Vol.:(0123456789) 1 3
Environmental Earth Sciences (2020) 79:300
https://doi.org/10.1007/s12665-020-09046-8
ORIGINAL ARTICLE
Strontium isotope composition aided strontium and calcium sourcing
in a cool temperate ecosystem, South Korea
Mukesh Kumar Gautam
1,2
· Kwang‑Sik Lee
1
· Byeong‑Yeol Song
1,3
Received: 22 August 2019 / Accepted: 5 June 2020
© Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract
Atmospheric deposition and mineral weathering are important sources of base cations in vegetated ecosystems. To assess
plant preferences for weathering-fed versus atmospheric-fed mineral nutrition during diferent growth stages (sapling to
mature), we have studied
87
Sr/
86
Sr isotope ratios, and Ca and Sr concentrations in the vegetation, litter, organic matter and
mineral soils from fve functionally diferent species: Korean red pine, Korean chestnut, black locust, annual feabane,
and silvergrass. Isotope values of vegetations (0.7124–0.7162) closely matched with that of litter (0.7143–0.7161), soil
(0.7126–0.7165), and parent material (0.7161). Plant height (as a proxy for maturity) and plant functional forms did not
show discriminating efect on the variation in the Sr isotope ratio. An assessment of the relative contribution of the in-situ
weathering input versus the ex-situ atmospheric input using a mixing equation suggests that vegetation, irrespective of
maturity, is dependent on the weathering supplied elements as a primary source of nutrients. At all the sites, the
87
Sr/
86
Sr
ratio of organic layers and mineral soil were similar to the isotopic values of the vegetation, suggesting an active recycling
pool and suggesting that vegetation in the region conservatively extracts nutrients from weathered parent materials, which
are then internally recycled via organic layers.
Keywords Plant nutrition · Strontium isotope (
87
Sr/
86
Sr) · Strontium · Calcium · Sr/ca ratio (Sr/Ca) · East Asia
Introduction
Atmospheric depositions (wet and dry depositions) and min-
eral weathering are important sources of base cations in veg-
etated ecosystems (Vitousek et al. 1999; Poszwa et al. 2004;
Bélenger and Holmden 2010; Bedel et al. 2016; Noval et al.
2020). Discerning whether base cation biogeochemistry is
dominated by weathering-derived or atmospheric-derived
elements has important implications for (a) nutrient cycling
of essential elements, (b) long-term ability to bufer terres-
trial acidifcation, and (c) temperate ecosystems with highly
weathered soils, constrained base cation supply and critical
load exceedances (Kennedy et al. 1998; Bullen and Bailey
2005; Bern et al. 2005; Dasch et al. 2006; Bedel et al. 2016;
Schmitt et al. 2017).
Among the base cations, calcium is the largest contribu-
tor to soil cation exchange complexes, providing the bulk of
bufering to soil (Gautam and Lee 2016; Johnson and Lind-
berg 2013). Ca provides chemical homeostasis, it is criti-
cal in neutralizing acidic inputs and maintaining the health
of vegetated ecosystems. Given the importance of Ca in
plant processes and vegetated ecosystems, tools to track its
sources, pathways, and bioavailability are essential (Blum
et al. 2008; Bélanger and Holmden 2010). Over the past
century, terrestrial acidifcation and consequent base cation
depletion and mobilization of acidic cations have resulted in
detrimental efects on vegetation health and productivity in
Electronic supplementary material The online version of this
article (https://doi.org/10.1007/s12665-020-09046-8) contains
supplementary material, which is available to authorized users.
* Mukesh Kumar Gautam
mukeshcric@gmail.com
* Kwang-Sik Lee
kslee@kbsi.re.kr
Byeong-Yeol Song
songby23@gmail.com
1
Division of Earth and Environmental Sciences, Korea
Basic Science Institute, Ochang, Chungbuk 363-883,
Republic of Korea
2
Biology Department, Medgar Evers College, University
of New York, New York, NY 11225, USA
3
Chemical Analysis Division, National Forensic Service,
Wonju 220-170, Republic of Korea
Content courtesy of Springer Nature, terms of use apply. Rights reserved.