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931.
This study uses evidence for the long-term (35 years) pattern of soil redistribution within two agricultural fields in the UK to identify the relative importance of tillage and overland flow erosion. Spatially distributed long-term total soil redistribution data for the fields (Dalicott Farm and Rufford Forest Farm) were obtained using the caesium-137 (137Cs) technique. These data were compared with predicted patterns of soil redistribution. Recent studies have demonstrated that the redistribution of soil by tillage may be described as a diffusive process. A two-component model was, therefore, developed which accounts for soil redistribution by both overland flow and diffusive processes. Comparison of the predicted patterns of overland flow erosion alone with the observed (137Cs-derived) data indicated a poor agreement (r2 = 0.17 and 0.11). In contrast, a good agreement exists between the predicted pattern of diffusive redistribution and the observed data (r2 = 0.43 and 0.41). These results give a clear indication that diffusive processes are dominant in soil redistribution within these fields. Possible diffusive processes include splash erosion, soil creep and tillage. However, the magnitude of the diffusion coefficients for the optimum predicted pattern (c. 350–400 kg m−1 a−1) demonstrates that tillage is the only process capable of explaining the very significant soil redistribution which is indicated by the 137Cs data. Consideration is given to the implications of these results for both soil erosion prediction and landscape interpretation. 相似文献
932.
933.
Solar System Research - The paper presents the results of studying the dynamic structure of near-Earth orbital space in the regions of orbital resonances 1 : 4, 1 : 6, and 1 : 8 with the speed of... 相似文献
934.
935.
Astronomy Letters - Based on published data, we have produced a sample of 256 radio sources whose trigonometric parallaxes and proper motions were measured by VLBI. This sample contains Galactic... 相似文献
936.
Astronomy Letters - Based on an analysis of the dynamic spectra for solar flares in the meter wavelength range obtained with the ground-based Radio Solar Telescope Network, we consider the... 相似文献
937.
Sadovsky I. N. Kuzmin A. V. Khapin Yu. B. Kozlova T. O. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(12):1741-1750
Izvestiya, Atmospheric and Oceanic Physics - The MIRS microwave radiometer–spectrometer is described. The instrument is being developed using a conceptual design that was the first stage of... 相似文献
938.
Oceanology - Abstract—The paper contains original data on the rock-forming and rare element compositions in the Pliocene–Holocene alkaline basaltoids of the Tsushima Basin Sea of Japan,... 相似文献
939.
Gordeev V. V. Dara O. M. Alekseeva T. N. Kochenkova A. I. Boev A. G. Lokhov A. S. Belorukov S. K. 《Oceanology》2020,60(3):384-392
Oceanology - The paper presents the first results of a study of seasonal variations in the grain size distribution and mineral compositions of suspended particulate matter (SPM) of the Northern... 相似文献
940.