Downward migration of radiocaesium in organic soils across a transect in Scotland

Shand, C. A.; Rosén, Klas; Thored, Kristin; Wendler, Renate; Hillier, S. J.

doi:10.1016/j.jenvrad.2012.08.003

Cited by 17 publications

(12 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, there are also studies suggesting that the 137 Cs behavior in the mineral soil cannot simply be evaluated based on the interaction of 137 Cs with clay minerals and there are many factors that can affect the mobility and bioavailability of 137 Cs in soils. These factors, other than the clay mineralogy, include soil physicochemical properties such as the pH, cation-exchange capacity (CEC), presence of exchangeable cations, organic matter content 9,20–23 , and soil structure 24–26 , soil microbial activities 27–29 , and local climatic and ecological conditions 30–32 .…”

Section: Introductionmentioning

confidence: 99%

A new perspective on the 137Cs retention mechanism in surface soils during the early stage after the Fukushima nuclear accident

Koarashi

Nishimura

Atarashi-Andoh

et al. 2019

Sci Rep

View full text Add to dashboard Cite

The Fukushima Daiichi nuclear power plant accident caused serious radiocesium ( 137 Cs) contamination of the soil in multiple terrestrial ecosystems. Soil is a complex system where minerals, organic matter, and microorganisms interact with each other; therefore, an improved understanding of the interactions of 137 Cs with these soil constituents is key to accurately assessing the environmental consequences of the accident. Soil samples were collected from field, orchard, and forest sites in July 2011, separated into three soil fractions with different mineral–organic interaction characteristics using a density fractionation method, and then analyzed for 137 Cs content, mineral composition, and organic matter content. The results show that 20–71% of the 137 Cs was retained in association with relatively mineral-free, particulate organic matter (POM)-dominant fractions in the orchard and forest surface soil layers. Given the physicochemical and mineralogical properties and the 137 Cs extractability of the soils, 137 Cs incorporation into the complex structure of POM is likely the main mechanism for 137 Cs retention in the surface soil layers. Therefore, our results suggest that a significant fraction of 137 Cs is not immediately immobilized by clay minerals and remains potentially mobile and bioavailable in surface layers of organic-rich soils.

show abstract

Section: Introductionmentioning

confidence: 99%

A new perspective on the 137Cs retention mechanism in surface soils during the early stage after the Fukushima nuclear accident

Koarashi

Nishimura

Atarashi-Andoh

et al. 2019

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Also, several studies have shown that clay mineral composition, mainly an abundance of micaceous clay mineral, has the ability to influence the long-term stabilization of 137 Cs [9,10]. Cesium exists as a univalent cation in solution with small hydration energy, and it is easily adsorbed to negatively charged constituents in soil, especially illitic clay mineral [11]. The strong affinity is supposed to come from the presence of frayed edge sites (FES), which accounts for a minor part of the cation exchange capacity (CEC) of soil clay mineral [6,12].…”

Section: Introductionmentioning

confidence: 99%

“…Several studies have shown that 137 Cs is more easily available to biological systems in organic matter-rich soils [13,14]. However, the adsorption of 137 Cs to organic matter is determined by its concentration in relation to other competing cations and the cation exchange capacity (CEC) of the specific organic substance [11,15]. Organic matter has a smaller affinity for 137 Cs in comparison to clay minerals, and the extent of adsorption is thus limited due to its low selectivity for 137 Cs [11,16].…”

Section: Introductionmentioning

confidence: 99%

“…However, the adsorption of 137 Cs to organic matter is determined by its concentration in relation to other competing cations and the cation exchange capacity (CEC) of the specific organic substance [11,15]. Organic matter has a smaller affinity for 137 Cs in comparison to clay minerals, and the extent of adsorption is thus limited due to its low selectivity for 137 Cs [11,16]. According to Dumat et al [12], either clay minerals prevent Cs adsorption to organic matter, or the binding of Cs to organic matter is so weak that it is easily reversible.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Influence of Soil Characteristics and Land Use Type on Existing Fractions of Radioactive 137Cs in Fukushima Soils

Mensah

Terasaki

Aung³

et al. 2020

Environments

View full text Add to dashboard Cite

Radioactive cesium (137Cs) in distinct soil fractions provides key information to its bioavailability, and therefore determining the effect of soil characteristics and land use types on existing fractions of 137Cs in soils is important for predicting future 137Cs mobility in Fukushima. Thus, the objective of this study was to investigate the influence of soil characteristics and land use types on sequentially extracted fractions of 137Cs in Fukushima. In this study, five coniferous forest soils, eight arable soils, and eight paddy rice soils were sampled in 2012 and 2013. The 137Cs in the soils were separated into four fractions; water-soluble, exchangeable, organic matter-bound and residual fractions. More than 90% of the soil 137Cs fraction for arable and paddy rice soils was found in the residual fraction, implying significantly reduced bioavailable 137Cs with higher fixation. In contrast, forest soils measured higher exchangeable and organic matter-bound fractions of 5%–33% and 9%–44%, respectively, implying future 137Cs mobility in the forest ecosystem. Correlation analysis showed a significant negative correlation (p < 0.05) between the organic matter fraction and residual fraction in both arable and paddy rice soils. There was a significant positive correlation (p < 0.05) for both exchangeable and residual fractions with cation exchange capacity (CEC), total carbon (TC) and total nitrogen (TN) values in arable soils. Organic matter content influenced both exchangeable and residual fractions. It was not clear whether organic matter played a direct role in 137Cs fixation or mobility in the agricultural soils. In paddy rice soils, the organic matter fraction showed a significant negative correlation with TC and TN values. Soil pH was significantly negatively correlated (p < 0.05) with both water-soluble and residual fractions in forest soils but positively (p < 0.1) with the organically bound 137Cs fraction.

show abstract

“…Since roots of fruit trees grow below 3 cm, there was concern that if RCs migrated further down in the soil profile, they may eventually enter the rooting zone of the trees, resulting in enhancement of their RCs uptake from the soil. Studies after the Chernobyl accident revealed that the rate of downward RCs migration in soil varies with soil type (Arapis et al, 1997;Rosén et al, 1999;Schimmack et al, 1989Schimmack et al, , 1997Shand et al, 2013), texture and physicochemical properties (Forsberg and Strandmark, 2001;International Atomic Energy Agency, 2010;Niesiobędzka, 2000;Strebl et al, 1996;Zygmunt et al, 1998), and with rainfall (Schimmack et al, 1994;Shiozawa, 2013). In recent years, both mineral clay (Cremers et al, 1988;Tsukada et al, 2008) and organic matter (Niesiobędzka, 2000;Shand et al, 2013) have been identified as factors that affect the accumulation and migration of RCs in soil.…”

Section: Introductionmentioning

confidence: 99%

Vertical Migration of <sup>137</sup>Cs in Japanese Orchards after the Fukushima Daiichi Nuclear Power Plant Accident

et al. 2019

View full text Add to dashboard Cite

We investigated the vertical 137 Cs distribution in soil among five sod culture orchards with different soil textures over six years after 2011, when 137 Cs fallout was released by the Fukushima Daiichi Nuclear Power Plant accident, to confirm the long-term 137 Cs downward-migration into soil. At each orchard, soil cores were collected to a depth of 30 cm and subdivided into intervals of 3 to 9 cm. The 137 Cs within the 3 cm of topsoil decreased from 84-94% during the first 7 months after deposition in 2011 to 41-75% in 2017. From 2012 onward, the vertical 137 Cs profiles in the soils were explained by a two-component negative exponential model composed of a rapid and a slow component with a change of slope at a depth of 6 to 9 cm. It took 4 years after deposition to show a significant difference in the value of the average 137 Cs migration distance (M d ) among the orchards. The speed of 137 Cs migration in the orchards during the 6 years after the accident year was 0.44 to 0.97 cm year −1 based on the M d . There was a significant positive correlation between M d and fine sand content in the 3 cm of topsoil between M d and the ratio of the total carbon content (TC) at a depth of 3 to 6 cm to that in the top 3 cm of soil. Furthermore, the percentage of exchangeable 137 Cs (ex-137 Cs) to 137 Cs at 3 to 6 cm depth increased significantly in proportion to the ratio of TC at 3 to 6 cm depth to TC at 0 to 3 cm depth in soil collected in 2013. These findings indicate that one of the mobile forms of 137 Cs was ex-137 Cs combined with TC and that the fine sand content and TC influenced the 137 Cs downward-migration in the 3 cm of topsoil in the orchard in which organic matter accumulated by sod culture.

show abstract

Downward migration of radiocaesium in organic soils across a transect in Scotland

Cited by 17 publications

References 36 publications

A new perspective on the 137Cs retention mechanism in surface soils during the early stage after the Fukushima nuclear accident

A new perspective on the 137Cs retention mechanism in surface soils during the early stage after the Fukushima nuclear accident

Influence of Soil Characteristics and Land Use Type on Existing Fractions of Radioactive 137Cs in Fukushima Soils

Vertical Migration of <sup>137</sup>Cs in Japanese Orchards after the Fukushima Daiichi Nuclear Power Plant Accident

Contact Info

Product

Resources

About