Soil Degradation — Can We Manage It?

Farmers should play the most active role in reducing soil degradation. This is the opinion of nearly 70% of the participants of last week's webinar “Soil Degradation — Can We Manage It?”

At the online event organized by the NIK, on the occasion of World Soil Day, it became clear that one of the most widespread practices for the prevention of soil degradation is tillage across the slope, as well as fertilization with manure.

Special guest speakers at the first of the series of webinars dedicated to soil health and sustainability were Prof. Dr. Ekaterina Filcheva — President of the Bulgarian Society of Humus Substances, Prof. Dr. Svetla Ruseva from the Department of Physics, Erosion, Soil Biota at the Institute of Soil Science, Agrotechnologies and Plant Protection” N. Pushkarov”, Prof. Dr. Margarita Nankova from Dobrudzhan Agricultural Institute — General Toshevo and Prof. Dr. Toma Shishkov from the Institute of Soil Science, Agrotechnology and Plant Protection “N.Pushkarov”.

As one of the most important resources on the planet, soil care and the problem of its degradation occupy an increasing place both in the developments of scientists and among the agricultural practices of farmers. This was the main focus of the discussion — the prevalence and dynamics of the problem at the national level. Experts in the field presented both data from long-term studies and practical advice on the possibilities of managing the process through agricultural practices.

‍

What are the causes of soil degradation?

Unilateral nitrogen fertilization

Measures to store humus in the soil?

The National Soil Conservation Program of the MOSW

‍

What are the causes of soil degradation?

“Protecting soil functions is very important because soil and its functions are threatened by a number of degradation processes. The main key to solving the problems related to soil degradation is the sustainable management of soil resources”, noted the first guest lecturer Prof. Dr. Svetla

According to her, sustainable management can be achieved in several ways:

• by maintaining soil diversity;
• through a balanced diet — i.e. appropriate fertilization, which ensures a sufficient and efficient supply of nutrients;
• by maintaining soil organic matter reserves by preserving plant residues on the soil surface;
• by regulating the temperature and water regime — this is achieved by maintaining the physical properties of the soil, mainly the soil structure;
• by combating erosion — part of sustainable soil management.

“Erosion is the greatest threat to soils on earth. It represents the removal of the most fertile surface layer of the soil by water, wind or tillage. Erosion occurs in all climatic conditions and depends on the climate, soils, terrain and vegetation. In the case of arable land, it reaches up to 450 tons/ha”, explained Prof. Dr. Ruseva.

She added that by 2050, soil erosion could cause up to a 10% reduction in crop production.

“If current agricultural practices do not change by 2050, a reduction in crop yields could be equivalent to a reduction in the area of agricultural land by one and a half million square km, which is almost all of India's arable land,” she warned.

In fact, it takes 1000 years to form 2-3 cm of soil.A curious but also worrying fact is that every 5 seconds, soil equal to 1 football field erodes on the ground.

Prof. Dr. Rusevaalso indicated 5 impacts of erosion on the soil, namely:

• Impaired soil health and productivity;
• Significant losses of soil biodiversity;
• Organic response to climate change;
• Increased risk of landslides and floods;
• Increased risk of soil and water contamination.

There are a number of sustainable practices that farmers can apply to deal with erosion. Some of them are:

• tillage of the soil along the horizontality of the terrain;
• anti-erosion crop rotations, minimum treatments (where and when possible);
• maintaining plant cover;
• construction of forest protection belts in the flat terrain and on terraces in the steep terrain.

Unilateral nitrogen fertilization

In addition to up-to-date information about the change in soil fertility in the Granary of Bulgaria, Prof. Dr. Margarita Nankova touched on another interesting topic for farmers, namely: unilateral nitrogen fertilization and answered the question “Is there any serious reason to reject this practice?”. He also explained what the use of high and aggressive soil norms of the order of 18 kg. act. in nitrogen/ha leads to, as an example, the results of a long-term study.

“Research that we have conducted over a number of years of experiments shows that in these places we have a decrease in the concentration and stock of organic matter. This fertilizer rate also affects up to the 4th meter of black earth, which already refers to relict soil, i.e. buried soil before the last ice age. We should treat with extreme caution such aggressive norms of nitrogen fertilization”, said Prof. Dr. Nankova.

Measures to store humus in the soil?

Another interesting topic that excites a number of farmers and was noted at the webinar is about the content of humus in the soil and, more precisely, what are the measures for its storage.

Prof. Dr. Ekaterina Filcheva shared with us about various agricultural practices, through which we can preserve organic carbon in the soil, dividing them into 5 main groups:

• Natural;
• Use of soil improvers;
• High-tech practices;
• Hydromelorative and anti-erosion activities;
• Reclamation activities;

Here from Prof. Dr. Ekaterina Filcheva we heard about manure fertilization, the use of composted organic materials, the cultivation of perennial grasses, and also — about plowing the soil. High-tech events focused on soil application of modified highly soluble polymers and structural agents, the use of seeds, after inoculation with rhizospheric microflora, treatment of plants with growth stimulants in order to increase biomass yield and others.

The National Soil Conservation Program of the MOSW

Prof. Dr. Toma Shishkov highlighted the priorities of the program and the directions that farmers can benefit from.

The priorities of the new program are:

• Improving administrative capacity and legal instruments
• Preventing the occurrence of degradation processes, restoring and preserving soil functions
• Sustainable management of soils as a natural resource and environmentally friendly land use
• Public engagement in the management, sustainable use and conservation of soils

And the planned directions with the participation of farmers and farmers are:

• Guideline 2.4 Minimising soil compaction
• Guideline 2.7 Conservation and enhancement of soil organic matter
• Heading 3.2 Development of agriculture towards improving soil fertility and sustainable soil management
• Strand 4.2 Improving awareness and relevance in relation to the implementation of good practices

The great interest in the first webinar in the series was proof that the topic of soil and its health is relevant and affects every farmer.

If you were unable to attend on the day of the event you may see the full record of the killer NOW

‍