Different ways of watering of agricultural cultures are given. Advantages and shortcomings of ways of an irrigation are noted. Recommendations for a right choice of a way of watering are made.
UDC 631
There are different ways of watering of agricultural cultures, the superficial irrigation, overhead irrigation and a microirrigation are basic of which.
Advantages of a superficial irrigation:
· A prostate and reliability in operation;
· Possibility to water at a strong wind;
· In comparison with systems of overhead irrigation and drop watering, small costs of construction.
Shortcomings of a superficial irrigation:
· It is a lot of manual operation;
· Big volume of planirovochny works at a difficult microrelief;
· Depression of structure of the soil and need for additional loosening of row-spacings;
· Unevenness of moistening of the soil along irrigation furrows and strips;
· High probability of a raising of level of ground waters with a zasoleniye or bogging of irrigated sites.
The primary majority of the irrigation areas in Ukraine irrigate with overhead irrigation. Key parameters for an artificial rain are the size of its drops, intensity and uniformity.
Drops of an artificial rain should be size of 1-2 mm. Intensity of an artificial rain should be such that rain water was used as much as possible by plants, without causing a superficial drain and a soil erosion. For the majority of dozhdevatel it makes less than 0,4 mm/mines (for comparison: average intensity of a natural rain – 0,004-0,1 mm/mines; for heavy rain average intensity reaches 2-10 mm/mines)
Reference. 1 mm of a precipitation equals 10 m3/hectares.
Uniformity of an artificial rain is the important characteristic. The factor of uniformity for natural rains makes not less than 0,86-0,91. In practice by dozhdevalny cars the rain with factor of uniformity of watering to 75 % is created.
Systems are divided by Dozhdevalnye on stationary, semiportable and mobile. - all elements can be moved to the mobile for watering of the different irrigated areas. Such systems form of mobile pump stations, fast-folding pipelines and different type of mobile dozhdevalny cars.
Watering in dozhdevalny systems make by cars of face-to-face and circular action, and also water sprinklers and by cars of drum-type type.
Advantages of overhead irrigation in comparison with superficial way of an irrigation:
· Favorable action on the soil and plants;
· Economy of irrigation water;
· Smaller threat of a secondary zasoleniye;
· Application possibility in the conditions of a difficult relief of a field;
· Economy of a hand labor;
· Mobility.
Overhead irrigation shortcomings:
· Considerable cost of creation of stationary systems and an energy expense for pressure creation in an irrigating network in comparison with superficial way of an irrigation;
· Having watered with sectors with zones of repeated watering and dry sites (at a circular way);
· During watering drops lenses which create conditions for development of diseases are formed;
· Inefficient distribution of water (row-spacings pour down also);
· An excessive consumption of water in comparison with systems of a drop irrigation.
The drop irrigation is a way of a local irrigation of the soil through drop water releases (droppers) in a zone of placement of root system of plants.
Distinguish stationary, seasonal and stationary and seasonal systems of a drop irrigation. Stationary systems have a network of the main and distributive pipelines laid underground, and local and irrigation pipelines are placed under/over the earth and should be executed from pipes of long-term use. Such systems use for an irrigation of vineyards and fruit plantings.
Systems of seasonal type mount on the beginning, and dismantle at the end of the vegetation period. Important feature of systems of a drop irrigation is high insistence to quality of irrigation water. Reliability of work and term of operation of irrigation pipelines essentially depends on this indicator. Therefore one of important elements is the filter for water.
Advantages of a drop irrigation:
· Careful, without a travmirovaniye of plants, watering;
· The thaw lenses on plants isn’t formed, it is possible therefore to water for days;
· Economy of water (watering of belokachanny cabbage – 30-50 m3, and at overhead irrigation – from 250m3 for one watering, carrots – 50-120M3 and 200-400 m3 respectively);
· Local, economic introduction of SZR and ameliorants without costs of fuel;
· The economy of electric energy if to compare to overhead irrigation, at the expense of reduction of working pressure of an irrigating network in 3-5 times;
· For 30-50 % efficiency of digestion of fertilizers thanks to their introduction with irrigation water on root system raises.
One of barriers to acquisition of system of a drop irrigation – the price. However, the additional crop which has been grown up thanks to this system, for one-two vegetations completely pays back system of drop watering.
Summing up stated, it is necessary to note that for a right choice of a way of an irrigation it is necessary to define: first, type of a crop rotation and specific structure of cultures in an economy adjusted for weather conditions of the region and structure of soils. Secondly, to "adhere" purchase and system installation to long-term plans of production.
Thirdly, to understand that watering is an intensive step to production therefore it it is economically unprofitable to use at low level of fertilizer, protection and agricultural technicians.
And main thing: the irrigation is a guarantee of a stable crop under condition of a drought which occurs in Ukraine each four-six years.
(On Propozits_ya magazine materials).