Background levels of trace and ultra-trace elements in soils of Japan

Abstract

Five hundred and fourteen soil samples collected from 78 sites in Japan were analyzed for their contents of trace and ultra-trace elements. We estimated the background levels (natural abundance) of 57 elements in soils. The concentration ranges were so wide that the ratios of the highest values to the lowest values were more than 100 for all the elements, with the exception of Be, Ga, Mo, Ag, In, Sn, and Ba. While the concentrations of the first transition elements (2ISC to soZn in atomic numbers) were higher than the concentration of the other elements, those of lighter (sLi and 4Be) and heavier elements tended to decrease, with an increase or decrease of atomic numbers, with the apparent exception of Pb, Th, and U. Concentrations of elements with even atomic numbers were, in most of the cases, higher than the concentrations of both adjacent elements with odd atomic numbers. Frequency distribution of most of the elements was strongly positively skewed. Markedly positive correlation coefficients (r>0.9) were observed among the elements within the same group in the Periodic Table in many combinations. The dendrogram obtained by cluster analysis showed that the occurrence and distribution of the elements in soils were mostly controlled by the chemical properties of each element, rather than by the nature and properties of individual soil samples. The total contents of the elements in soils were strongly dependent on the chemical composition of the parent rocks from which respective soils were derived.Key Words: background level, trace and ultra-trace elements.Basic information on the background levels, or the natural abundance, of elements in soils is required for studies on the behavior of elements in the soil-plant systems. In recent years, there has been an increasing concern about the concentrations of various trace and ultra-trace elements in environmental samples. In spite of this growing interest and although a total of only 90 elements were involved CH to 92U in atomic numbers, with the exception of the man-made 4S Tc and 6IPr), most of the soil scientists appear to have paid most attention to a limited number of beneficial elements (B, Mn, Fe, Cu, Zn, and Mo) and selected

Systematic geochemical study of the soils, litter, and bedrock of a Permian limestone mountain, Central Japan

“…Kinshozan soils, comparisons with average compositions of Japanese soils (Yamasaki 2001) and the upper continental crustal composition (Togashi et al 2000) were made (Table 1 and Figure 2). Compared with the average Japanese soils, those on limestone bedrock tend to be rich in Al 2 O 3 and Fe 2 O 3 , and depleted in MgO, CaO, and Na 2 O.…”

Bromine and iodine in Japanese soils determined with polarizing energy dispersive X-ray fluorescence spectrometry

“…Correlation coefficients were calculated using log-transformed values with the exception of those for aluminum (Al), silicon (Si) and iron (Fe), because the frequency distributions of all the other elements were close to log-normal distributions. As for the metallic trace elements in soils, Yamasaki et al (2001) showed that highly positive correlation coefficients (r > 0.8) were observed for a considerable number of combinations. In contrast, more than 80% of the absolute values of correlation coefficients for Br and I against 60 other elements were less than 0.4, indicating that the behavior of these elements in the terrestrial environments could be entirely different from that of most of the other metallic elements.…”

“…A somewhat similar trend was observed for agricultural soils, though the difference between upland soils and paddy fields was much narrower. Table 6 shows the correlation coefficients of Br and I against 60 other elements obtained from analytical data for mainland soils (Yamasaki et al 2001;Takeda et al 2004). As for the results of other groups of samples, the numbers of analyzed elements were not as large as those of mainland soils, and therefore were not included in this attempt.…”

“…In addition, there were two samples from horizon E, 11 samples from horizon G, nine samples from horizon H, and one sample from horizon O. A brief summary of the sampling sites, land use and soil classification has been reported previously (Yamasaki et al 2001;Takeda et al 2004). More detailed information on each sampling site, including its latitude and longitude, profile description and landscape, and general chemical and physical properties of the soils, has been presented elsewhere (Nakai et al 2006).…”

Determination of total contents of bromine, iodine and several trace elements in soil by polarizing energy-dispersive X-ray fluorescence spectrometry

“…Although the concentrations of Zr in the soils were relatively high, the correlation was not so good. That could be attributed to the incomplete decomposition of zircon (ZrSiO 4 ) under the soil decomposition process for the ICP-MS measurement (Yamasaki et al 2001;Tsukada et al 2005;Matsunami et al 2010). Although high correlation coefficients were observed for Cd and Pb, one of the soil samples had remarkably high concentrations and possibly made the coefficients higher than those in lower concentration ranges (Fig.…”