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Based upon the analysis of Cs and grain-size parameters, the total amounts of 137Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 137Cs in the lacustrine sediments exhibits three 137Cs activity maxima and one minimum. The major maximum corresponds to the global I37Cs fallout in 1963; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1986 and complete desiccation of the lake in 1994, respectively. The minimum corresponds to aeolian deposition caused by extensive reclamation in the late 1980s and early 1990s. The 137Cs data set was used to evaluate average sedimentation rate of the Dalian Lake since 1963. The deposition was stable in 1963-1986 and 1994-1998, and it was rapid during 1986?994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduce by human interference in arid/semiarid regions as in humid regions.
Based upon the analysis of Cs and grain-size parameters, the total amounts of 137Cs deposition by wind and water in the Dalian Lake of Gonghe Basin, Qinghai Province are defined. The vertical profile of 137Cs in the lacustrine sediments exhibits three 137Cs activity maxima and one minimum. The major maximum corresponds to the global I37Cs fallout in 1963; the two secondary maxima correspond to the leakage of the Chernobyl reactor in 1986 and complete desiccation of the lake in 1994, respectively. The minimum correspondence to aeolian deposition caused by extensive reclamation In the late 1980s and early 1990s. The 137Cs data set was used to evaluate the average sedimentation rate of the Dalian Lake since 1963. The deposition was stable in 1963-1986 and 1994-1998, and was was during 1986? 994. This preliminary study reveals that l37Cs has the same potential to trace environmental changes introduced by human interference in arid / semiarid regions as in humid regions.