NON-TRADITIONAL AMELIORANTS - Fertilizers: Components, Uses in Agriculture and Environmental Impacts - page 206

Figure 6. Effect of bentonite clay ploughed in the 0-5 cm soil layer on the content exchangeable pota-
ssium in the arable layer, % deviations from control (no ameliorant).
Bentonite clay, stirring it with the soil layer 0-20 cm, more efficiently has absorbed the
potassium ion. This has promoted to increase the number of exchangeable potassium in the
arable horizon by 4-15 % compared with the control (without ameliorant) and protected him
from washing away down the profile. The process of absorption of potassium ion by
montmorillonite observed by other researchers (Gorbunov, 1978; Goryachev, 2012; Lgotski,
1979; Mattson, 1934).
The obtained data on the effect of bentonite clay on the nitrate nitrogen content are
contradictory. Based on the available number of observations is not possible to draw definite
conclusion, but other authors proved the possibility of absorption of this ion (Gorbunov, 1978;
Iryanova, 1987).
E FFECT OF B ENTONITE C LAY ON A GROPHYSICAL P ROPERTIES
One of the basic indicators of soil fertility are an agrophysical properties, which often
limit the productivity of crops. Entering bentonite clays had a positive effect on these
properties, especially on the structure of the arable layer (Table 1). The best indicator of
dispersity factor, which characterizes the durability of the microstructure (the higher the
dispersity factor, the less durable microstructure of the soil), was observed in the variant with
mixing bentonite clay with a soil layer of 0-5 cm and was below that variant with the entering
its in the soil layer 0-20 cm by 8.1%. The mixing bentonite clay with a soil layer of 0-5 cm
increased the aggregative index of the arable layer by 5.2 % compared to the deep placement
of this ameliorant and by 10.6% compared with the control (without ameliorant). Increasing
the aggregative index means improving the water stability of the structure.