title: Fallout volume and litter type affect137Cs concentration difference in litter between forest and stream environments.
abstract: It is important to understand the changes in the137Cs concentration in litter through leaching when considering that137Cs is transferred from basal food resources to animals in forested streams. We found that the difference of137Cs activity concentration in litter between forest and stream was associated with both litter type and137Cs fallout volume around Fukushima, Japan. The137Cs activity concentrations in the litter of evergreen conifers tended to be greater than those in the litter of broad-leaved deciduous trees because of the absence of deciduous leaves during the fallout period in March 2011. Moreover,137Cs activity concentrations in forest litter were greater with respect to the137Cs fallout volume. The137Cs activity concentrations in stream litter were much lower than those in forest litter when those in forest litter were higher. The137Cs leaching patterns indicated that the differences in137Cs activity concentration between forest and stream litter could change with changes in both fallout volume and litter type. Because litter is an important basal food resource in the food webs of both forests and streams, the137Cs concentration gradient reflects to possible137Cs transfer from lower to higher trophic animals. Our findings will improve our understanding of the spatial heterogeneity and variability of137Cs concentrations in animals resident to the contaminated landscape.
authors.affiliation: Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo, 112-8551, Japan. Electronic address: boundary.0008@gmail.com.
authors.forename: Masaru
authors.initials: M
authors.lastname: Sakai
authors.affiliation: Institute of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, 183-8509, Japan. Electronic address: gomit@cc.tuat.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Gomi
authors.affiliation: Faculty of Environmental Earth Science, Hokkaido University, N10, W5, Kita-ku, Sapporo, Hokkaido, 060-0860, Japan. Electronic address: negishi@ees.hokudai.ac.jp.
authors.forename: Junjiro N
authors.initials: JN
authors.lastname: Negishi
mesh_terms: D002588:Cesium Radioisotopes / Q000032:analysis*; D017753:Ecosystem; D065928:Forests; D062406:Fukushima Nuclear Accident; D007564:Japan; D018515:Plant Leaves / Q000737:chemistry*; D011834:Radiation Monitoring; D045483:Rivers; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
chemical_list: D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive
keywords: Basal food resource; Forest ecosystem; Leaching; Radiocesium; Stream ecosystem