![Vertical migration of ^6^0Co, ^1^3^7Cs and ^2^2^6Ra in agricultural soils as observed in lysimeters under crop rotation [An article from: Journal of Environmental Radioactivity]](https://www.ebooknetworking.net/books/noimage.jpg)
Vertical migration of ^6^0Co, ^1^3^7Cs and ^2^2^6Ra in agricultural soils as observed in lysimeters under crop rotation [An article from: Journal of Environmental Radioactivity]
Book Details
PublisherElsevier
ISBN / ASINB000RR3TAO
ISBN-13978B000RR3TA3
AvailabilityAvailable for download now
Sales Rank99,999,999
MarketplaceUnited States 🇺🇸
Description
This digital document is a journal article from Journal of Environmental Radioactivity, published by Elsevier in 2005. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
In most studies quantifying the migration parameters - apparent migration velocity and apparent dispersion coefficient - of radionuclides in the soil by model calculations, these parameters are determined for undisturbed soils. For soils disturbed by ploughing, however, no such data are available in the literature. Therefore, in the present study, the migration parameters of ^1^3^7Cs, ^6^0Co and ^2^2^6Ra were estimated for ploughed soils by means of a convection-dispersion model. The depth distributions of the radionuclides were determined in four lysimeters (area: 1m^2, depth of soil monolith: 0.75m) filled with artificially contaminated soils of different types in July 1990. The lysimeters were cropped with agricultural plants. The soil in each lysimeter was ploughed manually once a year until 1996 (plough depth 20cm). In July 1999, soil samples were collected from three pits in each lysimeter. The depth distributions of all radionuclides proved to be very similar in each soil pit. The spatial variability of the depth distributions of a given radionuclide within the lysimeters was about the same as their variability between the four lysimeters. Evaluation of the migration parameters revealed that the convective transport of the radionuclides was always rather small or even zero, while the dispersive transport caused a ''melting'' process of the initially sharp activity edge at the lower border of the Ap horizon. These results are explained by the high evapotranspiration (80-90% of the total precipitation plus irrigation) and the small amounts of seepage water during the observation period of 9 years.
Description:
In most studies quantifying the migration parameters - apparent migration velocity and apparent dispersion coefficient - of radionuclides in the soil by model calculations, these parameters are determined for undisturbed soils. For soils disturbed by ploughing, however, no such data are available in the literature. Therefore, in the present study, the migration parameters of ^1^3^7Cs, ^6^0Co and ^2^2^6Ra were estimated for ploughed soils by means of a convection-dispersion model. The depth distributions of the radionuclides were determined in four lysimeters (area: 1m^2, depth of soil monolith: 0.75m) filled with artificially contaminated soils of different types in July 1990. The lysimeters were cropped with agricultural plants. The soil in each lysimeter was ploughed manually once a year until 1996 (plough depth 20cm). In July 1999, soil samples were collected from three pits in each lysimeter. The depth distributions of all radionuclides proved to be very similar in each soil pit. The spatial variability of the depth distributions of a given radionuclide within the lysimeters was about the same as their variability between the four lysimeters. Evaluation of the migration parameters revealed that the convective transport of the radionuclides was always rather small or even zero, while the dispersive transport caused a ''melting'' process of the initially sharp activity edge at the lower border of the Ap horizon. These results are explained by the high evapotranspiration (80-90% of the total precipitation plus irrigation) and the small amounts of seepage water during the observation period of 9 years.
