Evaluation of erosion rates in cadastral area Rovečné (Moravia) using GIS tools

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.O

Kritéria rozvoje větrné eroze na těžkých půdách v podhůří Bílých Karpat

Wind erosion, a phenomenon affecting light-textured soils primarily, occurs also on heavy-textured soils in some regions of the Czech Republic. The foothills of the Bílé Karpaty Mountains belong to the areas, where the anomaly could be found. The process of wind erosion affects the soil first of all in winter and pre-spring period, when a breakdown of soil aggregates can be observed due to low air temperatures

Influence of low temperatures on aggregate disruption of heavy clay soils

Heavy clay soils that are normally resistant to wind erosion, from study site Ostrožská Nová Ves si­tua­ted in the foothills of the Bílé Karpaty Mountains, Czech Republic, were a subject of laboratory analyses. The analyses should found out the influence of overwinter processes on disruption of soil aggregates and thus reason of vulnerability to soil loss by wind. Two overwinter processes were observed – freezing and thawing, and freeze-drying of the soil. Both processes have indicated the increasing of erodible fraction in dependence of water content of analysed soils. Exposed frozen clay soils that freeze-dries during the winter in the foothills of Bílé Karpaty, leaves soils highly erodible in late winter and early spring

Wind erosion on heavy-textured soils: calculation and mapping

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

Determination of wind erosion intensity on heavy clay soils

Wind erosion, common problem of light-textured soils, was determined on heavy clay soils in the foothills of Bílé Karpaty Mountains, Czech Republic. Soil erodibility by wind was determined from the Map of potential erodibility of soil by wind and from the calculation of potential and real soil loss by wind. All the determinations show underestimation of soil erodibility by wind on heavy clay soils, because methods that are used for this are based above all on the assessment of clay particles content and the presumption the more clay particles soil contains, the less vulnerable to wind erosion is. The potential erodibility of soil by wind is 0,09 t . ha−1 per year. The determined value does not exceed the tolerable soil loss limit 10 t . ha−1 per year for deep soils. The real average erodibility of soil by wind has the highest value 1,47 g . m−2 on November 30th, 2008. Other soil losses that do not exceed the tolerable soil loss limit 1,4 g . m−2, were determined on March 18th and 28th, 2008. Big difficulties come with the assessment of the erodibility of heavy clay soils in the areas, where soil erosion ve­ri­fia­bly exists, but it is not assessable by objective calculating methods. Evident necessity of new know­ledge concerning the determination of wind erosion intensity follows from the results

Aplikace scénářů změny klimatu na meteorologické prvky ovlivňující větrnou erozi

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Using of wind erosion equation in GIS

The vulnerability of soil by wind erosion using the wind erosion equation (WEQ) in geographic information systems (GIS) was demonstrated on the cadastral area of Přísnotice, southeast of the Czech Republic. Raster layers were created for input factors of WEQ and potential soil loss by wind was calculated using the Raster Calculator. Subsequently, map outputs showing the potential vulnerability of soil to wind erosion were made. In the first variant, where the protective effect of the barriers was not taken into account, the wind erosion intensity reached 47.6 t.ha-1.year-1. In the second variant, where the protective effect of the barrier was assumed, the loss of soil was lower, the maximum value was 4.7 t.ha-1.year-1. The soil loss limit was exceeded, even in a situation where a relatively high protective barrier effect has been proposed. The advantage of determining of wind erosion vulnerability using ArcGIS is that it is possible to identify particular parts of soil blocks from the map outputs, which are the most vulnerable. Similarly, it is possible to design a windbreak network and simulate its protective effect using ArcGIS

Promrzání půdy na stanicích Pohořelice, Vizovice a Bystřice nad Pernštejnem

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Soil deflation analyses from wind erosion events

There are various methods to assess soil erodibility for wind erosion. This paper focuses on aggregate analysis by a laser particle sizer ANALYSETTE 22 (FRITSCH GmbH), made to determine the size distribution of soil particles detached by wind (deflated particles). Ten soil samples, trapped along the same length of the erosion surface (150–155 m) but at different wind speeds, were analysed. The soil was sampled from a flat, smooth area without vegetation cover or soil crust, not affected by the impact of windbreaks or other barriers, from a depth of maximum 2.5 cm. Prior to analysis the samples were prepared according to the relevant specifications. An experiment was also conducted using a device that enables characterisation of the vertical movement of the deflated material. The trapped samples showed no differences in particle size and the proportions of size fractions at different hourly average wind speeds. It was observed that most of particles travelling in saltation mode (size 50–500 μm) – 58–70% – moved vertically up to 26 cm above the soil surface. At greater heights, particles moving in suspension mode (floating in the air; size < 100 μm) accounted for up to 90% of the samples. This result suggests that the boundary between the two modes of the vertical movement of deflated soil particles lies at about 25 cm above the soil surface

Long-Term Impact of Wind Erosion on the Particle Size Distribution of Soils in the Eastern Part of the European Union

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