Usage of irrigation elements by means of water-efficient technology in irrigating intensive apple gardens through soil and dynamics of seeping moisture

. The article presents the results of theoretical and experimental research on the cultivation of intensive orchards with the method of watering through the soil. These methods and elements are for the first time applied to intensive gardens. During the research, we studied both the movement and height of the wetting contour over time H , the radius of the width L , and the curve area of the irrigation norm W m 3 /ha were relatively chosen.


Introduction
As you know, in the world, including in Uzbekistan, agriculture has become the most significant land on the globe.The more the world's population grows, the more the need for food increases, so all countries are trying to find a solution to meet this need.Some environmental issues such as land development, land reclamation, overpopulation, food shortages and soil erosion, water shortages and other issues are causing people to look for more efficient ways to grow crops.
Currently, there are various methods of watering intensive gardens, which differ from each other.These are surface irrigation, drip irrigation, furrow irrigation, local irrigation, partial irrigation and so on.Under watering is one of the most effective methods of watering from the soil.
The proposed intra-soil irrigation has a typical nature of this irrigation is that water and mineral fertilizers dissolved in water are applied not on the soil surface, but directly on the soil layers with local moistening of it at the locations of the plant roots, which improves the optimal regimes of water, air, thermal and nutritious, and saving water.
According to literature studies, it was studied that the first experiments on subsoil irrigation were carried out in France in the 1850s, and in 1913 in the USA, experiments were first carried out using ceramic drainage pipes for irrigation through the use of moistening tubes [1].Research into subsoil irrigation in Russia began in the 20th century by V. G. Kornev, who proposed the idea of a vacuum-automatic subsoil irrigation system.
The systems used for subsoil irrigation differ mainly in the following principles: according to the principle of water entering the soil and according to the method of installing humidifiers [2].According to the technology of work, it can be divided into three groups (Figure 1).The advancement of science and industry allowed experts to create agricultural irrigation systems from polymer materials.Since in-soil irrigation irrigating pipes are made of polyethylene and it is possible to install special water dispensers, the construction of the system for using polyethylene pipes in subsurface irrigation is much more affordable and reasonable, besides laying of these pipes is completely mechanized [3][4][5].
Numerous Russian and foreign researchers studied the mode, technique, and effectiveness of subsurface irrigation in their research: V. P. Ostapchik, V. G. Karpiy, V. G. Kornev, M. S. Grigorov, N. R. Khamraev, V. G. Laboda, J. Philip, W. Mitchell, G. Toumon, D. Edwards, J. Robins, W. Gardner and others [6][7][8][9].After all of the studies had been conducted based on the data, many experts concluded that crops yield higher when it is irrigated with in-soil irrigation compared to other traditional and modern methods.
Soil moisture reserves are formed as a result of its interaction with vegetation and weather conditions [10,11].Quantitative indicators of the amount and movement of soil moisture are one of the most important factors characterizing the water regime formed in agricultural lands.Scientists V. R. Ridigerom, V. G. Kornevym, A. A. Bogushevsky, V. P. Ostapchikom, V. I. Bobchenko, L. E. Chernyshevskoy, A. A. Alesashenko on the study of moisture distribution laws in TIS.According to the research's results that the wetting contours are different in the ground with different mechanical compositions, in light soils, they extend downwards, while in heavy soils they expand horizontally [12,13].

Materials and methods
The subsoil technology recommended by us is the latest scientifically based innovation of water-saving technology for the organization of irrigation of intensive gardens from the inside of the soil and gives a positive result of the application.According to the new scheme, we have developed a new design of the element with which it is possible to provide intravenous irrigation and received patents for utility models of the Republic of Uzbekistan.No. Uz FAP 01336-devices for subsoil irrigation and RUz.No. Uz FAP 01337 -drip irrigation systems [3,19].In Uzbekistan, the concept of subsoil technology has been improved based on the goal of studying the almost complete absence of technology for local irrigation of the root system of apple orchards with irrigation of intensive orchards through the soil (Figure 2).
In this case, two methods can be used.The first method uses direct speech water, and the second, using underground water, is pumped into the pool with the help of a pump, after a certain time it moves with nutrients and passes through filters, after which it is sucked up by the second water pump for intrasoil circulation.
At the next stage, mineral fertilizers are mixed using special mixers (separators) and sent to the main pipeline at a pressure of 1.5-2 atmospheres, from it into thin pipes and from there to the elements of subsurface irrigation for an average of 3-3.5 water leaks from the elements subsoil irrigation per hour.Fig. 2. The design scheme and main parameters of the irrigation element from the soil: a -the distance between droppers, b -the distance between trees, The subsurface irrigation system includes the following elements: 1) water source (cooler, pond); 2) pump device; 3) equipment for preparing and adding fertilizers to water; 4) water filtration equipment; 5) main pipeline; 6) distribution pipes; 7) devices connecting system parts; 8) pressure regulators; 9) in-soil irrigation element humidifier; 10) control -measuring equipment.
The subsoil system works according to the simple scheme of the working part of the subsoil irrigation element mode, and its main parameters work in the following order: the subsoil irrigation system is made of polyethylene pipes and includes a reservoir, water treatment, water supply, water distribution and irrigation.Being highly dependent on the location of the working parts of the system, the type and number of elements included in the system may differ from others.
The water-storing part of the system -from ponds, clarifiers, or tanks, the waterpurifying part -from sand, disk, or various filters, the water-supplying part -from sand, disk, or various filters, the water-supplying part -from pumping devices, head and distribution pipes, the water-correcting part -from various valves, valves and fittings, the irrigation part -a pile.Since it consists of a humidifier, it supplies water leakage from pipes regularly in moderation.
According to our research, when applying the technology of subsoil irrigation, depending on the soil and climatic conditions, types of garden seedlings and the age of the tree around it at an angle to the horizon, from 2, 3 and 4 elements of subsoil irrigation can be installed.The conducted studies showed that at different values of the installation angle of the subsoil irrigation element relative to the horizon, it was noticed that the limits of the soil moisture field may be different, since the water release is closely related to the change in the distance between the holes.To achieve the optimal moistening area, changes in the contours of moistening the element of subsoil irrigation in laboratory conditions were studied in the variants of installation angles 30 0 , 45 0 and 60 0 (Figure 3).Installation of the subsoil element at different angles (Figures 3, a, b, c).Setting the element of subsoil irrigation at an angle to the horizon at 30 0 in this case, the length of the element is 0.5 m, the horizontal length is 0.43 m and the vertical length is 0.25 m, and in this case the height to the first tap is 0.11-0 ,16 m (Figure 3, а).Setting the element of subsoil irrigation at an angle to the horizon at 45 0 in this case, the length of the element is 0.5 m, the horizontal length is 0.45 m and the vertical length is 0.25 m, and in this case the height to the first tap is 0.11-0 ,16 m (Figure 3, b).Setting the element of subsoil irrigation at an angle to the horizon at 60 0 in this case, the length of the element is 0.5 m, the horizontal length is 0.42 m and the vertical length is 0.25 m, and in this case the height to the first tap is 0.11-0 ,16 m (Figure 3, c).
When irrigating intensive gardens from inside the soil, the recommended installation dimensions of the humidifier around the tree relative to the horizon are as follows (Figure 4).How to install the humidifier around a tree: a) The figure shows a construction drawing of an irrigation element installed at an opposite angle in a straight line, in which the total irrigation length was 0.8 m when it was installed around a tree from two sides.The humidifier is installed in parallel at a distance of 0.2-0.4m from the tree trunk in cross section, at which the humidification area is wider than in Fig. 4 (Fig. 5).

Results and discussion
According to the results of an experimental study carried out in the open field on soil moistening on the dependence of coals of elementary and their wetted coefficients on the dependence (h) and (k), width radius L, the contour area S m 3 , and contingently the value of the irrigation rate W m 3 /ha were determined accordingly.
Selected angles vertically (h) horizontally (k) is calculated by formula: The moisture distribution coefficient is determined by the formula: F с � h • k humidification vertically (h) and horizontally (k).The results of the experiment are shown in table.As can be seen from Table 1, the soil moisture when the element is installed at 45 0 is greater than the moisture at the angle of 30 0 -0.1075 and the moisture at the angle of 60 0 -0.1071.
In order to substantiate the optimal parameters for installing an irrigation element from the soil of apple orchards, installation options at an angle � � 30 � , � � 45 � , and � � 60 � relative to the horizon were considered.When installing the irrigation element from inside the soil, its dimensions were calculated along the vertical and horizontal axes, and the maximum value of the wetting surface F с was F с =0.126 when � � 45 � was set.Wetting efficiency was determined by determining the moisture distribution efficiency coefficient K c .When the subsoil irrigation element is installed at an angle � � 45 � relative to the horizon, the vertical length of the moistening of the wetting area along the length of the subsoil irrigation element is h=0.7 m, the horizontal length is k=0.5 m, the moisture distribution efficiency coefficient is Ks=1, was equal to 4. High efficiency was achieved by installing the subsoil irrigation element at � � 45 � [16,18].

Conclusion
According to theoretical and experimental studies, they came to the conclusion that intensive gardens need to be watered from the inside of the soil, and at the same time save water reserves, namely, satisfy the needs of plants in water due to less water consumption, and not excessive use of it, preventing water evaporation and obtaining abundant water.
Researchers have proven that with subsoil irrigation, the amount of water consumption can be reduced by 2-3 times compared to surface irrigation and by 15-20% compared to drip irrigation.Also, rows of seedlings in intensive gardens prevent the growth of weeds, create conditions for the normal growth and development of seedlings, and protect them from infection with various diseases [3,19].

Fig. 3 .
Fig. 3. Structural angles and dimensions of the element when installing the subsoil irrigation device a) irrigation element from the soil surface to the horizon relative to the angle of 30° when installed; b) the irrigation element from the soil surface to the horizon relative to the 45° angle; and c) the irrigation element from the soil surface to the horizon relative to the 60° angle for installation.

Fig. 4 .
Fig. 4. View of the irrigation element from the soil mounted opposite each other in a straight line.

Fig. 5 .
Fig. 5. View of the irrigation element from the soil mounted in parallel.

Table 1 .
Results of experimental research.