干旱气候条件下石膏板小区法海滩幼龄白蜡林水分消耗量评价

 在奥地利东部深厚的黄土区,利用石膏板小区法,通过测量土壤水分平衡,对生长在海滩的幼龄白蜡水青冈树混交林的蒸散量进行了估算,发现在200 0年4月到2004年3月观察期间,幼龄白蜡林的年实际蒸散量达712mm/a,消耗了所有644mm年降雨量以及268mm的土壤储水量,并且没有明显深层渗漏。在根部土壤剖面平均土壤水吸力小于0.4MPa状况下,主要生长季节(6月到9月)的彭曼公式作物系数为1.4,同时发现,当根部土壤剖面平均土壤水吸力为1.7MPa时,该系数会线性递减至0.2。

Assessment of Water Consumption of a Young Ash Tree-white Beech Plantation in a Dry Climate by Gypsum Block Method

The actual evapotranspiration of a young ash tree-white beech plantation on a deep loess soil in Eastern Austria was estimated from measurements of the soil water balance using the gypsum block method. During the observation period from April 2000 to March 2004 the yearly actual evapotranspiration of the plantation amounted to 712mm/a, thus consuming all the precipitation of 644mm plus 268mm of the soil water storage. There was effective no deep percolation. The crop coefficient Kc of the FAO Penman-Monteith formula for the main growing season (June to September) was estimated to be 1.4 for a mean soil water suction within the rooted soil profile less than 0.4MPa and was found to decrease linearly to Kc=0.2 at 1.7MPa.