Controls on leaf water hydrogen and oxygen isotopes: a local investigation across seasons and altitude

Abstract. The stable oxygen (?18Oleaf) and hydrogen (?2Hleaf) isotopes of leaf water act as a bridge that connects the hydroclimate to plant-derived organic matter. However, it remains unclear whether source (i.e., twig water, soil precipitation) or meteorological parameters temperature, relative humidity, are dominant controls on ?18Oleaf ?2Hleaf. Here, we reported seasonal analysis ?2Hleaf together with from potential waters along an elevation transect Chinese Loess Plateau. We found values were more closely correlated than values, whereas similarly transect. Dual-isotope showed associated because their similar altitudinal responses, generating well-defined isotope line local meteoric (LMWL). also compared measured predicted by Craig–Gordon model no significant differences between them. demonstrate first-order control was second-order enrichment biochemical environmental factors