Stable Oxygen and Deuterium Isotope Techniques to Identify Plant Water Sources

Abstract

There is still very little information on the sources of water absorbed by oil palm plant. This information is very important for water management system in oil palm plantation. Thus, this study was carried out to determine current water sources absorbed by the oil palm roots using oxygen (δ 18 O) and deuterium isotopes (δD) techniques. Sketches of oxygen and deuterium isotope were total rainfall, throughfall, runoff, measurement at 5 soil depths (namely: 20 cm, 50 cm, 100 cm, 150 cm, and 200 cm), and oil palm stem. Results of this study showed huge variance in the values of oxygen and deuterium isotope. Based on Least Significant Difference (LSD) test, there was no significant value in the oxygen and deuterium isotope of stem water and others; however, a similar value was obtained at the depths of 0-20 cm and 20-50 cm with the stem water. This indicated that oil palm absorbed water from 0-50 cm depth. This result agreed with the oil palm rooting system, which has verified that the root quarter is the most active root of oil palm.

A deuterium-based labeling technique for the investigation of rooting depths, water uptake dynamics and unsaturated zone water transport in semiarid environments

“…Other applications of environmental isotopes include the identification of water use strategies of certain species (i.e. Brunel et al, 1995;Chimner and Cooper, 2004;Edwin et al, 2014;Li et al, 2007), changes in water-use strategies (Wu et al, 2013), quantifications of preferential flow (Stumpp and Maloszewski, 2010) and investigations on hydraulic lift (Ceperley et al, 2014). Dawson et al (2007) used measurements of stable isotopes in woody plants to identify nighttime transpiration.…”

“…We used both xylem and transpired water samples for the analysis. Xylem sampling took place only once per day to avoid harm to the trees under investigation, using an increment borer, whereas bags for collecting transpired water (Calder et al, 1986Calder, 1992;Edwin et al, 2014;Lambs and Saenger, 2011;Luvall and Murphy, 1982) were used at least twice per day. The xylem samples were taken at chest height and only suberized stems were sampled (Dawson and Ehleringer, 1993).…”

The Stable Isotope Hydrology of Sable Island, NS, Canada

“…Among biological investigations, the field of hydroecology has been a fundamental addition to studies formally evaluating sources of water to foodwebs (Baxter et al, 2005;Meier-Augenstein, 2011). The use of isotopic measurements of water to establish key ecological information such as plant water uptake (Edwin et al, 2014) and water sources used by animals (Wolf et al, 2002;Vander Zanden et al, 2016) are now well established. More recently, measurements of δ 17 O in environmental waters have been used together with δ 18 O to provide additional information on sources of water and mechanisms of transport related to differential involvement of kinetic vs. equilibrium fractionation (Tian et al, 2021).…”

Water vapor, precipitation and evapotranspiration isotopic composition in the tropical atmospheric boundary layer

“…Depending on the hydrological regime of the area, soil water isotopic composition can change according to the frequency and intensity of precipitation and, in upper soil levels are usually enriched in heavier isotopes due to moisture with the lower boundary layer. However it is important to consider that no fractionation during water uptake by roots occurs (Zimmerman, Ehhalt, and Münnich, 1967;Gat, 1996;Edwin et al, 2014).…”

“…These include effects on the water cycle due to the modification of the local radiative balance (Comte et al, 2012;Merten et al, 2016). However, despite the importance that this plant achieved in recent times, little is known about the isotopic water cycle and about oil palm physiological parameters related to the isotopic composition of transpiration and soil evaporation (Edwin et al, 2014). To our knowledge, values of leaf boundary layer conductance (g bl ) and effective path length (L ef f ) for oil palm do not exist in literature, therefore, in order to provide estimates for these parameters we investigated the water cycle of an oil palm plantation in Indonesia.…”