This monograph presents findings from a long-term study designed to explore an effect of accelerated erosion on soil properties in a loessial landscape and ways of soil amelioration with the use of synthetic polymers. Soil erosion results in heavy differentiation of a soil cover with natural pedons being reduced or overbuilt. Both eroded and colluvial soils differ from non-eroded soils not only in morphological features but also in particle-size distribution, organic matter content and plant nutrients.

Slight, moderate and severe erosion has an adverse effect on physical properties of Haplic Luvisols developed from loess. In Ap horizons of eroded soils developed from Bt horizon, clay content and bulk density are on the increase whereas the content of organic matter, content of water-stable aggregates, field water capacity and retention of water useful for plants decrease, and porosity, air capacity and air permeability deteriorate. By contrast, in very severely eroded soils whose Ap horizons developed from carbonate loess, pore-size distribution, field water capacity and retention of water useful for plants are favourable and comparable to those in non-eroded soils. Colluvial soils are also characterized by advantageous particle-size distribution, organic matter content, aggregate water stability, and by water-air properties similar to (or even somewhat better than) those of non-eroded soils.

As a result of soil erosion, grain yields of spring and winter wheat, corn and spring barley were lower by 5.5-39.7%. By comparison, grain yields from colluvial soils were close to (or even higher than) those from non-eroded soils.

Unstable aggregate structure of eroded soils contributes to surface crust forming and further water erosion during intense runoffs. As the soils potentially rich in nutrients for plants, they require restoration of water-stable aggregate structure and improvement in water and air properties. Traditional methods for ameliorating soil physical properties include application of high doses of organic fertilizers, NPK fertilization, liming and crop rotation with an increased share of papilionaceous plants and grasses. In order to supplement traditional methods, synthetic polymers, resistant to microbiological decomposition, non-toxic and environment-friendly, may be added to soil.

Field experiments showed that gel-forming polymers: Viterra, Stockosorb, Hidroplus and AgroHydroGel as well as hydrophobic polymers: Terravest 801 and PVAC improved aggregate size distribution and aggregate water stability in the arable layer of eroded Haplic Luvisols developed from loess. Vittera hydrogel applied in doses of 0,5 gּkg-1 and 1 gּkg-1 of dry soil mass and the other polymers applied in 1 gּkg-1 and 2 gּkg-1 of dry soil mass proved most effective. Synthetic polymers had also a positive impact on bulk density, total porosity, water capacity, retention of water useful to plants and air permeability in eroded soils. The use of Vittera had a beneficial effect on exchangeable and available potassium in soils. The polymer application caused increases in grain yields of spring wheat grown on slightly, moderately and very severely eroded soils. However, due to high costs of their production, the wider use of gel-forming polymers in agriculture is not economically viable.