Soil is a special natural formation that provides the growth of trees, crops and other plants. It is difficult to imagine life without our fertile soils. But how does modern man relate to soils? Today, human pollution of the soil has reached colossal proportions, so the soils of our planet are in dire need of protection and protection.
Soil - what is it?
Protection of soils from pollution is impossible without a clear understanding of what soil is and how it is formed. Let's consider this question in more detail.
Soil (or soil) is a special natural formation, an indispensable component of any ecosystem. It is formed in the upper layer of the parent rock, under the influence of the sun, water, and vegetation. The soil is a kind of bridge, a link that connects the biotic and abiotic components of the landscape.
The main processes that form soil are weathering and the vital activity of livingorganisms. As a result of mechanical weathering processes, the parent rock is destroyed and gradually crushed, and living organisms fill this inanimate mass with organic substances.
Human pollution of the soil is one of the main problems of modern ecology and nature management, which became especially acute in the second half of the twentieth century.
Soil structure
Any soil consists of 4 main components. This is:
- rock (base soil, about 50% of the total mass);
- water (about 25%);
- air (about 15%);
- organic matter (humus, up to 10%).
Depending on the ratio of these components in the soil, the following types of soils are distinguished:
- stony;
- clay;
- sandy;
- humic;
- saline.
The key property of the soil, which distinguishes it from any other component of the landscape, is its fertility. This is a unique property that satisfies the plants in the necessary nutrients, moisture and air. Thus, the soil ensures the biological productivity of all vegetation and crop yields. This is why soil and water pollution is such a pressing problem on the planet.
Soil cover surveys
Soil research is carried out by a special science - soil science, the founder of which is Vasily Dokuchaev, a world-famous scientist. It was he who, at the end of the 19th century, was the first to note that soils spread alongthe earth's surface is quite natural (latitudinal zonality of soils), and also named clear morphological features of the soil.
B. Dokuchaev considered the soil as an integral and independent natural formation, which none of the scientists had done before him. The most famous work of the scientist - "Russian Chernozem" of 1883 - is a reference book for all modern soil scientists. V. Dokuchaev conducted a thorough study of the soils of the steppe zone of modern Russia and Ukraine, the results of which formed the basis of the book. In it, the author singled out the main factors of soil formation: parent rock, relief, climate, age and flora. The scientist gives a very interesting definition of the concept: "soil is a function of the parent rock, climate and organisms, multiplied by time."
After Dokuchaev, other well-known scientists were also actively involved in the study of soils. Among them: P. Kostychev, N. Sibirtsev, K. Glinka and others.
The importance and role of soil in human life
The phrase "earth-nurse", which we hear very often, is not symbolic or metaphorical. It really is. This is the main source of food for mankind, which, one way or another, provides about 95% of all food. The total area of all land resources of our planet today is 129 million km22 land area, of which 10% is arable land, and another 25% is hayfields and pastures.
Soils began to be studied only in the 19th century, but people knew about their wonderful property - fertility,from the most ancient times. It is the soil that owes its existence to all plant and animal organisms on Earth, including humans. It is no coincidence that the most densely populated areas of the planet are the areas with the most fertile soils.
Soil is the main resource of agricultural production. Many conventions and declarations adopted at the international level call for a rational and careful treatment of the soil. And this is obvious, because the total pollution of lands and soils threatens the existence of all mankind on the planet.
Soil cover is the most important element of the geographic shell of the Earth, responsible for all processes in the biosphere. The soil accumulates a huge amount of organic matter and energy, thus acting as a giant biological filter. This is a key link in the biosphere, the destruction of which will disrupt its entire functional structure.
In the 21st century, the load on the soil cover has increased several times, and the problem of soil pollution is becoming a paramount and global one. It is worth noting that the solution to this problem depends on the coordination of actions of all states of the world.
Land and soil pollution
Soil pollution is the process of degradation of the soil cover, which significantly increases the content of chemicals in it. Indicators of this process are living organisms, in particular, plants, which are the first to suffer from a violation of the natural composition of the soil. At the same time, the reaction of plants depends on the level of their sensitivity to such changes.
ShouldIt should be noted that our state provides for criminal liability for human pollution of land. In particular, Article 254 of the Criminal Code of the Russian Federation sounds like "Spoilage of the earth".
Typology of soil pollutants
The main soil pollution began in the twentieth century with the rapid development of the industrial complex. Soil pollution is understood as the introduction into the soil of components atypical for it - the so-called "pollutants". They can be in any state of aggregation - liquid, solid, gaseous or complex.
All soil pollutants can be divided into 4 groups:
- organic (pesticides, insecticides, herbicides, aromatic hydrocarbons, chlorine compounds, phenols, organic acids, petroleum products, gasoline, varnishes and paints);
- inorganic (heavy metals, asbestos, cyanides, alkalis, inorganic acids and others);
- radioactive;
- biological (bacteria, pathogens, algae, etc.).
Thus, the main soil pollution is carried out with the help of these and some other pollutants. The increased content of these substances in the soil can lead to negative and irreversible consequences.
Sources of land pollution
Today, you can name a large number of such sources. And their number only increases every year.
Let's list the main sources of soil pollution:
- Residential buildings and utilities. This is the main sourceland pollution in cities. In this case, human contamination of the soil occurs through household waste, food debris, construction debris and household items (old furniture, clothes, etc.). In large cities, the question "where to put the garbage?" turns into a real tragedy for the city authorities. Therefore, on the outskirts of cities, huge kilometer-long landfills grow up, where all household garbage is dumped. In the developed countries of the West, the practice of waste processing at special installations and factories has long been introduced. And this is where a lot of money is made. In our country, such cases, alas, are rare so far.
- Factories and plants. In this group, the main sources of soil pollution are the chemical, mining and engineering industries. Cyanides, arsenic, styrene, benzene, polymer clots, soot - all these terrible substances enter the soil in the area of large industrial enterprises. A big problem now is also the problem of recycling car tires, which are the cause of large fires that are very difficult to extinguish.
- Transport complex. The sources of land pollution in this case are lead, hydrocarbons, soot, and nitrogen oxides. All these substances are released during the operation of internal combustion engines, then they settle on the surface of the earth and are absorbed by plants. Thus, they also enter the soil cover. At the same time, the degree of soil pollution will be as high as possible along major highways and near road junctions.
- Agro-industrial complex. Receiving food from the earth, we at the same time poison it, as ifIt didn't sound paradoxical. Human pollution of the soil here occurs through the introduction of fertilizers and chemicals into the soil. This is how substances that are terrible for him get into the soil - mercury, pesticides, lead and cadmium. In addition, excess chemicals can be washed from fields by rainfall into permanent streams and groundwater.
- Radioactive waste. Soil contamination by nuclear industry waste carries a very great danger. Few people know that during nuclear reactions at nuclear power plants, about 98-99% of the fuel goes to waste. These are the fission products of uranium - cesium, plutonium, strontium and other elements that are extremely dangerous. A very big problem for our country is the disposal of this radioactive waste. About 200,000 cubic meters of nuclear waste is generated every year in the world.
Main types of pollution
Soil pollution can be natural (for example, during volcanic eruptions), or anthropogenic (technogenic), when pollution occurs through human fault. In the latter case, substances and products that are not characteristic of the natural environment and adversely affect ecosystems and natural complexes get into the soil.
The process of classifying the types of soil pollution is very complex, different sources give different classifications. But still, the main types of soil pollution can be represented as follows.
Household soil pollution is soil pollution with garbage, waste and emissions. This group includes pollutants of a different nature and in a different state of aggregation. They arecan be either liquid or solid. In general, this type of pollution is not too dangerous for the soil, however, excessive accumulation of household waste clogs the area and prevents the normal growth of plants. The problem of domestic soil pollution is most acute in megalopolises and large cities, as well as in settlements with an inadequate garbage collection system.
Chemical pollution of soils is, first of all, pollution by heavy metals, as well as pesticides. This type of pollution already poses a great danger to humans. After all, heavy metals have the ability to accumulate in a living organism. Soils are contaminated with heavy metals such as lead, cadmium, chromium, copper, nickel, mercury, arsenic and manganese. A major soil pollutant is gasoline, which contains a very toxic substance - tetraethyl lead.
Pesticides are also very dangerous substances for the soil. The main source of pesticides is modern agriculture, which actively uses these chemicals in the fight against beetles and pests. Therefore, pesticides accumulate in soils in large quantities. For animals and humans, they are no less dangerous than heavy metals. Thus, the highly toxic and very stable drug DDT was banned. It is able not to decompose in the soil for decades, scientists have found traces of it even in Antarctica!
Pesticides are very detrimental to soil microflora: bacteria and fungi.
Radioactive contamination of soils is the contamination of soils with waste from nuclear power plants. Radioactive substances are extremely dangerous because they are easilyenter the food chain of living organisms. The most dangerous radioactive isotope is considered to be strontium-90, which is characterized by a high yield during nuclear fission (up to 8%), as well as a long (28 years) half-life. In addition, it is very mobile in the soil and is able to be deposited in the bone tissue of humans and various living organisms. Other hazardous radionuclides include cesium-137, cerium-144, chlorine-36.
Volcanic soil pollution - this type of pollution belongs to the group of natural. It consists in the ingress of toxic substances, soot and combustion products into the soil, which occurs as a result of volcanic eruptions. This is a very rare type of soil pollution, which is typical only for certain small areas.
Mycotoxic pollution of soils is also not technogenic and has a natural origin. The source of pollution here are some types of fungi that emit hazardous substances - mycotoxins. It is worth noting that these substances pose the same great danger to living organisms as all the others listed above.
Soil erosion
Erosion has been and remains a major problem for the preservation of the fertile soil layer. Every year it "eats" large areas of fertile soil, while the rate of natural restoration of the soil cover is much lower than the rate of erosion processes. Scientists have already thoroughly studied the features of these processes and found measures to combat them.
Erosion can be:
- water
- wind
Obviously,in the first case, flowing water is the leading erosion factor, and in the second, wind.
Water erosion is more common and dangerous. It begins with the appearance on the earth's surface of a small, barely noticeable ravine, but after each heavy rain, this gully will expand and increase in size until it turns into a real moat. During the summer period alone, on an absolutely flat surface, a moat with a depth of 1-2 meters can appear! The next stage of water erosion is the formation of a ravine. This landform is characterized by great depth and a branched structure. Ravines catastrophically destroy fields, meadows and pastures. If the ravine is not fought, sooner or later it will turn into a beam.
Water erosion processes are more active in the steppe region with rugged terrain, where there is very little vegetation.
Wind erosion is caused by storms and dry winds, which can blow up to 20 centimeters of the upper (most fertile) soil ball. The wind carries soil particles over long distances, forming sediments up to 1-2 meters high in certain places. Most often they form along plantings and forest belts.
Soil pollution assessment
To carry out a set of measures to protect the soil cover, an adequate assessment of soil pollution is very important. It is calculated by complex mathematical calculations, after a complex of detailed chemical and environmental studies. The assessment is presented by a complex indicator of pollution Zc.
Evaluation of soil pollution is carried out taking into account several important factors:
- specificity of pollution sources;
- complex of chemical elements - soil pollutants;
- priority of pollutants, according to the list of MPC substances;
- nature and conditions of land use.
Researchers identify several levels of soil pollution, namely:
- Valid (Zwith less than 16).
- Moderately dangerous (Zfrom 16 to 38).
- Dangerous (Zc from 38 to 128).
- Extremely dangerous (Zwith over 128).
Soil protection
Depending on the source of pollution and the intensity of its influence, special measures have been developed to protect the soil cover. These measures include:
- Legislative and administrative (adoption of relevant laws in the field of soil protection, and control over their implementation).
- Technological (creation of waste-free production systems).
- Sanitation (collection, disinfection and disposal of waste and soil pollutants).
- Scientific (development of new technologies for wastewater treatment plants, assessment and monitoring of soil conditions).
- Forest reclamation and anti-erosion (these are measures for planting special shelter belts along the fields, the construction of hydraulic structures and the correct planting of crops).
Conclusion
The soils of Russia are a colossal we alth, thanks to which we have food, and production is provided with the necessary raw materials. Primingformed over many centuries. That is why the protection of soils from pollution is the most important task of the state.
Today, there are a large number of sources of soil pollution: these are transport, industry, cities, utilities, nuclear power plants, agriculture. The common task of scientists, government authorities and public figures is to protect soils from the harmful effects of all these factors, or at least minimize their harmful effects on soils.
