春小麦蒸发蒸腾的调控

Regulation of Evapotranspiration of Spring Wheat

春小麦蒸发蒸腾受环境条件、土壤水分状况和小麦叶片气孔的综合调控。甘肃河西地区辐射强烈,与春小麦蒸发蒸腾具有高度相关性性(r>0.95),决定了该地区作物的高耗水特性。土壤水分条件在水势为-0.01—-0.1MPa时,春小麦蒸发蒸腾受气象条件影响和小麦叶片气孔调节的作用较大;当土壤水势降至-0.3—1.5MPa时,叶片气孔开始关闭,太阳辐射对春小麦蒸发蒸腾的作用明显减弱(相关系数r<0.31)。土壤水分条件的恶化是影响春小麦生长和蒸发蒸腾的主要限制因子。

Evapotranspiration of spring wheat is affected by weather conditions, soil moisture and activity of leaf stoma. Water consumption of spring wheat in the irrigated region studied is very high (437.2 mm)because solar radiation in Hexi oasis, which is the leading factor of meteorogical condition, is very strong and closely related to evapotranspiration of spring wheat (r>0.95). When soil water potential varies between -0.01 MPa and -0.1 MPa, evapotranspiration is mainly affected by meteorological factors and regulated by leaf stoma. When soil water potential falls below -0.3 MPa, leaf stoma begins to close and the effect of solar radiation on evapotranspiration decreases evidently. Soil water deficit is the main limiting factor affecting the growth and evapotranspiration of spring wheat.