用茎流计研究冬小麦蒸腾规律

Experimental Research on Transpiration of Winter Wheat with Stem Flow Gauge

通过田间试验及理论计算 ,验证了对茎流计在测量作物蒸腾方面的实用价值。试验观测表明 ,白天的作物蒸腾变化与太阳辐射值有很强的相关关系 ,太阳辐射是白天作物蒸腾的主要影响因素 ;作物夜晚的蒸腾变化主要受气温、风速、空气饱和差等因素的影响。通常 ,作物夜晚没有蒸腾 ,但在气温较高 ,风速较大的夜晚 ,作物就会产生很小的蒸腾 ,在天气晴朗的夜晚 。

Stem flow gauge can measure plant flow rate directly. In this paper , we have evaluated the value of the instrument through farmland experiment and theory calculation . The result shows that the change of wheat transpiration has strong correlation with solar radiation in daytime, and the solar radiation is the most important factor in deciding the wheat transpirtion in the day. On the other hand, in nighttime, the transpiration mainly depend on temperature ,windspeed, and saturation vapor pressure,etc. In usual night, there is no transpiration, but if the windspeed and temperature is high enough, winter wheat will have a little transpiration ,and the transpiration changes in a certain regular pattern in clear night.