C - Lublin

SPATIAL DISTRIBUTION OF SELECTED SOIL PHYSICAL AND
CHEMICAL PROPERTIES
Usowicz B, Hajnos M., Sokołowska Z., Józefaciuk G.,
Bowanko G., Kossowski J.
Basic soil properties are documented on maps of different scales and degree of
generalization, and in databanks. From these one can see different variability of
soil properties on a given area. Despite the heterogeneity of soil on a field scale
may be high, this is frequently neglected not only by farmers, but also by scientists.
As a rule the soil in a single field is considered to be homogeneous so one-point
measurements are used for determination of its properties and uniform agricultural
practices are applied, as well. In general, least knowledge on soil spatial variability
has been collected in respect of its mathematical-physical description, and in
respect of its natural and anthropogenic components.
In this work spatial variability of selected soil physicochemical properties was
studied on an area of a whole commune (Trzebieszów, Lublin voivodship) and on a
single field. The statistic and geostatistic analysis including estimation of spatial
distribution and estimation error of soil granulometric composition and pH are
presented.
MATERIALS AND METHODS
Trzebieszów commune is located on a flat landscape of denivelations rarely
exceeding 10 m, with a few shallow valleys of flooding rivers. The lowland is
mostly built from outwash material, with loose sands to low clayey sandy soils [4].
The mean annual temperature is 7,3 o C; the mean temperature of the warmest
month (July) is 17,7 o C, and of the coldest one (January) is –3,5 o C. The annual
rainfall is 537 mm, 64% of which comes during vegetation period (IV-IX).
The soils were sampled in summer from randomly located points (commune)
and regular network points (field), that is shown in Fig. 1. Analysis of
granulometric composition was performed using areometrical-sedimentation
method and of the pH (H 2 O and KCl) potentiometrically.
Both for the commune and the field areas the basic statistical parameters
were estimated: mean value, standard deviation, coefficient of variability (CV),
skewness and kurtosis. Spatial characteristics of the studied soil features was
performed using geostatistical methods. Exsperimental semivariogram − γ(h) for
the distance h was calculated from the equation [4, 5]:
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