风速对盆栽苋菜蒸腾及物质积累的影响

Effect of wind speed on transpiration and biomass accumulation of potted amaranth

通过温室盆栽试验,研究了2.0m·s-1、1.0m·s-1、0.4m·s-1、0.0m·s-1风速下风速气象因子对苋菜蒸腾耗水及生长的影响。结果表明:温室内盆栽苋菜的蒸腾速率及日蒸腾量受不同风速影响的表现相似,差异不显著,整体看来,蒸腾速率和日蒸腾量以1.0m·s-1风速处理最大,0.4m·s-1风速处理和对照次之,最大风速2.0m·s-1处理最小。采用逐步回归分析了不同风速处理下盆栽苋菜的蒸腾速率、日蒸腾量与气象因子的相关关系,发现不同风速处理蒸腾速率与光照强度的正相关性最强,2.0m·s-1风速处理的蒸腾速率与温度的正相关性次之,而其他处理的蒸腾速率与相对湿度呈显著负相关;日平均温度是影响各处理日蒸腾量的主要因素。盆栽苋菜的物质积累曲线表明,风速1.0m·s-1处理的物质积累量最大,2.0m·s-1处理最小。风速处理对温室盆栽苋菜的地上部鲜重、地下部鲜重以及根冠比均有极显著影响,且1.0m·s-1与2.0m·s-1风速间差异极显著。干物质重受风速影响显著,1.0m·s-1处理干重最大。风速处理对盆栽耗水量和水分利用效率的影响未达显著水平,但1.0m·s-1风速处理的水分利用效率最大。

By using pot experiment under greenhouse condition, the effect of wind speed on amaranth transpiration and biomass accumulation was analyzed at wind speed of 2.0 m·s^-1, 1.0 m·s^-1, 0.4 m·s^-1 and 0.0 m·s^-1. The study shows similar changes in transpiration rate and daily transpiration of potted amaranth at different wind speed. There exist no remarkable differences among the treatments. In general, transpiration rate and daily transpiration are maximum at 1.0 m·s^-1, followed by 0.4 m·s^-1 and the 0.0 m·s^-1, the lowest at 2.0 m·s^-1. Meanwhile, stepwise regression analyses show strongest positive correlation between transpiration rate and illumination intensity under different wind speed, followed by that between transpiration rate and temperature at 2.0 m·s^-1. However, transpiration rate of other treatments has significant negative correlation with relative humidity. Daily mean temperature is a major factor affecting daily transpiration rate. The biomass accumulation curve of the potted amaranth shows that biomass accumulation is highest at 1.0 m·s^-1 and lowest at 2.0 m·s^-1. The effect of wind speed under greenhouse condition on above-ground fresh weight, under-ground fresh weight and root-shoot ratio of potted amaranth are very significant, highest at 1.0 m·s^-1 and lowest at 2.0 m·s-1. Dry matter weight is obviously affected by wind speed, and is maximum at 1.0 m·s^-1. The effect of wind speed on transpiration water consumption and water use efficiency is insignificant, but water use efficiency is maximum at 1.0 m·s^-1 wind speed.