Given the critical role of water in rural development, it is essential to quantify water use by various sectors. Reportedly, a significant water loss during the dry monsoon phase is by Eucalyptus trees in the Ethiopian highlands but few quantitative studies have been carried out. In our study in the Fogera plain near Lake Tana, consumptive water use of a small Eucalyptus patch was calculated from the fluctuating diurnal water table observations for two dry monsoon phases. During the dry monsoon phase in 2014, the groundwater table declined linearly at a rate of 2.6 cm d⁻¹ and in 2015 the decline was 2.5 cm d⁻¹. Daily fluctuations in groundwater were around 20 cm. Translating changing groundwater levels in precise evapotranspiration rates was cumbersome because of uncertainty in the value of drainable porosity. We concluded that the evapotranspiration over the small Eucalyptus patch was at a minimum 3.4 mm d⁻¹ but more likely around 10 mm d⁻¹ at the end of the dry phase. The 10 mm d⁻¹ is twice the reference evaporation rate. This is in accordance with advection aridity approach where the actual evaporation of isolated patches with access to groundwater in dry environments can evaporate at twice the reference rate. The current and future extent of Eucalyptus patches and forests need, therefore, be considered in the management of the groundwater resource.

鉴于水在农村发展中的关键作用，必须量化各个部门的用水量。据报道，在干燥的季风阶段，埃塞俄比亚高地的桉树损失了大量的水，但很少进行定量研究。在我们在塔纳湖附近的Fogera平原进行的研究中，从两个干旱的季风阶段的昼夜地下水位波动中计算出了一个小桉树斑块的耗水量。在2014年的干燥季风阶段，地下水位以2.6 cm d ^-1的速度线性下降，而在2015年下降了2.5 cm d ^{-1的速度。}。地下水的每日波动约为20厘米。由于排空孔隙度的不确定性，要用精确的蒸散速率来转换不断变化的地下水位很麻烦。我们得出的结论是，较小的桉树斑块上的蒸散量至少为3.4 mm d ^-1，但在干燥阶段结束时更可能在10 mm d ^-1附近。10mm d ^-1是参考蒸发速率的两倍。这是与对流干旱方法一致的，在这种方法中，在干燥环境中接触地下水的孤立斑块的实际蒸发量可以以参考速率的两倍蒸发。桉树的当前和未来范围 因此，在地下水资源管理中需要考虑斑块和森林。