Acta Stereologica Acta Stereologica -  Volume 12 (1993)  Number 2 - Proceedings of the sixth European congress for stereology - Part one - Dec. 1993 

What kind of information can be extracted from manually segmented two-dimensional sections of soil macrostructure?

Dietrich Werner
Landwirtschaftliche Untersuchungs- und Forschungsanstalt Thüringen, Naumburger Straβe 98, Jena 9 – Zwätzen, Germany
František Doležal
Výzkumný ústav meliorací a ochrany půdy, Žabovřeská 250, 156 27 Praha 5 – Zbraslav, Czech Republic 

Abstract

The effect of heavy agricultural machinery upon soil macrostructure was investigated by several methods complementing each other. One of them was the evaluation, both qualitative and quantitative, of thin impregnated soil sections of the size about 60 x 80 mm. The quantitative evaluation was based on manually drawn contours of soil pores (≥ 70 microns) on a sheet of graph paper onto which the magnified image (15 x) of the soil section was projected using polarized light. The quantification consisted in measuring the intercept lengths in the pores, using systems of parallel testing lines. Some sample statistics of the intercept length distribution were related to other soil properties of mechanical and hydraulic nature; at the same time, the morphometric data yielded supplementary information about the soil macropore structure that could not be obtained in other way. More recently, an attempt at manual re-evaluation of the old images was undertaken in order to explore whether more information can be extracted from them and to suggest algorithms for their automated processing. Because of the lacking spatial information, the effort was focused on evaluating the planar images as such. Anisotropy was not considered. Additional information is contained, in particular, in the distribution of the radial contact distances from a random point in matrix to the nearest macropore. On the contrary, the methods based on treating pores as individual particles are probably of little use.

Keywords : macropores, sections, soil, structure

To cite this article

Dietrich Werner & František Doležal, «What kind of information can be extracted from manually segmented two-dimensional sections of soil macrostructure?», Acta Stereologica [En ligne], Volume 12 (1993), Number 2 - Proceedings of the sixth European congress for stereology - Part one - Dec. 1993, 249-254 URL : https://popups.ulg.ac.be/0351-580x/index.php?id=1619.