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Fallout cesium-137 (137 Cs) measurements have been used in investigations of water-induced soil erosion in a wide range of environments and in many different areas of the world over the past 20 yr.However, the existing calibration procedures commonly used for deriving quantitative estimates of soil redistribution rates from 137 Cs measurements …
The fallout radionuclide cesium-137 (137 Cs) has been successfully used in soil erosion studies worldwide. However, discrepancies often exist between the erosion rates estimated using …
For a given P and P′, a long-term lower upslope erosion rate yields higher 137 Cs concentrations in the soil, mobilized sediment, and deposits with time. A higher 137 Cs concentration in the deposits means a lower sedimentation rate. This result indicates that the upslope erosion rates are positively correlated to the downslope deposition ...
This paper describes a method of soil erosion and soil movement measurements using 137 Cs as a tracer. This technique has been used successfully employed for more than 30 years. Caesium-137 is a valuable tracer to study soil erosion. Its chemical and biological move- ment in soil is limited. Practically all redeposition of caesium-137 in soil after fallout occurs …
Olson et al. determine the soil erosion rates in cropland of west central Illinois using a magnetic tracer (fly ash) and radio-cesium (cesium-137). The fly ash and cesium-137 accumulation on a stable cropland/hayland summit was determined using a spiral transect. This reference site was used as a baseline and then compared with the fly …
Abstract. Soil degradation by accelerated erosion is a serious problem and will remain so during the 21st century, especially in developing countries of the tropics and subtropics. Yet, its extent, severity, and economic and environmental impacts are debatable. Estimates of global and regional land area affected are tentative and subjective.
Soil samples from each depth was air-dried, weighed, crushed, and passed though a 1 mm sieve.For each slope position, the soil from corresponding depth …
Most 137Cs movement in the environment is by physical processes; therefor, 137Cs is a unique tracer for studying erosion and sedimentation. Cesium-137 loss from a watershed has been shown to ...
Abstract The potential for using the radionuclide caesium-137 as an environmental tracer to indicate sources of soil erosion in the Chinese Loess Plateau is introduced. The caesium-137 contents of soil profiles have been used to estimate soil erosion losses from different topographic and land use conditions at Lishi, Shanxi Province, and Luochuan, Shaanxi …
247 Caesium-137 estimation of soil erosion rates in China was about 1.0 Bq kg"1.Measurement precision was typically of the order ±5% (at 2 s.d.). RESULTS The site details and caesium-137 contents ...
Radioactive caesium- 137 (137 Cs) can be used as a tracer to infer sediment dynamics due not only to its long radioactive half-life but also its affinity for fine sediment.A novel advanced ...
The caesium 137 technique has become an important tool for investigating soil erosion. It permits retrospective assessment of medium-term erosion rates. The application of the technique requires only one field visit, and the results can be provided within a relatively short time.
Atmospheric deposition rates of 90Sr and analysis of soil samples from non-eroded sites indicated base levels of total soil 137Cs were approximately 2700 Bq m−2 in southern Ontario in 1985. Measured 137Cs losses (1965–1976) from long-term runoff plots were significantly correlated to measured soil losses during the same period. Monitoring …
Application of radioactive fallout cesium-137 for measuring soil erosion and sediment accumulation rates and patterns: a review
Most 137 Cs movement in the environment is by physical processes; therefore, 137 Cs is a unique tracer for studying erosion and sedimentation. Cesium-137 loss from …
The soil erosion was studied by 137Cs technique in Yatagan basin in Western Turkey, where there exist intensive agricultural activities. This region is subject to serious soil loss problems and yet there is not any erosion data towards soil management and control guidelines. During the soil survey studies, the soil profiles were examined …
The 137 Cs method has been widely used to estimate soil erosion and redistribution but has seldom been used to evaluate process-based erosion models. This study evaluated spatial erosion patterns predicted by the Water Erosion Prediction Project (WEPP) model using 137 Cs-estimated spatially distributed erosion data and quantified …
Soil erosion and deposition were estimated using Cs-137 activity within a 7.25-ha field/forest system in the southeastern coastal plain. Soil eroded from the field was deposited both in the riparian (streamside) forest ecosystem and in downslope areas of the field. Total activity, depth to peak activity, and depth to zero activity increased downslope …
However, given the short half-life of 137 Cs, this well-established soil erosion tracer may be replaced by 239+240 Pu as a surrogate in the future and, therefore, the 239+240 Pu baseline map may ...
Fallout cesium-137 ( 137 Cs) measurements have been used in investigations of water-induced soil erosion in a wide range of environments and in many different areas of the world over the past 20 yr. However, the existing calibration procedures commonly used for deriving quantitative estimates of soil redistribution rates from 137 Cs measurements …
Cesium-137 activity according to soil horizon for five erosion phases at the three Clark County Sites. SLI, MOD, SEV, DEP, and UNE refer to slightly, moderately, severely, deposition, and uneroded ...
The caesium-137 contents of soil profiles have been used to estimate soil erosion losses from different topographic and land use conditions at Lishi, Shanxi Province, and Luochuan, Shaanxi Province. At uncultivated sites the caesium-137 has accumulated in the upper soil profile, whilst it has been mixed within the plough layer of cultivated soils.
The caesium-137 contents of soil profiles have been used to estimate soil erosion losses from different topographic and land use conditions at Lishi, Shanxi …
The spatial soil erosion patterns predicted by 137 Cs and the WEPP model were vastly different. For 137 Cs-predicted erosion redistribution, net soil loss occurred between 0 and 175 m with the maximum rate at 55 m, while sediment deposition appeared between 175 and 200 m with the maximum rate at 185 m. Net soil loss rates showed a …
Cesium-137 is readily adsorbed by clay minerals and organic matter in soil 4 and can be ... Takenaka, C. & Onda, Y. 137 Cs loss via soil erosion from a mountainous headwater catchment in ...
Cesium-137 is often used in scientific research also. For example, cesium tends to stick to particles of sand and gravel. This fact can be used to measure the speed of erosion in an area. Cesium-137 is injected into the ground at some point. Some time later, a detector is used to see how far the isotope has moved.
Most {sup 137}Cs movement in the environment is by physical processes; therefore, {sup 137}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.
In the last few decades, the use of environmental radionuclides, particularly caesium-137 (137 Cs), represented one of the most valid methods for estimating soil …
Cesium-137 is a radioactive fallout isotope that is strongly adsorbed by soil particles and has been used by numerous researchers to estimate soil erosion and deposition. In this study, background or baseline levels of /sup 137/Cs on native, noneroded soils in southern Saskatchewan are presented.
A geochemical properties finger method indicated that the ratio of the inter-gully erosion from cropland to gully erosion was 0·46:0·54 during the investigated period of 31-year period. Our results suggest that the 137 Cs technique cannot be directly used in the study catchment. Gully erosion is the main type of soil erosion that ...
Most 137 Cs movement in the environment is by physical processes; therefore, 137 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.
@misc{etde_7034359, title = {Soil erosion of agricultural land in Western Australia estimated by caesium - 137} author = {McFarlane, D J, Loughran, R J, and Campbell, B L} abstractNote = {The caesium-137 technique was used to estimate net soil loss from 10 hill slopes in the agricultural area of Western Australia. The gravel fraction of …
Key Words: black soil, cesium-137 (137Cs), Northeast China, quantitative models, soil erosion Cesium-137 (137Cs), a man-made product resulting from thermonuclear weapons testing with a half- life of 30.17 years, has been widely applied to soil erosion studies as a tracer technique (Collins et ai, 2001; Zhang et a/., 2004; Fang et …
In the last few decades, importance was given to the use of cesium-137 (137 Cs) as radioactive tracer to estimate soil erosion rates. The 137 Cs technique is linked to the global fallout of bomb-derived radiocesium which occurred during a period extending from the mid 1950s to the late 1970s. Materials and methods
The world-wide fallout of 137 Cs associated with the nuclear weapon tests during the 1950s and 1960s have provided a valuable man-made tracer for studies of soil erosion and sediment delivery (Ritchie et al., 1974), which can be used to study the difference of soil erosion in different aspects and positions.
Radioactive fallout 137 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 137 Cs movement in the environment is by physical processes; therefore, 137 Cs is a unique tracer for studying erosion and sedimentation. …
@article{osti_931512, title = {Cesium-137 in the Environment: Radioecology and Approaches to Assessment and Management (NCRP Report No. 154)}, author = {Whicker, F W and Garten, Jr, Charles T and Hamby, D M and Higley, K A and Hinton, T G and Kaplan, D I and Rowan, D J and Schreckhise, R G}, abstractNote = {The overall …
After applying conventional methods to fight soil erosion, Tunisia is using cesium-137 (137 Cs) to measure their efficiency.The innovative program is fitting for a country where desertification ...
