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1

Revised holostratigraphy of the Tithonian-Berriasian transition at Tré Maroua (Le Saix, Hautes-Alpes, SE France): study of a rejected Berriasian GSSP candidate

Granier Bruno R.C., Benzaggagh Mohamed, Ferry Serge

Volumina Jurassica

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2023

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Vol. 21

1--18

EN

The study of the Tithonian and lower Berriasian succession of Le Saix (Hautes-Alpes, France) has made it possible to better characterize the lithological succession at a former Berriasian GSSP candidate, its set of microfacies, the stratigraphic ranges of the main groups of marine plankton and therefore the calpionellid and saccocomid biozonations. On the lithological level, the Tithonian strata are characterized by thick-bedded breccias representing debris flows and related calciturbidites, whereas the Berriasian strata are typically white limestones. The lower part of the Berriasian is comprised of scattered intercalations of thin-bedded breccias and calciturbitides (including cryptic mud calciturbidites). In thin sections, the white limestones display mud- to wackestone textures and their allochems are mostly tiny bioclasts (e.g., radiolarians, calpionellids, saccocomids). Calciturbidites have wacke- to grainstone textures and their allochems are mostly pseudointraclasts and extraclasts, comprising various bioclasts and some ooids. Mud turbidites are made of micrograin-stones some yielding almost exclusively well-sorted calpionellids, which were previously erroneously interpreted as the signature of “explosions” or “blooms” of Calpionella alpina. Breccias are mostly lithoclastic floatstones with a matrix similar to that of the calciturbid- ites. Their lithoclasts are either extraclasts sensu stricto, i.e., material derived from updip shallow-water areas, or pseudointraclasts representing reworked subautochthonous material, i.e., mud- and wackestone lithoclasts with radiolarians, saccocomids and/or calpionellids. Radiolarians are common over the whole studied interval. Saccocomids are part of the dominating biota reported from the lower and lower upper Tithonian interval whereas calpionellids replace them in the uppermost Tithonian to lower Berriasian interval. Minor plank- tonic groups comprise calcareous dinoflagellates and Globochaete alpina; Iranopsis nov. group is also present. Intervals with saccocomid sections characteristic of zones 4-5 and zone 6 are respectively ascribed here to the lower Tithonian (4-5) and the lower upper Tithonian (6). The biozonation of the calpionellid group sensu lato allows identification of i) the Boneti Subzone of the chitinoidellids, ii) the Cras- sicollaria Zone, more specifically its Tintinnopsella-Intermedia (A1), Intermedia-Alpina (A2) and Brevis-Massutiniana (A3) subzones, and iii) the Alpina Zone, with its Alpina-Parvula (B1) and its Alpina-Remaniella (B2) subzones. On the basis of biostratigraphical and sedimentological data, most zonal boundaries prove to be hiatal, located at the erosional base of breccia or turbidite layers whereas the Tithonian/Berriasian stage boundary appears to be located at a strike-slip fault plane in the Tré Maroua section.

2

Quantification of solid particle transport in suspension in a stream : Case of Wadi Zeddine Ain-Defla, Algeria

Bouleknafet Zohir, Elahcene Omar

Journal of Water and Land Development

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2023

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no. 56

102--108

EN

Arid and semi-arid areas are characterised by differentiation in meteorological conditions. Sometimes the rains are rare and not very intense and at other times they are dense and very intense, resulting in torrents that often lead to strong soil erosion. Most of the time, the losses occur at the solids level because the erosion effect is too high. In this study, we want to evaluate the transfer of solid sediments as a function of liquid transport in the basin of Wadi Zeddine at Ain Defla in Algeria. To understand this phenomenon, we used the data of liquid flows (Ql, m3∙s-1) and concentration of suspended sediments (C, g∙dm-3), transported in the river, the data collected by the NWRA (National Water Resources Agency), over 24 years have been used to find a relationship between these two quantities, to estimate the quantity of solid transport Qs (kg∙s-1) in the watercourse of the catchment area studied. The results obtained show a good correlation between solid and liquid flows, with a correlation coefficient estimated at 90%, and the average annual sediment supply recorded at the outlet of the Wadi Zeddine watershed is estimated at around 88,048 Mg, which corresponds to 202 Mg∙km-2∙y-1 erosion rate. This value is comparable to those found in other regions with similar hydrological regimes.

3

Badania numeryczne wpływu erozji oraz zabrudzeń łopaty na pracę turbiny wiatrowej

Malecha Ziemowit, Sierpowski Korneliusz

Instal

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2023

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nr 7/8

7--13

PL

W pracy przeprowadzono badania numeryczne wpływu zabrudzeń, oblodzenia oraz uszkodzeń łopat turbiny wiatrowej na produkcję mocy. Przeanalizowano dwa scenariusze kontroli pracy turbiny wiatrowej, standardową oraz zaawansowaną. Kształt oblodzonych oraz uszkodzonych profili opracowano bazując na wynikach eksperymentalnych oraz obserwacjach rzeczywistych łopat turbin. Pokazano, że w przypadku turbiny oblodzonej, zabrudzonej oraz zerodowanej produkcja mocy może spaść odpowiednio o około 50%, 16% oraz 12.5%. Przeanalizowano wpływ spadku produkcji przez turbinę na współczynnik wykorzystania mocy. Na przykładzie lokalizacji na Morzu Bałtyckim, pokazano, że współczynnik wykorzystania mocy może spaść o 0.023% oraz dodatkowo o około 0.005% wraz ze zwiększeniem udziału dni z zabrudzonymi łopatami w roku o kolejne 10%.

EN

Numerical studies of the impact of dirt, icing and eroded of wind turbine blades on power production were carried out. Two scenarios of wind turbine operation control, standard and advanced, were analyzed. The shape of ice-covered and eroded profiles was developed based on experimental results and observations of real turbine blades. It has been shown that in the case of an ice-covered, dirty and eroded turbine blade, power production can decrease by approximately 50%, 16% and 12.5%, respectively. The influence of the decrease in power production on the capacity factor was analyzed. Using the example of a location in the Baltic Sea, it has been shown that the capacity factor can decrease by 0.023% and additionally by about 0.005% with an increase in the share of days with dirty blades in the year by another 10%.

4

Rainfall Erosivity Factor within the Volyn Region

Matviichuk Bogdan, Romantschuk Ludmila, Matviichuk Nataliia

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 6

135--146

EN

The article presents results of the research and mathematical modelling of the rainfall erosivity factors. Erosion, whether water, wind or resulting from soil cultivation, includes three processes – soil descaling, movement and sedimentation. Spatial characteristics of precipitation during two researched periods are similar, having certain quantitative peculiar features. A common feature is maximum precipitation in the southwest and to a lesser extent in the eastern part of the region. Minimum precipitation is typical for the western part of the region. Peculiar feature of the second period of research is increase of contrasting effect of precipitation regime, when minimum values of precipitation decrease and maximum ones increase. Enhancement of contrasting effect of precipitation in space or time may cause increased intensity of erosion processes to the extent where the intensity of precipitation increases due to such contrasting effect. Thus, doubtless interest lies in the research of greater spatial or time contrasting effect of precipitation regime to activate water erosion. Thus, spatial peculiarities of distribution of precipitation within territory under study and time patterns correlate, but have their own special features. Clearly, total amount of precipitation as well as time distribution as a marker of correlation of intensification factor of erosion processes and defence mechanisms of vegetative cover are dominant for total losses of soil due to erosion. Coincidence of time of intense precipitation in summer and availability of vegetative cover reduces erosion. Nevertheless, continuance of intense precipitation when harvesting is started may cause intensification of water erosion of soil. Use of spatial variables and regression equations for spatial data calibration helped to estimate the spatial variation of precipitation on the territory under study. Comparison of two periods of research showed that in 2010–2016 significant reduction of rainfall erosivity factor has taken place in comparison with the previous period 9.6–65.4 MJ mm ha–1 h–1 per year. In Turiyskyi and Kovelskyi district changes in rainfall erosivity factor were minimal (9.6 and 16.7 MJ mm ha–1 h–1 per year respectively). Conversely, in Ivanytskyi and Gorokhivskyi districts changes were the most significant – 58.1 and 65.4 MJ mm ha–1 h–1 per year respectively.

5

Modeling Soil Erosion Using RUSLE and GIS – A Case Study of Korifla Sub-Watershed (Central Morocco)

Eddefli Fatimazahra, Ouakil Abdelhadi, Khaddari Achraf, Tayebi Mohamed

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 4

128--137

EN

Soil loss is a problem that contributes to land degradation in many countries and Morocco is no exception. Our study focuses on water erosion in Korifla, a sub-basin of the Bouregreg watershed in northern Morocco. The objective is to quantify erosion using the RUSLE method which is based on five factors: Runoff erosivity, soil erodibility, cover factor, topography and conservation practices. These are processed by remote sensing and a geographic information system. The soil loss map shows that on an area of 1838 km2, erosion is estimated to be between 0.00 t/ha/year and 27.61 t/ha/year. The cumulative effect of the factors R, K, LS, C, and P are both the origin of this erosion and its spatial distribution.

6

Integration of Sentinel2 Data into a GIS System for the Mapping of Areas at Risk of Degradation by Applying the MEDALUS Model – Case of Sidi Mohamed Ben Abdellah Watershed (Morocco)

Ouakil Abdelhadi, Eddefli Fatimazahra, Ben Hichou Badr, Chao Jamal, Elbelrhiti Hicham

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 7

216--228

EN

Located in the central northwest of Morocco, the Sidi Mohamed Ben Abdellah dam watershed is particularly exposed to soil degradation risk due to a combination of factors such as wide exposure, lithological heterogeneity, and varying climatic conditions. Therefore, the purpose of the conducted study was to create a spatial map of the areas most susceptible to degradation using the MEDALUS (Method for the Evaluation of the Degree of Soil Loss Susceptibility) model to pinpoint the areas that are most vulnerable to the risk of erosion. The MEDALUS model is a commonly used tool for assessing soil degradation and erosion risks. It takes into account physical, climatic, and land use factors to determine the susceptibility of an area to soil loss. To apply the model to the Sidi Mohamed Ben Abdellah dam watershed, the data on factors such as slope, soil type, vegetation cover, and precipitation would be collected, and this information would be used to generate a map of the areas at greatest risk of erosion. This map could then be used to prioritize conservation and management efforts in the watershed and identify the areas that require additional protection or restoration. The map of erosion sensitivity is produced by combining factors that contribute to the phenomenon, such as vegetation cover, climate, relief, pedology, and human intervention. Cross-referencing these factors in a GIS (geographic information system) allows generating an erosion sensitivity map that highlights the most vulnerable areas to this hazard in the region.

7

Analiza wpływu parametrów napawania laserowego LMD na wybrane właściwości napoin wytworzonych z proszku HS6-5-2c na stali 1.4923

Chrzanowski Wojciech, Napadłek Wojciech, Bogdanowicz Zdzisław

Biuletyn Wojskowej Akademii Technicznej

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2023

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Vol. 72, nr 1

116--130

PL

W pracy zaprezentowano wyniki badań napoin wytworzonych technologią napawania laserowego LMd (Laser Metal Deposition) z zastosowaniem różnych parametrów wiązki laserowej. na powierzchni podłoży ze stali 1.4923 w kształcie prostopadłościanów wytworzono napoiny wielościegowe z proszków hs6-5-2c o różnym stopniu przykrycia. W ramach prób napawania laserowego wytworzono próbki, na których następnie przeprowadzono badania topografii powierzchni, obserwacje mikrostruktury oraz pomiary twardości w poszczególnych strefach warstwy wierzchniej podłoża, to jest w strefie napoiny, strefie wpływu ciepła (sWc) oraz w strefie materiału rodzimego. obserwacjęi analizę powierzchni napoin oraz mikrostruktury w przekroju poprzecznym próbek po napawaniu LMd zrealizowano z zastosowaniem mikroskopii optycznej ze światłowodową transmisją obrazu. pomiary twardości wykonano, używając twardościomierza Vickersa FLc-50a. na podstawie obserwacji mikroskopowych stwierdzono, że uzyskane napoiny mają regularny i powtarzalny kształt. Ponadto na powierzchniach wytworzonych napoin oraz w strefie wtopienia materiału napoiny z materiałem podłoża nie zauważono występowania wad procesowych. Twardość uzyskanych napoin wynosiła 500-700 hV0,1. Wytworzone na bazie proszku hs6-5-2c napoiny poddano badaniom odporności na erozję, które wykazały znacznie wyższą odporność na zużycie erozyjne (nawet ok. pięciokrotnie) w porównaniu z materiałem podłoża (stal 1.4923) bez napawania.

EN

This paper presents the results of testing surfacings produced by LMd (Laser Metal deposition) laser deposition technology for different laser beam parameters. on the surface layer of rectangular-shaped samples, made of 1.4923 steel, multiwall surfacing was produced from hs6-5-2c powder with different degrees of coverage. as a part of the laser deposition verification and testing, surface topography, microstructure and hardness tests were carried out in the deposition zone, heat affected zone, and the zone of the parent material. The surface of the surfacing and the microstructure in cross-section were observed on an optical microscope with fibre-optic image transmission. Hardness measurements were made in the cross-section of the sample using a Vickers FLc-50a hardness tester. Based on the observations, it was found that the obtained surfacings have a regular and repeatable shape. There were no welding defects on the surfaces of the produced surfacings and in the zone of fusion of the surfacing material with the substrate material. The hardness of the surfacings was obtained in the range of 500-700 hV0.1. The surfacings produced by LMd technology were subjected to erosion resistance tests, which showed significantly higher (about 5 times higher) resistance to erosion wear of the produced surface layers (surfacings based on hs6-5-2c powder) in comparison with the substrate material, i.e., steel 1.4923.

8

Analiza procesów uszkodzeń łopat turbin parowych

Chrzanowski Wojciech, Napadłek Wojciech, Bogdanowicz Zdzisław

Biuletyn Wojskowej Akademii Technicznej

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2023

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Vol. 72, nr 2

39--63

PL

Artykuł dotyczy przeglądu literatury oraz określenia i analizy przyczyn zużycia łopat turbin parowych. W wyniku analizy stwierdzono, że głównymi przyczynami uszkodzenia łopat są procesy erozyjno-korozyjne oraz wpływ podwyższonej temperatury wewnątrz turbiny, powodujące m.in. efekt wydłużenia i odkształcenia łopat oraz występowanie pęknięć w wyniku gwałtownych zmian temperatury. Przegląd literatury i analiza zjawisk zniszczenia wykazały, że łopaty narażone są na erozję wynikającą z warunków ich pracy, w tym oddziaływania środowiska pary wodnej i/lub wtrysku kondensatu chłodzącego w strefie ostatniego stopnia części niskoprężnej turbiny. Zjawisko erozji występuje głównie na krawędziach wlotowych i wylotowych łopat, powodując oprócz zmniejszenia sprawności turbiny także efekt nierównomiernego wyważenia elementów współpracujących (różne zużycie łopat w jednym stopniu wirnika). erozja może także powodować wzrost naprężeń mogący doprowadzić do poważnych uszkodzeń nie tylko łopatek, lecz także podzespołów turbiny. Łopaty turbin parowych są narażone również na oddziaływanie agresywnych związków chemicznych (chlorki, siarczany oraz krzemiany metali alkalicznych pochodzące z pary wodnej), w wyniku których na łopatach może zachodzić korozja równomierna, a także wżerowa. Dlatego w artykule przeanalizowano wpływ warunków pracy na występujące uszkodzenia oraz możliwości związane z prognozowaniem trwałości eksploatacyjnej łopat.

EN

The article is a review of the literature data related to the wear of steam turbine blades. The literature review have found that the main causes of blade damage are erosion, corrosion, and the occurrence of elevated temperatures inside the turbine, which cause, among other things, blade elongation, deformation, and cracks due to rapid temperature changes (thermal shock). A review of the literature has shown that blades are a subject to erosion resulting from operating conditions in which the blades strike water droplets formed from steam or from the injection of cooling condensate in the zone of the last stage of the low-pressure part of the turbine. erosion occurs mainly at the inlet and outlet edges of the blades, causing imbalance (different blade wear in one rotor stage) in addition to reducing turbine efficiency. erosion can also cause an increase in stresses that can lead to serious damage not only to the blades, but also to other turbine components. Steam turbine blades are also exposed to aggressive working environment (chlorides, sulfates, and alkali metal silicates from steam) as a result of which uniform and also pitting corrosion can occur on the blades. The article also analyses the effect of operating conditions on the damage that occurs, as well as the literature on predicting turbine blade life.

9

Phenomenological model of cavitation erosion of nitrogen ion implanted HIPed Stellite 6

Szala Mirosław

Advances in Materials Science

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2023

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Vol. 23, nr 1(75)

98--109

EN

Stellites are a group of Co-Cr-C-W/Mo-containing alloys showing outstanding behavior under cavitation erosion (CE) operational conditions. The process of ion implantation can improve the CE resistance of metal alloys. This work presents the elaborated original phenomenological model of CE of nitrogen ion implanted HIP-consolidated (Hot Isostatically Pressed) cobalt alloy grade Stellite 6. The ultrasonic vibratory test rig was used for CE testing. The nitrogen ion implantation with 120 keV and fluence of 5 × 1016 N+/cm−2 improves HIPed Stellite 6 cavitation erosion resistance two times. Ion-implanted HIPed Stellite 6 has more than ten times higher CE resistance than the reference AISI 304 stainless steel sample. Comparative analysis of AFM, SEM and XRD results done at different test intervals reveals the kinetic of CE process. The model includes the surface roughness development and clarifies the meaning of cobalt-based matrix phase transformations under the nitrogen ion implantation and cavitation loads. Ion implantation modifies the cavitation erosion mechanisms of HIPed Stellite 6. The CE of unimplanted alloy starts on material loss initiated at the carbides/matrix interfaces. Deterioration starts with cobalt matrix plastic deformation, weakening the carbides restraint in the metallic matrix. Then, the cobalt-based matrix and further hard carbides are removed. Finally, a deformed cobalt matrix undergoes cracking, accelerating material removal and formation of pits and craters' growth. The nitrogen ion implantation facilitates ɛ (hcp—hexagonal close-packed)) → γ (fcc—face-centered cubic) phase transformation, which further is reversed due to cavitation loads, i.e., CE induces the γ → ɛ martensitic phase transformation of the cobalt-based matrix. This phenomenon successfully limits carbide removal by consuming the cavitation loads for martensitic transformation at the initial stages of erosion. The CE incubation stage for ion implanted HIPed Stellite 6 lasts longer than for unimplanted due to the higher initial content of γ phase. Moreover, this phase slows the erosion rate by restraining carbides in cobalt-based matrix, facilitating strain-induced martensitic transformation and preventing the surface from severe material loss.

10

Rola scaleń gruntów w zmniejszaniu zagrożenia erozyjnego

Bożek Piotr, Doroż Arkadiusz, Taszakowski Jarosław

Przegląd Geodezyjny

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2022

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R. 94, nr 11

18--21

PL

Co roku niemal na całym świecie erozja przyczynia się do degradacji gleby, pogorszenia warunków do prowadzenia działalności rolniczej oraz zmiany krajobrazu rolniczego. Straty dla gospodarki światowej wiążą się z kosztami utraconych plonów oraz z kosztami związanymi z rekultywacją zdegradowanych terenów. Proces zapobiegania oraz niwelowania skutków związanych z zagrożeniem erozyjnym jest procesem czasochłonnym, wymagającym dużych nakładów pracy. Redukcja zagrożenia erozyjnego związana jest ze zmianą struktury przestrzennej dla obszarów użytkowanych głównie rolniczo. Scalenie gruntów wpisujące się w kształtowanie obszarów wiejskich jest jednym z najskuteczniejszych narzędzi pozwalającym na zmniejszenie zagrożenia erozyjnego. Do najpopularniejszych narzędzi identyfikujących zagrożenie erozyjne, które może zostać zredukowane w ramach scaleń gruntów zaliczany jest model RUSLE (Revised Universal Soil Loss Equation). Pozwala on na określenie liczby materiału glebowego, który ulega degradacji. Wykorzystuje on dane wysokościowe, dane o użytkowaniu, aby skutecznie wyznaczyć obszary zagrożone.

EN

Every year, almost all over the world, erosion contributes to soil degradation, deterioration of agricultural conditions and changes in the agricultural landscape. The losses to the world economy are related to the costs of lost crops and the costs of rehabilitating degraded land. The process of preventing and reducing the effects of erosion risk is a time-consuming and labor-intensive process. The reduction of the erosion risk is related to the change in the spatial structure of areas used mainly for agriculture. Land consolidation, which is part of the shaping of rural areas, is one of the most effective tools to reduce the risk of erosion. The RUSLE model (Revised Universal Soil Loss Equation) is one of the most popular tools for identifying erosion risk that can be reduced as part of land consolidation. It allows you to determine the number of soil materials that are being degraded. It uses elevation data and usage data to effectively designate risk area.

11

Warunki występowania erozji w obszarze stacji narciarskich w Karpatach Polskich

Piątek Dawid, Krzemień Kazimierz, Gołąb Agata

Landform Analysis

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2022

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Vol. 41

17--31

PL

Wzrost popularności turystyki narciarskiej wpływa na intensywny rozwój stacji narciarskich, w szczególności tych posiadających koleje linowe. W literaturze szeroko opisywane są przyrodnicze skutki narciarstwa, również wpływ na rzeźbę terenu. Jednakże, nie ma opracowań wskazujących stacje narciarskie jako obszary o zwiększonej podatności na erozję oraz skalę przestrzenną tego zjawiska. Celem badań było poznanie warunków wystąpienia erozji oraz intensywnego przeobrażania stoków w strefie stacji narciarskich na przykładzie Karpat Polskich. W tym celu, z wykorzystaniem danych GUGiK, oprogramowania GIS oraz metod statystycznych przeprowadzono analizę liczby, położenia i morfologii stoków narciarskich oraz sposobów ich utrzymania. Dokonano również podziału stacji narciarskich ze względu na typy rzeźby w ich otoczeniu oraz dominujące procesy morfogenetyczne. Uzyskane parametry morfometryczne oraz dane o infrastrukturze stacji narciarskich wykorzystano w analizie składowych głównych (PCA), która pozwoliła na wytypowanie stacji narciarskich o największej podatności na erozję w Karpatach Polskich. Otrzymane wyniki wskazują, że stacje narciarskie w masywie Skrzycznego charakteryzują się największym zagrożeniem wystąpienia erozji. Zwrócono również uwagę na duży potencjał erozyjny stacji na Kasprowym Wierchu oraz stacji w najwyższych partiach Beskidów. Wykazano, że najmniejszy potencjał erozyjny cechuje nisko położone, niewielkie stacje narciarskie. Badania wskazują również na istotną rolę sztucznego naśnieżania oraz występowania nieciągłej pokrywy roślinnej na warunki wystąpienia erozji w obszarze nartostrad niezależnie od energii rzeźby.

EN

Increasing in popularity of skiing lead to intensive development of ski resorts, especially these with cable transport. In the literature is a wide characteristic of environmental effects of skiing as well as the impact on the relief. However, there is a lack of works presenting ski resorts as areas with higher susceptibility to erosion and the spatial scale of the phenomenon. For this purpose, with the use of Head Office of Geodesy and Cartography (GUGiK) data, GIS software and statistical methods, an analysis of the number, location and morphology of ski slopes and the methods of their maintaining was carried out. The ski resorts were also divided according to the types of relief in their surroundings and the dominant morphogenetic processes. The obtained morphometric parameters and data about the infrastructure of ski resorts were used in the principal component analysis (PCA) allowed to select ski resorts with the highest susceptibility to erosion in the Polish Carpathians. The obtained results indicate that the ski stations in the Skrzyczne massif are characterized by the highest risk of erosion. Attention was also paid to the high erosion potential of the station on Kasprowy Wierch and the stations in the highest parts of the Beskids. It has been shown that the lowest erosion potential is found low mountains, small ski resorts. The research also indicates a significant role of artificial snowmaking and the presence of discontinuous vegetation cover on the conditions of erosion in the area of ski slopes, regardless of the relief energy.

12

The eco-hydraulics base as flood mitigation to overcome erosion and sedimentation problems : a case study in the Lae Kombih River, Indonesia

Ziana Ziana, Azmeri Azmeri, Yulianur Alfiansyah, Meilianda Ella

Journal of Water and Land Development

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2022

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no. 55

229--239

EN

Erosion and sedimentation have a very big influence on flooding. Floods are strongly influenced by land use and population activities that change the river’s physical condition, including erosion and sedimentation. The river upstream was very steep, and the downstream was narrowing and meandering with high rainfall recorded. This study analyses erosion, sedimentation, and its handling using the eco-hydraulic base. The method involves input rainfall data, river hydraulics, land use, watershed area, and land cover. The analysis of hydrology, hydraulics, land use, flood discharge, and eco-hydraulic, inundation height, vegetation diameter, velocity reduced, and riverbank width measured in five bridges cross-sections along the river. The eco-hydraulic compares the width of existing riverbanks and design, high inundation, and the vegetation diameter to minimise flood discharge. Erosion in the right cliff is 22.73% and the left cliff is 37.04%, land erosion was 225.83 Mg∙ha-1∙year -1. The river’s bottom is formed by rocks of 0.18-1.30 mm. The plantation land used around the Lae Kombih River grows mainly an oil palm with a diameter of 0.5-0.7 m. The riverbank design on 100 m for vegetation diameter of 0.1-1.0 m can retain flood discharge for five years return period up to 72.3%, resulting in discharge of 112.04209.43 m3∙s-1. The largest erosion and sedimentation on the river border is Dusun Silak, so it is recommended to plant Vetiveria zizanioides, Ipomoea carnea and Bambusoideae. An inundation height of 0.9 m can be recommended to design an embankment to be used as flood mitigation.

13

Erosional Damages on Concave Banks of Directional Arcs in Natural Torrent Bed

Jakubis Matúš, Jakubisová Mariana

Journal of Ecological Engineering

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2022

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Vol. 23, nr 9

44--52

EN

The article deals with the research of erosive damages of concave (outer) sides in directional circular arcs in the natural torrent bed. The research was carried out on 22 reference circular arcs on the Hučava torrent in the geomorphological unit of Poľana (Central Slovakia). The relation between R/Wbkf ratio (radius of curvature R/torrent bed width inside the banks Wbkf) and the bank slope angle BA of the concave arc BA = f(R/Wbkf) was analyzed. The relationship between R/Wbkf ratio and the percentage of vegetation cover VEG on the concave bank of the directional arc VEG = f(R/Wbkf) was analyzed as well. At the same time, the relation between ratio R/Wbkf and the VEG/BA coefficient was studied, which simultaneously the influence of vegetation cover and bank slope in connection with its erosive damage VEG/BA = f(R/Wbkf). It was found that the determination index for the relation BA=f(R/Wbkf) has the value of R2 = 0.924, for the relation VEG = f(R/Wbkf) the value of R2 = 0.953 and for the relation VEG/BA = f(R/Wbkf) the value of R2 = 0.967.

14

Coupling of Space Remote Sensing and GIS for Detection of Areas at Risk of Degradation (Sidi Mohammed Ben Abdellah Dam Case – Morocco)

Abdelhadi Ouakil, Badr Benhichou, Kaoutar Elbelrhiti, Taha Amimi, Jamal Chao, Hicham Elbelrhiti

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 6

161--172

EN

Sidi Mohamed Ben Abdellah dam watershed is one of the most vulnerable areas of the risk of soil degradation due to its wide exposure, lithological heterogeneity and varying climatic factors. In this sense, the qualitative study of the spatial-temporal evaluation of ground-level occupancy from satellite visualisation data (acquired by the Landsat TM 5 and Landsat TM 8) device derives a land-use map that shows the areas at risk of degradation after the integration of a combination of multiple factors into a GIS geographic information system (climate, terrain, pedology, vegetation cover and human intervention (anti-erosive practice); The results require adaptive vision to better control the phenomenon, to reduce its severity in areas at high risk of soil degradation.

15

Solid particle erosion in the sudden contraction of raw water pipeline

Amori Karima E., Al-Salmany Zaid

Diagnostyka

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2022

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Vol. 23, No. 1

art. no. 2022110

EN

The steady 3-D raw water turbulent flow is numerically investigated. This flow is formed of solid silica sand (quartz) carried by water in stainless steel pipe. The flow in a straight pipe and flow in a pipe with a sudden contraction are analyzed using a two-way coupled Eulerian-Lagrangian approach. Erosion rate is estimated by Oka erosion model combined with the constant coefficient of restitution. The effect of solid particles mass flow rate, inlet velocity, particle diameter, internal pipe diameter, orientation, contraction coefficient, and wall pipe contraction angle on erosion rate are examined. The predicted erosion is distributed homogenously for straight pipe, while the step wall area of the contraction is the most eroded part. The erosion rate increases with the increase of solid particles diameter, flow rate, inlet velocity, and decreasing pipe diameter. Iit is found that the erosion is limited till the particle diameter reaches 500 µm then it starts to increase. The erosion rate increases with decreasing contraction coefficient and step wall angle. When the step wall angle decreased to 300, the erosion rate is reduced by 30 times that for 900. So, decreasing step wall angle can be considered as a geometrical solution to reduce erosion rate.

16

Properties of the aggressiveness of geothermal and marine water and their negative impact on hydromechanical fittings

Ciosmak Małgorzata

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2021

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nr 68 (140)

78--85

EN

This article concerns the issue of the long-term operation of hydromechanical fittings during their contact with aggressive water. The aim of this analysis was to investigate the significance of the quality of water during the operation of wind power farms and geothermal power stations, especially hydromechanical fittings during long-term operation at the base of the Baltic Sea and geothermal power stations. This article presents the properties of water and their impact on hydromechanical equipment during long-term operation in marine and geothermal waters. The paper includes the analysis and evaluation of their impact. Additionally, the article describes important problems with the operation of wind power farms and geothermal power stations. The results of periodical analyses of southern Baltic marine water and thermal groundwater from “Geotermia Podhalańska” were evaluated and used as the basis for future research. Every negative parameter of water, known as its aggressiveness, adversely affects the basic materials of wind masts and pipelines, as well as the hydromechanical equipment in contact with marine and thermal water. The presented results show the necessity of controlling the water quality prior to the operation of geothermal water and building wind power masts in coastal marine water. Attention was paid to corrosion during contact with aggressive water with unprotected materials. This issue is rarely seen in the literature but is very important.

17

Symulacja i predykcja erozji wybrzeża wybranych odcinków Zatoki Gdańskiej w modelu SWAN

Sapiega Patryk

Przegląd Geologiczny

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2021

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Vol. 69, nr 11

721--727

EN

The increasing climatic changes and their possible negative impact on the marine and coastal environment prompt the search for alternative estimating and predicting dangerous phenomena. Hydrodynamic modeling is an underappreciated model which enables forecasting waves and their effects. In the presented work, the author assessed the influence of the dynamics of undulations on the morphological changes of the Gulf of Gdańsk coast in three transects representing different geomorphological zones of the shore. Using the SWAN wave model, simulations were carried out reflecting the hydrodynamic conditions of the most giant storms in 2015-2020, calculating the amount of eroded sediment material in bottom and suspension transport. In addition, based on the significant wave height data from ERA5-ECMWFfrom 1981-2020 and the assumed scenarios, a prediction was made of a potential increase in coastal erosion caused by the rise in the mean value of the significant wave height. Taking into account the implemented and set atmospheric, hydrodynamic, and sedimentological conditions, it has been estimated that the highest erosion characterizes the cliff area in Gdynia-Orłowo (transect B), where the average amount of erosion of the bottom sediment is 0.5 kg/m/s, of the sediment in suspension - 20 kg/m/s, and the average speed of the transported sediment exceeds 2 m s-1. The lowest dynamics of changes is characteristic for the western part of the Vistula Spit (transect C), where the average velocity of the transported sediment is 0.28 m s-1, and the average size of the eroded bottom sediment is 0.014kg/m/sand 0.15kg in suspension/m/s. In the analyzed storm events, at all locations, the greatest erosion was generated by the wave conditions from January 2019. The maximum wave height in the open sea was record-breaking, over 13 meters. Depending on the analyzed area and its geomorphology and exposure to storm waves, the predicted amount of erosion varied significantly. For Scenario A, assuming a 15% increase in the average frequency and height of the significant wave, the forecast of coastal transport is 138-161 thousand m3/year, for Scenario B (30%) 150-175.5 thousand m3/year, and for Scenario C (50%) 180-210 thousand m3/year. In addition, the aim of the work is a cause-and-effect analysis of wave activity on the coast of the Gulf of Gdańsk and the assessment of its impact on quantitative changes in the sediment transport balance.

18

Blade cup method for cavitation reduction in marine propellers

Samsul M. Burak

Polish Maritime Research

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2021

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nr 2

54--62

EN

Energy efficiency has become more important in every industry and daily life. Designing and building a more efficient marine vehicle can lead to lower fuel consumption and a longer lifetime for the components of the vehicle. Erosion caused by cavitation reduces the service life of the propeller and the related components in the propulsion and maneuvering system. Reducing cavitation leads to a longer life for these components. This paper aims to explain and investigate propeller blade cup as a cavitation reduction method for marine propellers. A cavitating no-cup propeller is created and analyzed then the cupped version of this propeller is generated and analyzed to compare with the no-cup propeller. Cavitation results of these propellers are investigated. In addition, the thrust, torque, and efficiency of the propellers are compared.

19

Wpływ czasu użytkowania na właściwości włóknin Maliwatt stosowanych jako zabezpieczenie przeciwerozyjne skarp

Grzybowska-Pietras Joanna, Derbin Patrycja

Polish Journal of Materials and Environmental Engineering

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2021

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Vol. 2 (22)

30--38

EN

The additional artificial elements have been implemented into weak soil to improve and stabi-lize the structures. The most frequent example is use of geosynthetics materials that in-crease stability, improve bearing capacity of soil, protect against surface erosion, affect into properties connected with filtration and drainage. The basic methods to protect against ero-sion of slopes is selected planting of grass and vegetation that prevent surface destruction. The application of biodegradable geotextiles allows to increase the positive impact on local stability of slopes. Advanced geotextiles support the vegetation growth by protection against dewatering. The geotextiles with grass seeds, biomates and fabrics made of natural fibers are frequently used in these applications. The physical, mechanical and hydraulic properties of applied materials should correspond to the purpose of built structure and type of soil. The paper presents results of research of the Maliwatt type nonwovens. The analysis in-cludes: the influence of different type of Maliwatt nonwovens and time of their use on select-ed physical, mechanical and hydraulic properties of these materials. The research was done by use of biotextile stitched with the Maliwatt technique that is available on the Polish market. The geotextiles were obtained from waste synthetic and natural nonwovens (RKL) with grass seeds, and innovative non-woven fabrics stitched with polyamide yarn (Maliwatt) obtained from low-quality washed sheep wool. The impact of the type of non-woven fabric on the growth of grasses was also analyzed. Research included spreading of 2 types of nonwovens on a natural slope with natural soil cover for 5 months period. All tests were performed in ac-cordance with the applicable harmonized standards.

20

Renaturyzacja rzek szansą dla ochrony populacji brzegówki Riparia riparia w Polsce

Michalicha Mateusz

Polish Journal for Sustainable Development

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2021

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T. 25, cz. 1

43--56

PL

Regulacja i przebudowa rzek oraz ich dolin, oprócz drastycznych zmian hydrologicznych, często prowadzą do zmiany lub zaniku siedlisk cennych gatunków roślin i zwierząt. Szczególnie narażone na utratę miejsc rozrodu są gatunki bezpośrednio związane z urwistymi brzegami oraz skarpami nadrzecznymi, które powstają w wyniku procesów erozyjnych oraz osuwiskowych. Stosowane intensywne zabiegi hydrotechniczne takie jak prostowanie koryt czy likwidacja nieregularności brzegów powodują zahamowanie naturalnych, procesów rzecznych, które są pożądane. Gatunki ptaków występujące w Polsce, potrzebujące do gniazdowania naturalnych wysokich brzegów, to m. in.: brzegówka Riparia riparia, zimorodek Alcedo atthis oraz żołna Merops apiaster. Coraz liczniej podejmowane są działania, prowadzące do przywrócenia rzekom stanu zbliżonego do naturalnego. Celem renaturyzacji jest nie tylko zwiększenie możliwości retencyjnych, ochrona przed powodziami, lecz także ogólna poprawa funkcjonowania ekosystemów rzecznych oraz zachowanie bioróżnorodności w obrębie ich dolin. Renaturyzacja obejmuje działania takie jak: tworzenie odsłoniętych skarp, naśladujących podcięcia erozyjne, likwidacja umocnień brzegów czy utrzymanie wyrw brzegowych. Oprócz drapieżnictwa, ze strony takich gatunków jak norka amerykańska Neovison vison, lis Vulpes vulpes oraz lokalnie jenot Nyctereutes procyonoides, największym zagrożeniem dla populacji brzegówki jest utrata odpowiednich miejsc rozrodu. Uregulowanie rzeki, gdzie wprowadzone zabiegi hydrotechniczne spowodowały zaburzenie funkcjonowania naturalnych procesów rzecznych, powoduje również straty w lęgach ptaków przez gwałtowne powodzie, które niszczą gniazda wraz z jajami lub pisklętami. Brzegówki w wielu miejscach zaprzestały użytkowania koryt rzecznych jako miejsc lęgowych, zajmując antropogeniczne siedliska, które mają jednak pewne ograniczenia i zagrożenia. Renaturyzacja jest więc ważnym działaniem, które należy podjąć w miejscach, gdzie regulacje w przeszłości przyniosły największe szkody w środowisku. Należy wspierać rozwój terenów antropogenicznych w zgodzie z zasadami zrównoważonego użytkowania zasobami środowiska naturalnego.

EN

The regulation and reconstruction of rivers and their valleys, apart from drastic hydrological changes, often lead to the change or disappearance of the habitats of valuable plant and animal species. Particularly vulnerable to the loss of breeding sites are species directly associated with precipitous banks and river slopes, which are formed as a result of erosive and landslide processes. Intensive hydrotechnical treatments, such as straightening of the channels or elimination of irregularities of the river banks, resulted in the inhibition of the desirable natural river processes. Bird species native to Poland that require the above nesting conditions, include: sand martin Riparia riparia, kingfisher Alcedo atthis and bee-eater Merops apiaster. More and more actions are taken to restore rivers to a near-natural state. The aim of restoration is not only to increase retention capacity, protect against floods, social and economic benefits, but also to improve the overall functioning of river ecosystems and preserve biodiversity within their valleys. Renaturation includes activities such as the creation of exposed slopes that mimic erosive undercuts, the removal of bank reinforcements or the maintenance of bank gaps, which promote their occupation by the aforementioned bird species. In addition to predation, the loss of suitable breeding sites is the greatest threat to the sand martin population, such as the American mink Neovison vison, the fox Vulpes vulpes and the locally raccoon dog Nyctereutes procyonoides. A regulated river, where the implemented hydrotechnical measures disrupt the functioning of natural river processes, also causes losses in bird broods due to flash floods that destroy many nests together with eggs or nestlings. Sand martins in many places have stopped using riverbeds as breeding places, occupying anthropogenic habitats which, however, have certain limitations and threats. Renaturation is therefore an important measure to be taken in places where past regulations have caused the greatest damage to the environment. The development of anthropogenic areas should be supported in accordance with the principles of sustainable use of natural resources.