Use of 2 H and 18 O stable isotopes to investigate water sources for different ages of Populus euphratica along the lower Heihe River

Shubao Liu; Yaning Chen; Yapeng Chen; Jonathan M. Friedman; Gonghuan Fan; Jarre Heng A. Hati

doi:10.1007/s11284-015-1270-6

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Use of 2 H and 18 O stable isotopes to investigate water sources for different ages of Populus euphratica along the lower Heihe River

Shubao Liu·Yaning Chen·Yapeng Chen·Jonathan M. Friedman·Gonghuan Fan·Jarre Heng A. Hati

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Abstract

Investigation of the water sources used by trees of different ages is essential to formulate a conservation strategy for the riparian tree, P . euphratica . This study addressed the contributions of different potential water sources to P . euphratica based on levels of stable oxygen and hydrogen isotopes (δ 18 O, δ 2 H) in the xylem of different aged P . euphratica , as well as in soil water and groundwater along the lower Heihe River. We found significant differences in δ 18 O values in the xylem of different aged P . euphratica . Specifically, the δ 18 O values of young, mature and over-mature forests were −5.368(±0.252) &permil;, −6.033(± 0.185) &permil; and −6.924 (± 0.166) &permil;, respectively, reflecting the reliance of older trees on deeper sources of water with a δ 18 O value closer to that of groundwater. Different aged P . euphratica used different water sources, with young forests rarely using groundwater (mean <15 %) and instead primarily relying on soil water from a depth of 0–50 cm (mean >45 %), and mature and over-mature forests using water from deeper than 100 cm derived primarily from groundwater.

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Source-reported bounding extent: 38.81403111409755° to 42.21224516288584° latitude; 98.81103515625° to 102.67822265625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Shubao Liu, Yaning Chen, Yapeng Chen, Jonathan M. Friedman, Gonghuan Fan, Jarre Heng A. Hati. 2015-05-19. Use of 2 H and 18 O stable isotopes to investigate water sources for different ages of Populus euphratica along the lower Heihe River. https://doi.org/10.1007/s11284-015-1270-6

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