A man-made tracer for soil erosion exists in the world-wide fallout of <sup>137</sup>Cs from nuclear test. Most of the fallout occurred from 1956 through 1965 with maximum deposition rates in 1963—1964. R...A man-made tracer for soil erosion exists in the world-wide fallout of <sup>137</sup>Cs from nuclear test. Most of the fallout occurred from 1956 through 1965 with maximum deposition rates in 1963—1964. Reiatively little <sup>137</sup>Cs has been deposited since 1970. Cesium-137 is strongly adsorbed within the upper horizons of soil and resists leaching through soil. Since <sup>137</sup>Cs has a half-life of 30 a, it is a good tracer for long-term soil particle movement.展开更多
基金Project supported by the National Natural Science Foundation of China and Xi'an Laboratory Foundation.
文摘A man-made tracer for soil erosion exists in the world-wide fallout of <sup>137</sup>Cs from nuclear test. Most of the fallout occurred from 1956 through 1965 with maximum deposition rates in 1963—1964. Reiatively little <sup>137</sup>Cs has been deposited since 1970. Cesium-137 is strongly adsorbed within the upper horizons of soil and resists leaching through soil. Since <sup>137</sup>Cs has a half-life of 30 a, it is a good tracer for long-term soil particle movement.