微型蒸发器长度影响土壤蒸发测量值的试验研究

研究使用了不同长度的不锈钢微型蒸发器测定裸土和冬小麦冠层下的土壤蒸发量。目标是考查不同长度蒸发器测定土壤蒸发量的差异性及原因。试验结果显示,在蒸发强度较低的情况下,不同长度的微型蒸发器测定值之间有很好的相关关系,但数值上存在显著的差异,原因可能是不锈钢导热性高所致;在蒸发率较高的情况下,不同长度微型蒸发器的观测值之间有明显差异,主要原因是不同长度引起的供水差异所致。研究认为,50 mm长度的微型蒸发器在蒸发强度不高的情况下,可以适合裸土和植物冠层下土壤蒸发的日观测。但金属材料可能不是制作微型蒸发器的理想材料。

Effects of Stainless Steel Micro-lysimeter Lengths on Soil Evaporation Measurement

In this research,different lengths of micro-lysimeter were adopted to measure the evaporation from bare soil and soil under winter wheat canopies.The results showed the evaporation recorded from different micro-lysimeters was significantly different.And,the high heat conductivity of steel was the possible reason of the difference.The measured values under the high evaporation rate were great disparity.This was caused by the difference of water supply by different lengths of micro-lysimeter.The 50 mm-length micro-lysimeter could be used in the short-term soil evaporation under low evaporation potential.But,the metal materials may not suitable for micro-lysimeter.