黄土高原牧草耗水规律研究

A STUDY OF THE REGULARITY OF WATER CONSUMPTION ON THE LOESS PLATEAU

黄土高原旱作牧草所需水分是大气降水通过纳、存而起着调节和再分配的作用。草地的水分主要消耗于植株的蒸腾和棵间蒸发,其耗水量与牧草品种、发育阶段、产量、自然条件等有关,其耗水的高峰期是牧草生殖生长最旺盛时期。日耗水量强度的变化曲线呈抛物线状。

In the loess plateau,water obsorbed by rainfed forage crops comes from rainfall always whith is stored in soil. The soil plays a role in moisture adjusting and redistributing. The soil moisture in grassland is mainly consumpted in plant transpiration and soil evaporation. The water consumption is related with forage cultivars and their growing stages,yields, environmental conditons ,and so on. The peak period of water consumption is the period of reproducting growth of forage crops. The variation curve of diurnal water consumption is just like a parabola.