The study on water erosion in the catchment basin of the Jeleni Brook was carried out in the years 1995–1999. The catchment of the Jeleni Brook has complex relief, receives frequent pre-cipitations and thus is more threatened by water erosion. Soil cultivation and water from quickly melting snow can also be the factors affecting soil erosion. Waters from the melting snow produce rills of the following dimensions (mean values): width from 11.5 to 13.6 cm, depth – from 6.4 to 7.1 cm and length – from 39 to 112 m. The mean values of soil losses vary from 0.5 to 2.02 t·ha–1.
Erosion caused by intensive storm precipitation occurs less frequently but makes much higher soil losses. One of the registered incidents shows that 51.6 t·ha–1 (4.5 mm of soil layer) can be washed out from the area of 0.66 ha. Combined effect of outwashing and ploughing in lower parts of slopes created new forms of relief such as agricultural terraces (escarps). Agricultural terraces assume the shape of scarps up to 2 m high and of different length (e.g. 150 m) along with the land use border-lines between e.g. forest and field or field and grassland.
Agriculturally used soils within this catchment need protection based mainly on agrotechnical measures or on alteration of land use. Some areas should be afforested.
The paper presents the results of the pitting resistance investigations of selected stainless steels in the chloride environment and the simultaneous impact of erosive factors using the cyclic polarization technique. Additionally, using electrochemical techniques, ie: electrochemical impedance spectroscopy (EIS) and measurement of corrosion potential, the behavior of the passive layer of selected stainless steels in the environment of chlorides and erosion was examined. On the basis of the obtained results, the resistance of stainless steels 1.4301 and 1.4404 was found, both on the effect of chloride ions and erosive factors in the studied systems. Both tested steels are susceptible to pitting corrosion. It was found that a good measure of erosive impact on stainless steel is both impedance spectrum analysis and continuous monitoring of the corrosion potential of steel.
Water reaches a river in the form of surface runoff (precipitation that has not seeped into the ground) or underground outflow (groundwater). Both of these factors affect the erosion and river deposition processes that shape the river valley. Understanding them is crucial for effective river management.
The article presents research on solid particle erosive wear resistance of ductile cast iron after laser surface melting. This surface treatment technology enables improvement of wear resistance of ductile cast iron surface. For the test ductile cast iron EN GJS-350-22 surface was processed by high power diode laser HPDL Rofin Sinar DL020. For the research single pass and multi pass laser melted surface layers were made. The macrostructure and microstructure of multi pass surface layers were analysed. The Vickers microhardness tests were proceeded for single pass and multi pass surface layers. The solid particle erosive test according to standard ASTM G76 – 04 with 30°, 60° and 90° impact angle was made for each multi pass surface layer. As a reference material in erosive test, base material EN GJS-350-22 was used. After the erosive test, worn surfaces observations were carried out on the Scanning Electron Microscope. Laser surface melting process of tested ductile cast iron resulted in maximum 3.7 times hardness increase caused by microstructure change. This caused the increase of erosive resistance in comparison to the base material.
The present study tries to quantify soil losses using Geographic Information Systems (GIS) and analytic hierarchy pro-cess (AHP) in the Medjerda watershed (Algerian-Tunisian border). The Analytic Hierarchy Process (AHP) method is used in the quantification of erosion qualitative characteristics, through its weighting. It is used for many problems requiring decision-making. This catchment area is characterized by moderately consistent lithology, irregular rainfall, medium slope and low vegetation cover, which makes it very sensitive to erosion. Therefore we claim to develop a spatialization map of vulnerable areas, based on analytic hierarchy process and GIS that define the combination of specific factors. The integration of the thematic maps of the various factors makes it possible to identify the impact of each factor in the erosion, to classify the sensitive zones, and to quantify the soil losses in the basin. This mapping will be an important tool for land use planning and risk management. From the distribution map of erosive hazards, we have identified four classes of vulnerabil-ity, areas with very high to high vulnerability are mainly in the northern part of the watershed (where the relief is very important).
The paper reports experimental results of the analysis of the 145Cr6 steel surface after erosion using the profilometrical technique by means of interferometry streaks. Erosive tests were carried out using abrasive containing quartz sand used in water jet cutting. Differences in the intensity of erosive wear were dependent on the angle of the abrasive stream (10◦ ; 15◦ ; 20◦ ; 30◦ ; 60◦ ; 90◦). In order to determine the characteristic features of the surface layer after the impact of the erosive stream, its characteristic parameters, such as roughness Ra and Sa for linear and field measurements, were analysed. Geometrical features of the regions investigated, such as shape, depth, angle of the abrasive stream, are presented. The analysis was carried out in two-dimensional (2D) and three-dimensional (3D) coordinate systems.
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