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Soil deflation analyses from wind erosion events

100%

Lackoova L., Urban T., Kondrlova E., Kozlovsky Dufkova J.

Acta Scientiarum Polonorum. Formatio Circumiectus

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2015

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tom 14

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nr 3

There are various methods to assess soil erodibility for wind erosion. This paper focuses on aggregate analysis by a laser particle sizer ANALYSETTE 22 (FRITSCH GmbH), made to determine the size distribution of soil particles detached by wind (deflated particles). Ten soil samples, trapped along the same length of the erosion surface (150–155 m) but at different wind speeds, were analysed. The soil was sampled from a flat, smooth area without vegetation cover or soil crust, not affected by the impact of windbreaks or other barriers, from a depth of maximum 2.5 cm. Prior to analysis the samples were prepared according to the relevant specifications. An experiment was also conducted using a device that enables characterisation of the vertical movement of the deflated material. The trapped samples showed no differences in particle size and the proportions of size fractions at different hourly average wind speeds. It was observed that most of particles travelling in saltation mode (size 50–500 μm) – 58–70% – moved vertically up to 26 cm above the soil surface. At greater heights, particles moving in suspension mode (floating in the air; size < 100 μm) accounted for up to 90% of the samples. This result suggests that the boundary between the two modes of the vertical movement of deflated soil particles lies at about 25 cm above the soil surface.

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Applicability of unidimensional soil particle size distribution characteristics to plant ecology

80%

Czerwinski M., Kaliszewski G.

Acta Agrophysica

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2013

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tom 20

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nr 1

The subject of the research was unidimensional indices (characteristics) of mineral soil particle size distribution: mass fractal dimension of soil particle size distribution, grain-size distribution index, mean particle diameter and the product of the two latter. Among the four above-mentioned indices, the three former are known from previous studies and the latter was proposed by the authors. The work is an attempt to answer the question which of these indices best describes the granulometric composition of mineral soils as a factor differentiating the species composition of vegetation. The experimental area was a one hectare fallow composed of soils of five different tex-tural classes. The ruderal plant cover of the fallow was mechanically destroyed and several dozen semi-natural grassland species were sown on bare soil. The seeds were thoroughly mixed and evenly distributed over the entire experimental area. Then, 39 permanent plots were regularly deployed across the experimental area. In the following year, the frequency of the emerging seedlings and juveniles of the sown plant species was estimated and the texture of the soil surface layer was ana-lysed in the permanent plots. Statistical analysis performed by fuzzy set ordination method indicated that the product of grain-size distribution index and mean particle diameter is the most appropriate unidimensional granulometric characteristic of the soil particle size distribution as a plant commu-nity assembly driver.

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Sily oddzialywan miedzy czastkami gleb przez interfaze wodna

70%

Hajnos M.

Acta Agrophysica

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1999

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tom 22

53-58

Na podstawie równania Laplace'a wyprowadzono zależność między siłą działającą pomiędzy dwoma ziarnami materiału glebowego przez fazę wodną, a składowymi swobodnej energii powierzchniowej. Stwierdzono zależność wartości sił oddziaływań od zawartości Corg w badanych glebach. Dla gleb o zawartości Corg powyżej 40% wartości tych sił są ujemne. Słowa kluczowe: siły adhezji, kąt zwilżania, składowe swobodnej energii powierzchniowej.

Ograniczanie wyników

2 Acta Agrophysica

1 Acta Scientiarum Polonorum. Formatio Circumiectus

1 Czerwinski M.

1 Hajnos M.

1 Kaliszewski G.

1 Kondrlova E.

1 Kozlovsky Dufkova J.

1 Lackoova L.

1 Urban T.

1 2015

1 2013

1 1999

Soil deflation analyses from wind erosion events

Applicability of unidimensional soil particle size distribution characteristics to plant ecology

Sily oddzialywan miedzy czastkami gleb przez interfaze wodna