With the support of the GEF Small Grants Program in Uzbekistan, in order to test and introduce zero-tillage, since 2010 in the Kanlykol region of the Republic of Karakalpakstan, the project "Implementation of soil protection technologies" is being implemented. Within the framework of the project, special equipment was purchased and zero-sowing was tested in the conditions of Karakalpakstan, and the impact of zero-till methods on soil moisture, productivity and economic efficiency of the main crops cultivated in Karakalpakstan was assessed. In the article below, you can read some of the lessons learned from implementing this practice.

Background and problem statement

There are several reasons for soil degradation in Karakalpakstan, and they are all interrelated:

• loss of soil productivity due to depletion of the humus content in the soil - the humus content in the soil ranges from 0.4%, which corresponds to a very low content, to 1%, which corresponds to the level of the average degree of soil humus supply1. The average soil bonitet score in the northern regions of Karakalpakstan is 41-48 points;
• an increase in the content of salts in the soil - 95% of the irrigated sown areas of Karakalpakstan are prone to salinization (Abdullaev, 2011);
• loss of productive soil layer due to wind and water erosion - per year from 1 hectare of land due to wind erosion, we lose from 53 to 130 tons of fertile soil layer. We do not notice this loss, because this corresponds to only 5-10 millimeters of the topsoil. But we do not remember that it takes 70-150 years for the formation of 1 cm of the fertile layer in our arid conditions.

In addition, the number of dry, dry years is increasing, which further complicates farming in our arid region.

But, unfortunately, farmers in many cases are struggling not with the causes of low fertility, but with its consequences.
Let's name just a few factors that have an extremely negative effect on the preservation of soil fertility:

Excessive machining.

Every year, each farmer carries out about 4-5 operations on mechanical disturbance of the soil. Plowing, harrowing, milling accelerate the mineralization processes in the upper layers of the soil and initially have a positive effect on plant growth, and hence the harvest of crops. However, these routine activities, which have been used by farmers for hundreds of years, have a number of important negative factors that negatively affect soil fertility.

By exposing bare soil to high air temperatures and drying sun, over-machining actually results in crumbling of soil particles, which subsequently leads to a high level of wind blowing of the soil. As a result, these operations contribute to wind erosion.

Excessive use of water.

Unfortunately, there is a funny collision - we have little water in our country, which is not enough for all farmers. At the same time, every farmer who has access to water tries to supply as much water as possible to the field, as if in reserve. Virtually every farmer who over-irrigates his field "steals" this water from other farmers who may not have access to water. But most importantly, a lot of water in the field only leads to negative consequences.

Excessive water leaches important minerals and nutrients from the soil. For example, now every year only 3000 to 6000 m3 of water per hectare is consumed here for washing the soil from salts. Such abundant leaching irrigation leads not only to the washing away of salts into the underlying soil layers, but also nutrients, such as nitrogen and potassium, necessary for the growth and development of plants.

Often, instead of reducing soil salinity by flushing out salts from the soil, over-watering, on the contrary, draws up groundwater, with a high salt content, which remains on the soil surface after the water itself evaporates. Those. the farmer himself contributes to the accumulation of salts in the upper soil layers.

In addition, it is not a secret for anyone that farmers often use already mineralized water for irrigation. If we assume that the salinity of the water is only 0.5 g / liter, each extra cubic kilometer of irrigation water brings an additional 500 kg of salt to the soil.

Soil depletion is a widespread and direct threat to the country's sustainable agricultural development and food security.

Possible Solution

One of the advanced soil-protective, moisture-saving technologies that contribute to the increase in soil fertility is zero tillage - a new and unusual technology for our farmers, which is increasingly used all over the world.

Zero-tillage is direct sowing on stubble and crop residues saved from the previous harvest, without any tillage, using a dedicated seed drill with a disc coulter. It aims to restore and maintain soil fertility through natural processes in the soil.

The basic principle of no-till is to recreate natural conditions for the life of soil invertebrates and microorganisms, which contributes to the gradual restoration of the lost soil fertility and its sustainable preservation.

The technology is especially relevant for arid zones, where there is little rainfall and the risk of crop failure is very high in dry years. Therefore, in our opinion, zero tillage is especially relevant today for the agriculture of Uzbekistan as a whole and for Karakalpakstan in particular, where soil fertility is steadily declining, and the risk of crop failure is constantly growing due to frequent low water levels.

If you list the main advantages of zero processing, they are:

Reproduction of soil fertility - all zero-till techniques together contribute to increasing the biological activity of the soil. Maintaining conditions for the vital activity of soil microorganisms (absence of temperature and air stress) makes it possible to activate the processes of restoring soil fertility as a result of natural processes. Leaving plant residues is food for microorganisms, which convert them into humus. Each ton of straw gives 170-180 kg of humus, while a ton of manure gives only about 65-75 kg of humus (Lykov A.A., "Agriculture" textbook for universities, M. "Agropromizdat", 1991, 77p.). An increase in the content of organic matter in the soil contributes to an increase in crop yields.

Soil Moisture Conservation - One of the main no-till techniques is to preserve stubble and crop residues, or better yet, to create mulch on the surface of the soil. Mulching in arid regions reduces evaporation from its surface, lowers the temperature of the soil surface, and therefore retains the accumulated moisture and allows plants to use it economically during the growing season, thereby reducing the need for plants for irrigation, which is very important in years of low water. Our research has shown that the soil cover with straw contributes to the preservation of soil moisture in the upper 0-5 cm layer by 3.2-4.2 times and 5-10 cm of the layer 1.2-1.5 times more than the uncovered area. The soil moisture retained due to the covering with straw, according to our calculations, is equal to 233.4-276.9 m3 of water per 1 hectare. Judging by the intensity of soil moisture evaporation in a field with a cover, according to our calculations, it will be possible to reduce at least 2 irrigations during the growing season, that is, at a rate of 500 m3 / ha, water savings will be 1000 m3 / ha.

Decrease in seasonal salt accumulation - preserved plant residues reduce evaporation from the soil and reduce seasonal salt accumulation by 1.6-4 times compared to a plot without vegetation. Crop residues and reduced salinity also reduce flushing water consumption rates. For example, in our case, when mulching with straw, it was possible to maintain the degree of salinity at a low level (0.2-0.5% for dense remainder). With a low degree, the leaching rate is 3000 m3 / ha, and with a medium degree - 4000 m3 / ha. This means that when mulching, there is a real opportunity to reduce at least 1000 m3 / ha of water used for flushing. Thus, by preserving soil moisture during the growing season and by reducing salt accumulation by mulch, it is possible to reduce the total water consumption by 2000 m3 / ha annually.

In reducing the costs of the farmer for the cultivation of crops - in the course of monitoring the yield and the cost of cultivating cotton and winter wheat for no-till, it was revealed that, despite the relatively low yield, the profitability was higher compared to conventional cultivation. In 2011, crop yields were extremely low due to the lack of irrigation water. Thus, the yield of winter wheat with no tillage was 18.9 c / ha, and with conventional cultivation - 23.3 c / ha. Despite the relatively low yield of winter wheat under no-till, the profitability rate was 17.2 percent higher than with conventional tillage. No-till seed cotton yields were 6.9 c / ha lower than conventional tillage, but despite this, no-till yields were 11.8 percent higher than conventional tillage. A high level of profitability has been achieved due to the reduction of material and labor resources for the cultivation of crops. So, for example, with the cultivation of winter wheat by no-till, fuel costs were reduced by 62 percent, and with the cultivation of cotton by 80 percent.

Table 2. Economic efficiency of cotton cultivation in the Kanlykol region of the Republic of Kazakhstan (2011)

Not all crops are suitable for no-till. Our studies have shown that crops such as indigofer, fodder beets and some other vegetable and melon crops cannot be sown with zero tillage. Crops such as wheat, triticale, corn, sorghum, sunflower, soybeans, mung bean, sesame and others are especially well suited for no-till - they grow and thrive with no-till, even in the early years of application.

Despite the existing merit, zero-till is not immediately accepted by farmers. Below we have tried to collect experiences of the challenges faced by the zero-seeding initiative:

1. Psychological problem

An important role is played by a purely psychological attitude to the issue of land cultivation. After all, not everyone is able to abandon the usual method of plowing the land used for thousands of years. It is not easy for farmers to give up the idea that plowing and other types of tillage may not be the most effective and even detrimental to the soil - this is how the land has been cultivated for centuries. We spoke about the disadvantages of mechanical action above. But the facts indicate an increase in soil degradation, and this suggests that natural processes are disturbed. In such cases, the only salvation is to try to reproduce the laws of nature and its natural processes. Farmers, as well as leaders of the agricultural sector, find it difficult to accept the self-regulating processes of nature, and the fact that plowing should not be carried out by heavy tractors with plows, but, as D. Mendeleev pointed out more than a hundred years ago, natural processes (soil organisms, soil shading plant residues, frost-defrosting of soil layers, root litter). Zero-tillage is primarily based on these natural processes.

2. Low yield in the first years of application

There is a risk of a decrease in yield by 5-10 c / ha when switching from traditional to zero tillage technology in the first years of the technology application. This is understandable because the soil in a no-till field has not yet naturally “loosened” the soil. As studies of scientists and practitioners in many countries show, the loose state of the soil with no-till is achieved only after five years of its permanent use. The decrease in yield in the first years is compensated by an increase in yield in subsequent years and a higher profitability of the technology.

3. Untidy appearance of the field

With zero processing, the field does not always look neat, which intimidates anyone who is not aware of the existence of zero processing. This fact is very encouraging for opponents of zero processing, who are always looking for flaws in order to prove their case that “zero processing is not possible in our conditions”. This fact also scares the farmers. Again, in our conventional understanding, plant debris on the surface of the field does not allow the field to look sufficiently well-groomed and clean. However, plant residues improve the soil from year to year, and this is the most important thing.

4. The presence of weeds

There is a risk of contamination of crops by perennial weeds and shrubs. In many countries, for effective weed control 20 days before sowing, glyphosate herbicides are used at the rate of 5 liters / ha. Since any chemical contaminates the soil and the prices of herbicides are quite high, we recommend using another, cheaper, but more time-consuming method of weed control - hand weeding.

There is also a mechanized method - flat-cut loosening, which simultaneously loosens the subsoil compacted layer and cuts off the roots of weeds, while the top layer with stubble and plant residues remains intact and intact. Flat-cut loosening is loosening the soil without wrapping the layer while keeping the stubble on the surface.

5. Availability of technology when you need it

Farmers often do not have a powerful tractor to lift the planter. Zero drills are usually heavy, so they are able to cut through the straw layer to sow seed to a predetermined depth. Farmers are forced to rent a tractor in the district MTP. However, during the season, the MTP provides tractors only for plowing fields for the main crops: wheat, cotton. Only after fulfilling the plan for state-ordered crops can the tractor be received for zero-tillage. But then the sowing deadline had already passed. We had to cultivate winter wheat and other summer crops late, which affected yields. In order to successfully implement any method or technology, the best example of the method or technology must be demonstrated. Farmers, until they see with their own eyes all the benefits of technology, will not risk using it. Unfortunately, we have not yet had the opportunity to show an example of the ideal application of zero tillage, because we always got the tractor at the very last sowing date, that is, after the fulfillment of the plan for the state order. Despite such obstacles, we have gained sufficient experience in the cultivation of crops using this technology (when and in what conditions what crops can be sown, when Not all crops are suitable for no-till. Our studies have shown that crops such as indigofer, fodder beets and some other vegetable and melon crops cannot be sown with zero tillage. Crops such as wheat, triticale, corn, sorghum, sunflower, soybeans, mung bean, sesame and others are especially well suited for no-till - they grow and thrive with no-till, even in the early years of application.

Despite the existing merit, zero-till is not immediately accepted by farmers. Below we have tried to collect experiences of the challenges faced by the zero-seeding initiative:

1. Psychological problem

An important role is played by a purely psychological attitude to the issue of land cultivation. After all, not everyone is able to abandon the usual method of plowing the land used for thousands of years. It is not easy for farmers to give up the idea that plowing and other types of tillage may not be the most effective and even detrimental to the soil - this is how the land has been cultivated for centuries. We spoke about the disadvantages of mechanical action above. But the facts indicate an increase in soil degradation, and this suggests that natural processes are disturbed. In such cases, the only salvation is to try to reproduce the laws of nature and its natural processes. Farmers, as well as leaders of the agricultural sector, find it difficult to accept the self-regulating processes of nature, and the fact that plowing should not be carried out by heavy tractors with plows, but, as D. Mendeleev pointed out more than a hundred years ago, natural processes (soil organisms, soil shading plant residues, frost-defrosting of soil layers, root litter). Zero-tillage is primarily based on these natural processes.

2. Low yield in the first years of application

There is a risk of a decrease in yield by 5-10 c / ha when switching from traditional to zero tillage technology in the first years of the technology application. This is understandable because the soil in a no-till field has not yet naturally “loosened” the soil. As studies of scientists and practitioners in many countries show, the loose state of the soil with no-till is achieved only after five years of its permanent use. The decrease in yield in the first years is compensated by an increase in yield in subsequent years and a higher profitability of the technology.

3. Untidy appearance of the field

With zero processing, the field does not always look neat, which intimidates anyone who is not aware of the existence of zero processing. This fact is very encouraging for opponents of zero processing, who are always looking for flaws in order to prove their case that “zero processing is not possible in our conditions”. This fact also scares the farmers. Again, in our conventional understanding, plant debris on the surface of the field does not allow the field to look sufficiently well-groomed and clean. However, plant residues improve the soil from year to year, and this is the most important thing.

4. The presence of weeds

There is a risk of contamination of crops by perennial weeds and shrubs. In many countries, for effective weed control 20 days before sowing, glyphosate herbicides are used at the rate of 5 liters / ha. Since any chemical contaminates the soil and the prices of herbicides are quite high, we recommend using another, cheaper, but more time-consuming method of weed control - hand weeding.

There is also a mechanized method - flat-cut loosening, which simultaneously loosens the subsoil compacted layer and cuts off the roots of weeds, while the top layer with stubble and plant residues remains intact and intact. Flat-cut loosening is loosening the soil without wrapping the layer while keeping the stubble on the surface.

5. Availability of technology when you need it

Farmers often do not have a powerful tractor to lift the planter. Zero drills are usually heavy, so they are able to cut through the straw layer to sow seed to a predetermined depth. Farmers are forced to rent a tractor in the district MTP. However, during the season, the MTP provides tractors only for plowing fields for the main crops: wheat, cotton. Only after fulfilling the plan for state-ordered crops can the tractor be received for zero-tillage. But then the sowing deadline had already passed. We had to cultivate winter wheat and other summer crops late, which affected yields. In order to successfully implement any method or technology, the best example of the method or technology must be demonstrated. Farmers, until they see with their own eyes all the benefits of technology, will not risk using it. Unfortunately, we have not yet had the opportunity to show an example of the ideal application of zero tillage, because we always got the tractor at the very last sowing date, that is, after the fulfillment of the plan for the state order. Despite such obstacles, we have gained sufficient experience in the cultivation of crops using this technology (when and in what conditions what crops can be sown, when to water, etc.).

In addition, along with the diffusion of technology, it is necessary to develop the supply of zero drills or establish their local production.

6. Technique for mulching

We got excellent results even when there was only stubble left in the field. This allowed to cover the surface of the soil, but not completely shade it. Unfortunately, the combines do not have accessories for chopping and spreading straw. Chopping up the straw and spreading it evenly over the soil surface would further enhance the positive effects of no-till. We did not take this important factor into account and needs to be corrected. In addition to no-seeders, units are also needed to mulch crop residues and distribute them evenly over the soil surface. All Keys and Klaas combines were previously equipped with straw choppers-spreaders, unfortunately, the machine operators removed them for some reason (rather, they considered them superfluous). For crushing plant residues, it is possible to use Polesie, Jaguar, KIR-1.5M, KIP-1.5, Kiwi aggregates, which are used for grass ensiling. And the Kiwi straw chopper is multifunctional in its use: it selects straw swaths after any domestic or foreign grain harvesters, double straw chopping, scattering of chopped straw across the field. The shredder is designed with the knowledge that straw plowed into the soil is an organic fertilizer that increases fertility and contributes to the development of beneficial soil microflora (Kiwi price on the Internet is about $ 4,000).

7. Lack of administrative support

Attempts to keep at least one field under no-till for a long time have been unsuccessful. All farmers have a compulsory plan for plowing fields after harvesting wheat (the so-called "peshma-pesh", which means the combine has passed and the plowing unit immediately followed), which is strictly controlled by the management. The results that the project was able to obtain - two years of application of the zero-seeding technique. We have not yet been able to obtain the impact of the continuous application of zero treatment for three or more years.

The practical results obtained indicate the possibility and feasibility of a gradual transition to zero processing. It allows you to reduce the cost of production, which is very important in a market economy, to reduce the risk of not receiving a crop due to the conservation of soil moisture, especially in dry years, to significantly save the country's water resources, and to gradually restore soil fertility.

In conclusion, we would like to offer you a simple way to make sure of the need to implement this technology:

Try the loose soil at the edge of a field that has never been plowed. See how wild plants thrive there. At the edge of a field where machinery cannot enter and the soil has never been plowed, just sow a few cotton seeds (our main crop). You will see how good the growth and development of plants growing on this part of the earth have.

Compare their development to the plants in the plowed part of your field.

On one of the days of the field for farmers, the participants could see for themselves how the plant grows and develops better where the soil has never been plowed. This gave a stunning effect and many were surprised by this fact. After that, several more farmers agreed to test zero till in their fields.

Thus, after the pilot project, the following conclusions can be drawn on the introduction of zero-seeding technology in Uzbekistan:

• It is necessary to continue the work on the transition of farmers to this technology. But for this it is necessary to show all the benefits of the technology in the best conditions. It is necessary to demonstrate zero tillage in one field permanently for at least five years, that is, until the soil fertility is restored under the influence of natural processes. We appeal to the khokimiyats of districts and regions - if you have an interest in this technology, and you want to support the work on its implementation, the PMGEF is ready to support this work;
• Once every 5-6 years, it is advisable to carry out deep loosening with a flat-cut ripper, which does not disturb the top layer with stubble and straw. This will allow you to get rid of weeds and destroy the compacted underlying soil layers;
• It is advisable to use additional equipment for mulching and even distribution of mulch over the surface of the field to enhance the effect of covering the soil with plant residues;
• Demonstrate the effectiveness of the technology in stressful conditions - in low water conditions. This will no doubt increase public confidence in zero-processing;
• Strengthen the promotion of the method among farmers and decision-makers - khokimiyat officials, ministries and departments, to increase support for the implementation of the method. It is also necessary to continue work on improving the qualifications of agricultural workers, to train young scientists using this methodology, to familiarize themselves with the experience of other countries. about this practice, etc .;
• Continue work to involve businesses in the zero-till technology space - traders selling and leasing zero-seeding equipment, mulching equipment, as well as production structures for possible local production of such equipment.

Aybergenov B., Volkov A.

1 Report of the Soil and Land Management Consultant of the FAO Project "Sustainable Agriculture Practices in the Drought Affected Region of Karakalpakstan", 2006