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Jorg Rinklebe - One of the best experts on this subject based on the ideXlab platform.

  • compositional variety of Soil organic matter in mollic floodplain Soil Profiles also an indicator of pedogenesis
    Geoderma, 2018
    Co-Authors: Thilo Rennert, Anna Georgiadis, Nchia Peter Ghong, Jorg Rinklebe
    Abstract:

    Abstract Soils on riverine floodplains in Central Europe are commonly enriched in Soil organic matter (SOM). We analyzed the quantity and qualitative aspects of SOM in three Soil Profiles with mollic horizons along the Elbe River (Germany) after physical fractionation by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy to gain deeper insights into the composition of SOM and the formation of these Soils. In all horizons, the majority of SOM was recovered in the fraction of particulate OM and in that of sand and aggregates, while SOM in the silt and clay fraction always made up

  • geochemical distribution of co cu ni and zn in Soil Profiles of fluvisols luvisols gleysols and calcisols originating from germany and egypt
    Geoderma, 2017
    Co-Authors: Jorg Rinklebe, Sabry M Shaheen
    Abstract:

    Abstract The geochemical fractionation and potential mobilization of Co, Cu, Ni, and Zn were studied in thirteen Soil Profiles originating from Germany and Egypt to assess the potential mobilization of these potentially toxic metals. The German Soils were classified as Eutric Fluvisols, Tidalic Fluvisols, Haplic Gleysols, and Calcic Luvisols, and the Egyptian Soils as Eutric Fluvisols, Sodic Fluvisols, and Haplic Calcisols. The geochemical fractions (acid soluble (F1), reducible (F2), oxidizable (F3), and residual (F4) fraction) of the metals were sequentially extracted using the sequential extraction technique of the Commission of the European Communities Bureau of Reference (BCR). The maximal total concentrations (mg kg − 1 ) of Cu (3242), Ni (105), and Zn (1672) were in the German Eutric Fluvisols, while the maximal concentrations of Co (37) were in the Egyptian Eutric Fluvisols, and those values exceeded the international maximum allowable Soil concentrations. The values of enrichment and contamination factors exhibit a clear indication of dramatic contamination by Cu and Zn at the Eutric Fluvisols along the Wupper River, Germany. The acid soluble fraction of all metals (except for Ni in the Calcic Luvisols) was higher in the German Soils than the Egyptian Soils. The reducible fraction of Co, Cu, Ni, and Zn was the dominant non-residual fraction (as precentages of total) in all Egyptian Soils and in the German Eutric Fluvisols as well as for Zn in the Tidalic Fluvisol and Co in the Calcic Luvisols. The potential mobile fraction (PMF = ∑ F1 − F3) of Co, Cu, Ni, and Zn accounted (% of total) for 39–61, 15–60, 21–57, and 6–44, respectively in the Egyptian Soils, while it accounted for 14–70, 11–92, 2–73, and 8–89, respectively in the German Soils. The high PMF of the metals in the German Eutric Fluvisols, Haplic Gleysols, and Sodic Fluvisols might reflect that the sources of these metals are of anthropogenic origin here. However, the dominance of the metals residual fraction in the Egyptian Soils supports the assumption of the geogenic origin of these metals in these Soils. The canonical discriminant analysis as a multivariate statistical procedure was applied and differentiated the Soils according to their geochemical behavior into four clusters i.e., 1) Eutric Fluvisols, Calcic Luvisols, and Haplic Calcisols; 2) Egyptian Fluvisols (Eutric and Sodic); 3) Haplic Calcisols; and 4) Tidalic Fluvisols. In conclusion, the potential risk of the metals in the anthropogenic polluted Soils is higher than in the Soils naturally enriched with these metals. Therefore, remediation approaches may be needed in the German Eutric Fluvisols, Haplic Gleysols, and Sodic Fluvisols.

  • geochemical fractions of chromium copper and zinc and their vertical distribution in floodplain Soil Profiles along the central elbe river germany
    Geoderma, 2014
    Co-Authors: Sabry M Shaheen, Jorg Rinklebe
    Abstract:

    Abstract The determination of geochemical fractions of heavy metals (HM) in Soils is a key issue when studying their mobility. Therefore, we have determined the geochemical fractions and the vertical distribution of chromium (Cr), copper (Cu), and zinc (Zn) in seven floodplain Soil Profiles in relation to flooding conditions and relevant Soil properties. These Soil Profiles represent two different Soil groups (Mollic Fluvisols and Eutric Gleysols) which differ significantly in flooding duration and Soil properties. The metals were fractionated sequentially to seven fractions as follows: F1: soluble + exchangeable, F2: easily mobilizable, F3: bound to Mn oxides, F4: bound to Soil organic matter (SOM) (might include sulphides), F5: bound to low crystalline (amorphous) Fe oxides, F6: bound by crystalline Fe oxides, and F7: residual fraction. The total Cr, Cu, and Zn concentrations ranged from 54.4 to 134.1, 165.2 to 215.7, and 128.5 to 1097.8 mg kg − 1 , respectively, and exceeded the precautionary values of the BBodSchV (1999). Total metal concentrations correlated significantly to Soil organic carbon (SOC), total sulphur (S t ), and cation exchange capacity (CEC), as well as crystalline and amorphous Fe- and Mn-oxides. The residual fraction was dominant for Cr, the organic bound for Cu, and crystalline Fe oxides for Zn. The potential mobile fraction (PMF = ∑ F1–F6) ranged from 38.4 to 71.4, 63.9 to 85.1, and 51.5 to 83.3% of the total Cr, Cu, and Zn, respectively. However, the mobile fraction (MF = ∑ F1–F2) ranged from 0.96 to 1.84, 2.1 to 4.1, and 9.1 to 28.7% of the total concentrations of Cr, Cu, and Zn, respectively. The order of the PMF in the studied Soil Profiles was Cu > Zn > Cr, while the order of the MF was Zn > Cu > Cr. The PMF of the three metals was positively correlated with SOC and Mn oxides. The PMF was positively correlated with CEC (Cr, Zn), S t (Cr), and Fe oxides (Zn). The PMF of Cu and Zn correlated negatively with clay. The MF of the three metals was correlated negatively with Soil pH. The MF of Zn was correlated positively with clay, SOC, and S t . The MF of Cr was correlated positively with clay, while it correlated negatively with SOC, S t , CEC, and Fe–Mn oxides. The Fluvisols revealed higher total concentrations and potential motilities of Cr, Cu, and Zn compared to the Gleysols. However, the Gleysols had a higher metal mobility compared to Fluvisols due to their longer flooding duration. The solubility of Cr below the average water level in the studied Profiles was higher than above the water level, while the solubility of Cu and Zn above the water level was higher than below the water level in both Soil groups. The potential mobility of the studied metals (especially of Cu followed by Zn), and thus the transfer of these metals into the grassland and food chain, should be high, which might be harmful to the floodplain ecosystem.

  • assessing the mobilization of cadmium lead and nickel using a seven step sequential extraction technique in contaminated floodplain Soil Profiles along the central elbe river germany
    Water Air and Soil Pollution, 2014
    Co-Authors: Jorg Rinklebe, Sabry M Shaheen
    Abstract:

    The mobilization of toxic metals in Soils strongly depends on their bounding in different geochemical fractions. However, the relations between Soil properties and the vertical horizon-specific distribution of different geochemical fractions of cadmium (Cd), lead (Pb), and nickel (Ni) in various floodplain Soil types are limited and have not been studied up to date. Therefore, seven Soil Profiles in three areas along the Elbe River, Germany, which represent the two Soil groups Mollic Fluvisols and Eutric Gleysols, were selected to determine geochemical fractions of Cd, Pb, and Ni. A sequential extraction procedure which fractionate metals into the seven fractions: F1: soluble+exchangeable, F2: easily mobilizable, F3: bound to Mn oxides, F4: bound to Soil organic matter, F5: occluded into amorphous Fe oxides, F6: occluded into crystalline Fe oxides, and F7: residual fraction was used. Concentrations of pseudo-total Cd, Ni, and Pb were exceeded the international trigger action values and governed mainly by Soil organic carbon (SOC), cation exchange capacity, and Fe–Mn sesquioxides. The mobile fraction (∑F1–F2) was dominant for Cd, whereas Pb was mainly bounded in F4/F5, and Ni in F7/F6. Cadmium and Pb reveal a higher potential mobility (∑F1–F6) than Ni. The potential mobile fraction ranged from 90 % to 97 %, 44 % to 61 %, and 83 % to 92 % of the (pseudo)total Cd, Ni, and Pb, respectively. The Gleysols showed a higher mobile fraction and potential mobile fraction than Fluvisols. The mobile fraction of the metals correlated positively with clay, SOC, and total sulfur (St), and negatively with pH and Fe–Mn oxides. Our results indicate that the studied Soils exhibit elevated concentrations of Cd, Ni, and Pb, as well as a high potential mobilization of these metals. Our findings suggest that a release of these toxic metals in floodplain Soils should be considered due to an increased mobilization and the potential environmental risks such as uptake by plants, and thus, the transfer of these metals into the grassland and food chain, as well as transport via waters during periods of flooding.

Sabry M Shaheen - One of the best experts on this subject based on the ideXlab platform.

  • geochemical distribution of co cu ni and zn in Soil Profiles of fluvisols luvisols gleysols and calcisols originating from germany and egypt
    Geoderma, 2017
    Co-Authors: Jorg Rinklebe, Sabry M Shaheen
    Abstract:

    Abstract The geochemical fractionation and potential mobilization of Co, Cu, Ni, and Zn were studied in thirteen Soil Profiles originating from Germany and Egypt to assess the potential mobilization of these potentially toxic metals. The German Soils were classified as Eutric Fluvisols, Tidalic Fluvisols, Haplic Gleysols, and Calcic Luvisols, and the Egyptian Soils as Eutric Fluvisols, Sodic Fluvisols, and Haplic Calcisols. The geochemical fractions (acid soluble (F1), reducible (F2), oxidizable (F3), and residual (F4) fraction) of the metals were sequentially extracted using the sequential extraction technique of the Commission of the European Communities Bureau of Reference (BCR). The maximal total concentrations (mg kg − 1 ) of Cu (3242), Ni (105), and Zn (1672) were in the German Eutric Fluvisols, while the maximal concentrations of Co (37) were in the Egyptian Eutric Fluvisols, and those values exceeded the international maximum allowable Soil concentrations. The values of enrichment and contamination factors exhibit a clear indication of dramatic contamination by Cu and Zn at the Eutric Fluvisols along the Wupper River, Germany. The acid soluble fraction of all metals (except for Ni in the Calcic Luvisols) was higher in the German Soils than the Egyptian Soils. The reducible fraction of Co, Cu, Ni, and Zn was the dominant non-residual fraction (as precentages of total) in all Egyptian Soils and in the German Eutric Fluvisols as well as for Zn in the Tidalic Fluvisol and Co in the Calcic Luvisols. The potential mobile fraction (PMF = ∑ F1 − F3) of Co, Cu, Ni, and Zn accounted (% of total) for 39–61, 15–60, 21–57, and 6–44, respectively in the Egyptian Soils, while it accounted for 14–70, 11–92, 2–73, and 8–89, respectively in the German Soils. The high PMF of the metals in the German Eutric Fluvisols, Haplic Gleysols, and Sodic Fluvisols might reflect that the sources of these metals are of anthropogenic origin here. However, the dominance of the metals residual fraction in the Egyptian Soils supports the assumption of the geogenic origin of these metals in these Soils. The canonical discriminant analysis as a multivariate statistical procedure was applied and differentiated the Soils according to their geochemical behavior into four clusters i.e., 1) Eutric Fluvisols, Calcic Luvisols, and Haplic Calcisols; 2) Egyptian Fluvisols (Eutric and Sodic); 3) Haplic Calcisols; and 4) Tidalic Fluvisols. In conclusion, the potential risk of the metals in the anthropogenic polluted Soils is higher than in the Soils naturally enriched with these metals. Therefore, remediation approaches may be needed in the German Eutric Fluvisols, Haplic Gleysols, and Sodic Fluvisols.

  • geochemical fractions of chromium copper and zinc and their vertical distribution in floodplain Soil Profiles along the central elbe river germany
    Geoderma, 2014
    Co-Authors: Sabry M Shaheen, Jorg Rinklebe
    Abstract:

    Abstract The determination of geochemical fractions of heavy metals (HM) in Soils is a key issue when studying their mobility. Therefore, we have determined the geochemical fractions and the vertical distribution of chromium (Cr), copper (Cu), and zinc (Zn) in seven floodplain Soil Profiles in relation to flooding conditions and relevant Soil properties. These Soil Profiles represent two different Soil groups (Mollic Fluvisols and Eutric Gleysols) which differ significantly in flooding duration and Soil properties. The metals were fractionated sequentially to seven fractions as follows: F1: soluble + exchangeable, F2: easily mobilizable, F3: bound to Mn oxides, F4: bound to Soil organic matter (SOM) (might include sulphides), F5: bound to low crystalline (amorphous) Fe oxides, F6: bound by crystalline Fe oxides, and F7: residual fraction. The total Cr, Cu, and Zn concentrations ranged from 54.4 to 134.1, 165.2 to 215.7, and 128.5 to 1097.8 mg kg − 1 , respectively, and exceeded the precautionary values of the BBodSchV (1999). Total metal concentrations correlated significantly to Soil organic carbon (SOC), total sulphur (S t ), and cation exchange capacity (CEC), as well as crystalline and amorphous Fe- and Mn-oxides. The residual fraction was dominant for Cr, the organic bound for Cu, and crystalline Fe oxides for Zn. The potential mobile fraction (PMF = ∑ F1–F6) ranged from 38.4 to 71.4, 63.9 to 85.1, and 51.5 to 83.3% of the total Cr, Cu, and Zn, respectively. However, the mobile fraction (MF = ∑ F1–F2) ranged from 0.96 to 1.84, 2.1 to 4.1, and 9.1 to 28.7% of the total concentrations of Cr, Cu, and Zn, respectively. The order of the PMF in the studied Soil Profiles was Cu > Zn > Cr, while the order of the MF was Zn > Cu > Cr. The PMF of the three metals was positively correlated with SOC and Mn oxides. The PMF was positively correlated with CEC (Cr, Zn), S t (Cr), and Fe oxides (Zn). The PMF of Cu and Zn correlated negatively with clay. The MF of the three metals was correlated negatively with Soil pH. The MF of Zn was correlated positively with clay, SOC, and S t . The MF of Cr was correlated positively with clay, while it correlated negatively with SOC, S t , CEC, and Fe–Mn oxides. The Fluvisols revealed higher total concentrations and potential motilities of Cr, Cu, and Zn compared to the Gleysols. However, the Gleysols had a higher metal mobility compared to Fluvisols due to their longer flooding duration. The solubility of Cr below the average water level in the studied Profiles was higher than above the water level, while the solubility of Cu and Zn above the water level was higher than below the water level in both Soil groups. The potential mobility of the studied metals (especially of Cu followed by Zn), and thus the transfer of these metals into the grassland and food chain, should be high, which might be harmful to the floodplain ecosystem.

  • assessing the mobilization of cadmium lead and nickel using a seven step sequential extraction technique in contaminated floodplain Soil Profiles along the central elbe river germany
    Water Air and Soil Pollution, 2014
    Co-Authors: Jorg Rinklebe, Sabry M Shaheen
    Abstract:

    The mobilization of toxic metals in Soils strongly depends on their bounding in different geochemical fractions. However, the relations between Soil properties and the vertical horizon-specific distribution of different geochemical fractions of cadmium (Cd), lead (Pb), and nickel (Ni) in various floodplain Soil types are limited and have not been studied up to date. Therefore, seven Soil Profiles in three areas along the Elbe River, Germany, which represent the two Soil groups Mollic Fluvisols and Eutric Gleysols, were selected to determine geochemical fractions of Cd, Pb, and Ni. A sequential extraction procedure which fractionate metals into the seven fractions: F1: soluble+exchangeable, F2: easily mobilizable, F3: bound to Mn oxides, F4: bound to Soil organic matter, F5: occluded into amorphous Fe oxides, F6: occluded into crystalline Fe oxides, and F7: residual fraction was used. Concentrations of pseudo-total Cd, Ni, and Pb were exceeded the international trigger action values and governed mainly by Soil organic carbon (SOC), cation exchange capacity, and Fe–Mn sesquioxides. The mobile fraction (∑F1–F2) was dominant for Cd, whereas Pb was mainly bounded in F4/F5, and Ni in F7/F6. Cadmium and Pb reveal a higher potential mobility (∑F1–F6) than Ni. The potential mobile fraction ranged from 90 % to 97 %, 44 % to 61 %, and 83 % to 92 % of the (pseudo)total Cd, Ni, and Pb, respectively. The Gleysols showed a higher mobile fraction and potential mobile fraction than Fluvisols. The mobile fraction of the metals correlated positively with clay, SOC, and total sulfur (St), and negatively with pH and Fe–Mn oxides. Our results indicate that the studied Soils exhibit elevated concentrations of Cd, Ni, and Pb, as well as a high potential mobilization of these metals. Our findings suggest that a release of these toxic metals in floodplain Soils should be considered due to an increased mobilization and the potential environmental risks such as uptake by plants, and thus, the transfer of these metals into the grassland and food chain, as well as transport via waters during periods of flooding.

Haibo Zhang - One of the best experts on this subject based on the ideXlab platform.

  • occurrence of red clay horizon in Soil Profiles of the yellow river delta implications for accumulation of heavy metals
    Journal of Geochemical Exploration, 2017
    Co-Authors: Haibo Zhang, Fang Song, Yongming Luo
    Abstract:

    Abstract The source-area weathering and pedogenesis processes in the alluvial Soil Profiles might affect depth distribution of heavy metals. Red clay horizon (RCH) with a thickness of 5–50 cm in a 1 m Soil profile has been found ubiquitously in the Yellow River Delta (YRD). The occurrence of this RCH was supposed to be related with the frequent shifting of the Yellow River tail channel in the Yellow River Delta (YRD). The geochemical features of the RCH were distinct from its upper or lower yellow silt horizon (YSH). The average median grain size of the RCH (10.5 μm) was almost three times lower than that of the YSH (29.9 μm). Meanwhile, the RCH was characterized of higher chemical index of alteration (CIA), magnetic susceptibility ( χ lf ) and frequency-dependent magnetic susceptibility ( χ fd ) values than the YSH, which implied a stronger source-area weathering and pedogenesis intensity of the RCH. Besides the distinctive characteristics of the RCH, it also accumulated significantly ( p χ lf and χ fd , however, such a correlation was not found except for Pb in the YSH. In addition, result of BCR sequential extraction indicated that a higher percentage of Fe–Mn oxides associated fraction was in the RCH than in the YSH for the heavy metals of Pb and Co. Cadmium was observed at higher percentage of exchangeable fraction in the RCH than in the YSH, implying a higher environmental risk of the Cd in the RCH.

  • burden and depth distribution of organochlorine pesticides in the Soil Profiles of yangtze river delta region china implication for sources and vertical transportation
    Geoderma, 2009
    Co-Authors: Haibo Zhang, Qingbo Li
    Abstract:

    Abstract Soil is an important source of organochlorine pesticides (OCPs) to other environmental media and organisms. Large amounts of OCPs, such as hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), have been intensively applied in the croplands of Yangtze River Delta (YRD) Region before being officially banned from use for agriculture in 1980s, China. Forty-four Soil Profiles which represent seven major Soil types in YRD region were chosen and a total of 169 horizon samples were collected for analysis of HCH and DDT. The highest residual level of DDT (484.24 μg/kg d.w.) and HCH (17.93 μg/kg d.w.) was detected in cotton field and paddy field, respectively. It is estimated that approximately 580 tons of DDT is reserved in the Soil depth of 100 cm at present, which is around two times higher than that of HCH. Unexpectedly, about 60% and 80% of the residual DDT and HCH on average are buried underlying layers within a depth of 15–100 cm respectively, imposing potential risks to shallow groundwater and underground ecosystem. Depth distribution of DDT and HCH compositions is presented fairly constant in the layers above the plough pan of paddy Soil, implying that their downward migration is induced by bioturbation principally. While in the layers beneath the plough pan, dominance of more water-soluble compounds infer leaching of DDT and HCH by irrigation and rainfall. In dry land and upland, downward transportation mechanisms of DDT and HCH are shown as site-specific according to their depth distribution.

  • distribution of polycyclic aromatic hydrocarbons in thirty typical Soil Profiles in the yangtze river delta region east china
    Environmental Pollution, 2007
    Co-Authors: Lifeng Ping, Haibo Zhang, Quanlian Li, Luhua Wu
    Abstract:

    Abstract Polycyclic aromatic hydrocarbons (PAHs) were quantified in 30 Soil Profiles from the Yangtze River Delta Region, in east China. Relative concentrations of PAH compounds with different benzene rings and ratios of fluoranthene to fluoranthene plus pyrene and benz(a)anthracene to benz(a)anthracene plus chrysene were used to identify the possible sources of Soil PAHs. Total concentrations of 15 PAHs in topSoils ranged from 8.6 to 3881 μg kg −1 with an average of 397 μg kg −1 . Half of the Soil samples were considered to be contaminated with PAHs (>200 μg kg −1 ) and two sampling sites were heavily polluted by PAHs with concentrations >1000 μg kg −1 . Phenanthrene was found in Soils below a depth of 100 cm in half of the sampling sites, but the detectable ratio of benzo(a)pyrene decreased sharply from 100% in topSoil to 0 in the 4th horizon.

Bal Ram Singh - One of the best experts on this subject based on the ideXlab platform.

  • fractionation and mobility of copper lead and zinc in Soil Profiles in the vicinity of a copper smelter
    Journal of Environmental Quality, 2001
    Co-Authors: Cezary Kabala, Bal Ram Singh
    Abstract:

    dias, 1992; Singh, 1997; Ahumada et al., 1999). Watersoluble and exchangeable forms are considered readily Four Soil Profiles located near a copper smelter in Poland were mobile and available to plants, while metals incorpoinvestigated for the distribution and chemical fractions of Cu, Pb, and Zn and their mobility in relation to Soil properties. Contamination rated into crystalline lattices of clays appear relatively with heavy metals was primarily restricted to surface horizons and inactive. The other forms—precipitated as carbonate, the extent of contamination was 7- to 115-fold for Cu, 30-fold for Pb, occluded in Fe, Mn, and Al oxides, or complexed with and 6-fold for Zn as compared with subsurface horizons. In the less- organic matter—could be considered relatively active or contaminated fine-textured Soil, the metals were distributed in the order: firmly bound, depending upon the actual combination of residual .. Fe‐Mn oxides occluded . organically complexed . ex- physical and chemical properties of Soil (Sposito et al., changeable and specifically adsorbed, while the order for sandy Soils 1982; Shuman, 1985). Thus, Soil texture (clay content), was: residual . organically complexed . Fe‐Mn oxides occluded . pH, organic matter, and Fe‐Mn oxides have been found exchangeable and specifically adsorbed. The contaminated surface to be the most important Soil properties and components horizons of these Profiles showed no consistent pattern of metal distriinfluencing the lability and biological uptake of heavy bution. However, the common features of highly contaminated Soils

  • fractionation and mobility of copper lead and zinc in Soil Profiles in the vicinity of a copper smelter
    Journal of Environmental Quality, 2001
    Co-Authors: Cezary Kabala, Bal Ram Singh
    Abstract:

    Four Soil Profiles located near a copper smelter in Poland were investigated for the distribution and chemical fractions of Cu, Pb, and Zn and their mobility in relation to Soil properties. Contamination with heavy metals was primarily restricted to surface horizons and the extent of contamination was 7- to 115-fold for Cu, 30-fold for Pb, and 6-fold for Zn as compared with subsurface horizons. In the less-contaminated fine-textured Soil, the metals were distributed in the order: residual >> Fe-Mn oxides occluded > organically complexed > exchangeable and specifically adsorbed, while the order for sandy Soils was: residual > organically complexed > Fe-Mn oxides occluded > exchangeable and specifically adsorbed. The contaminated surface horizons of these Profiles showed no consistent pattern of metal distribution. However, the common features of highly contaminated Soils were very low percentage of residual fraction and the dominance of the NH4OAc extractable fraction. The sum of mobile metal fractions was generally < 10% in subsurface horizons, while in the contaminated surface horizons these fractions made up 50% of the total metal contents. Soil properties contributed more to the relative distribution of the metal fractions in the studied Profiles than did the distance and direction to the source of pollution. The amounts of metal extracted by 0.01 M CaCl2 accounted for only a small part of the same metals extracted by NH4OAc. The mobility indexes of metals correlated positively and significantly with the total content of metals and negatively with the clay content.

Yuichi Onda - One of the best experts on this subject based on the ideXlab platform.

  • vertical distribution and temporal changes of 137cs in Soil Profiles under various land uses after the fukushima dai ichi nuclear power plant accident
    Journal of Environmental Radioactivity, 2015
    Co-Authors: Junko Takahashi, Kenji Tamura, Tomoya Suda, Ryo Matsumura, Yuichi Onda
    Abstract:

    Abstract We monitored the vertical distribution of 137Cs in Soil Profiles under eight different land uses for the 2 y after the Fukushima Dai-ichi Nuclear Power Plant accident, and discussed the temporal changes in the early-stage of the migration and the determinants of the initial distribution. The Soil samples were collected for four surveys using a scraper plate at each study site, which consisted of three forests (mixed forest, mature cedar, and young cedar), two grasslands (pasture and meadow) and three abandoned agricultural fields (farm land, tobacco field, and paddy field). The land use patterns have a large influence on some Soil properties and the migration processes of 137Cs above ground, resulting in different distribution of 137Cs in those Soil Profiles. Specifically, the secondary deposition of 137Cs from the coniferous canopy, retention of 137Cs by litter layer, and the homogenization of 137Cs concentrations in surface Soil by natural Soil mixing such as the disturbance by cattle grazing, roots growing and the formation of needle ice were important to cause redistribution of the deposited 137Cs. Only in the paddy field, the 137Cs inventory in subsurface Soils (5–10 cm) gradually increased and comprised 26% of the total 137Cs in 2 y, showing the downward migration of 137Cs to subsurface Soil. In the other sites, it was considered that 137Cs were strongly adsorbed by Soil particles and rarely migrated downward as soluble form. Vertical distributions during the first survey were able to be used as the initial distributions and were well fitted to the exponential equation. The distribution parameters α (relaxation depth) and β (relaxation mass depth), calculated by the exponential equation were correlated with RIP (r = −0.806, p

  • vertical distribution and temporal changes of 137cs in Soil Profiles under various land uses after the fukushima dai ichi nuclear power plant accident
    Journal of Environmental Radioactivity, 2015
    Co-Authors: Junko Takahashi, Kenji Tamura, Tomoya Suda, Ryo Matsumura, Yuichi Onda
    Abstract:

    We monitored the vertical distribution of 137Cs in Soil Profiles under eight different land uses for the 2 y after the Fukushima Dai-ichi Nuclear Power Plant accident, and discussed the temporal changes in the early-stage of the migration and the determinants of the initial distribution. The Soil samples were collected for four surveys using a scraper plate at each study site, which consisted of three forests (mixed forest, mature cedar, and young cedar), two grasslands (pasture and meadow) and three abandoned agricultural fields (farm land, tobacco field, and paddy field). The land use patterns have a large influence on some Soil properties and the migration processes of 137Cs above ground, resulting in different distribution of 137Cs in those Soil Profiles. Specifically, the secondary deposition of 137Cs from the coniferous canopy, retention of 137Cs by litter layer, and the homogenization of 137Cs concentrations in surface Soil by natural Soil mixing such as the disturbance by cattle grazing, roots growing and the formation of needle ice were important to cause redistribution of the deposited 137Cs. Only in the paddy field, the 137Cs inventory in subsurface Soils (5–10 cm) gradually increased and comprised 26% of the total 137Cs in 2 y, showing the downward migration of 137Cs to subsurface Soil. In the other sites, it was considered that 137Cs were strongly adsorbed by Soil particles and rarely migrated downward as soluble form. Vertical distributions during the first survey were able to be used as the initial distributions and were well fitted to the exponential equation. The distribution parameters α (relaxation depth) and β (relaxation mass depth), calculated by the exponential equation were correlated with RIP (r = −0.806, p < 0.05), macro pore (r = 0.651, p = 0.11), and dispersible fine particle content (r = 0.856, p < 0.05). It indicated that the initial distribution would be influenced by the Cs fixation ability of Soil, and the penetration process of water and particles in Soils.