Abstract: An experiment shows that it takes 0.56 m³ of water for Siberian wildrye to produce 1 kg of hay in the first year,and 0.498 m³ of water to do the same in the second year. It takes 2.766 m³ of water for the grass to produce 1 kg of seed. The first year’s highest water consumption period falls on the heading stage,which amounts to 94.35 m~2/hm² a day.The second year’s highest water consumption period lasts from the stem pushing to be heading stage,amounting to 122.1 m³/hm² per day.During the growth stage Siberian wildrye needs to the watered four to five times,preferably 2550～3000 m³/hm² each time to meet the need of the grass during its growing stage.

Key words: Grassland science, Siberian wildrye, Water need, Irrigation

摘要： 试验结果表明:生长第一年的老芒麦每形成1kg干物质需消耗0.56m³水,生长第二年需消耗0.498m³水,每形成1kg种子需要消耗水分2.766m³;老芒麦生长第一年耗水量最多在抽穗阶段,需水强度达94.35m³/hm²·d;生长第二年耗水最多在拔节到抽穗期,需水强度最高达122.1m³/hm²·d;全生育期灌水4～5次,每公顷灌溉定额2550～3000m³为好。

关键词: 草原学, 老芒麦, 需水, 灌溉