Soil acid-base buffering in the step agriculture lands

Modern studies of chernozem soils in the northwestern Black Sea region have shown intense dehumification due to disruption of biogeochemical cycles caused by anthropogenic removal of organic matter and associated biophile elements. At former time, the humus zoning was typical for southern chernozems and now we noted the smoothing of this zoning. Acid-base buffering has a significant role in counteracting degradation processes, the buffering parameters could be integral indicators of soil chemicals balance. We studied the automorphic soils (arable chernozems) of the northwestern Black Sea region, their humus state, particle size distribution, and acid-base buffering parameters. We studied ordinary modal and micellar-carbonate chernozems on arable land and 40-year-old fallows, southern chernozems removed from irrigation 15 years ago and southern carbonate chernozems of the second floodplain terrace of the Danube River. We determined the neutralization index, degree of buffering capacity in the acid and alkaline ranges, equilibrium coefficient, and sodium absorption ratio to characterize the acid-base buffering. The studied soils belong to stable buffer agriculture lands by their acid-base buffer ability. We determined that soils have the parameters of chernozem type: low humus content, humate and humate-fulvate type of humus, average content of insoluble residue, high degree of humification, heavy-medium loam particle size distribution, and neutral soil solution. The acid-base buffer capacity is characterized by average values, the buffer capacity in the acid interval increases with depth, while decreases in the alkaline interval. We revealed a significant correlation between the ability to counteract the acid load and the content of physical clay. We believe that the agricultural use of southern chernozems leads to a decrease in soil resistance to acidification.

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SILICON CONTENT, PHYSICAL AND CHEMICAL PROPERTIES OF SOILS OF THE KHMELNYTSKY REGION OF UKRAINE

Visnyk of Taras Shevchenko National University of Kyiv Geology ◽

10.17721/1728-2713.90.12 ◽

2020 ◽

pp. 85-90

Author(s):

O. Tonkha ◽

O. Bukova ◽

O. Pikovska ◽

I. Fedosiy ◽

O. Menshov ◽

...

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Humus Content ◽

Chemical Properties ◽

Arable Soils ◽

Silicon Compounds ◽

Exchangeable Acidity ◽

Chemical Properties Of Soils ◽

Physical And Chemical

Silicon plays the significant role in the growth and development of plants, their resistance to stress conditions. However, there is limited research on the content of various forms of silicon in soils, the relationship with soil cations, which is particularly relevant in the context of intensive agriculture and climate aridization in Ukraine. The purpose of the present study was to determine the content of silicon compounds of different mobility in the arable soils of the Khmelnytsky region, the spatial variation of these parameters, and to detect the dependence between the content of silicon compounds and soil particle size. The study was performed at the area of LLC "Lotivka Elit" of Shepetivka district of Khmelnitsky region in field crop rotation. We determined for soil samples: particle size distribution and content of fractions of granulometric elements of different sizes, pH of salt extraction (1,0 M KCl solution), humus content, calcium and magnesium exchangeable compounds by extraction with 1,0 M KCl solution. The results showed that the content of silicon compounds in soils depends on the particle size distribution of soil, the value of exchangeable acidity, humus content, and the composition of exchangeable cations.

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Organic Carbon and Particle-Size Distribution in the Littoral Bottom Sediments of the Laspi Bay (the Black Sea)

Morskoy gidrofizicheskiy zhurnal ◽

10.22449/0233-7584-2020-3-287-299 ◽

2020 ◽

Vol 36 (3) ◽

Author(s):

N. A. Orekhova ◽

E. I. Ovsyany ◽

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Keyword(s):

Particle Size ◽

Organic Carbon ◽

Particle Size Distribution ◽

Size Distribution ◽

Black Sea ◽

Bottom Sediments ◽

The Black Sea

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Evaluation of Silver Phytotoxicity on Soils of Different Stability: Brown Forest, Chernozem and Sierosands

UNIVERSITY NEWS. NORTH-CAUCASIAN REGION. NATURAL SCIENCES SERIES ◽

10.18522/1026-2237-2020-3-107-112 ◽

2020 ◽

pp. 107-112

Author(s):

N.I. Tsepina ◽

T.V. Minnikova ◽

S.I. Kolesnikov ◽

K.Sh. Kazeev

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Toxic Effect ◽

Forest Soil ◽

Size Distribution ◽

Humus Content ◽

Ordinary Chernozem ◽

Soil Reaction ◽

Brown Forest Soil ◽

Radish Root

The effect of silver pollution on the phytotoxicity of soils of varying degrees of resistance: chernozems, sierosands and brown forest soils was investigated. A direct relationship was observed between the concentration of the element in the soil and the length of the radish roots. At a silver concentration of 10 mg/kg, the highest toxicity was established on sulphurous sand and brown forest soil. A dose of 100 mg/kg had the greatest inhibitory effect on the length of the roots of radishes grown on ordinary chernozem, sierosands, and brown forest soil at 17, 24, and 29 % of the control, respectively. According to the degree of resistance to silver pollution, according to the radish root length indicator, the studied soils form the following series: ordinary chernozem (90) ≥ sierosands (88) > brown forest soil (81). The toxic effect of silver depends on the concentration of the element in the soil, the particle size distribution, the reaction of the soil environment and the content of organic matter in the soil. The greatest resistance of common chernozem to silver contamination is due to the particle size distribution, high humus content (3.7 %) and neutral alkaline-acid conditions (pH = 7.8). The light particle size distribution of the sierosands does not provide a sufficient absorption capacity for fixing silver in the soil. Brown forest soil is most sensitive to silver, as it has an acidic soil reaction (pH = 5.8), in which this element is mobile and has a toxic effect on the radish root system.

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