The isotopic composition of water transmitted by the canopy as throughfall or stemflow reflects a suite of processes modifying rainfall. Factors that affect isotopic composition of canopy water include fractionation, exchange between liquid and vapor, and selective transmittance of temporally varying rainfall along varying canopy flowpaths. Despite frequent attribution of canopy effects on isotopic composition of throughfall to evaporative fractionation, data suggest exchange and selection are more likely the dominant factors. Temporal variability in canopy effects is generally consistent with either exchange or selection, but spatial variability is generally more consistent with selection. However, most investigations to date have not collected data sufficient to unambiguously identify controlling processes. Using isotopic data for improved understanding of physical processes and water routing in the canopy requires recognizing how these factors and processes lead to patterns of isotopic variability, and then applying this understanding toward focused data collection and analysis. WIREs Water 2017, 4:e1187. doi: 10.1002/wat2.1187

中文翻译：

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稳定同位素在理解降雨拦截过程中的作用：综述。

冠层通过穿透水或茎流传输的水的同位素组成反映了一系列改变降雨的过程。影响冠层水同位素组成的因素包括分馏，液体和蒸汽之间的交换以及沿变化的冠层流动路径随时间变化的降雨的选择性透射率。尽管冠层效应对穿透的同位素组成经常归因于蒸发分馏，但数据表明交换和选择更可能是主导因素。冠层效应的时间变异性通常与交换或选择一致，但空间变异性通常与选择更一致。但是，迄今为止，大多数调查还没有收集到足以明确识别控制程序的数据。电线水2017，4：e1187。doi：10.1002 / wat2.1187