How does Russia compare to other countries with significant forest reserves? Scientists from the All-Russian Research Institute of Forestry and Mechanization were concerned with this issue. forestry(VNIILM), who conducted their own analysis of the processes occurring in Russia and abroad. As a basis for the study, the scientists used the FAO (Food and Agriculture Organization of the United Nations) Global Forest Resources Assessment databases.
The list of countries chosen for comparison with Russia includes 14 states and reflects the diversity of natural and climatic conditions. Of course, many of the data underlying the study are controversial in scientific world, since the calculation methods used in different countries often do not coincide, and therefore do not allow for correct comparative analysis. It is no coincidence that VNIILM specialists turned to the database of an international organization, which, although not indisputable, makes it possible to compare different countries V unified system coordinates The result is the following picture.
The total forest area of the Earth is just over 4 billion hectares. The top three richest forest countries are Russia, Brazil and Canada. Moreover, the forested areas in Russia are 1.5 times larger than the area of the Brazilian jungle.
If we talk about how they change forested areas, then one of the most dynamic countries is China. From 2000 to 2010, the forest area here increased by 30 million hectares. But Brazil lost 26 million hectares of forest during this period. Russian Federation demonstrates rare stability: over the past 20 years the numbers have not changed either positive or negative.
“The high level of wood imports into China has increased pressure on natural forests in neighboring countries,” Russian scientists say. As a result, for 2000-2005 the country South East Asia lost more than 14 million hectares of virgin forests, which were replaced by forest plantations. According to forecasts, if nothing changes, then in 10 years the virgin forests of Southeast Asia may be completely destroyed.
The universal assessment of forest resources at the national level is forest cover. Finland boasts the maximum forest cover (73%), followed by Sweden (69%) and Malaysia and Brazil (62%). The situation is worse than others in Uruguay (10%). Russia, with a forest cover of 49%, is in the middle of the list. Over the past 20 years, forest cover has declined in Argentina, Australia, Brazil, Indonesia and Malaysia. In other countries, on the contrary, this figure has increased, especially over the past five years.
By latest estimates, the global timber reserve is 527 billion cubic meters. Brazil leads the way with a reserve of 126 billion cubic meters, followed by Russia (81.5 billion cubic meters) and the United States (47 billion cubic meters). These top three account for 60 percent of the world's timber reserves. While in other countries this figure shows stability, in Brazil it has increased by 64 percent over the past five years. VNIILM specialists attribute this to the completion of the forest inventory process, carried out according to the FAO methodology. Most likely, according to VNIILM experts, after the completion of the first stage of the state forest inventory in Russia, this figure will also shoot up.
The largest reserves of wood per 1 hectare were recorded in New Zealand (434 cubic meters), Germany (315 cubic meters) and Brazil (243 cubic meters). Russia, with an indicator of 101 cubic meters per 1 hectare, ranks ninth. As Russian scientists note, Germany’s excellent forestry school and high quality forest crops created after the Second World War.
Preservation biological diversity usually associated with the area of specially protected natural areas. In general, the area of protected areas on the planet increased from 1990 to 2010 by 94 million hectares. But, for example, in Indonesia and Malaysia, on the contrary, it decreased. The largest forest areas under state protection are in Brazil, where protected areas occupy 89.5 million hectares. In Russia, according to international organizations, protected areas occupy 17.5 million hectares. But these are only parks, nature reserves and wildlife sanctuaries of federal significance. If we take into account all forests with restrictions on forest use, this is almost 25 percent of the entire forest fund area of Russia.
The state of the forestry industry is characterized by the volume of timber harvested. For many years, the United States remained the leader in this issue. Against the backdrop of the global economic crisis, America and European countries are experiencing a decline in logging, and in the United States they decreased by 59 percent. The crisis influenced the change of leader, which in 2010 became India with a timber harvest of 332 million cubic meters. The United States, slightly behind, takes second place, while Russia traditionally holds fifth position.
But if everything is not so bad with volumes, then the efficiency of logging is “limping” on both legs. While in Uruguay 6.9 cubic meters of wood are removed from one hectare, in Germany and India - 4.9 cubic meters, in Sweden 2.6 cubic meters, in Finland 2.3, in Russia - only 0.2 cubic meters. Only Australia demonstrates a similarly low efficiency rate. According to Russian scientists, main reason such a situation - a limited number of economically interesting forests, which leads to the need to increase logging areas.
But we are still the first in some things. According to FAO, it is Russia that has the most large area forests (71.4 million hectares) performing protective functions. China (more than 60 million hectares) and Brazil (42 million hectares) help us maintain the ecological well-being of the planet.
BIOLOGICAL RESOURCES
The Earth's biomass is created by plant and animal organisms.
Plant resources are represented by both cultural and wild plants. There are almost 6 thousand species cultivated plants. But the most common types of agricultural crops on Earth are only 80-90, and the most common are only 15-20: wheat, rice, corn, barley, sweet potato, soybeans, etc.
Among wild plants it predominates forest vegetation, forming forest resources. Like land, these are exhaustible but renewable resources of multi-purpose use. World forest resources are characterized by three main indicators: the size of forest area (4.1 billion hectares), forest cover (31.7%) and standing timber reserves (330 billion m3), which, due to constant growth, increase annually by 5.5 billion m3. It would seem that in these conditions it is premature to talk about the threat of a shortage of forest resources. But this is not true at all.
Wood has long been widely used as a construction and ornamental material; This is all the more true for our time. And today the demand for firewood is growing, and at least 1/2 of all wood harvested in the world is used for these purposes. Finally, for thousands of years, starting with the Neolithic, when agriculture arose, forests were reduced to arable land and plantations. In the last two hundred years alone, the forest cover of the earth's land has halved and deforestation has become alarming. It is associated with an increase in soil erosion and a reduction in oxygen reserves in the atmosphere.
The world's forest area decreases annually by at least 20 million hectares, or 0.5%. World timber harvesting in the near future may reach 5 billion m 3 . This means that its annual growth will actually be fully used.
The forests of the world form two huge belts - northern and southern.
Table 15. Distribution of forest area by large regions.
The northern forest belt is located in the zone of temperate and partly cold and subtropical climates. It accounts for 1/2 of all forests in the world and the same part of the timber supply. The main logging operations are carried out here, especially valuable wood coniferous species. Despite intensive exploitation, thanks to reforestation and afforestation work (in the USA, Canada, Finland, Sweden) total area forests in the northern zone are not decreasing.
The southern forest belt is located mainly in the tropical and equatorial climates. It accounts for 1/2 of all forest areas and the total wood supply. Previously, it was used mainly for firewood, in Lately Exports to Japan have increased many times, Western Europe, USA. High damage The forests of the southern belt are also damaged by the slash-and-burn farming system, which has been going on for many hundreds of years, and extensive grazing. All this leads to catastrophically rapid deforestation of this belt.
Wet evergreens rainforests still occupy more than 1 billion hectares, with more than half of their area in Latin America. However, Latin America and Asia have already lost 40% of such forests, and Africa - 50%. Scientists believe that these forests are under threat of complete destruction by the middle of the 21st century. Big works on conservation tropical forests started under the leadership of the UN, but so far they have not brought the desired results. Therefore, measures for the rational use of forest resources continue to remain extremely relevant.
Table 16. The most and least forested countries in the world
|
Most wooded countries |
Forest cover, % |
Least wooded countries |
Forest cover, % |
|
Suriname |
Oman |
||
|
Papua New Guinea |
Kuwait |
||
|
Guyana |
Central African Republic |
||
|
Gabon |
Saudi Arabia |
||
|
DR Congo |
Jordan |
||
|
Finland |
Iceland |
||
|
Cambodia |
Egypt |
||
|
DPRK |
UAE |
||
|
Sweden |
Haiti |
||
|
Japan |
Niger |
||
|
The Republic of Korea |
Algeria |
||
|
Laos |
Afghanistan |
||
|
Brazil |
South Africa |
||
|
Indonesia |
Syria |
||
|
Guinea |
Countries with nai large sizes forest areas
Russia (765.9 million hectares), Canada (494.0), Brazil (488.0), USA (296.0), DR Congo (former Zaire), Australia, China, Indonesia, Peru, Bolivia
Additional information:
34 VTL occur in 10 countries: Brazil, Indonesia, Zaire, Peru, Colombia, India, Bolivia, Papua New Guinea, Venezuela, Myanmar.
The leaders in terms of forest area per capita are: Guiana, Suriname, Gabon, Congo, etc.
Forest areas in Russia are declining, almost all forests have been eliminated in El Salvador, Jamaica and Haiti.
Animal resources, being also integral part biosphere, represent another vital important resource humanity, classified as renewable. On globe there are several million species of animals (there are much more of them than plants), some of them are domestic, others are commercial, etc. And together plants and animals form genetic fund (gene pool) planet, which also needs protection from impoverishment.
From 1600 to 1995, more than 600 species of animals have already disappeared on Earth, and another 35 thousand species (not counting invertebrates) are under threat of destruction. Especially strong pressure experiences animal world Europe, where many species of mammals and 30 to 50% of all bird species are on the verge of extinction. An example of the impoverishment of the gene pool in Africa and Asia is the catastrophically rapid decline in the elephant herd.
Preserving biological diversity and preventing “erosion” of the gene pool is a very important task.
Tasks and tests on the topic "Biological resources"
- 6 Tasks: 9 Tests: 1
Leading ideas: geographical environment - necessary condition life of society, development and distribution of the population and economy, while recently the influence of the resource factor on the level of economic development countries, but the importance of rational use of natural resources and environmental factor.
Basic concepts: geographical (environmental) environment, ore and non-metallic minerals, ore belts, mineral basins; structure of the world land fund, southern and northern forest belts, forest cover; hydropower potential; shelf, alternative energy sources; resource availability, natural resource potential(PRP), territorial combination of natural resources (TCNR), areas of new development, secondary resources; environmental pollution, environmental policy.
Skills and abilities: be able to characterize the natural resources of the country (region) according to plan; use different methods economic assessment natural resources; characterize the natural prerequisites for industrial development, Agriculture countries (regions) according to plan; give brief description placement of the main types of natural resources, distinguishing countries as “leaders” and “outsiders” in terms of provision with one or another type of natural resources; give examples of countries that are not rich natural resources, but have reached high level economic development and vice versa; give examples of rational and irrational use of resources.
IN scientific literature Often there is a description of the role of forests and forest vegetation as an integral part of the biosphere. It is usually noted that forests form the largest ecosystems on Earth in which most of organic matter planets. What do they have great importance for photosynthesis, for the normal course of processes of stabilizing the oxygen balance of the atmosphere, absorption carbon dioxide, as well as to preserve soil fertility and water purity. That they are the largest repositories of the gene pool of the biosphere, a habitat for large number plants and animals, an important source of wood, food, feed, technical, medicinal and other resources. In addition to all this, forests absorb noise and many air pollutants, thereby beneficially affecting the quality of the environment. natural environment, and indirectly on the mood of people who find positive emotions in communication with nature. In short, the economic, environmental, and aesthetic significance of forests is always highly valued.
For quantification world forest resources as an important component biological resources sushi, various indicators are used. The most important among them are indicators forest area, forest cover(proportion of forest area in the entire territory) and standing timber stock. However, when getting to know them, a rather significant difference in assessments attracts attention. If you try to compare the estimates of FAO, other international organizations and individual specialists in this field, then such a difference will be revealed quite easily. For example, in different sources global forest area is estimated at 51.2 billion hectares; 43.2; 39.6; 36.0; 34.4;
30.0 billion hectares. Accordingly, there are also large differences in the indicators of forest cover on the earth's land (37%, 32, 30, 27%, etc.), as well as in indicators of wood reserves (385 billion m 3, 350, 335 billion m 3, etc.) .
This discrepancy is explained by the fact that some of these estimates refer to different categories of forest area. The highest ones refer to the area of all lands forest fund, which, in addition to forest lands themselves, also include shrubs, open spaces, clearings, burnt areas, etc. The average ones correspond to a more strict approach to the definition of forest lands, the lower ones correspond to forested areas, i.e. directly occupied by forests, and the lowest ones to closed forests, which occupy no more than 2/3 of all forest areas and, perhaps, most accurately characterize the true forest cover of the territory. Sometimes statistics also take into account primary and secondary forests.
Table 28 gives an idea of regional differences in the distribution of the world's forest resources.
The following conclusions follow from the data presented in Table 28. Firstly, that Latin America occupies the leading place in the world in all important forest indicators. Secondly, the fact that the CIS falls into the “second echelon” according to these indicators, North America and Africa. Thirdly, that foreign Asia, characterized by high overall indicators, has - as one might expect - the lowest provision of forest resources per inhabitant. And fourthly, that for all the main indicators included in the table, large regions close the ranking foreign Europe and Australia and Oceania.
Table 28
DISTRIBUTION OF THE WORLD'S FOREST RESOURCES AMONG LARGE REGIONS
* Without CIS countries.
Along with the distribution of the world's forest resources across large regions of the world, their distribution across the main forest belts is also of great interest (Fig. 24). Figure 24 clearly shows the distribution coniferous forests cold zone (or coniferous boreal forests), stretching in a wide strip across the northern parts of Eurasia and North America. The belt extends to the south mixed forests temperate zone. Forests of dry areas are most characteristic of Africa (where they are represented by sparse forests and shrubs of the savannah zone), but are also found in North and South America and Australia. Equatorial rain forests grow in the belt with constant high temperatures and heavy rainfall north and south of the equator. Their main massifs are located in the Amazon and Congo river basins, as well as in South and Southeast Asia. Tropical rain forests in general are much worse preserved, and should be sought only in certain areas of Central and South America, Africa and South Asia. Finally, warm temperate rainforests occur in isolated, fairly large areas in North and South America, East Asia, and Australia.
Rice. 24. Schematic map of the world’s forests (according to I. S. Malakhov): 1 – coniferous forests of the cold zone; 2 – mixed forests temperate zone; 3 – forests of dry areas; 4 – equatorial rain forests; 5 – tropical rainforests; 6 – moist forests of the warm temperate zone
Figure 24 also provides the basis for a more generalized approach to identifying forest belts, which is more often used in educational literature. It consists of combining them into two main forest belts of the Earth– northern and southern, which are separated by a wide belt of arid territories.
Square northern forest belt– 2 billion hectares (including 1.6 billion hectares under a closed tree stand and 0.4 billion hectares under shrubs and open forests). The largest forest areas in this belt are located within Russia, Canada, and the USA. Coniferous trees occupy 67% of the total forest area, and deciduous trees - 33%. The diversity of species in the forests of the northern zone is not so great: for example, in foreign Europe there are approximately 250 species of trees and shrubs. Wood growth also occurs rather slowly. So, in coniferous forests In Russia, on average, 1.3 m 3 grows per 1 hectare per year, in Finland - 2.3 m 3, in the USA - 3.1 m 3. In the mixed forest zone this increase is noticeably greater.
Square southern forest belt– also approximately 2 billion hectares, but 97% of it consists of deciduous forests. At the same time, half of the entire forest area is occupied by tall-stemmed forest, and the rest is accounted for by low-density sparse forest, shrubs, and forest fallow. In the southern forest belt, the tree stand is much more diverse than in the northern: in all tropical forests per 1 hectare you can find more than 100 and even 200 various types trees. The average annual growth of wood per 1 hectare here is several times greater than in the forests of the northern zone. And the average stock of standing timber reaches 250 m 3 /ha, which is tens of times higher than the stock in some types of forests in the northern zone. Therefore, the total supply of wood in the forests of the southern belt is greater.
Naturally, countries with the largest forest areas should be sought within either the northern or southern forest belts (Fig. 25). These same belts also include countries with the highest forest cover: in the northern belt these are primarily Finland and Sweden, and in the southern belt - Suriname and Guyana in Latin America, Gabon and the Democratic Republic of the Congo in Africa, Papua New Guinea in Oceania.
Russia is the richest country in forest resources in the world. From Figure 25 it follows that this applies to both its forested and forested area (the latter is 22.1% of the world). The total timber reserves in Russian forests - 82 billion m3 - exceed the reserves of any large foreign region, with the exception of Latin America. This means that Russia accounts for more than 1/5 of the world's timber reserves, including almost 1/2 of the coniferous timber reserves. According to the corresponding per capita indicators (5.2 hectares and 560 m3), it is second only to Canada. However, Russia's forest resources are distributed very unevenly across its vast territory: almost 9/10 of the entire forested area is located in the taiga zone, especially within Eastern Siberia and the Far East.
Rice. 25. Top ten countries by forest area
26. Problems of deforestation
Deforestation(deforestation) is the loss of forest due to natural causes or as a result of economic activity person.
The process of anthropogenic deforestation actually began 10 thousand years ago, during the era of the Neolithic revolution and the emergence of agriculture and cattle breeding, and continues to this day. According to existing estimates, during the era of this revolution, 62 billion hectares (62 million km 2) of the earth's land were covered with forests, and taking into account shrubs and coppice - 75 billion hectares, or 56% of its entire surface. If we compare the second of these figures with the modern one, which was given above, it is not difficult to conclude that the forest cover of the land during the formation and development of human civilization has decreased by half. A spatial reflection of this process is shown in Figure 26.
This process took place in a certain and understandable geographical sequence. Thus, forests were first cleared in the areas of the ancient river civilizations of Western Asia, India, Eastern China, and in the era of ancient civilization - in the Mediterranean. In the Middle Ages, widespread deforestation began in foreign Europe, where until the 7th century. they occupied 70–80% of the entire territory, also on the Russian Plain. In the 17th–19th centuries, with the beginning of industrial revolutions, active industrial and urban development, as well as further development agriculture and livestock production, the process of deforestation has most affected Europe and North America, although it has also affected some other regions of the world. As a result, only in 1850–1980. The area of forests on Earth has decreased by another 15%.
Rice. 26. Change in the area covered by forest vegetation during the existence of civilization (according to K. S. Losev)
Deforestation continues at a rapid pace today: annually it occurs on an area of approximately 13 million hectares (these figures are comparable to the size of entire countries, for example Lebanon or Jamaica). The main reasons for deforestation remain the same. This is the need to increase agricultural land and areas intended for industrial, urban and transport development. it's the same constant growth needs for commercial and firewood (about 1/2 of all wood produced in the world is used for fuel). That is why the volume of timber harvesting is increasing all the time. Thus, in 1985, its global indicator was approximately 3 billion m 3, and by 2000 it increased to 4.5–5 billion m 3, which is comparable to the entire annual increase in wood in the world's forests. But we must also remember the damage that fires cause to forest vegetation, acid rain and other negative consequences of human activity.
However, it must be taken into account that the geographical distribution of deforestation in last decades has undergone significant changes. Its epicenter moved from the northern to the southern forest belt.
Economically developed countries, located within the northern forest belt, thanks to rational forestry management, the situation as a whole can be assessed as relatively prosperous. Forest areas in this belt have not only not been declining recently, but have even increased somewhat. This was a consequence of the implementation of a system of measures for the conservation and reproduction of forest resources. It includes not only control over the natural regeneration of forests, which is characteristic primarily of the taiga forests of North America and Eurasia, but also artificial afforestation, used in countries (primarily European) with previously cleared and unproductive forests. Nowadays, the volume of artificial reforestation in the northern forest belt already reaches 4 million hectares per year. In most countries of Europe and North America, as well as in China, timber growth exceeds annual cuttings.
This means that everything said above about increasing deforestation applies mainly to the southern forest belt, where this process takes on environmental disaster ugh. Moreover, the forests of this belt, as is well known, perform the most important function of the “lungs” of our planet and it is in them that more than half of all species of fauna and flora present on Earth are concentrated.
Rice. 27. Death of tropical forests in developing countries ah in 1980–1990 (according to "Rio-92")
The total area of tropical forests by the early 1980s. still amounted to about 2 billion hectares. In America they occupied 53% of the total area, in Asia - 36, in Africa - 32%. These forests, located within more than 70 countries, are usually divided into evergreen and semi-deciduous forests of the constantly humid tropics and deciduous and semi-deciduous forests and tree-shrub formations of the seasonally humid tropics. The category of tropical rainforests includes approximately 2/3 of all tropical forests in the world. Almost 3/4 of them are in just ten countries – Brazil, Indonesia, Democratic Republic Congo, Peru, Colombia, India, Bolivia, Papua – New Guinea, Venezuela and Myanmar.
However, then the deforestation of the southern belt accelerated: in UN documents, the speed of this process was first estimated at 11, and then began to be estimated at 15 million hectares per year (Fig. 27). Statistics show that only in the first half of the 1990s. V southern zone More than 65 million hectares of forests were cut down. According to some estimates, the total area of tropical forests has already decreased by 20–30% in recent decades. This process is most active in Central America, in the northern and southeastern parts South America, Western, Central and East Africa, in South and Southeast Asia (Fig. 28).
This geographical analysis can be brought to the level individual countries (Table 29). Following the top ten “record-breaking” countries, representing almost all the regions noted above, are Tanzania, Zambia, the Philippines, Colombia, Angola, Peru, Ecuador, Cambodia, Nicaragua, Vietnam, etc. As for the forest losses of individual countries, not expressed in absolute and in relative terms, the “leaders” here are Jamaica (7.8% of forests were cleared there per year), Bangladesh (4.1), Pakistan and Thailand (3.5), Philippines (3.4 %). But in many other countries of Central and South America, Africa, South and Southeast Asia, such losses amount to 1–3% per year. As a result, in El Salvador, Jamaica, and Haiti, almost all tropical forests have actually already been destroyed; in the Philippines, only 30% of primary forests have been preserved.
Rice. 28. Countries with the largest annual volumes of tropical forest clearing (according to T. Miller)
Can be called three main reasons leading to deforestation in the southern forest belt.
The first is to clear land for urban, transport and especially slash-and-burn agriculture, which still employs 20 million families in tropical forests and savannas. Slash-and-burn agriculture is believed to be responsible for the destruction of 75% of the forest area in Africa, 50% of the forests in Asia and 35% of the forests in Latin America.
Table 29
TOP TEN COUNTRIES BY AVERAGE ANNUAL FOREST CLEARANCE
The second reason is the use of wood as fuel. According to the UN, 70% of the population of developing countries use firewood for heating their homes and cooking. In many countries Tropical Africa, in Nepal and Haiti their share in the fuel used reaches 90%. The rise in oil prices on the world market in the 1970s. led to the fact that forests began to be cut down (primarily in Africa and South Asia) not only in the near but also in the distant surroundings of cities. In 1980, approximately 1.2 billion people in developing countries lived in areas experiencing firewood shortages, and by 2005 this number had risen to 2.4 billion.
The third reason is the increasing export of tropical wood from Asia, Africa and Latin America to Japan, Western Europe and the USA, and its use for the needs of the pulp and paper industry.
The poor, and especially the poorest developing countries, are forced to do this in order to at least slightly improve their balance of payments, burdened by debts to the rich countries of the North. Many believe that they cannot be blamed for such a policy. For example, at the opening of the IX Forestry Congress held in Paris in 1991, then-President of France François Mitterrand said: “What right do we have to reproach the population of tropical regions, for example, for contributing to the destruction of forests when they are forced to do so in order to just get by."
To prevent the complete destruction of tropical forests already in the 21st century. Urgent and effective measures are needed. Among the possible ways of reproducing forest areas in the southern zone, the greatest effect, perhaps, can be achieved by creating forest plantations specifically designed for growing highly productive and fast-growing tree species, such as eucalyptus. The existing experience in creating such plantations shows that they make it possible to grow 10 times more valuable wood than, say, European forests. At the end of the 1990s. Such plantations worldwide already occupied 4.5 million hectares, of which 2 million hectares were in Brazil.
At the World Conference on Environment and Development in Rio de Janeiro in 1992, the Statement of Principles on Forests was adopted as a special document.
Many of the problems listed above are also relevant for Russia, despite its wealth of forest resources. With a formal approach to this issue, there is no reason for any concern. Indeed, the country's estimated logging area is 540 million m3, but approximately 100 million m3 is actually cut down. However, these are averages and do not take into account differences between European part countries where the estimated logging area is often exceeded, and the Asian part where it is underutilized. Significant mortality must also be taken into account forest plantations, primarily due to forest fires(in 2006 – 15 million hectares). Therefore, Russia is taking measures for rational forest management and reproduction of forest resources. Now the area under forests is not decreasing, but growing.
(97% composed of broadleaf forests - mainly rainforests and tropical forests of developing countries).
Over the past 200 years alone, the area of forests in the world has decreased by 2 times. Destruction of forests at such a rate will have catastrophic consequences for the whole world, as the supply of oxygen in the world is reduced, ““ increases, and the climate on the planet is changing.
The largest area of forests has been preserved in and, the smallest -. However, the sizes of the continents are not the same, so it is important to take into account the forest cover indicator (the ratio of forested area to the total area of the region), as well as the size of wood reserves and the area of forested surface per 1 inhabitant.
The reduction of forest cover is becoming a very serious global problem. The forests of the northern forest belt in now economically developed countries were subject to intensive destruction in the past, but then the forest cover was restored to a greater extent (afforestation). In some countries with government conservation programs, timber growth has begun to exceed the volume of timber harvested. And the main reason for the loss of forests and the decline in its quality in developed countries in recent decades has been acid rain (from pollution air environment). According to experts, the total area of affected forests is about 30 million hectares.
For many centuries, the reduction of forest area on the planet has practically not impeded the progress of mankind. However, recently this process has begun to have a negative impact on the economic and ecological condition many countries. And although about 30% of the land is still covered with wood, forest protection and work are necessary for the continued existence of humanity.
The scientific literature often describes the role of forests and forest vegetation as an integral part of the biosphere. It is usually noted that forests form the largest ecosystems on Earth, in which most of the planet’s organic matter accumulates. That they are of great importance for photosynthesis, for the normal course of processes of stabilizing the oxygen balance of the atmosphere, the absorption of carbon dioxide, as well as for maintaining soil fertility and water purity. That they are the largest repositories of the gene pool of the biosphere, a habitat for a large number of plants and animals, an important source of wood, food, feed, technical, medicinal and other resources. In addition to all this, forests absorb noise and many air pollutants, thereby favorably influencing the quality of the natural environment, and indirectly the mood of people who find positive emotions in communication with nature. In short, the economic, environmental, and aesthetic significance of forests is always highly valued.
Various indicators are used to quantify the world's forest resources as an important component of terrestrial biological resources. The most important among them are indicators forest area, forest cover(proportion of forest area in the entire territory) and standing timber stock. However, when getting to know them, a rather significant difference in assessments attracts attention. If you try to compare the estimates of FAO, other international organizations and individual specialists in this field, then such a difference will be revealed quite easily. For example, various sources estimate the global forest area at 51.2 billion hectares; 43.2; 39.6; 36.0; 34.4;
30.0 billion hectares. Accordingly, there are also large differences in the indicators of forest cover on the earth's land (37%, 32, 30, 27%, etc.), as well as in indicators of wood reserves (385 billion m 3, 350, 335 billion m 3, etc.) .
This discrepancy is explained by the fact that some of these estimates refer to different categories of forest area. The highest of them refer to the area of all forest land, which, in addition to forest land itself, also includes shrubs, open areas, clearings, burnt areas, etc. The average ones correspond to a more strict approach to the definition of forest land, the lower ones - to forested land, i.e. . areas directly occupied by forests, and the lowest - to closed forests, which occupy no more than 2/3 of all forest areas and, perhaps, most accurately characterize the true forest cover of the territory. Sometimes statistics also take into account primary and secondary forests.
Table 28 gives an idea of regional differences in the distribution of the world's forest resources.
The following conclusions follow from the data presented in Table 28. Firstly, that Latin America occupies the leading place in the world in all important forest indicators. Secondly, that the CIS, North America and Africa fall into the “second echelon” according to these indicators. Thirdly, that foreign Asia, which is distinguished by high overall indicators, has - as one might expect - the lowest provision of forest resources per capita. And fourthly, that for all the main indicators included in the table, foreign Europe and Australia with Oceania close the ranking of large regions.
Table 28
DISTRIBUTION OF THE WORLD'S FOREST RESOURCES AMONG LARGE REGIONS
* Without CIS countries.
Along with the distribution of the world's forest resources across large regions of the world, their distribution across the main forest belts is also of great interest (Fig. 24). Figure 24 clearly shows the distribution of coniferous forests of the cold zone (or coniferous boreal forests), stretching in a wide strip across the northern parts of Eurasia and North America. To the south lies a belt of mixed temperate forests. Forests of dry areas are most characteristic of Africa (where they are represented by sparse forests and shrubs of the savannah zone), but are also found in North and South America and Australia. Equatorial rain forests grow in a belt of consistently high temperatures and heavy rainfall north and south of the equator. Their main massifs are located in the Amazon and Congo river basins, as well as in South and Southeast Asia. Tropical rain forests are generally much less well preserved and should be sought only in isolated areas of Central and South America, Africa and South Asia. Finally, warm temperate rainforests occur in isolated, fairly large areas in North and South America, East Asia, and Australia.
Rice. 24. Schematic map of the world’s forests (according to I. S. Malakhov): 1 – coniferous forests of the cold zone; 2 – mixed forests of the temperate zone; 3 – forests of dry areas; 4 – equatorial rain forests; 5 – tropical rainforests; 6 – moist forests of the warm temperate zone
Figure 24 also provides the basis for a more generalized approach to identifying forest belts, which is more often used in educational literature. It consists of combining them into two main forest belts of the Earth– northern and southern, which are separated by a wide belt of arid territories.
Square northern forest belt– 2 billion hectares (including 1.6 billion hectares under a closed tree stand and 0.4 billion hectares under shrubs and open forests). The largest forest areas in this belt are located within Russia, Canada, and the USA. Coniferous trees occupy 67% of the total forest area, and deciduous trees - 33%. The diversity of species in the forests of the northern zone is not so great: for example, in foreign Europe there are approximately 250 species of trees and shrubs. Wood growth also occurs rather slowly. Thus, in the coniferous forests of Russia, on average, 1.3 m 3 grows per 1 hectare per year, in Finland - 2.3 m 3, in the USA - 3.1 m 3. In the mixed forest zone this increase is noticeably greater.
Square southern forest belt– also approximately 2 billion hectares, but 97% of it consists of broad-leaved forests. At the same time, half of the entire forest area is occupied by tall-stemmed forest, and the rest is accounted for by low-density sparse forest, shrubs, and forest fallow. In the southern forest belt, the tree stand is much more diverse than in the northern one: in all tropical forests per 1 hectare you can find more than 100 and even 200 different species of trees. The average annual growth of wood per 1 hectare here is several times greater than in the forests of the northern zone. And the average stock of standing timber reaches 250 m 3 /ha, which is tens of times higher than the stock in some types of forests in the northern zone. Therefore, the total supply of wood in the forests of the southern belt is greater.
Naturally, countries with the largest forest areas should be sought within either the northern or southern forest belts (Fig. 25). These same belts also include countries with the highest forest cover: in the northern belt these are primarily Finland and Sweden, and in the southern belt - Suriname and Guyana in Latin America, Gabon and the Democratic Republic of the Congo in Africa, Papua New Guinea in Oceania.
Russia is the richest country in forest resources in the world. From Figure 25 it follows that this applies to both its forested and forested area (the latter is 22.1% of the world). The total timber reserves in Russian forests—82 billion m3—exceed those of any major foreign region, with the exception of Latin America. This means that Russia accounts for more than 1/5 of the world's timber reserves, including almost 1/2 of the coniferous timber reserves. According to the corresponding per capita indicators (5.2 hectares and 560 m3), it is second only to Canada. However, Russia's forest resources are distributed very unevenly across its vast territory: almost 9/10 of the entire forested area is located in the taiga zone, especially within Eastern Siberia and the Far East.
Rice.25. Top ten countries by forest area
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