Gamma-ray computed tomography as a tool to evaluate porosity changes along depth for surface crusted soils

• Autorzy: Pires L. F. , Bacchi O. O. S. , Reichardt K. , Dias N. M. P.
• Języki publikacji: EN

Abstrakty

EN

Assessment of changes in porosity (ö) along depth for soils with surface crusting is difficult because conventional soil physical investigation tools are destructive and usually require a long period of time for preparation and analysis of the samples. Computed tomography (CT) has frequently been used as a method to evaluate soil structure in a nondestructive, sensitive, and rapid manner. CT data can be used for measuring at a millimetric scale changes in ö along depth for soils with surface crusting. The main objective of this work was to investigate the sensibility of the gamma-ray CT to assess soil structural changes along depth in samples presenting structural crust. CT images were taken with a first generation scanner of 1.14 mm resolution along eight different soil layers within the 0 28 mm depth. Porosity increased along depth up to the 14 17.5 mm layer. Through the analysis of the ö distribution of each layer it was possible to show that the sealed surface layer presented ö values of approximately 30%, while the other layers were greater than 30% up to 60% (macropore regions). The sealing crust thickness was estimated to be in the range of 2.3 3.5 mm.

Słowa kluczowe

EN

gamma-ray attenuation; soil density; soil structure; soil surface sealing; 241 Am; applied nuclear physics; gamma tomography

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2007
• Tom: Vol. 52, nr 3
• Strony: 125--131
• Opis fizyczny: Bibliogr. 30 poz., rys.

Twórcy

autor

Pires L. F.

autor

Bacchi O. O. S.

autor

Reichardt K.

autor

Dias N. M. P.

• Department of Physics, State University of Ponta Grossa, UEPG,C. E. P. 84.030-900, Ponta Grossa, PR, Brazil and Center for Nuclear Energy in Agriculture, The University of Săo Paulo, C. P. 96, C. E. P. 13.400-970, Piracicaba, SP, Brazil, Tel.: 55 42,

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