Application of Radioactive Fallout Cesium-137 for Measuring Soil Erosion and Sediment Accumulation Rates and Patterns: A Review
Application of Radioactive Fallout Cesium-137 for Measuring Soil Erosion and Sediment Accumulation Rates and Patterns: A Review
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DOI：
10.2134/jeq1990.00472425001900020006x
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发表时间：
1990-04
影响因子：
2.4
通讯作者：
J. Ritchie;J. Mchenry
中科院分区：
文献类型：
--
作者：
J. Ritchie;J. Mchenry
大气核试验在整个景观中沉积的放射性沉降物铯（铯-137）被土壤颗粒强烈吸收，限制了其通过化学和生物过程的移动。大多数铯在环境中的运动是通过物理过程进行的；因此，Cs是研究侵蚀和沉积作用的独特示踪剂。流域的铯 137 损失已被证明与通过通用土壤流失方程 (USLE) 计算或通过小径流板测量的土壤流失密切相关。通过测量整个景观垂直和水平面上铯的空间格局，可以测量流域不同部分的土壤流失或沉积率。即使在景观单元内，也可以绘制土壤的重新分布图，并测量和绘制各个田地不同部分的侵蚀或沉积率。沉积物积累率可以通过比较沉积物中铯的垂直分布与大气中沉降物铯的时间沉积来确定沉积物层位。使用这些标明日期的沉积物层位，可以测量沉积物积累速率。对这些测年层位位置的解释必须考虑沉积物的粒径、沉积物的再加工、铯的扩散运动以及沉积过程中物理过程的时间速率。 Cs 技术可用于确定各种沉积环境中的沉积物积累速率，包括水库、湖泊、湿地、沿海地区和洪泛区。参考书目显示，Cs 已被广泛用于研究世界各地许多不同环境中的侵蚀和沉积。
Radioactive fallout Cs (cesium-137) deposited across the landscape from atmospheric nuclear tests is strongly absorbed on soil particles limiting its movement by chemical and biological processes. Most Cs movement in the environment is by physical processes; therefore, Cs is a unique tracer for studying erosion and sedimentation. Cesium-137 loss from a watershed has been shown to correlate strongly with soil loss calculated by the Universal Soil Loss Equation (USLE) or measured from small runoff plates. By measuring spatial patterns of Cs in vertical and horizontal planes across the landscape, rates of soil loss or deposition can be measured for different parts of a watershed. Even within landscape units, redistribution of soil can be mapped and erosion or deposition rates for different parts of individual fields measured and mapped. Sediment accumulation rates can be measured by comparing the vertical distribution of Cs in sediments with the temporal deposition of fallout Cs from the atmosphere to locate sediment horizons. Using these dated sediment horizons, sediment accumulation rates can be measured. Interpretations about the location of these dated horizons must consider particle size of the sediments, reworking of deposited sediments, diffusional movement of Cs, and time rates of physical process in the sedimentation process. The Cs technique can be used to determine sediment accumulation rates in a wide variety of depositional environments including reservoirs, lakes, wetlands, coastal areas, and floodplains. The bibliography shows that Cs has been used widely for studying erosion and sedimentation in many different environments around the world.