Landscapes Forest and Global Change - ESA - Escola Superior ...

N.S. Evseeva & Z.N. Kvasnikova 2010. Ecological aspects of soils deflation development in agrolandscapes
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than 1000 km) The dust composition was made up of particles less than 0,25 mm in 87,4%
cases and there were particles of 0,25-0,05 mm in size in 12,6% cases. According to some
approximate data, about 20 mln tons of humus, about 1 mln of nitrogen, 240 th. tons of calium
and more than 60 th. tons of phosphorus were carried to the territory of the Tomsk region
together with dust.
The local aeol processes are those ones which develop in the range of landscape areas on the
earth’s surface (inter-river areas, terraces) which have no natural vegetation (plowland, felling
sites, the areas of oil and gas extraction).
The aim of the present paper is to investigate the modern local aeol processes in the
agrolandscapes which developed during the cold season of the year (October-April) from 1989
to 2008. The major factors of the aeol processes development of the investigated region have
been considered by N.S. Evseeva, Z.N. Kvasnikova, N.V. Osintseva, T.V. Romashova, 2001;
N.S. Evseeva, V.N. Slutsky, 2005 in their works.
2. Initial data and the methods of investigation
In order to reveal the intensity and the dynamics of the local aeol processes development the
authors have done a great deal of work. They performed repeated microscale snow survey in the
vicinity of the Luchanovo station in the Tom – Yaya interriver area from 1989-2008. They also
made route observations, selected snow samples but of the snow thickness and its surface as
well using the support profiles; they did a three-time snow water filtering. The authors also dealt
with the drying and weighing of the solid sediment, analyzed the granulometric and chemical
composition of the aeol deposits. There exist various techniques of determining deflation
intensivity and accumulation. They determined the deflation intensity according to the formula
stated by M.E. Belgibaev (1972):
h=V/S,
where h is the depth of soils blowing out, m; V – the volume of the material blown out, m 3 ; S –
area of dust collection, m 2 .
The aeol accumulation intensity was estimated according to the aeol deposits in snow as well as
aeol particles accumulation per a unit of square. According to the method developed by E.M.
Lyubtsova (1994) the accumulation of aeol particles is as follows: weak (less than 50 g/m 2 ),
moderate (50-100 g/m 2 ), average (100-200 g/m 2 ), strong (200-500 g/m 2 ), very strong (500-1000
g/m 2 ).
3. Results
Aeol processes in agrolandscapes are divided into destructive and accumulative; and they are of
an uneven and intermittent character. The destructive processes during the cold season of the
year are represented by deflation having its centre development. Wind formed slopes of microand
nano-relief elevations of a plowland as well as furrows in the process of deep autumn
plowing are subjected to deflation. Researchers observe that the Siberian soil cover is vulnerable
to strong winds because the soil agregate content which is less that 1 mm reaches 40-88%, i.e. it
is characterized by a strong turning to dust process. The antideflation stability of grey wood and
soddy-podzolic and ashen-gray plowland soil determined by G.A. Larionov technique (1993) is
not mainly high, and it varies in the range of 24-57 and 10-49. Soil particles blown out of
deflation centres are carried by winds over various distances and deposited on plowland snow
surface, in shelterbelts located not far from the plowing areas.
Besides, fine particles which are carried by windy flows from other regions are accumulated in
snow. According to some observations made from 2000-01, 2002-03, 2003-04 and 2004-05,
their weak development was seen in 2005-06, 2006-07 (28%), and their average development
occurred in 2007-08 (1%).
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.