The ecological and economic role of forest ecosystems in resource conservation

Forests perform a vital ecological function. Forested watersheds act as giant sponges, absorbing, storing, and gradually releasing water, feeding streams, rivers, and groundwater horizons. Forests regulate runoff from mountains to lowland ploughed and urban lands, help prevent soil erosion and flooding, and control the amount of sediment entering rivers, lakes, and reservoirs with runoff.

Forests play an important role in global carbon and oxygen cycles. Through the process of photosynthesis trees clean the air by absorbing carbon dioxide and releasing oxygen. When trees are cut down and burned, the carbon stored within them enters the atmosphere as carbon dioxide. Deforestation also leads to the oxidation and release into the air of carbon accumulated in the soil under the trees. Thus, large-scale deforestation makes a significant contribution to the greenhouse effect.

Forests serve as a natural habitat for a greater number of wild plant and animal species than any other ecosystem. This makes them the largest reservoir of biological diversity on our planet. In addition, forests absorb noise and many air pollutants, and have a beneficial effect on people's mood, meeting their need for solitude and beauty.

According to an estimate, over a 50-year lifespan, an average tree in a tropical forest provides ecological income from oxygen production, air pollution reduction, erosion control and soil fertility, water regime regulation, wildlife habitat provision, and protein production valued at 196,250 dollars. Sold as timber, it will bring only about 590 dollars.

Tropical forests are the source of half of all the world's hardwood production. Food products obtained in tropical forests include coffee, cocoa, spices, nuts, and fruits. Raw materials for a quarter of all the medicines we use are obtained from plants growing in tropical forests. Aspirin is produced based on a substance extracted from the leaves of tropical willow trees. About 70% of promising anti-cancer drugs can be derived from plants of tropical rainforests.

The cedar is called a miracle of Siberia, a pearl of the taiga, and a bread tree. Its nut kernel contains up to 60% fat, 20% protein, 12% starch, 4% fiber, as well as a whole complex of vitamins that improve blood composition and have a beneficial effect on skin tissue. In terms of caloric value, cedar oil is not inferior to chicken eggs, and it is a good remedy for treating lung and kidney diseases.

Among the main reasons for deforestation, the following should be highlighted: • development of new territories for agriculture; • obtaining timber for construction, woodworking, and the paper industry; • obtaining fuel for cooking and heating; • forest fires.

Developed countries experienced mass deforestation even before and during the Industrial Revolution, which led to severe consequences for them, such as a decrease in the soil fertility of many lands. However, industrialized countries have generally realized this problem and are currently restoring forests at a rate at least equal to the rate of their cutting.

In developing countries, the era of modern energy has not yet arrived for two-thirds of the population (about 2.5 billion people). Firewood is still needed for heating and cooking. Even in cities, many use charcoal produced in rural areas by cutting and burning wood. Approximately 60% of these people cut down forests faster than they grow. In some countries, logging proceeds five times faster than reforestation.

Since the beginning of this century, the area under African forests has shrunk by almost half, and in some countries by 5 to 10 times. For instance, in Ethiopia at the beginning of the century, forests covered 40% of the territory. Now, only 3.5% remains forested. In India, 40 years ago, forests occupied 22% of the territory; now they account for barely 10%.

Siberia's forests are disappearing at an alarming rate. Here, more than half a million hectares of forests are cut down annually, while new planting is carried out on only one-third of the logged areas. Scientists are recording changes in the Siberian landscape. In most cases, swamping of the area begins at the site of logging. Since pine and even cedar, the most valuable forests, are cut down first, the impoverishment of the forest cover is observed everywhere. In 1988, the Tomsk taiga burned 500 times. Forest fires in Siberia are facilitated by the maintenance personnel of oil pipelines who burn off oil: in the spring of 1989, due to the fault of workers of the Alexandrovskoye oil pipeline department, 25 hectares of cedar taiga burned down.

Thus, under human pressure, forests are retreating on all continents, in practically every country, but the most massive destruction of forest cover is occurring in the tropical belt.

Forests save the planet's pastures, which support about 3 billion heads of livestock, from desertification.

Every type of pasture has its own carrying capacity - the maximum number of herbivores that a given area can provide with food. The capacity depends on the season, the condition of the pasture, its previous grazing use, climatic conditions, soil type, the species of grazing animals, and the grazing period.

Light to moderate grazing is necessary for the normal functioning of pasture ecosystems. It maintains the water and nutrient cycle, which is essential for the normal growth of grasses and the development of root systems, as well as for curbing soil erosion and accumulating organic matter in the soil.

Overgrazing is observed when too many grazing animals feed on a pasture for a long time and exceed its capacity. Large populations of wild herbivores can cause overgrazing during prolonged drought periods. However, overgrazing is primarily caused by prolonged grazing of an excessive number of livestock on a specific area.

Severe overgrazing turns a continuous grass cover into isolated sod patches and increases the soil's susceptibility to erosion. Sometimes overgrazing is so severe that all vegetation disappears and barren deserts are formed, which are particularly prone to erosion. Overgrazing combined with prolonged drought can turn a potentially productive pasture into a desert.

All-terrain vehicles also damage or destroy the vegetation cover of pasture lands.

Consequences of human impact on pasture lands

Undergrazing can also worsen the condition of a pasture as a source of food for livestock and many wild herbivores. In this case, most of the leaves and stems remain undamaged, which stifles grass growth and shifts the process of succession from grasses to woody plants and forbs.

Undergrazing, similar to overgrazing, leads to a disruption of nutrient and water cycles, and increases soil erosion and degradation.

Pasture condition analysis and methods of sustainable livestock farming

Two-thirds of US pastures are in fair to poor condition. In Iraq, the number of livestock exceeds the carrying capacity of pastures fourfold, and in Syria - threefold. In Russia, too, in some regions, the pressure on nature exceeds the available natural resource potential. Kalmykia is an example. Previously, there were never more than 890,000 sheep here, each yielding 25 kg of meat. Now there are at least 4 million sheep. In total, they produce as much as the previous 890,000, but of lower quality.

It turns out that pasture productivity is higher when used by wild animals. For instance, 150 kg of wild animal meat was obtained from 1 hectare of African savanna, whereas fattening domestic animals on a similar area yielded 6 times less. Humans simply have not yet learned how to integrate their livestock farming into nature without causing harm.

Controlling the distribution of grazing animals across the pasture is the best way to prevent overgrazing and undergrazing. To this end, livestock farmers can:

• build fences to protect degraded pastures;
• rotate livestock from one pasture to another;
• provide supplemental feeding in specific areas;
• place water and salt in key locations.