Specific surface area and microstructure of the surface of soil solid substrates of different genesis-Reference-Cited by-同舟云学术

Specific surface area and microstructure of the surface of soil solid substrates of different genesis

Published:2024-03-25 Issue:118 Volume: Page:167-187
ISSN:2312-4202
Container-title:Dokuchaev Soil Bulletin
language:
Short-container-title:DSB

Author:

Shiroyan M. M.¹^ORCID,Umarova A. B.¹^ORCID,Fedotova A. V.²,Butylkina M. A.¹

Affiliation:

1. Lomonosov Moscow State University

2. Federal Scientific Center for Agroecology, Integrated Land Reclamation and Protective Afforestation of the Russian Academy of Sciences

Abstract

The sorption characteristics of sand, peat, the arable layer of Moscow urbanozem and a mixture of these substrates were studied in conjunction with the surface topography of their solid phase, studied by scanning electron microscopy (SEM). The arable layer has the greatest ability to absorb nitrogen, and the peat substrate showed very low values of the sorbed gas. A different picture of the mutual arrangement of substrate sorption isotherms is observed when water vapour is used as a sorbing gas. Peat is distinguished by high values of sorbed moisture in the entire studied range of relative humidity. This leads to differences in the ranking of substrates by specific surface area in descending order of its values. So, the specific surface area by water sorption in the series: peat / arable layer / mixture / sand was: 420 / 72 / 45 / 4 m2/g, respectively. The given surface was ranked according to nitrogen sorption in a different sequence: 8.31 / 2.41 / 1.45 / 0.55 for the series: arable layer, mixture, peat and sand, respectively. The analysis of microstructural characteristics by the SEM method at various magnifications revealed the most developed, rough surface in the arable layer. It turned out to be geometrically the most diverse, even at magnification of ×20 000. The variety and heterogeneity of the relief of the interface of the phases leads to the appearance of hysteresis of the sorption/desorption curves. Its severity in the range of nitrogen vapor concentration in which hysteresis is detected, and in the maximum width of the hysteresis loop, also turned out to be the most significant in the arable layer. The very low nitrogen specific surface of peat, which is close to a sandy substrate, is associated with the presence of organic films draping and leveling the surface of peat particles, which was revealed by analyzing images obtained by scanning electron microscopy. The sorption of water showed their high hydrophilicity, which led to high values of substrate humidity in the entire studied range of relative humidity.

Publisher

V.V. Dokuchaev Soil Science Institute

Reference32 articles.

1. Vityazev V.G., Chizhikova N.P., Shevchenko A.V., Udel'naya poverkhnost' i sostav mineralov ilistykh fraktsii podzolistykh pochv (Specific surface area and mineral composition of silty fractions of podzolic soils), Izvestiya TSKhA, No. 3, 1983, pp. 98–104.

2. Voronin A.D., Strukturno-funkcional'naja gidrofizika pochv (Structural and functional soil hydrophysics), Moscow: MGU, 1984, 204 p.

3. Voronin A.D., Vityazev V.G., K otsenke velichiny vneshnei i vnutrennei udel'nykh poverkhnostei tverdoi fazy pochv po izoterme desorbtsii parov vody (To estimate the magnitude of the external and internal specific surfaces of the solid phase of soils by the isotherm of water vapor desorption), Pochvovedenie, 1971, No. 10, pp. 50–57.

4. Rukovodstvo po ekspluatatsii programmnogo obspecheniya 3P meso 222. Analizator udel'noi poverkhnosti i poristosti. Versiya PO 20.05.xx (Operating instructions for the 3P meso 222 software. Specific surface area and porosity analyzer. Software version 20.05.xx), 3P Instruments, GmbH&Co, KG, 2021.

5. Sapozhnikov P.M., Udel'naya poverkhnost' pochvy, ee izmenenie pri pochvoobrazovatel'nykh protsessakh i svyaz' s fizicheskimi svoistvami: Avtoref. dis. … k. s.-kh. n. (The specific surface area of the soil, its change during soil formation processes and the relationship with physical properties, Extended abstract of cand. agric. sci. thesis), Moscow, MGU, 1982, 28 p.