This study explores previously unreported linkage between recession rates of rainfall hyetograph and river flow hydrograph in an arid environment in Sultanate of Oman. Ephemeral streams are hydraulically disconnected from groundwater aquifers and depend on rainfall to produce water that flows only for hours or a few days at most. It therefore prompted to hypothesize that the recession rate of the rainfall event controls the corresponding recession of river flow. To test this assumption, 1-h river flow rates and 20-min rainfall rates in Al-Khoud catchment area for the period 1997–2013 were analysed. The river flow recession rate and antecedent river flow were found to be inversely proportional, while their relation improved with increasing time span of cumulating the antecedent river flow. The results further show that the simulation of river flow recession rate can be improved by incorporating the combined effects of rainfall recession rate and antecedent moisture content.

这项研究探索了阿曼苏丹国干旱环境中雨水记录仪和河流流量水位仪的衰退率之间未曾报道的联系。暂时的水流与地下水含水层在水力上断开连接，并依靠降雨来产生最多只能流动数小时或数天的水。因此，它提示人们假设降雨事件的衰退率控制着相应的河流流量衰退。为了检验这一假设，分析了1997-2013年Al-Khoud集水区的1-h河流流量和20-min降雨率。发现河流退水率与前期河流流量成反比，但它们的关系随着前期河流流量累积时间的增加而改善。