Comparison of 0.1 M Stable CsCl and 1 M NHNO as an Extraction Reagent to Evaluate Cs-137 Mobility in Soils.

To evaluate the mobility and bioavailability of Cs in soils, we compared the extraction of Cs with stable Cs and ammonium solutions from Cs-contaminated minerals and soils. The extraction yields of Cs with stable Cs were significantly lower than those with ammonium for minerals with frayed edge sites, but such differences were not observed for minerals without frayed edge sites. The amount of Cs extracted with stable Cs from soils was lower than, or equal to, that extracted with ammonium.

Coniferous coverage as well as catchment steepness influences local stream nitrate concentrations within a nitrogen-saturated forest in central Japan.

High concentrations of nitrate have been detected in streams flowing from nitrogen-saturated forests; however, the spatial variations of nitrate leaching within those forests and its causes remain poorly explored. The aim of this study is to evaluate the influences of catchment topography and coniferous coverage on stream nitrate concentrations in a nitrogen-saturated forest. We measured nitrate concentrations in the baseflow of headwater streams at 40 montane forest catchments on Mount Tsukuba in central Japan, at three-month intervals for 1 year, and investigated their relationship with catchment topography and with coniferous coverage.

Varying sensitivity of mountainous streamwater base-flow [Formula: see text]concentrations to N deposition in the northern suburbs of Tokyo.

Ecosystems of suburban landscapes (i.e., forest, inland water ecosystem) are threatened by high nitrogen (N) loadings derived from urban air pollutants.

Migration of Ag, In, Sn, Sb, and Bi and Their Chemical Forms in a Monolith Lysimeter Filled with a Contaminated Andosol.

Despite the wide use of trace metals in various technologies, such as chemical industries and electronic equipment, insufficient information is available on their behavior in the environment. We investigated changes in chemical forms and vertical distribution during the migration processes of trace metals, whose usage is currently increasing rapidly, such as Ag, In, Sn, Sb, and Bi, in soil contaminated with the equivalent of 50-100 times the background concentrations of these metals using an indoor control type monolith lysimeter filled with Andosol during an 8-year monitoring period. The vertical distribution of the total elemental concentrations, the mobile fractions (exchangeable, carbonate-bound, and metal-organic complex-bound) in soils, and the total elemental concentrations in soil solutions were analyzed to study trace metal migration in soil.

Microbial nitrification in throughfall of a Japanese cedar associated with archaea from the tree canopy.

To investigate the nitrification potential of phyllospheric microbes, we incubated throughfall samples collected under the canopies of Japanese cedar (Cryptomeria japonica) and analyzed the transformation of inorganic nitrogen in the samples. Nitrate concentration increased in the unfiltered throughfall after 4 weeks of incubation, but remained nearly constant in the filtered samples (pore size: 0.2 and 0.

Uptake and translocation of radiocesium in cedar leaves following the Fukushima nuclear accident.

Cryptomeria japonica trees in the area surrounding Fukushima, Japan, intercepted (137)Cs present in atmospheric deposits soon after the Fukushima nuclear accident in March 2011. To study the uptake and translocation of (137)Cs in C. japonica leaves, we analyzed activity concentrations of (137)Cs and the concentration ratios of (137)Cs to (133)Cs ((137)Cs/(133)Cs) in old and new leaves of C.

Pollution of montane soil with Cu, Zn, As, Sb, Pb, and nitrate in Kanto, Japan.

Soil cores and rainwater were sampled under canopies of Cryptomeria japonica in four montane areas along an atmospheric depositional gradient in Kanto, Japan. Soil cores (30cm in depth) were divided into 2-cm or 4-cm segments for analysis. Vertical distributions of elemental enrichment ratios in soils were calculated as follows: (X/Al)(i)/(X/Al)(BG) (where the numerator and denominator are concentration ratios of element-X and Al in the i- and bottom segments of soil cores, respectively).

Weathering and dissolution rates among Pb shot pellets of differing elemental compositions exposed to various aqueous and soil conditions.

The present study was performed to investigate the weathering and dissolution rates of Pb shot pellets differing in elemental composition (Pb, Sb, and As) exposed under various aqueous and soil conditions using five commercial shot pellet preparations. Upon immersion in distilled water, the dissolution rates of shot pellets, calculated from the difference in weight before versus after immersion, decreased with increasing Sb + As contents and the dominant precipitate was hydrocerussite. These subsidiary ingredients may be related to the difficulty of metallic Pb oxidation (transformation to PbO).

Evolutionary control of leaf element composition in plants.

Leaf nitrogen (N) and phosphorus (P) concentrations are correlated in plants. Higher-level phylogenetic effects can influence leaf N and P. By contrast, little is known about the phylogenetic variation in the leaf accumulation of most other elements in plant tissues, including elements with quantitatively lesser roles in metabolism than N, and elements that are nonessential for plant growth.

Simultaneous determination of atmospheric sulfur and nitrogen oxides using a battery-operated portable filter pack sampler.

We developed a method to analyze atmospheric SO(x) (particulate SO(4)(2-)+ gaseous SO(2)) and NO(x) (NO + NO(2)) simultaneously using a battery-operated portable filter pack sampler. NO(x) determination using a filter pack method is new. SO(x) and NO(x) were collected on a Na(2)CO(3) filter and PTIO (2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) + TEA (triethanolamine) filters (6 piled sheets), respectively.