor in energy and mass transfer on Earth. The forest cover of the planet is a single global system of the world's forest, which is the most important component of the biosphere as a whole.

Their rational use is based on the ecological laws of conservation, restoration and change. plant communities.

Wood is used in various industries National economy, it serves as a source of chemicals obtained during the processing of wood, bark, needles. The forest supplies raw materials for over 20 thousand articles and products. Almost half of the wood produced in the world is used for fuel, and a third goes to production building materials. The lack of wood is acutely felt in all industrial developed countries.

IN Lately great importance is attached to the sanitary-hygienic, balneological and recreational role of forests. In Russia, as in some other regions of the world, the "non-resource" possibilities of green spaces have become widely used: these are green areas of cities, natural or National parks, resort areas.

The beneficial effect of pine forests on tuberculosis patients, caused by the disinfecting properties of terpenes, is well known. Many coniferous trees emit special substances - phytoncides that kill pathogens. Tree plantations purify the air of cities and towns from dust, harmful gases, soot, protect residents from noise. The dust content on a green street is 3 times less than on a street without trees.

Some rare and valuable breeds trees are in danger of extinction. All this threatens with exceptionally dangerous economic and environmental impact.

The sharp reduction of forests on the planet has led not only to the depletion of forest capital. It caused severe consequences for people, such as shallowing of rivers and lakes, destructive floods, mudflows, soil erosion, and climate change.

The forest is an excellent accumulator of moisture, delays snowmelt, blocks the way to external and rain water, contributing to the replenishment of groundwater and the normal flow of flat and mountain rivers. With the destruction of forests, destructive spring floods and summer floods of rivers arise. Spring and rain waters, without encountering obstacles in the form of forests, quickly flow down ravines into rivers and then into the seas. As a result, groundwater is poorly replenished, its level drops so much that it can no longer make up for the loss of water in rivers and lakes, which occurs due to evaporation in summer period. As a result, reservoirs begin to shallow, many rivers become unnavigable.

Floods, the origin of which is associated with the destruction of forests, are widespread in many parts of the world and bring innumerable disasters.

A particularly devastating consequence of deforestation is soil erosion, which is widespread throughout the globe and became the scourge of agriculture.

Finally, the destruction of forests over vast areas worsens the climate, makes it drier and continental, contributes to increased winds and the spread of hot winds, the appearance of droughts, etc., which negatively affects agriculture.

Russia is a country of forests. Russia's forests account for 22% of the world's forests. The total area of ​​the forest fund lands of the Russian Federation, as of 01.01.98, was 1,172.9 million hectares, or 69% of the territory of Russia.

For the purpose of proper forest management, forests of national importance are divided into three groups.

To the woods first group forests, the main purpose of which is to perform water protection, protective, sanitary and hygienic, recreational and other functions, as well as specially protected natural areas

To the woods second group include forests in regions with a high population density and a developed network of land transport routes; forests performing water protection, protective, sanitary-hygienic, health-improving and other functions of limited operational significance, as well as forests in regions with insufficient forest resources, the conservation of which requires restriction of the forest management regime.

To the woods third group include forests of densely forested areas, which are primarily of operational importance.

The forest has always attracted a large number of hunters, pickers of mushrooms and berries, as well as those who just want to relax. Recently, with the development of mass tourism in our country, the army of forest visitors has grown so much that it has become a factor that cannot be ignored when protecting the forest.

Many millions of people in summer time go to the suburban forests to spend their weekends or holidays in nature; many thousands of tourists make trips along the same routes. In some places in the suburban forests you can find entire tent cities with a large population.

A huge army of visitors to the forest makes major changes in his life. To set up tents, a large number of young trees are cut down, not only dry wood is used for fires, but also growing healthy trees.

Not all tents are set up in a clean place, very often undergrowth is cut down at the site of their installation, removed, broken and ruined by young growth. The latter perishes under axes, bonfires, and simply under the feet of numerous visitors to the forest.

Forests frequented by tourists are littered so thoroughly with tin cans, bottles, rags, paper, etc. that this has a negative effect on natural reforestation. The latter has become completely impossible over the past few years in the places of bonfires and in densely trampled areas around them, the total area of ​​\u200b\u200bwhich in the forest is very significant.

Finally, forest visitors often cause harm to the trees themselves. Many trees (especially near the tents) bear traces of large and small wounds filled with resin. On some of them, the resin is burned out, and a significant part of the trunk is scorched by fire. These trees are candidates for desiccation.

These actions of organized and unorganized tourists and other visitors to the forest are very great harm forest resources and especially forests located around cities and industrial centers. The negative impact of tourists on forests and areas farther from the cities, where the number of tourists is increasing every year, is increasingly felt.

The presence in the forests of a large number of people making fires, smoking, setting fire to the resin on the trunks coniferous trees etc. is dangerous in terms of fire.

The use of the forest fund for cultural, recreational, tourist and sports purposes is organized in specially allocated green areas in the forest, including in the forest park parts of green areas. For these purposes, national and natural parks, zones of sanitary protection of resorts, natural monuments, as well as special especially protective forest areas.

The recreational value of forests located in places with developed industry, near large cities, is growing rapidly. The recreational value of forests sometimes exceeds the value of the timber obtained from them. The forest has always attracted hunters, mushroom pickers, berry pickers, and tourists. With the accumulation of vacationers in the forests, a recreational load arises. This has a bad effect on the continuation of the natural development and normal existence of forests, biogeocenoses. If a forest area is badly damaged by soil trampling, it must be excluded from use for 3-5 years or more.

One of the important forms of struggle for the protection of recreational forests is the widespread environmental propaganda among tourists and the public. All fire safety regulations must be followed carefully. Walking, resting and picking mushrooms and berries in young forest stands are strictly prohibited. A large role in organizing and coordinating this work belongs to the rural, district and city administrations. In addition to tourism organizations, regional and district councils should take part in this work. voluntary societies conservation, as well as schools. It is necessary to achieve such a situation that all visitors to the forest not only know the rules of behavior in the forest, but also strictly observe them. Forests are people's wealth, which everyone is obliged to treat with care, like any other socialist property.

With the development of urbanization, green spaces in cities are of great importance. Green spaces - trees and shrubs, flowers and herbaceous vegetation, elements of improvement of green areas - are effective tool environmental protection of the city. Any form of economic activity that causes irreparable harm to the green fund of the city is unacceptable.

Forest protection implies, first of all, their rational use and reproduction, which is the main task of our forestry. The main measures taken by forestry for the rational use of forests include the use of scientifically based calculation and distribution of the logging fund, the economical and full use of the resulting wood, the protection of forests from fires, pests and other adverse natural factors.
Reforestation is carried out by applying measures for reforestation and increasing the productivity of forest plantations.

Scientifically substantiated calculation and distribution of the logging fund are of paramount importance in the protection of forests.

Of no small importance in the conservation of the forest is its careful use. Unfortunately, the loss of wood during its harvesting, transportation and use reaches such proportions that no other industry, except for the forest industry, allows for its raw materials.

One of the most important conditions for the reproduction of forest resources is reforestation. Reforestation measures, together with scientifically substantiated calculation and placement of the logging fund, form the basis of forest protection.

In addition to the restoration of forests, increasing their productivity is of great importance in the matter of protection. At high productivity, smaller forest areas can be allocated for felling than at low productivity.

The productivity of forests largely depends on the efficiency of reforestation. In addition, the increase in productivity is achieved by caring for the forest, replacing tree plantations with more productive species, and draining swamps.

The main form of forest care is the so-called thinning.

Carrying out thinnings sets the following tasks: to provide the desired composition of species in the forest, to form a forest from trees of a higher quality, to accelerate growth and increase the productivity of the forest, to obtain additional wood. Along with this, thinning makes it possible to improve the sanitary condition of the forest by removing infected trees and to prevent snowfall and snowfall of trees in young stands.

In addition, thinning enhances the water-protective, water-regulating, and soil-protective properties of the forest.

Work on the reconstruction of forests through the introduction of highly productive tree species into them is taking on an increasing scale in our country. The replacement of low-value soft-leaved forests with more valuable coniferous forests is being especially intensively carried out.

The productivity of forests and the quality of wood increase sharply as a result of the drainage of marshes. The forests of many, especially the northern, regions of the country are swamped over large areas. Wet forests give low growth and poor wood quality. Draining wetland forests results in increased growth rates and improved forest quality.

Forest fires, as noted above, cause enormous damage to forest resources. Beyond Doom a large number wood, forest animals and useful plants, fires also cause damage by the fact that the forests that regenerate after them take on a different character and are usually less valuable. Burn most often coniferous forests that have the highest value.

Combat forest fires our country attaches great importance national importance. A whole system of measures has been developed, which are divided into three groups: preventive, sentinel guard service and fire fighting.

Preventive measures are of particular importance. These include fire-fighting technical propaganda among the population, cleaning cutting areas and the fight against clutter in the forest, fire-fighting forests.

The patrol guard service has the task of timely detection of fires. This service consists of regular walks around the forest, observation of the latter from fire towers, and air patrols.

Direct fire fighting is carried out by various methods. The effectiveness of this struggle has increased significantly due to the use of modern technology.

The damage caused to the forest by various pests and diseases is great. The economic damage from fungal diseases is great, in some cases it exceeds the damage caused by harmful insects.

Therefore, we attach great importance to the fight against pests and diseases. This struggle is carried out by various methods and technical means. But, no method is universal. The struggle can be successful only when it is carried out systematically by all available methods and means.

The main methods of pest and disease control include forestry activities, mechanical, chemical and biological.

Forestry activities are aimed at maintaining forest plantations in a healthy state by timely removal of weakened, infected and diseased trees, cleaning of windbreak, rags and logging residues, compliance with the rules for storing harvested wood in the forest, right choice cutting methods, etc.

mechanical method includes measures of direct extermination of insects using the simplest mechanical devices or manually.

chemical method pest control is the most widespread due to its ease of use, efficiency, relative cheapness and the ability to use it over vast areas.

biological method combat is based on the use natural enemies pests that regulate the number of the latter in nature.

Recently, intensive and successful development microbiological method forest pest control by using entomopathogenic fungi, bacteria and viruses that cause disease and death of pests.

Work on the protection of forests and other vegetation from chemical and radioactive contamination is still being carried out on an insufficient scale, and mainly in relation to the green areas of large industrial centers. It needs to be expanded and strengthened.

Meadows and pastures are of great importance in providing fodder for farm animals. Herbs of natural meadows are the most complete food, rich in vitamins, microelements and mineral salts. Meadows and pastures occupy a significant place among other agricultural lands ...

About 60% of plant species grow in meadows and pastures. However, in a number of cases, these lands are still not used rationally enough and require radical improvement to increase hayfields and pastures.

Floodplain meadows are often filled with silt, sand, and debris during floods; like the upland ones, they are covered with tussocks, shrubs, in places they have excessive moisture. The productivity of meadows also falls as a result of their too intensive use for pastures.

1) Clearing and leveling the surface (cleaning of shrubs, stones, debris, deadwood, destruction of bumps);

2) Improvement and regulation water regime soils;

3) Preservation (and, if necessary, creation) of coastal shrub strips in the floodplains of large rivers, as a means of preventing floodplain meadows from being covered with sand;

4) Fighting poisonous plants;

5) Surface application of organic and mineral fertilizers;

6) Sometimes sowing seeds.

In increasing the productivity of meadows, the best results are obtained by alternate hay-pasture use. However, early spring grazing followed by haying reduces the yield of meadows by half.

Pastures are the most affected by overgrazing.

Lichen pastures (reindeer moss) are of great importance for reindeer husbandry. Lichens are an essential plant component to maintain natural biocenoses tundra. The impoverishment of the tundra as a result of overgrazing of animals changes the nature of vegetation and worsens the quality of pastures.

In some cases, a certain amount of damage to the herbage is caused by strongly multiplied rodents, especially mouse-like ones.

The protection of pastures is, first of all, the prevention of overgrazing in combination with some agricultural measures to improve the herbage.

The protection and rational use of economically valuable plants consists in their properly organized collection, in which the natural reserves of plants should not be depleted. This is especially important for those species in which underground parts go into production. Currently, the procurement of raw materials is carried out by many organizations without proper control. It is necessary to establish control over the quantitative and qualitative use of stocks of economically valuable plant species.

In the CIS, too, many plant species have become rare. These include water chestnut, lotus (preserved only in the Volga delta in the form of several clumps in Azerbaijan and on Lake Khanka), aldrovandus (insectivorous plant), iron tree, silk acacia, chestnut-leaved oak, Hyrcanian boxwood, Aldar pine, palmate sycamore, turanga , pistachio, yew, holly, etc.

Rare and endangered species are protected in several ways.

The first way is the issuance of appropriate legal provisions prohibiting the use of these species. It is important that the ban covers all rare species, and that this ban is practically implemented.

The second is security rare species in reserves and sanctuaries.

The third is the creation of collection sites and reserves in the network of botanical gardens and other scientific institutions. Transferred to collection beds, plants can be maintained in culture indefinitely for a long time and be a necessary reserve for various purposes.

The success of vegetation protection largely depends on the participation of the general population in this matter. Environmental education among the population, in particular, propaganda scientific knowledge about flora and its significance for humans.

Of fundamental importance for the protection of forests is their division into categories and groups according to the degree of protection.

The forests of the first group include:

Forbidden strips along the banks of rivers, lakes, reservoirs and other water bodies; forbidden strips of forests that protect the spawning grounds of valuable commercial fish;

Anti-erosion forests; protective forest belts along the iron and highways;

Forests of green areas of cities, others settlements and economic objects; forests of the first and second belts of zones of sanitary protection of water supply sources; forests of the first, second and third zones of districts of sanitary protection of resorts;

especially valuable woodlands; forests of scientific or historical importance; walnut-commercial zones, forest-fruit plantations, etc.;

Forests of reserves, national and natural parks, protected forest areas, etc.

In addition, in the forests of all groups, special protective areas with a limited forest use regime can be identified, including coastal and soil protection forest areas along the banks of water bodies, slopes of ravines and gullies, habitats of rare and endangered wild animals and plants, etc.

1. Explain why on the rivers along which the forest is cut down, the water level is not constant: if there is little precipitation, the level drops significantly; Why do floods rarely occur on forest rivers?

(Answer: forest vegetation reduces the speed of water passage from the catchment area into the rivers hundreds of times. As a result, water (through underground and surface flows) enters the rivers evenly, which excludes floods or shallowing of water flows.)

2. Mudflow is a dangerous natural phenomenon, which is a turbulent mud flow in the mountains, caused by snowmelt or heavy rains. Mudflows carry with them a lot of stones and boulders of enormous size and can produce enormous destruction with human casualties. Why mudflows are practically absent in places where the population is low? Why is the likelihood of mudflows very high in places where forests are cut down in the mountains and (or) domestic animals are grazed?

(Answer: contemporary human activity in the mountains is associated with deforestation and intensive destruction of vegetation (grazing, construction of roads and structures, etc.). Bare and unprotected soil is easily washed away during heavy floods or heavy rains, which leads to the formation of mudflows. The more intense and uncontrolled human activity in the mountains, the higher the likelihood of mudflows.)

3. Why does it take longer for the snow to melt in the forest than in the field? What does this mean for plants; for the hydro regime of fields, forests, rivers?

(Answer: there is more shade in the forest, so it is cooler. Longer melting of spring snow in the forest allows the soil to accumulate more moisture. The microclimate of the forest contributes to less evaporation - as a result, more water. Prolonged snowmelt does not contribute to the rapid washing of soil and litter, which is observed in the fields.)

4. The Red Book of Russia contains:

a) blue cornflower;
b) May lily of the valley;
c) lady's slipper;
d) medicinal chamomile;
e) Hypericum perforatum.

(Answer: V . )

5. Are the statements correct (yes or no):

a) over the past 10 thousand years, 2/3 of the forests on the planet have been destroyed by man;
b) now the area of ​​felling significantly exceeds the area of ​​planting trees;
c) cut areas of wet rainforest fairly quickly restored to their original composition;
d) desertification cannot occur as a result of deforestation;
e) the greatest number of fires occurs due to natural causes;
f) biological control measures are the most ineffective, do not last long;
g) the most effective protection rare plants in parks and resort areas;
h) listing a species in the Red Book is a signal of a danger that threatens its existence;
i) vegetation, including forests, are non-renewable Natural resources;
j) the economic damage caused to the forest by fires exceeds the damage from pests and diseases.

(Answer: "yes" - a, b, h, k; "no" - c, d, e, f, f, i.)

6*. Ecologists believe that in the northern regions the forest can be cut down and taken out only in winter through deep snow. Why?

(Answer: in this case, the soil cover is much less disturbed - the litter and the grassy layer of plants are not destroyed, potholes, ruts are not formed that change the hydrological regime and contribute to soil erosion. In the northern regions, where the soil layer is formed for a long time and does not reach a significant thickness, compliance with these conditions is of particular importance.)

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