Alfalfa different irrigation technology comparison is the deep roots of alfalfa is a perennial crops, planting area is wide, with the continuous development of grass industry, alfalfa production also gradually incline to large-scale, intensive, mechanization production mode, irrigation is one of the most important link in alfalfa production management, is directly related to on the yield and quality of the product.

There are many shortcomings in traditional alfalfa irrigation: low water use efficiency, unsuitable for areas with water shortage, frequent occurrence of diseases and insect pests, limited fertilization methods, and difficult control of vegetative growth and reproductive growth.

Pivot has good uniformity of irrigation (saving water and increasing production), strong adaptability (water source, terrain and soil), easy integration of water and fertilizer, high degree of mechanization (saving labor and time), high degree of automation, large control area and long service life.But has the initial investment high, the earth Angle leakage, suffers the wind speed influence and so on the shortcoming.

Coupling test of water and fertilizer of alfalfa with pivot:

The test site is located in the Saiwusu area of the Etok banner, belonging to temperate semi-arid grassland climate. The average annual temperature is 6.5~7.5℃, the daily range is 13.9℃, the average annual precipitation is 200~250mm, and the average annual evaporation is 2400~2500mm.Soil type: sandy loam;Soil bulk density: 1.3g/cm (0-30cm);Field moisture capacity: 19.8% (mean 0~30cm)

Test results:

After optimizing the configuration of the pivot nozzel, the uniformity of irrigation was obviously improved.The control area of the tail gun is 1/3 larger than the average sprinkler irrigation water depth of other control areas, which reduces the uniformity of sprinkler irrigation of the whole machine.

The annual water demand of alfalfa during the whole growing season is about 469.37mm.The irrigation should be reduced in the first green regeneration period combined with the moderate growth condition of the plant.. The water consumption of alfalfa in each branch period and budding period is large, and it is suggested that no irrigation should be used in the flowering period.

The first crop contributed the most to the total annual output, and the output of each crop gradually decreased.80%ET did not cause a decrease in alfalfa yield, but 60%ET resulted in a significant decrease in alfalfa yield.

In the same crop, the WUE level is largely determined by the irrigation amount: irrigation amount decreases, WUE increases.The coupling effect of water and fertilizer was not obvious during the whole growth season.

Considering the effects of different water and fertilizer treatments on alfalfa yield, growth and quality, and considering the water use efficiency, it is suggested that irrigation of alfalfa stubble in semi-arid areas of Inner Mongolia should be treated by 80%ET.

Fertilization reference: 180kg/hm2 potassium dihydrogen phosphate was used in the first crop, 105kg/hm2 nitrogen fertilizer was used in the second crop, and 60kg/hm2 nitrogen fertilizer was used in the third crop.

New technology application of pivot:

(1)nozzle selection, configuration and optimization

(2)Application of water and fertilizer integration technology

(3)Wireless remote control management system

(4)Variable irrigation fertilizer control system

According to the requirements of specific land boundary, soil characteristics and crop water demand, differential variable irrigation is implemented. Solenoid valves are installed in parallel for each sprinkler head or several sprinkler heads. Variable irrigation is implemented by controlling the solenoid valve (changing the opening and closing time ratio of the solenoid valve) to change the amount of water spraying.

GPS/ beidou positioning, RFID block boundary identification, automatic shutdown and zone irrigation.