The silent killer threatens to turn Vojvodina into a desert
If the attitude towards the land is not improved in the coming period, Vojvodina could turn from the "granary of Europe" into a desert, experts warn. In the last fifty years, the level of organic matter has dropped drastically. In the past, as many as three-quarters of the arable land in the north of the country had more than 5 percent humus - today, only one percent of the fields have such a composition. Experts call this degradation the silent killer of soil.
The silent killer of the soil is rampant in Serbia. If not stopped, food production could be questionable in the coming decades, experts point out.
"There are a lot of soil degradation processes. Floods and erosion are obvious. And then, in a short period of time, action is taken to stop the processes or remediate the consequences," says Dr. Jovica Vasin, pedologist at the Soil and Agroecology Laboratory of the Institute for Agriculture and Vegetables in Novi Sad, which is one of the four institutes of national importance for the Republic of Serbia.
"However, the process of soil destruction that is the most important and the most pronounced is the loss of organic matter. We call it the silent killer of the soil. Silent, because it lasts for a very long time. The killer is because the content of organic matter in arable land and in central Serbia, especially in Vojvodina, has already reached to such a low level that it endangers agricultural production," explains our interlocutor.
In the past, most of Vojvodina's land was rich in humus.
"About 75 percent of the surface of Vojvodina is covered by two types of soil, chernozem and rite chert, which in the second half of the last century had an organic matter content above five percent. Today, this humus content is present on only one percent of the surface. The problem is in rapidly decreasing livestock fund - for the past three decades at a rate of two to three percent per year. This is the answer to the question why most fields in Serbia do not use manure as an organic fertilizer, but mineral fertilizers," says Branislav Gulan, an agro-economic analyst.
"The negative effects of the reduction of humus are already visible, because despite the implementation of complete agrotechnical measures, the yields are decreasing," adds our interlocutor.
Without manure, it is not worth watering the fields
Intensive agriculture cannot be imagined without irrigation. Existing and new irrigation systems are mostly discussed in summer and in dry years. However, even if we water far more superficially than we do, the question is what kind of results we would achieve in the long term with this kind of relationship we have with the land.
"It is good that new irrigation systems are being built. According to the data of the Republic Institute of Statistics, water now reaches only 1.5 percent of arable land in Serbia, while in the world as much as 17 percent of the land is irrigated. However, if in the next half century we water fertile arable land, whose soil quality is constantly declining, and if there is no natural fertilizer, we will create a desert from the grain of the land, in terms of yields," Gulan warns.
"The best confirmation of such a situation is that the value of production has been stagnant for decades at the level of between four and five billion dollars per year. Analysts have calculated that agriculture in Serbia for the last three and a half decades has had an annual growth rate of only 0.45 percent. According to the last valid Development Strategy of agriculture, which was adopted by the Government of Serbia at the end of July 2014, and which is valid for another year, the growth should have been 9.1 or, in a milder version, 6.1 percent. I remind you that the strategy should have been adopted by the Serbian Parliament, but after pointing out unreality, the document was never sent to the parliament," added Gulan.
The level of humus in the fields is extremely low
The process of soil degradation, which involves the reduction of organic matter, takes a very long time. Ever since the "green revolution" of the seventies of the last century, when the use of mineral fertilizers increased.
"At that time, it was thought that it would be enough to feed the plants. However,
due to the reduced use of organic fertilizers and some other bad practices in agriculture, such as, for example, burning crop residues,
removing crop residues for energy production from areas that are not adequate for that, we have come to a situation where the dominant content of humus in the soil in Vojvodina is around three, or even below three percent," says Vasin.
"In professional practice, this is considered to indicate when plots should be fertilized with increased amounts of organic fertilizers, because the soil is so degraded that it requires a measure of repair," adds our interlocutor.
In order to achieve good yields on some land, it is first necessary to know what its quality is.
"The recommendation is to perform a soil analysis before starting agricultural production on a certain plot. Only based on the results of testing the basic parameters of soil fertility such as pH value, calcium carbonate content, organic matter-humus content, easily accessible phosphorus and potassium content can be obtained guidelines for the rational application of fertilizers, mineral and organic forms", explains Radmila Pivić, scientific advisor at the Soil Institute.
Measures to improve soil quality
The process of enriching the soil with humus takes time. As long as the degradation lasted, experts say, it is necessary to improve the situation with the land. Because we need to stop bad practices as soon as possible and start processes that are beneficial for the soil.
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It is essential to increase the application of manure. However, due to the reduced livestock stock, we do not have enough manure. That is why we must apply organic fertilizers that could be a substitute for manure. For example, composting different organic materials from both urban waste and waste that is a by-product of the food industry," says Vasin.
"Harvest residues must not be burned, it is preferable to plow them and add them to the soil. Also, during the construction of a bioenergy plant, one should take into account where the raw material base for such a plant is, i.e. from which areas the harvest residues will be removed. These can only be those areas which have enough organic matter in them. No areas where we have a problem with humus, which, unfortunately, have become dominant," adds our interlocutor.
Experts point out that land should be used rationally.
"For successful agricultural production, it is necessary to respect the correct crop rotation, combine crops, grow intercrops and winter cover crops, implement green fertilization, mulching. There are also measures that foresee a reduction of nutrient losses in the soil by at least 50 percent and a reduction in the use of fertilizers by at least 20 percent until 2030, while ensuring that the fertility of the soil does not decrease," says Pivić.
"One example of the new green model is carbon sequestration in agriculture and encouraging practices that store carbon dioxide in the organic matter of the soil. This can be achieved by applying high-quality composted fertilizers, introducing wider crop rotations, cover crops, green manures and, if necessary, melioration measures - calcification and by plastering the soil", adds our interlocutor.
The state should encourage farmers to increase the level of humus in the soil
According to experts, for certain measures that increase the percentage of humus in the soil, it is necessary for the state to help farmers with incentives.
"Let's say sideration or green manure is a measure that can significantly improve the situation. This implies that plants that are intended for plowing are grown. The complete, underground and above-ground mass is used to plow into the soil in the period when the vegetation is the largest. This increases the content humus and other soil properties related to organic matter," explains Vasin.
"The problem to such an extent is that the farmer does not benefit directly from that one vegetation. He benefits from it, but it is long-term. In the short term, he does not have a marketable product that he can sell, and he has investment costs in fuel and seeds. That is why state subsidies are needed to help farmers who work as a sideration measure", specified our interlocutor.
Humus is not only important for agriculture
Humus greatly affects the water, air and heat regime of the soil.
"Soil that has enough organic matter retains moisture for a longer period of time than soil with a low content of organic matter. This provides plants with additional moisture and those on such soil better tolerate drought. This is very important in today's conditions," says Vasin.
"Usually we say that organic matter for the soil is the same as honey for humans. It is a small percentage in the total volume of the soil, only a few percent, but from the aspect of importance and influence on biological activity and on the yield itself, which is important to the farmer, it is very significant ", explains our interlocutor.
In addition to agriculture, humus is also important because it prevents harmful processes in nature.
"Many believe that the solution to global warming is precisely to increase the content of organic matter, i.e. organic carbon in the soil. It is thus bound and does not go into the atmosphere, greenhouse gases that cause warming are not created. The question of the content of organic matter is not important only for agriculture or a local community, but it has global importance for today's civilization," Vasin points out.
The solution to this serious problem should certainly be sought in the recovery of animal husbandry, which in Serbia participates in the total agricultural production with less than 30 percent, while in developed countries it is more than 60 percent.
In order to maintain good soil quality, it would be optimal, experts say, to add 40 tons of manure per hectare every fourth year. For something like that, Serbia needs to have
two conditional heads of cattle per hectare, and we don't have even ten times less.
It is interesting that the six largest owners of agricultural land in Serbia have about 110,000 hectares of arable land. According to the previous calculation, only they should have 220,000 bulls. And Serbia now does not have enough cattle for a loading on a ship - which is about 2,000 head. In our country, there are currently only about 320,000 bulls, cows, and calves together.
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