大型称重式蒸渗仪测定的冬小麦农田的蒸散规律研究

利用大型称重式蒸渗仪实测数据，对冬小麦蒸散耗水规律进行研究。结果表明：1）冬小麦的目蒸散量变化曲线呈单峰型，中午大，早晚小。蒸散量在分蘖期出现小峰值，此后逐渐降低，返青后又不断增大，在孕穗期土壤水分亏缺严重，作物蒸散量增加速率有所下降。2）Penman—Monteith法估算的实际蒸散量比蒸渗仪实测值略高，怛两者的相关...

Study on Evapotranspiration of the Winter Wheat Measured by Large-scale Weighting Lysimeter

The article made use of measured data by large-scale weighting lysimeter to study evapotranspiration processes of the winter wheat. The results are as follows. 1 ） Variations of evapotranspiration were single peak curves. Values were bigger at noon, and smaller in the morning and evening, the evapotranspiration was low at seedling stage, peak value appeared at tillering stage, and then the evapotranspiration slowly decreased, but after turning green the evapotranspiration of winter wheat continued to grow, but the soil was so drought that the evapotranspiration increased slowly at the booting stage. 2） Values estimated by lysimeter Penman-Monteith equation were higher than values estimated by Penman- Monteith equation, but good correlation can be found between them. 3） The most influencing factor to e- vapotranspiration was net radiation followed by air relative humidity, soil temperature, air temperature, 40 cm soil water content, and wind speed in order. Some empirical models were also proposed for estimation of evapotranspiration through regression analysis.