title: Effective and ecological half-lives of 137Cs in cow's milk in alpine agriculture.
abstract: In the mountainous "Hohe Tauern" region of Salzburg (Austria), milk samples have been collected in a long-term montitoring programme since 1988, at eight alpine sites used for extensive, seasonal stock farming. For this alpine environment with its acidic soils developed on silicate bedrock, high soil-to-plant transfer factors and long-lasting (137)Cs contamination levels in milk--the main product of seasonal agriculture at elevated altitudes--are characteristic features. The decrease in (137)Cs concentration in milk measured since 1988 turned out to be best described by one or two effective half-lives. For the period from 1993 to 2007, which can be modelled with one effective half-life for all sites, effective half-lives between 3.7 and 15.0 years (ecological half-lives: 4.3-29.9 years) were obtained. The effective half-life increases with mean altitude of the investigated graze pastures, probably due to reduced migration velocities of (137)Cs and low (137)Cs half-value depths of a few centimetres in the soil.
authors.affiliation: Division of Physics and Biophysics, University Salzburg, Salzburg, Austria. herbert.lettner@sbg.ac.at
authors.forename: Herbert
authors.initials: H
authors.lastname: Lettner
authors.forename: Alexander
authors.initials: A
authors.lastname: Hubmer
authors.forename: Peter
authors.initials: P
authors.lastname: Bossew
authors.forename: Friederike
authors.initials: F
authors.lastname: Strebl
authors.forename: Friedrich
authors.initials: F
authors.lastname: Steinhäusler
mesh_terms: D000383:Agriculture; D000818:Animals; D001317:Austria; D002588:Cesium Radioisotopes / Q000493:pharmacokinetics; D003625:Data Collection; D017753:Ecosystem; D020387:Food Chain; D006207:Half-Life; D008892:Milk / Q000378:metabolism*; D012987:Soil; D013997:Time Factors
chemical_list: D002588:Cesium Radioisotopes; D012987:Soil
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