Water requirement regularity and irrigation quota of alfalfa in Ar Horqin Banner

To provide a scientific basis for alfalfa irrigation in Ar Horqin Banner, 30 years of meteorological data (from 1984 to 2013) and the FAO Penman-Monteith equation were employed to study the water requirement regularity and irrigation quota of alfalfa. The results showed that the water requirement of alfalfa for the first to fourth harvests, growing season, non-growing season, and full year in Ar Horqin Banner were 221, 187, 169, 179, 755, 70, and 825 mm, respectively. The water requirement rates were 4.3, 4.7, 4.1, 2.5, 3.7, 0.4, and 2.3 mm·d-1, respectively. The irrigation requirements were 194, 118, 66, 131, 508, 56, and 564 mm, respectively. The irrigation quotas were 228, 139, 78, 154, 598, 66, and 664 mm, respectively.