The paper presents basic facts and knowledge of special survey focused on detection and evaluation methods of subsurface drainage systems by means of remote sensing. It is aimed at the complex analysis of applied processes in spatial localization, classifi cation or assessment of subsurface drainage systems' actual condition by means of distance research methods. Data collection, their analysis and interpretation have been shown in seven experimental areas in the Czech Republic. Mainly it means determination of potential, application principles and limits of pracical use of diff erent technologies and image data obtained by remote sensing in solving questions.
This study focused on the hydraulic efficiency of vertical earthworm channels (henceforth referred to as macropores or channels). The parameters selected for investigation were the rate of change in hydraulic soil conductivity in the channel walls due to compaction, the rate of this compaction, and the wall stability against running and stagnant water. We preferentially tested the variants for infiltration of water flowing from the soil horizons against gravity (e.g. from the level of installation of tile and controlled drainage). The details of influx and infiltration processes were examined both in the field and more thoroughly in the laboratory using an accurate continuous infiltrometer constructed at the Research Institute for Soil and Water Conservation (RISWC), Czech Republic. Both direct measurements and indirect evidence consisted of tests of individual natural macropores directly in the field, as well as tests of intact collected samples and artificial samples with variants of natural, artificially extruded, and cut out tubular macropores. We studied the processes occurring in macropores with diameters of ca. 5 mm and larger. In these particular conditions, we identified the apparent saturated hydraulic conductivity (K s ') of the soil horizons (including macropore-mediated vertical surface infiltration and preferential flow to soil followed by radial infiltration) most frequent as K i (apparent saturated hydraulic conductivity affected by preferential flow or influx of water) from 50 to 200 cm/h. In some cases, saturated hydraulic conductivity of earthworm channel walls (K sw ) was reduced in the order of tens of percent compared with matrix K s . The increase of bulk density of soil (ρ d ) in the macropore vicinity reached the maximum of 25%. The intensity of macropore wall erosion (i er ) ranged from 0 to 70 mg/min/dm 2 .
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.
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