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Acid deposition is widespread in Japan, but acidification of stream water is rare in forest ecosystems. Bedrock‐derived cations, including those released into the soil by weathering of bedrock minerals, generally act to neutralize acid deposition and flow out into streams. Volcanic ash, which is widespread in Japan, may also release cations and neutralize acids, but the contribution of volcanic‐ash‐derived cations is currently poorly explored. To assess the importance of volcanic ash as a source of base cations, we examined strontium in two catchments underlain by chert bedrock at Mount Amamaki, Japan. Additionally, we obtained comparative data from two sandstone‐bedrock catchments in the same area. We measured 87Sr/86Sr ratios in samples of stream water, bulk precipitation, riverbed rock, and soil from the catchments. We used the 87Sr/86Sr data to analyze the relative contributions of atmospheric deposition, bedrock, and volcanic ash in soil as sources of Sr in the stream waters. We estimated volcanic ash in soil to contribute between 46% and 78% of stream‐water Sr for one chert‐bedrock catchment, and between 0% and 52% for the other. We conclude that volcanic ash in soil is an important source of Sr in stream water. Thus, volcanic ash can act as a source of base cations and hence contribute to the acid‐neutralizing capacity of soil in forest ecosystems in Japan. [ABSTRACT FROM AUTHOR]

Recently, some studies have established the ecological effects of intraspecific variation in phytochemical traits on soil ecosystems. Because plantations comprise a major proportion of forest area in some regions, intraspecific functional variation in plantation tree species is of great importance to forest ecosystems. Intraspecific variation in plantation tree species can result from natural geographical and cultivated variation. A previous study estimated the effects of geographical variation of Cryptomeria japonica, the most dominant plantation tree in Japan. The results showed that the significant consequences for ecosystem processes, such as calcium (Ca) dynamics and community composition of soil invertebrates, vary among the geographical variation of C. japonica. However, no studies have shown the effect of cultivar variation of tree species on the soil invertebrate community through alteration of the availability of nutrients. In this study, we used a common garden where four cultivars of C. japonica (Kumotoshi, Aya, Obi, and Satsumameasa) were planted in separate plots. In these plots, we measured the concentration of nutrients in leaves, litter and roots, strontium isotope ratio (87Sr/86Sr) of leaves. Root activities, exchangeable nutrients in soil, and soil parameters such as soil pH and abundance and composition of soil invertebrates. Our results show that cultivating different varieties of C. japonica may alter the accumulation of Ca in soil and soil pH. Furthermore, the effects of the cultivated varieties of C. japonica shape the abundance and composition of soil invertebrates by altering the soil properties, such as Ca concentration and pH in the soil. [ABSTRACT FROM AUTHOR]

Simple Summary: Examination of strontium:calcium (Sr:Ca) ratios in otolith has elucidated substantial information on the life history of fishes. This study has found that a drastic decline in otolith Sr:Ca ratios, indicated the initiation of metamorphosis from larva to juvenile in a tropical anguillid eel Anguilla marmorata. Based on the criterion, the current study revealed the early life history and recruitment processes of A. marmorata. Furthermore, the larval transportation, dispersion processes and recruitment dynamics to the Pacific coast of A. marmorata are determined by means of the otolith microchemical analysis in combination with abiotic parameters such as oceanic currents. Recent progress in otolith microchemistry especially in strontium:calcium (Sr:Ca) ratios has revealed significant features of life histories in fishes. A catadromous eel, Anguilla marmorata, has the widest distribution among anguillid eels throughout the Indo-Pacific region. However, its dispersal and recruitment mechanisms in the ocean are still unknown. The temporal and spatial variations of early life history characteristics in a tropical anguillid eel A. marmorata were examined by means of otolith Sr:Ca ratios and microstructure to understand the larval transport and recruitment processes to the coasts in the Pacific region. Durations of the larval stage and age at recruitment to the southern part of Japan ranged from 79 to 157 d and 113 to 192, respectively. No significant differences were found between recruitment months in those parameters. The early life characteristics such as larval duration and age at recruitment were constant throughout the recruitment period in the southern part of Japan. The early life history characteristics in combination with the oceanic current regime possibly determine the larval transportation and dispersion processes and further recruitment dynamics to the Pacific coast of A. marmorata. The present study also provides useful information on its biogeographic distribution in the species as determined by otolith Sr:Ca ratios and microstructure. [ABSTRACT FROM AUTHOR]

Recent studies showed the potential of stable isotopes of the macronutrient calcium (δ44/40Ca) and nonessential strontium (δ88/86Sr) as new trophic level indicators in terrestrial vertebrates and marine teleost fishes. In this study, we tested whether similar Ca and Sr isotopic fractionation trends existed in macroinvertebrate‐dominated stream food webs compared to vertebrates despite their physiological differences. We have determined the δ44/40Ca and δ88/86Sr values as well as the 87Sr/86Sr ratios of stream macroinvertebrates and small gobies and their potential metal sources (stream water, periphyton, and terrestrial plant litter) in upper and lower reaches of two streams in the Lake Biwa catchment, central Japan. The 87Sr/86Sr ratios revealed that stonefly nymphs, crustacea, and gobies mostly relied on aquatic Sr sources. Higher 87Sr/86Sr ratios of some crane fly and caddisfly larvae, mayfly, dobsonfly, and dragonfly nymphs indicated greater terrestrial contributions via plant litter. Positive correlations between the δ44/40Ca and δ88/86Sr values implied that similar Ca and Sr sources existed, and that Ca and Sr stable isotopes underwent similar fractionation trends although Sr was not essential. The δ44/40Ca and partly the δ88/86Sr values were positively correlated with Sr/Ca ratios and negatively with δ15N values indicating trophic effects on Ca and Sr stable isotopes. The enrichment of 44Ca and 88Sr in large filter‐feeding caddisfly larvae was a notable exception from these trophic trends. Our data confirm that the trophic 44Ca and 88Sr depletion observed for marine teleost fishes and terrestrial vertebrates also applied to macroinvertebrate‐dominated stream food webs despite their different physiologies indicating that shared mechanisms of Ca and Sr isotopic fractionation may exist at the cellular or molecular level between these taxa. [ABSTRACT FROM AUTHOR]

The effective removal of strontium from polluted water is an emerging issue worldwide, especially in Japan, after the destruction of Fukushima's Daiichi Nuclear Power Plant. In the strontium removal process, statistical optimization of associated factors is needed to reduce the quantity of chemicals and the number of experimental trials. In this study, response surface methodology based on the central composite design was employed for assessing the influence of different factors and their interaction effects on the efficiency of strontium removal. We have considered nanoscale zero-valent iron-zeolite (nZVI-Z) and nano-Fe/Cu zeolite (nFe/Cu-Z) as adsorbents for the effective removal of strontium. The results suggested that the studied three factors such as pH, contact time, and concentration are positively related to the adsorption of strontium. That is, the maximum strontium removal occurred at pH, initial concentration, and contact time of 12, 200 mg L−1, and 30 min, respectively. The experimental maximum strontium adsorption capacity of nZVI-Z and nFe/Cu-Z adsorbents is 32.5 mg/g and 34 mg/g, respectively. The present study also showed that the most statistically significant potential contributor was initial concentration, followed by contact time in the removal process. The study indicated that the interaction effect between contact time and initial concentration was statistically important, suggesting the need for a multi-mechanism technique in the removal phase of strontium. Tόth, Langmuir, Dubinin-Astakhov (D-A), Freundlich, and Hill isotherm models were also fitted with the experimental strontium adsorption data, in which the Tόth model fitted best compared to the other models based on the RMSD and R2. [ABSTRACT FROM AUTHOR]

In this study, the nondestructive differentiation of individual white polyester clothing fibers was accomplished via synchrotron radiation microbeam X‐ray fluorescence (SR‐μ‐XRF) analysis. SR‐μ‐XRF with vertical focusing is a useful nondestructive method for the analysis of a single polyester clothing fiber. Kirkpatrick–Baez (KB) mirror was used to vertically focus 20 keV X‐rays for the analysis of 22 individual white polyester fibers taken from clothing commonly sold in Japan. SR‐μ‐XRF with a vertical focused 2 μm (V) × 300 μm (H) beam was approximately 12.8 times more sensitive than SR‐XRF with an unfocused 300 μm (V) × 300 μm (H) beam for the detection of elements in single fibers. The minimum detection limits (MDLs) of the SR‐μ‐XRF method were 8.15 ppm for Cl and 0.06 ppm for Br. In addition to Ti in TiO2 delustering agents, Zr and Nb impurities in the delustering agents were detected in individual fibers. Sb from a polymerization catalyst and Co from a transesterification catalyst were also detected in individual fibers. Comparing the Ti Kβ/Sb Lα,β and Zr Kα/Nb Kα X‐ray intensity ratios was a useful way to distinguish individual clothing fibers, and 98% of the fibers were differentiated when additional trace elements were used as discrimination indicators. [ABSTRACT FROM AUTHOR]

Strontium/calcium ratios (Sr/Ca) in reef coral skeletons have been used for sea surface temperature (SST) proxy. Because skeletons of reef corals are accumulated throughout more than 100 years, SST records from coral skeletons were important archives to reveal climate mechanisms. Here, we improved the coral Sr/Ca analytical method using an inductively coupled plasma optical emission spectrometer which method has advantages in terms of initial/running cost and analysis time. We checked variations of Sr and Ca sensitivities as increases of Ca concentrations using various wavelengths of Sr and Ca. Our results suggested that sensitivities of Sr/Ca in a range of coral skeletons were modulated by selections of wavelengths and sensitivity changes of Sr and Ca. A combination of Sr(421.5 nm) and Ca(373.6 nm) is stable for the Sr/Ca analysis at a low Ca concentration. A SD of Sr/Ca(421.5/373.6 nm) was 0.006 mmol mol−1 (1σ, n = 40) based on the replicate measurement of the reference material (JCp‐1) using our new method. By applying a Porites colony from Kikai island, Japan, a precision of reconstructed SST was over ± 0.3°C at weekly resolution. [ABSTRACT FROM AUTHOR]

The geochemistry of the calcium carbonates of marine organisms is an excellent proxy for reconstruction of the paleoceanographic history. However, previous studies of hypercalcified demosponges (sclerosponges) are considerably fewer than those of corals, foraminifers, and bivalves. Here, we investigated stable oxygen (δ18O) and carbon (δ13C) isotopes and minor and trace element (Mg, Sr, Ba, Pb, and U) to Ca ratios of 36 living sclerosponges (Astrosclera willeyana) collected from Kume Island in the Ryukyu Islands, southwestern Japan, to evaluate the utility of geochemistry as a paleoenvironmental proxy. The δ18O, δ13C, and Sr/Ca deviations of the coevally precipitated skeleton were extremely small and almost constant at all skeletal portions, strongly suggesting that within-skeletal variations in the chemical components are negligibly small for non-symbiotic sclerosponges. Mean δ18O, δ13C, and Sr/Ca values (N = 36), falling within a quite narrow range, showed no significant evidence for intraspecific (inter-specimen) variations in the sclerosponges. The sclerosponges δ18O and δ13C were consistent with those of the aragonites precipitated in isotopic equilibrium with seawater at the growth site. The sclerosponge Sr/Ca was close to that of inorganically precipitated aragonite, and the estimated partition coefficient of 1.1 (almost unity) is identical to previously reported values for different species (Ceratoporella nicholsoni). Consequently, these results suggest that A. willeyana sclerosponge, having little vital effects on the geochemistry, is a robust indicator of paleocean environments (seawater δ18O, temperature, and dissolved inorganic carbon δ13C). Further, our evaluation study documents that sclerosponges living in deeper ocean environments can support the reconstruction of spatial and vertical paleoceanographic changes in conjunction with coral proxy records. The sclerosponge U/Ca showed little within-skeletal and intraspecific variations, but the heterogeneity and individual difference of the Mg/Ca, Ba/Ca, and Pb/Ca were relatively large, the reasons of which still remain unresolved. [ABSTRACT FROM AUTHOR]

Strontium-90 (90Sr, half-life of 28.8 years) is one of the major fission products released in the Fukushima Daiichi Nuclear Power Plant accident in Japan. Due to the high concentrations of Sr stable isotopes in marine products, an upper limit for 90Sr isotopic abundance in them is of the order of 1 ppb or less. Resonance ionization technique using narrow linewidth lasers is suitable for analysis requiring high elemental and isotopic selectivity. In this study, we have investigated on 689.4 nm - 487.4 nm - 393.8 nm three-step resonance ionization of Sr atoms, where the 90Sr isotope shifts in the second and third transitions were predicted using a King plot approach to evaluate the optical isotopic selectivity. As the first step in measuring real samples, the influence of coexisting elements in seawater was also derived. [ABSTRACT FROM AUTHOR]

For the first time very low values (up to 0.706707) of the ratio 87Sr/86Sr were recorded in the biogenic carbonates of the Omolon massif (Northeast Asia) of the Capitanian age. These results are in good agreement with previously obtained data on limestones in Japan (Kani et al., 2013; 2018). In general, the strontium ratio curve constructed by us repeats the well-known world trend, differing by its somewhat underestimated (by an average of 0.0005–0.0008) values. The Capitanian strontium minimum can be associated with the entry into the ocean of significant amounts of lightweight femic strontium due to a sharp increase in paleospreading. The maximum values of the strontium ratio, obtained from the middle part of the Intomodesma evenicum bivalve Subzone are 0.706986, which corresponds to the lower part of the Changhsingian stage. [ABSTRACT FROM AUTHOR]

The article focuses on the fallout and the rice contamination in Japan. The accumulation shows that the fallout in Japan is normal and the contamination of the 1956 rice harvest by strontium-90 has been found to be rather serious. The Japanese data are in good accordance with the data obtained by other countries in the temperate zone of the northern hemisphere. This indicates that a considerable fraction of strontium-90 has been retained directly on the surfaces of the crops, not absorbed indirectly through the roots. The hazardous elements cesium-137 and plutonium-239 have been also detected in the atmosphere, rainwater, soil and foodstuffs in Japan.

This study introduces an efficient method for determining 90 Sr activity levels in seawater, reducing the processing time to <3 h for 50 L of seawater. The key feature of the proposed method is the chemical separation of 90 Y when it is in equilibrium with 90 Sr, which is achieved by utilizing custom-made sample-loading equipment and an automated radionuclide separation instrument. As a result, the procedure consistently yields a recovery rate > 90 % for 90 Y. Investigations of 90 Sr levels were conducted in the ocean southeast of Jeju Island from November 2021 to January 2023. Owing to the regional ocean circulation, this region was among the first within the Korean Peninsula to experience the impact of the Fukushima-accident-derived radionuclides. Throughout the investigation period, the observed 90 Sr activity concentration ranged from 0.57 to 1.0 Bq m -3 . No distinct temporal variation of 90 Sr was observed in the selected area during the investigation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this study the behaviour of the trace components caesium (Cs) and strontium (Sr) in a fluidized bed municipal waste incineration is investigated. Doped RDF (refuse derived fuel) was combusted and bed and fly ash concentration were measured for varied fuel injection temperatures and doping amounts. The distribution of the trace components was calculated and shows that Cs is mostly transferred to the fly ash fraction. The same was found to a lesser extend for Sr. The influence of both, injection temperature and doping amounts, was mostly inconclusive. The comparison of the distribution with data from grate combustion experiments shows a significantly higher transfer of Cs to the fly ash. This was even more pronounced for Sr and indicates a transfer of Sr mostly by entrainment of coarse particles in the flue gas. The experimental results give an indication for the release behaviour of Cs and Sr in fluidized bed municipal waste incineration and relevant influencing factors. • Combustion of European refused-derived fuel doped with Cs and Sr in laboratory scale bubbling fluidized bed combustor. • Variation of combustion temperature and concentration of Cs and Sr in fuel. • Determination of the distribution of Cs and Sr to the combustion residues. • Comparison of results with literature data from Japan and experimental results of grate furnace. • Indication of main transfer mechanisms of Cs and Sr to fly ash. [ABSTRACT FROM AUTHOR]

A qualitative assessment of groundwater resources is significant in islands that largely depend on individual aquifers. In Okinawa Island, Japan, limestone aquifers are valuable groundwater reservoirs. However, these aquifers are sensitive to contamination due to high permeability in the conduit network. Although human activity has increased in recent decades, there remains insufficient hydrological information to assess the impact of anthropogenic loading on groundwater quality in Okinawa Island. To address this, we analyzed 4 seepage, 16 river, and 14 shallow (<10 m in depth) groundwater samples to obtain baseline chemistry and anthropogenic impact information on groundwater resources in central Nago City, northern Okinawa Island. We divided the region into three landscape units: lowland (<30 m asl), eastern, and western areas. Except for a limited number of water samples collected in the eastern mountain and coastal section of the lowland, the hydrochemistry was characterized by Ca–HCO 3 type, indicating carbonate weathering within limestone-bearing lithology and Quaternary deposits. Divergent water 87Sr/86Sr values (0.707723–0.712102) with lower Sr concentrations (0.1–1.6 μmol/L) in the mountains and convergent values (0.708859–0.709184) with higher Sr concentrations (0.3–17.6 μmol/L) in the lowland suggest that the water–rock interactions in the lowland aquifer composed of Quaternary deposits are mostly responsible for the hydrochemistry of groundwater resources. The local meteoric water line (δD = 6.38 δ18O + 3.36) indicated that the water originates from precipitation, the altitude effect, and evaporation. The δ15N and δ18O in NO 3 − indicated the addition of manure and septic waste in the lowland aquifer. The results imply that detecting source areas of anthropogenic NO 3 − prior to serious groundwater pollution is important (regardless of the NO 3 − concentration), and isotope analyses would aid in developing appropriate action plans to mitigate or prevent future water pollution by NO 3 − in island regions. [Display omitted] • Okinawa Island, Japan, has valuable groundwater reservoirs of limestone aquifers. • Hydrochemistry and anthropogenic input were identified in groundwater of Nago City. • Carbonate weathering in the lowland aquifer mostly determines water chemistry. • Nitrate isotopes indicated anthropogenic NO 3 − input in western mountain and lowland. • The findings provide insights into sustainable water resource management in islands. [ABSTRACT FROM AUTHOR]

Large amounts of radionuclides were released into the ocean during the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. One of the released radionuclides, 90 Sr, tends to accumulate in bone, and could conceivably have long-term negative impacts on fishes. Here, we investigated 90 Sr radioactivity concentrations in the vertebrae of demersal fishes collected off the coast of Fukushima Prefecture in January and July 2014. High 90 Sr radioactivity concentrations were detected in fish collected from central Fukushima (offshore of the FDNPP) and southern Fukushima (offshore of Iwaki City), but were almost hardly detected in northern Fukushima (offshore of Soma City). Additionally, 90 Sr radioactivity concentrations were higher among rays (Okamejei kenojei and Hemitrygon akajei: from 1.1 ± 0.5 to 103.3 ± 15.1 mBq/g Ca) and soles (Cynoglossus joyneri and Paraplagusia japonica: from 18.5 ± 2.8 to 52.8 ± 11.3 mBq/g Ca) than among other species. Vertebral stable Sr/Ca ratios also differed by fish species. Ca concentrations were relatively constant among species, but Sr concentrations were higher among elasmobranchs and soles, indicating that differences in Sr/Ca might be related to differences in 90 Sr accumulation in fish vertebrae., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Published pre-Fukushima food monitoring data from 1963 to 1995 were used to study the long-term presence of Cs and Sr in rice and wheat. Effective half-lives ( T) were calculated for rice (Cs: 5.6 years; Sr: 6.7 years) and wheat (Cs: 3.5 years; Sr: 6.2 years), respectively. In rice, Cs exhibits a longer T because putrefaction processes will lead to the formation of NH ions that are efficient ion exchangers for mineral-adsorbed cesium ions, hence making it more readily available to the plant. Knowledge on the long-term behavior of radiocesium and radiostrontium will be important for Japanese food-safety campaigns after the Fukushima nuclear accident. [ABSTRACT FROM AUTHOR]

The Fukushima Daiichi Nuclear Power Plant accident in March 2011 resulted in the release of large quantities of a long-lived radioactive strontium (i.e. 90 Sr; half-life: 28.8 y) into the coastal areas of Japan. 90 Sr release was dispersed and mixed into the water column, and will eventually be deposited into sediment. Because factors controlling seawater–sediment partitioning in the coastal marine environments are not fully understood, we developed seawater–sediment distribution coefficients, K d (L/kg), for Sr in coastal regions of Japan by means of sediment–water partitioning experiments. 85 Sr was used as a radiotracer and conditions were designed to mimic the environmental systems of the sampling sites as closely as possible. Experimentally determined K d values ( K d-ex ) varied between 0.3 and 3.3 L/kg (mean, 1.4 L/kg), and the variation in K d-ex was attributed to the percentage of Sr in the exchangeable fraction in the sediment. K d-ex values were used, along with the measured concentrations of 88 Sr, a stable naturally occurring Sr isotope in seawater and sediment, to estimate the concentrations of exchangeable Sr in the sediment. Estimates ranged from 2.1 to 24.3 μg/kg, or 1.3–15.7% of the total 88 Sr concentration in the sediment. Significant correlations existed between the estimated concentrations of exchangeable Sr, and the organic matter and the oxide/hydrous oxide contents. When organic contents were greater than 0.38%, Sr binds to organic surface sites more strongly than to the other sites. Results indicate that binding of Sr to the surface of sedimentary particles was influenced by grain size, iron and manganese oxides, and organic matter. Furthermore, the information presented here could be useful to estimate K d values for anthropogenic 90 Sr in sediment in the coastal marine environment. [ABSTRACT FROM AUTHOR]

Abstract: The water-to-organism (whole body) concentration ratio (CRwo-water), which is defined as the ratio of the concentration of a radionuclide in the biota (Bqkg−1 fresh weight) to that in water (BqL−1), has been used in mathematical models for environmental radiation protection. In the present paper, published global fallout 90Sr, 137Cs, 106Ru, 144Ce and 239+240Pu activity concentration data and stable element concentration data for Na, K, Ca, Mg, Fe, Cu and Mn for organisms living in freshwater or seawater areas in Japan were collated. The data suitable for obtaining CRwo-water values were identified. CRwo-water values of 137Cs were similar for pelagic fish, benthic fish and whitebait (immature, small fish) with respective geometric means of 30 (range: 4.4–69), 32 (range: 15–54) and 33 (range: 13–84). The calculated CRwo-water values of the other radionuclides and stable elements were generally similar to other previously reported values; with the exception that those for Ce were lower for marine biota and those of Cu were higher for freshwater fish. [Copyright &y& Elsevier]

A new method for the determination of radiostrontium in large soil samples has been developed at the Savannah River Environmental Laboratory (Aiken, SC, USA) that allows rapid preconcentration and separation of strontium in large soil samples for the measurement of strontium isotopes by gas flow proportional counting. The need for rapid analyses in the event of a radiological dispersive device or improvised nuclear device event is well-known. In addition, the recent accident at Fukushima Nuclear Power Plant in March, 2011 reinforces the need to have rapid analyses for radionuclides in environmental samples in the event of a nuclear accident. The method employs a novel pre-concentration step that utilizes an iron hydroxide precipitation (enhanced with calcium phosphate) followed by a final calcium fluoride precipitation to remove silicates and other matrix components. The pre-concentration steps, in combination with a rapid Sr Resin separation using vacuum box technology, allow very large soil samples to be analyzed for Sr using gas flow proportional counting with a lower method detection limit. The calcium fluoride precipitation eliminates column flow problems typically associated with large amounts of silicates in large soil samples. [ABSTRACT FROM AUTHOR]

Acoustic telemetry and microchemical analysis of otolith strontium-calcium ratios were used to evaluate how exotic brown trout Salmo trutta have responded to Japanese riverine environments of south-western Hokkaido by observing their migratory patterns. The existence of anadromous S. trutta was also verified. Most S. trutta caught in rivers for otolith analysis were freshwater residents (95·6%), whereas those caught in the sea were mainly smolts (91·3%), which had just migrated from rivers during spring. Anadromous S. trutta ( n = 6) were captured in rivers and in the sea, confirming the existence of mature pre- and post-spawning fish. According to telemetry results, both mature and immature S. trutta used the river in winter, and their estimated sea-run timings showed individual differences. Through the combination of these two methods, migratory patterns on various spatio-temporal scales were observed. This first documentation of the presence of both male and female anadromous S. trutta in the same region within Japan indicated the risk of further colonization of exotic S. trutta via oceanic migration. [ABSTRACT FROM AUTHOR]

Tsunagawa T, Arai T. Migratory history of the freshwater goby Rhinogobius sp. CB in Japan. Ecology of Freshwater Fish 2011: 20: 33-41. © 2010 John Wiley & Sons A/S The migratory histories of Rhinogobius sp. CB collected from 32 locations connected to the sea were studied by examining the strontium (Sr) and calcium (Ca) concentrations in the otoliths using X-ray electron microprobe (EPMA) analysis. The Sr and Ca contents in the riverine water were also determined using inductively coupled plasma mass spectrometry (ICP-MS) analysis. The Sr:Ca ratios in the riverine waters were highly different among rivers and correlated with those in the otolith outer region corresponding to the river life period. Consequently, almost all samples (159 of 160 individuals) showed a typical amphidromous life history, with one individual showing a landlocked life history. These results suggest that the clear differences of migration history in population or locality were not found in Rhinogobius sp. CB. Therefore, it was thought that Rhinogobius sp. CB most commonly had an amphidromous life history. [ABSTRACT FROM AUTHOR]

Abstract  The genetic diversity and relationship among four morphotypes of Rhinogobius sp. OR, Gobiidae (“Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire”) were investigated with seven microsatellite DNA loci, and amphidromy of these morphotypes was verified by strontium (Sr) and calcium (Ca) deposition in the otolith. Samples of “Tōshoku,” “Shinjiko,” “Gi-tōshoku,” and “Shimahire” were collected from, respectively, three, three, two, and four locations in Japan. Microsatellite analysis detected high genetic diversity (based on the number of alleles, allelic richness, and average observed heterozygosity) in the “Tōshoku” and “Shinjiko” morphotypes relative to the “Shimahire” morphotype; the “Gi-tōshoku” morphotype had an intermediate level of variation. Almost all pairwise F ST values were significantly different from zero (P  [ABSTRACT FROM AUTHOR]

In this work, soil-soil solution distribution coefficients ( K d) of Sr and Cs were obtained for 112 Japanese agricultural soil samples (50 paddy soil and 62 upland soil samples) using batch sorption test. The relationships between Sr-or Cs- K d values and soil properties were discussed. Furthermore, the amount of Cs fixed in soil was estimated for 22 selected soil samples using a sequential extraction method. Then, cross effects of some soil properties for Cs fixation were evaluated. [ABSTRACT FROM AUTHOR]

Abstract: Sulfur and strontium isotopes (δ 34S and 87Sr/86Sr) were determined in 39 river water samples collected over three different cultivation periods (April, May, and June), and in several materials used for comparison (fertilizers, detergents, soils, irrigation and agricultural waters), to evaluate the impact of fertilizers on a small agricultural watershed of Lake Biwa, in central Japan. δ 34S values in river water decreased (from +5.8 to −2.0‰) with increasing SO4 concentrations (3.8 to 93.2 ppm) from upstream to downstream of the watershed. Comparison of river water S isotopes with those of possible source materials indicates that the enrichment of SO4 can be attributed to the dissolution of two kinds of fertilizers: (1) compound fertilizers commonly used in this area and (2) ammonium sulfate which is applied on a small scale. In contrast, 87Sr/86Sr values of river water decreased with time from April (avg. 0.71163), through May (avg. 0.71139), to June (avg. 0.71127). The tendency of the sample plots on the 87Sr/86Sr vs. 1/Sr diagram suggests a time-dependent increase in the contribution of soil water to the river, which is partly affected by the Sr-bearing fertilizers. It is suggested that a maximum of 25% of dissolved Sr is derived from these fertilizers, while more than 75% of it is of rock origin. Mass balance calculations permitted us to evaluate the proportion of fertilizer contribution in each river. Combined use of S and Sr isotopes together with concentration data could be a new environmental diagnosis technique for rivers and soils in localized watersheds. [Copyright &y& Elsevier]

Cedar sample was collected at the black rain area in Nagasaki city. A clear peak of 90Sr/Sr was observed in the 1924-1925 rings. To investigate the mobility of Sr in a cedar tree stem, strontium chloride solution was injected into a living tree, and the distribution profiles of Sr in the stem at 8 months later were determined. The strontium moves radially through the sapwood of a cedar stem but that it almost stops at the heartwood. It was concluded that the peak in the 1924-1925 rings was due to the black rain from the Nagasaki atomic bomb. [ABSTRACT FROM AUTHOR]

Neodymium, Sr and Pb isotopic compositions, along with rare earth element (REE) concentrations were determined for twelve black ores and one yellow ore from twelve localities of the Kuroko deposits, Japan. The ores were generated by submarine hydrothermal activity during the Miocene age. Neodymium isotopic compositions of the ores (ɛNd: −4.9 to +6.5) mostly overlap with spatially associated igneous rocks. On a Nd versus Sr isotopic correlation diagram, however,87Sr/86Sr ratios are shifted from the associated igneous rocks towards the higher contemporaneous seawater ratio. REE patterns are highly variable, ranging from light REE enriched to depleted, and show no Ce anomalies, as would be expected if they were derived from seawater. These results suggest that the REEs contained in ores were mainly derived from the associated igneous rocks, but that the ore Sr is a mixture derived from both seawater and the igneous rocks. Most Pb isotopic compositions fall within the range defined by the associated igneous rocks (206Pb/204Pb=18.35–18.84,207Pb/204Pb=15.59–15.97 and208Pb/204Pb=38.53–39.90), although several samples have very radiogenic compositions that were most likely derived from basement rocks. Our new Pb isotopic results display greater variation, and have a larger range of more radiogenic compositions than has been noted previously for these ores. In addition, the black ore with the most radiogenic Pb isotopic composition also has the least radiogenic Nd isotopic composition. This suggests that at least some of the Pb contained in the ores was derived mainly from older basement rocks. The large positive Eu anomalies for some black ores are consistent with a high-temperature origin for the parental fluids, irrespective of the source rock. The single yellow ore examined, however, has a small negative Eu anomaly, which may indicate derivation from a lower temperature fluid. Previous studies suggested that the Kuroko ores were formed in the presence of organic materials in an anoxic basin. Combined Nd, Sr, Pb and Os isotopic and REE abundance data indicate that multiple sources were involved in the genesis of Kuroko ores. [ABSTRACT FROM AUTHOR]

In order to examine the variation in migratory history of the Japanese eel, Anguilla japonica, we measured otolith strontium (Sr) and calcium (Ca) concentrations by X-ray electron microprobe analysis in 5 yellow eels and 20 silver eels collected in the coastal waters of the Amakusa Islands during the spawning migration season. Three migratory types categorized as river eels, estuarine eels and sea eels were found. Estuarine eels were dominant (52%), sea eels were the second most abundant (28%), followed by river eels (20%). The low proportion of river eels from the spawning migration season suggested that the estuarine and sea eels that inhabit the nearby coastal areas might make a larger reproductive contribution to the next generation in this area, although similar analyses should be made over the wide-range geographic distribution of this species, to provide better estimates of the reproductive contributions by different migratory patterns of the population. [ABSTRACT FROM AUTHOR]

Atmospheric aerosols have been collected at four sites around Japan during 2000. From systematically monitoring the major (Na, Mg, Al, K, Ca, and Fe) and trace (Rb and Sr) elements, along with the Sr isotope composition, we have tried to estimate the contribution of long-range-transported Asian dust (“Kosa”) to the atmospheric aerosols.The results are summarized as follows:(1) The concentration of each element in the aerosols increased during the “Kosa” period. The increase was particularly obvious in samples collected on 8 April 2000, when the “Kosa Phenomenon” was observed at all the sampling sites in Japan, 2 days after a very heavy dust storm had occurred in China.(2) The Rb–Sr isotopic diagram shows a two-component mixing relationship: one with a high 87Sr/86Sr ratio and a high 87Rb/86Sr ratio, and the other with a low 87Sr/86Sr ratio and a low 87Rb/86Sr ratio. There is a significant difference between that of the expected end member of the Asian dust and that of the reported Asian loess, which is thought to be the possible source of the components of the “Kosa”, although the lower component is consistent with the local component at Wako.(3) Plots of the 87Sr/86Sr ratio vs the Ca/Al and Sr/Al ratios support a two-component mixing suggested by the Rb–Sr systematics, and they indicate that the contributing continental soil components to the “Kosa” aerosols should be composed of the silicate fraction of Asian loess.(4) The discrepancy in the Rb–Sr systematics between the expected end member and the possible sources may be caused by the dissolution of the Ca-bearing minerals via long-range dust transport, or by a combination of source characteristics and grain size separation. [Copyright &y& Elsevier]

Tests the suitability of tree rings for detecting or assessing local strontium and calcium fallout in Japan. Use of gymnosperm and angiosperm tree species from the vicinity of the atomic bomb hypocenter in Hiroshima; Distinction between residual strontium activity from the Hiroshima atomic bomb and the atmospheric nuclear testing; Geographical variation of strontium-90/strontium level.

Anadromous and resident forms of pond smelt, Hypomesus nipponensis, were found to occur in sympatry in Lake Ogawara, Japan. Profiles of Sr: Ca ratios from individuals could be grouped to two patterns (1) a ‘resident’ pattern with low Sr: Ca ratios from core to edge and (2) an ‘anadromous’ pattern with relatively low Sr: Ca ratios near the core with abrupt increases in ratios at a location approximately 0.3 mm from the core. Spawners smaller than 60 mm standard length (SL) were resident, between 60 to 80 mm were mixed resident and anadromous, and larger than 80 mm were anadromous. Anadromous individuals first migrated after 40 to 82 days from hatching (mean±sd, 59.1±13.5 d) and 14.6 to 30.9 mm SL (22.2±5.3 mm). There was no difference in SL between resident and anadromous individuals during age at first migration, suggesting that size may not be the mechanism for divergence of alternative life history styles. [ABSTRACT FROM AUTHOR]

• Thermal expansion in Al 4 Sr is highly anisotropic by almost a factor to two. • Brittleness of Al-10Sr and derived alloys is due to large thermal expansion mismatch. • Crystal structure of Al 4 Sr reveals lattice parameters and Wyckoff positions. • Second order thermal expansion of Al has been verified at high temperature. • Data analysis is demonstrated on in-situ time-of-flight neutron diffractograms. Photograph of the dilatometer furnace for in-situ neutron scattering at the Takumi beamline, J-PARC, Japan, superimposed by insights into a Williamson-Hall plot (left) and crystal structure of Al 4 Sr (right). [Display omitted] The aluminium strontium master alloy Al-10Sr has been investigated by in-situ neutron diffraction upon a heating-cooling cycle, revealing composition, crystallographic structure, lattice evolution and linear thermal expansion coefficients. Expansion of the Al matrix between [23.5 ... 26.7]·10−6 K−1 depends on temperature and fits well to the literature values, extrapolating to higher temperature at 800 K. Thermal expansion is highly anisotropic for tetragonal Al 4 Sr by a factor of 1.86 with values of 20.8 and 11.1·10−6 K−1 in a and c -axis. The even larger discrepancy to the Al matrix is prone to residual intergranular phase stresses explaining the brittleness of such composite material. Upon first heating, recovery of the initially plastically deformed material is observed until 600 K and 700 K, for Al 4 Sr and Al. Rietveld analysis refines the 4e Wyckoff positions of the I 4/ m m m crystal structure to z = 0.39 revealing that local tetrahedrons are regular while local hexagons are stretched, in contrast to literature. Its lattice parameters report to a I = 4.44240(48) Å, c I = 11.0836(15) Å at 300 K. Furthermore, the manuscript demonstrates full technical analysis of the neutron data. Findings feed into data bases and an outlook for improving mechanical properties of Al 4 Sr composites is given. [ABSTRACT FROM AUTHOR]

In this work, hydrothermal leaching was applied to simulated soils (clay minerals vermiculite, montmorillonite, and kaolinite) and actual soils (Terunuma, Japan) to generate organic acids with the objective to develop an additive-free screening method for determination of Sr in soil. Stable strontium (SrCl 2 ) was adsorbed onto soils for the study, and ten organic acids (citric, L(+)-tartaric, succinic, oxalic, pyruvic, formic, glycolic, lactic, acetic, and propionic) were evaluated for leaching Sr from simulated soils under hydrothermal conditions (120 °C to 200 °C) at concentrations up to 0.3 M. For strontium-adsorbed vermiculite (Sr-V), 0.1 M citric acid was found to be effective for leaching Sr at 150 °C and 1 h treatment time. Based on these results, the formation of organic acids from organic matter in Terunuma soil was studied. Hydrothermal treatment of Terunuma soil produced a maximum amount of organic acids at 200 °C and 0.5 h reaction time. To confirm the possibility for leaching of Sr from Terunuma soil, strontium-adsorbed Terunuma soil (Sr-S) was studied. For Sr-S, hydrothermal treatment at 200 °C for 0.5 h reaction time allowed 40% of the Sr to be leached at room temperature, thus demonstrating an additive-free method for screening of Sr in soil. The additive-free hydrothermal leaching method avoids calcination of solids in the first step of chemical analysis and has application to both routine monitoring of metals in soils and to emergency situations., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The article provides information on the study which examines the calcium (Ca) and strontium (Sr) distribution in the Japanese anchovy otoliths and the possible limitations of the Sr:Ca ratio for migration studies. It has been indicated that Ca concentration was relatively constant throughout the otolith. On the other hand, the Sr concentrations markedly changed along the lifehistory division. It has been suggested by the researchers that increase Sr:Ca ratios during the metamorphosis stage may be connected to high stress.

Strontium (Sr) and calcium (Ca) concentrations in the otoliths of the shirauo, Salangichthys microdon, collected from Japanese coastal waters were examined by wavelength-dispersive X-ray spectrometry on an electron microprobe. The otolith Sr : Ca ratios gradually increased from 15.7−19.7 × 10−3 around the core to 32.8−39.4 × 10−3 around the edge of otoliths, with no transition point from the low Sr : Ca ratio phase to the high phase. The fluctuation pattern of otolith Sr : Ca ratios was different from the anadromous form reported in a previous study. The evidence indicates that the fish do not necessarily migrate into freshwater during the growth phase. [ABSTRACT FROM AUTHOR]

The fate of strontium-90 ( 90 Sr) from water to aquatic biota is of concern since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident because of continuous small 90 Sr releases to the seawater from the FDNPP site. The Japanese diet includes many edible marine and freshwater species, and the environmental parameter, that is, the concentration ratio (CR) from water to biota, is useful to estimate the potential 90 Sr intake, especially from frequently consumed seafoods. However, widely used CR data for radiation dose assessment only have provided values for biota types such as fish, crustaceans, macroalgae, and so forth, and thus, it is difficult to identify specific data for each species. In this study, therefore, we collated CR data of Sr for aquatic biota by surveying available open data sources from the 1950s to 2019, not only for edible parts but also for whole and inedible parts. In total, we obtained 3800 CR data: 3013 data for marine biota, 28 data for brackish water biota, and 759 data for freshwater biota. The results showed that species-specific CRs may decrease the uncertainties compared to those published in IAEA documents; however, different diets and living areas by species may lead to different uncertainties for different species.

Stable carbon (δ13C) and oxygen isotope (δ18O) compositions of fossil brachiopod shells can be used to interpret paleoclimatic and paleoceanographic conditions. However, the initial isotopic composition of the living shells might be modified by diagenetic alteration. To assess the degree of this modification, we analyzed δ13C and δ18O and three common indicators of alteration in shells: minor element (manganese (Mn), iron (Fe), and strontium (Sr)) concentrations; cathodoluminescence (CL)/non-luminescence; and the shell microstructure of fossil Terebratalia coreanica and Laqueus rubellus (rhynchonellate brachiopod) shells from an exposure of conglomerates of the Tentokuji Formation (Pliocene, 3.85–2.75 Ma) in northeastern Japan. Two indices were used to quantify the preservation state of shell microstructure: the altered fiber ratio (AFR) and the altered fiber and puncta-filling cement ratio (AF-PCR). We qualified the degree of luminescence by measuring the mean cathodoluminescence index (MCLI), defined as the mean R values in a particular area of a CL image with RGB colors. The δ13C and δ18O values were negatively correlated with AFR or AF-PCR and MCLI. The sampling spots with high Mn and Fe concentrations also exhibited relatively low δ13C and δ18O. The δ13C and δ18O were more strongly correlated with Mn concentration than with Fe concentration. Therefore, of the three minor elements examined in this study, Mn concentration is the most reliable indicator of meteoric diagenesis in the studied shells. Unlike Mn and Fe concentrations, Sr concentrations in the modern and fossil brachiopod shells were similar, with overlapping ranges. This indicates that Sr concentration is not likely to be a good indicator of diagenetic alteration in the studied shells. Our study provides further evidence that multiple criteria should be applied and cross-checked when assessing diagenetic alteration of brachiopod shells. [ABSTRACT FROM AUTHOR]

The radiological releases from the damaged fuel to the atmosphere and into the cooling water in the Fukushima Daiich Nuclear Power Plant (FDNPP) accident are investigated. Atmospheric releases to the land and ocean mostly occurred during the first week after the accident whereas continuous release from the damaged fuel into the cooling water resulted in an accumulation of contaminated water in the plant during last six years. An evaluation of measurement data and analytical model for the release of radionuclides indicated that atmospheric releases were mainly governed by the volatility of the radionuclides. Using the measurement data on the contaminated water, the mechanism for the release of long-lived radionuclides into the cooling water was analyzed. It was found that the radioactivity concentrations of 90 Sr in the contaminated water in the Primary Containment Vessel (PCV) of unit 2 and unit 3 were consistently higher than that of 137 Cs and the radioactivity concentration of 90 Sr in the turbine building of unit 1 in year 2015 was higher than that in year 2011. It was also observed that the radioactivity concentration of long-lived radionuclides in the contaminated water in the FDNPP is still high even in year 2015. The activity ratio of 238 Pu/ 239+240 Pu for the contaminated water was in the range of 1.7-5.4, which was significantly different from the ratios from the soil samples representing the atmospheric releases of FDNPP. It is concluded that the release mechanisms into the atmosphere and cooling water are clearly different and there has been significant amount of long-lived radionuclides released into the contaminated water., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The water-to-organism (whole body) concentration ratio (CR(wo-water)), which is defined as the ratio of the concentration of a radionuclide in the biota (Bq kg(-1) fresh weight) to that in water (Bq L(-1)), has been used in mathematical models for environmental radiation protection. In the present paper, published global fallout (90)Sr, (137)Cs, (106)Ru, (144)Ce and (239+240)Pu activity concentration data and stable element concentration data for Na, K, Ca, Mg, Fe, Cu and Mn for organisms living in freshwater or seawater areas in Japan were collated. The data suitable for obtaining CR(wo-water) values were identified. CR(wo-water) values of (137)Cs were similar for pelagic fish, benthic fish and whitebait (immature, small fish) with respective geometric means of 30 (range: 4.4-69), 32 (range: 15-54) and 33 (range: 13-84). The calculated CR(wo-water) values of the other radionuclides and stable elements were generally similar to other previously reported values; with the exception that those for Ce were lower for marine biota and those of Cu were higher for freshwater fish., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Radionuclides were widely released into the environment due to the nuclear accident at the Fukushima Daiichi Nuclear Power Plant. Some of these radionuclides have flowed into municipal sewage treatment plants through sewer systems. We have observed the fate of stable Sr in the sewage treatment process as a means to predict the fate of radiostrontium. Concentrations of stable Sr were determined in sewage influent, effluent, dewatered sludge, and incinerated sewage sludge ash collected from a sewage treatment plant once a month from July to December 2011. In the mass balance of Sr in the sewage treatment plant, 76% of the Sr entering the plant was discharged to the receiving water on average. Additionally, 14% of the Sr flowing through the plant was transferred to the sewage sludge and then concentrated in the sludge ash without being released to the atmosphere. We also investigated Sr sorption by activated sludge in a batch experiment. Measurements at 3 and 6h after the contact showed Sr was sorbed in the activated sludge; however, the measurements indicated Sr desorption from activated sludge occurred 48 h after the contact., (Copyright © 2013 Elsevier B.V. All rights reserved.)