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Aim of the study focused on evaluation of SUBSTOR – Potato model and its utilization in potato grows management in the Czech Republic. The experimental field used for the model evaluation was located in Žabčice – South Moravia region with altitudes of 179 meters above the sea level. Tuber yield served as reference for the model evaluation. Nine years experimental data set (1994–2002) was used for the model validation. Rosara cultivar represented very early growing potato, Karin cultivar depic­ted early growing potato (Solanum tuberosum L.) in the experiment. Comparison between observed and simulated tuber yields presented the evaluation process of SUBSTOR – Potato model. Tuber yields simulated by the model showed excellent accuracy (R2 = 0.97) for Rosara cultivar, but only for four of tested years (1997, 1998, 1999 and 2002). Karin cultivar matched lower value (R2 = 0.43). The model tended to underestimate the tuber yield for non seasonable conditions (i.e. dry years – low amount of precipitation and its disordered distribution during the growing season or higher mean air temperature) and showed the sensitivity to selected cultivars. Study proved SUBSTOR – Potato model as sui­table for utilization in potato management; however, potential differences might be expected while using the model under extreme weather conditions.

Evaluation of the vulnerability of agricultural land by water erosion, including the erosion control measures design, was done using the geographic information systems (GIS) on example of the cadastral area Rovečné, the Czech Republic. Analytical operations that lead to evaluation of the basic runoff and especially erosion rates according to the Universal Soil Loss Equation (USLE) were made in ArcGIS 10 Desktop, the software product ArcInfo using a set of integrated software applications ArcMap, ArcCatalog and user interface ArcToolbox, and also using programs LS-converter and USLE2D. The potential loss of soil by water erosion was determined before and after erosion control measures design. The proposed measures should improve the current situation and contribute to preservation of agricultural activity in this area in a form close to the current situation.Key words: cadastral area Rovečné, water erosion, USLE, ArcGIS, LS-converter, USLE2DSouhrn: Vyhodnocení ohroženosti zemědělské půdy vodní erozí včetně návrhu protierozních opatření za využití geografických informačních systémů (GIS) je demonstrováno na příkladu katastrálního území Rovečné nacházejícího se v České republice. Analytické operace vedoucí k vyhodnocení základních odtokových a především erozních poměrů dle univerzální rovnice ztráty půdy (USLE) byly provedeny v programu ArcGIS 10 Desktop, v softwarovém produktu ArcInfo pomocí sady integrovaných softwarových aplikací ArcMap, ArcCatalog a uživatelského rozhraní ArcToolbox a dále v programech LS-converter a USLE2D. Potenciální ztráta půdy vodní erozí byla stanovena před a po návrhu protierozních opatření. Navrženými opatřeními by mělo dojít ke zlepšení stávajícího stavu a zároveň k udržení zemědělské činnosti na tomto území v podobě blízké současnému stavu.

The equation that expresses the influence of factors affecting soil aggregates breakdown, and thus wind erosion, originated from the results of laboratory simulations of soil aggregates breakdown due to low temperatures treatment, field measurements of air temperature and soil moisture, and statistical evaluation of gained outcomes. All the analyses, whether field or laboratory, were realized on three different soils from three different localities of the Bílé Karpaty Mountains foothills – Ostrožská Nová Ves, Blatnice pod Svatým Antonínkem, and Suchá Loz. The statistically significant factors, influencing the soil aggregates breakdown, were determined using multiple regression analysis and stepwise regression. Soil moisture content at time of freezing was the most significant factor affecting soil aggregates breakdown, content of soil particles < 0.01 mm was the least significant one. Based on the results of laboratory and field research there was created a map of heavy-textured soils that are vulnerable to wind erosion.

Wind erosion is the leading cause of soil degradation and air pollution in many regions of the world. As wind erosion is controlled by climatic factors, research on this phenomenon is urgently needed in soil and land management in order to better adapt to climate change. In this paper, the impact of wind erosion on the soil surface in relation to particle size distribution was investigated. Changes in percentage of sand, silt and clay fractions based on historical KPP data (1961–1970), LUCAS data base (2009), and field measurements (2016) were analysed in five cadastral areas impacted by wind erosion (Záhorie Lowlands, Slovakia). With the use of GIS tools, models of spatial distribution of sand, silt, clay and erodible fraction (EF) content were developed based on those measurements. Our findings proved that soil texture change driven by wind erosion could happen relatively quickly, and a significant proportion of soil fine particles may be carried away within a few years. The results indicate that the soil surface became much rougher over the period of more than 50 years, but also that the accumulation of fraction of the silt particles occurred in most of the areas affected by the erosive effect.