Progress and challenges in using stable isotopes to trace plant carbon and water relations across scales

Abstract

Abstract. Stable isotope analysis is a powerful tool for assessing plant carbon and water relations and their impact on biogeochemical processes at different scales. Our processbased understanding of stable isotope signals, as well as technological developments, has progressed significantly, opening new frontiers in ecological and interdisciplinary research. This has promoted the broad utilisation of carbon, oxygen and hydrogen isotope applications to gain insight into plant carbon and water cycling and their interaction with the atmosphere and pedosphere. Here, we highlight specific areas of recent progress and new research challenges in plant carbon and water relations, using selected examples covering scales from the leaf to the regional scale. Further, we discuss strengths and limitations of recent technological Published by Copernicus Publications on behalf of the European Geosciences Union. C. Werner et al.: Progress and challenges in using stable isotopesdevelopments and approaches and highlight new opportunities arising from unprecedented temporal and spatial resolution of stable isotope measurements.

Linking plant and ecosystem functional biogeography

“…1A. At the leaf, plant, and ecosystem scale, water-use efficiency (WUE) can be derived from the carbon-isotope signatures δ 13 C of plant tissues (e.g., leaves, tree rings), which integrate WUE from daily to decadal timescales (68,69). For trees, wood density has been found to be an important and well-documented integrative trait related to hydraulic conductivity, leaf traits (including photosynthetic ones), and patterns of water uptake and transpiration (70) and is thus potentially a good proxy for water use and its constraints on the carbon cycle (Fig.…”

Evaluating calibration strategies for isotope ratio infrared spectroscopy for atmospheric <sup>13</sup>CO<sub>2</sub> / <sup>12</sup>CO<sub>2</sub> measurement

“…With proper calibration, it can achieve precision similar to that of isotope ratio mass spectrometry (IRMS) (Kerstel and Gianfrani, 2008;Berryman et al, 2011;Werner et al, 2012). At least five types of IRIS instruments are available for field measurement of δ 13 C, including tunable diode laser absorption spectroscopy (Campbell Scientific Inc., Logan, UT; e.g., Bowling et al, 2003;Griffis et al, 2008;Wingate et al, 2010;Santos et al, 2012), quantum cascade laser absorption spectroscopy (Aerodyne Research, Inc., Billerica, MA; e.g., Wada et al, 2011;Kammer et al, 2011;Sturm et al, 2012), wavelength-scanned cavity ring-down spectroscopy (Picarro Inc., Sunnyvale, CA; e.g., Friedrichs et al, 2010;Bai et al, 2011;Berryman et al, 2011), off-axis integrated cavity output spectroscopy (Los Gatos Research, Mountain View, CA;e.g., McAlexander et al, 2011;Guillon et al, 2012), and Fourier transform infrared spectroscopy (e.g., Mohn et al, 2008;Griffith et al, 2012;Hammer et al, 2013).…”

“…All the IRIS instruments should maintain accuracy traceable to the international PDB-CO 2 or VPDB-CO 2 scale. However, in comparison to IRMS, whose operational procedures are mature, IRIS is a relatively immature technology still subject to a number of artifacts some users may not be fully aware of (Griffith et al, 2012;Werner et al, 2012). Sensitivity to changing environmental conditions (e.g., temperature dependence; Guillon et al, 2012) and dependence of δ 13 C on CO 2 concentration are the two main sources of error affecting the IRIS measurements (Wada et al, 2011;McAlexander et al, 2011;Guillon et al, 2012).…”

Stable Isotopic Analysis on Water Utilization of Two Xerophytic Shrubs in a Revegetated Desert Area: Tengger Desert, China

“…Stable isotopes and their potential application for detecting various and complex ecosystem processes are gaining the interest of an increasing number of scientists [8][9][10]. Stable isotopes are powerful tools for detecting water movement along the soil plant-atmosphere continuum system [11,12].…”