Isotopic discrimination of zinc in higher plants

Abstract

Summary• The extent of isotopic discrimination of transition metals in biological processes is poorly understood but potentially has important applications in plant and biogeochemical studies.• Using multicollector inductively coupled plasma (ICP) mass spectrometry, we measured isotopic fractionation of zinc (Zn) during uptake from nutrient solutions by rice ( Oryza sativa ), lettuce ( Lactuca sativa ) and tomato ( Lycopersicon esculentum ) plants.• For all three species, the roots showed a similar extent of heavy Zn enrichment relative to the nutrient solution, probably reflecting preferential adsorption on external root surfaces. By contrast, a plant-species specific enrichment of the light Zn isotope occurred in the shoots, indicative of a biological, membrane-transport controlled uptake into plant cells. The extent of the fractionation in the shoots further depended on the Zn speciation in the nutrient solution.• The observed isotopic depletion in heavy Zn from root to shoot ( − 0.13 to − 0.26‰ per atomic mass unit) is equivalent to roughly a quarter of the total reported terrestrial variability of Zn isotopic compositions ( c. 0.84‰ per atomic mass unit). Plant uptake therefore represents an important source of isotopic variation in biogeochemical cycling of Zn.

Cu isotopic compositions in Elsholtzia splendens: Influence of soil condition and growth period on Cu isotopic fractionation in plant tissue

“…This is consistent with previous research that found that lighter Zn and Cu isotopes are partitioned into plants cultivated in solution with a higher metal affinity (Jouvin et al, 2012;Weiss et al, 2005).…”

“…There is now a considerable body of research on heavy metal isotopes in plants, including Fe (Arnold et al, 2015;Guelke and von Blanckenburg, 2007), Cu (Jouvin et al, 2012;Ryan et al, 2013;Weinstein et al, 2011), Zn (Couder et al, 2015;Moynier et al, 2009;Viers et al, 2015, Viers et al, 2007Weiss et al, 2005), Ca (Page et al, 2008), and Mg (Black et al, 2008;Bolou-Bi et al, 2010).…”

Application of Mass Spectrometry for Analysis of Cesium and Strontium in Environmental Samples Obtained in Fukushima Prefecture

“…The isotopic fractionations were observed in some biological processes. For example, the isotopic analysis of Sr [19], Fe [20], and Zn [21] proves that roots are isotopically heavy compared with the aerial parts; the maximum • 87/86 -value was ca. 5.0 for Sr, the maximum • 56/54 -value was ca.…”

13 The Isotope Geochemistry of Zinc and Copper

“…Isotope fractionation induced by higher 377 plants has been found for Zn Moynier et al 2009b). In a pioneering 378 study of isotope fractionation of Zn in the soil-plant system, Weiss et al (2005) found that 379…”