The link between rainfall and groundwater recharge in the Rio del Rey Basin, which is of socio-economic importance to Cameroon, is poorly understood. Accordingly, the stable isotopes in monthly rainfall from January to December 2012 (in Lobe and Mundemba) and 52 surface water and groundwater samples were investigated. High values of δ¹⁸O and δD were recorded in the dry period (February to March), and the least values of δ¹⁸O and δD were observed in the wet period (September). This indicates that different condensation processes primarily influenced stable isotopes in rainfall as a function of the difference in moisture sources. The relationship between δD and δ¹⁸O defined the Lobe meteoric water line as δD = 7.97 δ¹⁸O + 12.48 and Mundemba water line as δD = 7.75 δ¹⁸O + 10.79. The similarity of their slopes to the global meteoric line suggests that the isotopic composition of investigated rains was not significantly affected by evaporation during precipitation. The ranges in deuterium-excess of precipitation from 5.8 to 16.56‰ suggest the source of vapour is from the Atlantic Ocean. The groundwater isotope values (ranging from −3.81 to −2.52‰ for δ¹⁸O) plotted close to and along the GMWL, showing that its isotopic composition is of meteoric origin under rapid recharge conditions. The isotopic similarity between groundwater and June–August rains suggests a significant recharge during this period.

对喀麦隆具有社会经济重要性的 Rio del Rey 盆地降雨与地下水补给之间的联系知之甚少。因此，研究了 2012 年 1 月至 12 月（在 Lobe 和 Mundemba）的月降雨量和 52 个地表水和地下水样品中的稳定同位素。δ ¹⁸ O 和 δD 在干旱期（2 月至 3 月）录得较高值，而在湿润期（9 月）观测到δ ¹⁸ O 和 δD值最低。这表明不同的凝结过程主要影响降雨中的稳定同位素，这是水分来源差异的函数。δD 与 δ ¹⁸ O之间的关系将 Lobe 大气水线定义为 δD = 7.97 δ ¹⁸O + 12.48 和 Mundemba 水线为 δD = 7.75 δ ¹⁸ O + 10.79。它们的坡度与全球陨石线的相似性表明，调查的降雨的同位素组成不受降水过程中蒸发的显着影响。从 5.8 到 16.56‰ 的氘过量降水范围表明蒸汽的来源来自大西洋。地下水同位素值（δ ¹⁸ O 的范围从 -3.81 到 -2.52‰ ）靠近并沿着 GMWL 绘制，表明其同位素组成在快速补给条件下来自大气。地下水与 6 月至 8 月降雨之间的同位素相似性表明在此期间进行了大量补给。