Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, the scientific journal of the Mendel University in Brno, Czech Republic

Recently, increasing attention has been paid to the anthropogenic degradation of the riverbed and its relationship to the ecological status of the adjacent river landscape. The key objective of this research was to determine the extent of the disturbance of the selected small streams and their riparian zone in a study area located in a forest and forest-agricultural landscape in the Czech Republic. The next step was to analyze the mutual relationships between the ecological status of the riparian vegetation and the hydromorphological status of the riverbed. The main working hypothesis considered the good hydromorphological status of the river as reflected in the favorable environmental status of the surrounding riparian habitats and vice versa. It was found in more than 90% of the total length of studied watercourses that the character of linkages between channel morphology and the ecological status of riparian vegetation is directly influenced by anthropogenic activities. An interesting finding is that the degraded streams in lowland sites are often encompassed by natural or close-to-natural habitats. On the contrary, the natural status of the riverbed was found in a significantly forested headwater area, but the riparian habitats did not reach even a close-to-natural status. This paper contributes to clarifying the significance of human impact on the river morphology, reflected in the reduction of connectivity between the terrestrial and fluvial parts of the river landscape. It helps to explore the most important disturbances affecting mutual interactions between the river and the riparian habitats.

Title: Závlahové stavby – opomíjená součást kulturního dědictví (Irrigation Facilities – a Neglected Part of Cultural Heritage) pdf Irrigation facilities represent one of the …

In sloped and intensively managed land, the soil characteristics are influenced mainly by water erosion intensity. In the present study, we evaluate the characteristics of Chernozems damaged by long-acting water erosion, particularly their retention and infiltration properties and possible impacts on soil fertility. Using infiltration experiments and a collection of intact samples, we performed analyses of the physical soil properties in individual transects. Our results confirm the lower infiltration capacity of deteriorated soil in the accumulation slope parts, which corresponded with the analyses of soil samples. The reduced bulk density in the accumulation slope parts exceeded 1.5 g·cm⁻³, indicating unsatisfactory (non-structured) soil conditions. In the transportation and eluvial slope zones, porosity values reached satisfactory numbers only at a depth of 10 cm. The median values of aeration showed a similar trend, but we recorded a higher value fluctuation.

The continuous rain simulator used with very precise dosing enables both simulation of characteristic rainfall as well as accurate determination of infiltration rate and automatic calculation of hydraulic conductivity of soils under natural conditions. As a part of the research of infiltration processes induced by characteristic rainfalls, the effects of stormy rainfalls were verified in the described project stage. Stormy rain with constant intensity was applied by rain simulator in a single ring infiltrometer. Samples were tested in the laboratory (soils and kaolinite) and directly in the field. During rain infiltration was measured ponding time. Theoretical base of the research comes from non-steady state unsuturated vertical infiltration, which process (in one-dimensional flow conditions) can be described by Richard´s equation. Final simplified solution is provided by Philip´s simplified infiltration equtions. Hydraulic conductivity K was approximated from the analysis of time series of the process of vertical non-steady cumulative infiltration, going after ponding time. Sorptivity S was calculated by the numerical experiment with known values of stormy rain intensity, ponding time and hydraulic conductivity. Compared to traditional methods (single or double ring infiltrometer), soil hydro-physical characteristic (K, S) determined by this method is more reliable, informative and verified by ponding time.

Since the 19th century, the irrigation industry on the territory of the Czech Republic has undergone considerable technological development and an increase in irrigated areas. Irrigation has become an important part of the Czech landscape. Large complex irrigation systems of tens to hundreds of...