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1

Rola scaleń gruntów i zabiegów przeciwerozyjnych w poprawie efektywności wapnowania gleb

Pijanowski Jacek M., Janus Jarosław, Kowalik Tomasz, Nicia Paweł, Wojewodzic Tomasz, Dacko Mariusz, Płonka Aleksandra, Zadrożny Paweł, Paluch Łukasz

Przegląd Geodezyjny

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2023

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R. 95, nr 4

15--20

PL

Niniejszy artykuł powstał na bazie badań dotyczących wpływu układu przestrzennego gruntów ornych na efektywność wapnowania gleb, prowadzonych w ramach projektu pn. „Możliwości i bariery wykorzystania wapnowania gleb do poprawy efektywności ekonomicznej produkcji rolnej oraz ograniczenia eutrofizacji wód powierzchniowych” realizowanych przez zespół ekspertów z Uniwersytetu Rolniczego w Krakowie. Chociaż głównym przedmiotem badań było określenie czynników, jakie wpływają na niedostateczny poziom stosowania przez rolników nawozów wapniowych w uprawie roli, to analizowano również wpływ układów gruntowych i kierunku uprawy na efektywność wapnowania gleb. Obserwacje i analizy w tym zakresie zrealizowano w małopolskiej gminie Polanka Wielka (powiat oświęcimski). Wyniki tych prac pozwoliły na stwierdzenie, że wzdłużstokowy kierunek uprawy gruntów ornych nawet na terenach o niezbyt dużych deniwelacjach terenu, w przypadku gdy przestrzeń rolnicza pozbawiona jest naturalnych przeszkód dla spływu wody lub zabiegów przeciwerozyjnych, znacząco obniża efektywność wapnowania gleb. Scalenia gruntów mogą w takich przypadkach stanowić ważne narzędzie poprawy efektywności nawożenia wapniowego oraz zapobiegać utracie cennych składników pokarmowych z gleby. Wyniki prac badawczych posłużyły do sformułowania wniosków i rekomendacji.

EN

This article is based on research about the impact of the spatial arrangement of arable land on the effectiveness of soil liming, conducted as part of the project entitled "Possibilities and barriers to the use of soil liming to improve the economic efficiency of agricultural production and reduce the eutrophication of surface waters" carried out by a team of experts from the University of Agriculture in Krakow. Although the main subject of the research was to determine the factors that affect the insufficient level of use of calcium fertilizers by farmers in soil cultivation, the impact of parcels arrangement and cultivation direction on the effectiveness of soil liming was also analysed. Observations and analyzes in this regard were carried out in the Malopolska's commune of Polanka Wielka (Oświęcim poviat). The results of these works allowed to conclude that the longitudinal direction of arable land cultivation, even in areas with not very large terrain denivelations, when the agricultural space is devoid of natural obstacles to water runoff or anti-erosion treatments, reduces the effectiveness of soil liming. In such cases, land consolidation can be an important tool to improve the effectiveness of calcium fertilization and prevent the loss of valuable nutrients from the soil. The results of the research work were used to formulate conclusions and recommendations.

2

The estimation of water erosion with RUSLE and deposition model : A case study of the Bin El-Ouidane dam catchment area (High Atlas, Morocco)

Nouaim Wafae, Rambourg Dimitri, El Harti Abderrazak, Ettaqy Abderrahim, Merzouki Mohamed, Karaoui Ismail

Journal of Water and Land Development

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2023

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no. 58

136--147

EN

Water erosion is a critical issue for Morocco, especially in its semi-arid regions, where climatic and edaphic conditions only allow erratic soil formation and vegetation growth. Therefore, water erosion endangers human activity both directly (loss of arable land, landslides, mudflows) and indirectly (siltation of dams, river pollution). This study is part of the Kingdom’s effort to assess the risk of water erosion in its territory. It is dedicated to the Bin El-Ouidane dam water catchment, one of the biggest water storage facilities in the country, located in the High Atlas Mountains. The poorly developed soils are very sensitive to erosion in this mountainous area that combines steep slopes and sparse vegetation cover. The calculation of soil losses is carried out with the RUSLE model and corrected by estimating areas of deposition based on the unit stream power theory. This method produces a mean erosion rate of around 6.3 t·ha-1·y-1, or an overall annual loss of 4.1 mln t, consistently with the siltation rate of the dam. Primary risk areas (erosion rates > 40 t·ha-1·y-1) account for 54% of the total losses, while they cover only 7% of the catchment. This distribution of the soil losses also shows that the erosion risk is mainly correlated to slope, directing the means of control toward mechanical interventions.

3

GAEC 5 Direct Payment System Implementation Challenges in Slovakia

Pipíšková Petra, Muchová Zlatica, Dežerický Dávid, Michal Peter

Journal of Ecological Engineering

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2023

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Vol. 24, nr 6

109--118

EN

The Agricultural Payments Agency (supervisory and registry authority) of the Slovak Republic has announced an erosion hazard layer to meet the requirements of GAEC5 (Minimising soil erosion. Limit soil erosion by putting in place suitable practical measures). If a farmer fails to observe the layer data, they will be fined and might lose access to direct subsidies (also known as direct payments). The layer that has been announced raises a number of questions and concerns amongst beneficiaries of direct subsidies and users of land parcels. For instance, with the Pastuchov land parcel, the uncertainties associated with the application of GAEC5 were raised. A comparison of the water erosion layer commitment for 2023 with the erosion calculated by the Universal Soil Loss Equation (USLE) method based on the Digital Relief Model (DRM) generated from airborne laser scanning has confirmed the uniformity in all classified categories of water erosion over a 65% land parcel area. The situation of the land user has been diminished (i.e. they have to comply with GAEC5 even when there is no reason to) over 11% of the area. The situation of the land user has improved over 24% of the area (i.e. they do not have to comply with the conditions even when there is reason to). This paper describes the problems and outlines the possibilities for the necessary adjustment of compliance with the GAEC5 conditions in Slovakia.

4

Temporal Analysis of Erosion Risk Classes and Rates in the Wadi Ouergha Watershed, Northern Morocco

Naoui Basma, Titafi Asmae, Baghdad Bouamar, Chakiri Saïd, Sadiki Mohamed, Zerdeb Mohammed Amine, El Omari Mariyam, Lididi Sara

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 9

150--160

EN

The significance of the issue lies in the pivotal role played by Wadi Ouergha, as a major tributary of Wadi Sebou. This watercourse directly contributes to the El Wahda dam, the largest in the Kingdom of Morocco and the second largest in Africa. With its substantial storage capacity and noteworthy annual sedimentation volume, this dam’s storage capacity is notably impacted. The ongoing decline in the capacity of the El Wahda dam could potentially accelerate due to shifts in surface water mobilization rates and the worsening degradation of marl soils within the catchment, coupled with alterations in vegetation cover. The aim of this study is to examine the changes in the erosion rate within the Wadi Ouergha watershed over a span of 40 years, covering the periods 1980–2000 and 2001–2020. This comparative analysis aims to ascertain whether erosion control measures have effectively reduced the erosion rate in the region over time. To assess soil losses occurring in the Wadi Ouergha watershed, impacting the El Wahda dam, we employed the RUSLE model to determine the rate and vulnerability of the catchment to water erosion. The results indicate that erosion control measures have been effective in combating soil erosion in the potential region with high erosion risk, with a 13.83% reduction in the average erosion rate between the two periods, from 25.3 to 21.8 (tons/hectare/year). This study presents a groundbreaking contribution by unveiling, for the first time, the dynamic evolution of water erosion patterns over time. It offers a comprehensive assessment of the effectiveness of erosion control measures implemented within the most vulnerable zones.

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Contribution of Geomatics and Remote Sensing to Environmental Study in the Cretaceous Basin of Errachidia-Boudenib (Morocco)

Mehdaoui Radouan, Mili El-Mostafa, Ousmana Habiba, Said Brahim Ait, El Khamal Youssef, Aziz Hachem, El Fakir Rabia

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 1

196--206

EN

The present study aims at mapping areas vulnerable to water erosion based on the Priority Activity Program/Regional Activity Center (PAP/CAR) model guidelines, geomatics, remote sensing, and GIS in the Errachidia-Boudenib Cretaceous basin. This basin is located in south-eastern Morocco and covers an area of 13 000 km2, the basin is 320 km long and 75 km wide. The method of estimating water erosion is composed of three phases; a predictive phase consisting of a mapping of predisposing factors such as slope, substrate, and/or soils and vegetation cover, a descriptive phase based on the mapping of actual erosion, and an integration phase to arrive at the identification and evaluation of the erosion risk. The mapping of areas vulnerable to water erosion indicates that 70% of the studied basin has low erodibility and 22% is notable, while only 8% has high to very high erodibility. The areas most affected by degradation are located at the end of the basin and correspond to lands with steep slopes (>35%). Consequently, this study has allowed us to locate certain sectors and roads that may be affected by this type of erosion, namely the mountainous areas of the High Atlas and roads numbered R13, R601, R 703, and P7106.

6

Analysis and Mapping of Water Erosion Vulnerability Using GIS for the Mghila Watershed, Northwest of Algeria

Ratiat Abdelkader, Haddad Ali, Bouaichi Ilham, Matene Chahrazed Naziha

Archives of Hydro-Engineering and Environmental Mechanics

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2023

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Vol. 70, nr 1

71--87

EN

Intensification of extreme rainfall-runoff events in arid and semi-arid regions because of climate change induce the water erosion that contributes considerably to the loss of vegetal layers of soils and reduce the storage capacity of dams by silting of transported sediments from the watershed to the impoundment. This paper aims at proposing means for protecting the Mghila dam against silting by identification and delimitation of vulnerable areas to water erosion. This dam, built in the North-West of Algeria, ensures irrigated cultivation. Topographical, geological, and land use characteristics of the watershedwere analyzed using the geographic information system (GIS). Analysis of results has allowed the identification by area percentage four-vulnerability classes with sensitivity to the water erosion: low (18.89%), medium (13.08%), high (65.05%) and very high (8.38%). The spatial distribution of the lithological substratum friability, the vegetation cover and slope degrees have led to the development of an efficient strategy for the watershed management in order to reduce the effect of water erosion on soil degradation and silting of the Mghila dam.

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Diachronic mapping and evaluation of soil erosion rates using RUSLE in the Bouregreg River Watershed, Morocco

Moudden Fouad, El Hafyani Mohammed, El Ouali Anas, Roubil Allal, El Ouali Abdelhadi, Essahlaoui Ali, Brouziyne Youssef

Journal of Water and Land Development

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2022

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no. 53

86--99

EN

Soil erosion has been severely affecting soil and water resources in semi-arid areas like the Mediterranean. In Morocco, this natural process is accelerated by anthropogenic activities, such as unsustainable soil management, overgrazing, and deforestation. With a drainage area of 395,600 ha, the Bouregreg River Watershed extends from the Middle Atlas Range (Jebel Mtourzgane) to the Sidi Mohamed Ben Abdellah (SMBA) dam reservoir south-east of Rabat. Its contrasted eco-geomorphological landscapes make it susceptible to unprecedented soil erosion due to climate change. Resulting changes in erosive dynamics led to huge amounts of solid loads transported to the catchment outlet and, thus, jeopardised the SMBA dam lifespan due to siltation. The research aims to quantify the average annual soil losses in this watershed using the Revised Universal Equation of Soil Losses (RUSLE) within a GIS environment. To highlight shifts in land use/land cover patterns and their effects on erosional severity, we have resorted to remote sensing through two Landsat 8 satellite images captured in 2004 and 2019. The C factor was combined with readily available local data regarding major erosion factors, e.g. rainfall aggressiveness (R), soil erodibility (K), topography (LS), and conservation practices (P). The helped to map the erosion hazard and determine erosion prone areas within the watershed where appropriate water and conservation measures are to be considered. Accordingly, from 2004 to 2019, average annual soil losses increased from 11.78 to 18.38 t∙ha-1∙y-1, as the watershed area affected by strong erosion (>30 t∙ha-1∙y-1) evolved from 13.57 to 39.39%.

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Assessment of soil erosion using the GIS-based erosion potential method in the Kebir Rhumel Watershed, Northeast Algeria

Zeghmar Amer, Marouf Nadir, Mokhtari Elhadj

Journal of Water and Land Development

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2022

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no. 52

133--144

EN

Soil erosion is an important factor that should be considered when planning renewable natural resource projects, effects of which can be measured by modelling techniques. Therefore, disintegration models determine soil loss intensity and support soil conservation practices. This study estimates soil loss rates by water erosion using the Erosion Potential Method (EPM) in the Kebir Rhumel Watershed located in Northeast Algeria. The area is north to south sub-humid to semi-arid, receives irregular rainfall, and has steep slopes and low vegetation cover which makes it very vulnerable to erosion. The main factors in the EPM (soil erodibility, soil protection, slope, temperature, and rainfall) were evaluated using the Geographical Information System (GIS) and data provided by remote sensing technologies. The erosion intensity coefficient Z was 0.60, which indicates medium erosion intensity. While the results showed the average annual soil erosion of 17.92 Mg∙ha-1∙y -1, maximum and minimum losses are 190.50 Mg∙ha-1∙y-1 and 0.21 Mg∙ha-1∙y-1, respectively. The EPM model shows satisfactory results compared to some studies done in the basin, where the obtained results can be used for more appropriate management of land and water resources, sustainable planning, and environmental protection.

9

Assessing the intra-annual variability of agricultural soil losses: a RUSLE application in Nord-Pas-de-Calais, France

Nouaim Wafae, Rambourg Dimitri, Merzouki Mohamed, El Harti Abderrazak, Karaoui Ismail

Journal of Water and Land Development

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2022

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no. 52

210--220

EN

The control of water erosion is an important economic and societal challenge. Reduction of the agronomic potential of the parcels, muddy flows, siltation of dams are harmful consequences that mobilize farmers, water managers, local authorities and scientific researchers. This study focuses on mapping and quantifying seasonal soil losses in the territory of the former Nord-Pas-de-Calais administrative region, using the Revised Universal Soil Loss Equation (RUSLE) which incorporates five factors: rainfall erosivity, soil erodibility, topography, land use and erosion control practices. The seasonal (3-months) time scale is chosen to better account for the parameters governing the soil water erosion, especially rainfall and vegetation cover, that show great asynchronous intra-annual variability. Also, high resolution data concerning agricultural plots allows to evaluate which type of culture are the more subject to soil losses. In Nord-Pas-de-Calais, water erosion occurs almost ubiquitously, but the areas characterized by steep slopes are the most at risk (Artois Hills and Flanders), with loss rates up to 54 t∙ha-1∙y-1. The majority of erosion occurs during fall (46% of the computed annual losses of 1.69∙Mt), on plots left bare after harvest (especially corn and beets crops). The study also demonstrates that extending the intercrop technique over the region, and therefore maintaining a fall and winter cover, could reduce the soil losses by 37%.

10

Comparison of the Methods for LS Factor Calculation when Evaluating the Erosion Risk in a Small Agricultural Area Using the USLE Tool

Karásek Petr, Pochop Michal, Konečná Jana, Podhrázská Jana

Journal of Ecological Engineering

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2022

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Vol. 23, nr 1

100--109

EN

In the projects of anti-erosion protection in the Czech Republic, USLE was used as a standard tool for evaluating the risk of water erosion. The precision of the resulting USLE values is defined by the quality of input data and algorithms used. Two methods for LS factor calculation are recommended for use in the planning practice in the Czech Republic: the computing method based on the USLE 2D software and the other computing methods. Various methods can assess the LS factor; however, their results differ. On the example of the Starovice – Hustopeče study area (Czech Republic), strongly threatened by erosion, this report aimed to show the differences brought using these differing methods of LS factor assessment, all in two variants before and after application of antierosion measures (retention grass belts, grassed thalweg). Changes in the calculation of the LS factor were directly reflected in the calculation of the long-term average soil loss by water erosion.

11

Quantification and Evaluation of Water Erosion by RUSLE/GIS Approach in the Ykem Watershed (Western Morocco)

Aoufa Mohameden, Baghdad Bouamar, El Hadi Hassan, Chakiri Saïd, Hamoud Ahmed, Zoraa Noura, Zerdeb Mohammed Amine, Moussa Karima

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 5

42--53

EN

The Water erosion of soils considered the main cause of soil degradation in Morocco. Soil erosion not only reduces agricultural productivity but also reduces water availability, and negatively contributes to the quality of drinking water sources. Consequently, the assessment of soil erosion risk has become the objective of several researches at the Moroccan level. It is in this context the purpose of this study is to assess the soil erosion risk using a Revised Universal Soil Loss Equation (RUSLE) / Geographic Information System (GIS) approach at the scale of the watershed of the Oued Ykem (western Morocco). (GIS) techniques were adopted to process the data obtained at the watershed scale, of reasonable spatial resolution (30 m) for the application of the RUSLE model. The latter is a multiplication of the five factors of erosion: the rainfall erosivity (R), the soil erodibility (K), the slope length and steepness (LS), the cover and management and the support practice (P). Each of these factors has been expressed as a thematic map. The Oued Ykem watershed is an elongated coastal basin with an area of 516 km2. It is part of the Atlantic coastal basins of western Morocco. It is located southwest of the city of Rabat. Oued Ykem is characterized by a semi-arid climate with oceanic influence. Rare and irregular rains, mostly stormy in nature, combined with deforestation, cause erosion and irregular flow. Its flow-rate increases during the winter. Extreme flows-rate can be recorded after exceptional and very intense showers upstream of the basin. The resulting soil loss map, with an average erosion rate varying from 0 to 54 t/ha/year, showed low erosion. Areas with a strong erosion rate exceeding 30 t/ ha/ year cover about 3.8 % of the basin area. The analysis of the erosion risk map, in comparison with the maps of the different factors in the equation, showed a clear and important influence of the vegetation cover on the soil erosion (C factor is from 0.03 to 0.9), followed by the topographic factor, especially the slope (LS factor varies from 0 to 56.71).

12

Environmental and economic effects of water and deflation destruction of steppe soil in Ukraine

Dudiak Nataliia, Pichura Vitalii, Potravka Larisa, Stratichuk Natalia

Journal of Water and Land Development

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2021

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no. 50

10--26

EN

Water and wind erosion are the most powerful factors in the decrease of soil fertility and a threat to food security. The study was conducted on the steppe zone in Ukraine (total area of 167.4 thous. km2), including agricultural land (131.6 thous. km2). At the first stage, the modeling of spatial differentiation of water and wind erosion manifestations was carried out to calculate losses of soil (Mg∙ha–1) and to determine their degradation. At the second stage, soil-climatic bonitet of zonal soils (points) is carried out to determine their natural fertility (Mg∙ha–1). At the third stage, the spatial adjustment of the natural soil fertility to the negative effect of erosion was carried out. This made it possible to calculate crop losses and total financial losses due to water and wind erosion. The integrated spatial modeling showed that about 68.7% of arable land was constantly affected by the combined erosion, in particular the area of low eroded arable land (16.8%), and medium and highly eroded land (22.1%). Due to erodibility of soil, about 23.3% of agricultural land transferred from the category of high and medium quality to medium, low and very low quality, which is caused by the loss of soil fertility of up to 70%, crop losses of up to 1.93 Mg∙ha–1 ha–1 and eduction of agricultural income up to 390 USD∙ha–1. In the steppe region under the research, gross crop losses from erosion were up to 15.11 thous. Mg∙ha–1 (3.05 mln USD). In order to protect soils, improve fertility and increase crop yields in the steppe zone in Ukraine, the following measures were suggested: adaptive and landscape erosion control design with elements of conservation farming in accordance with the spatial differentiation of soil quality and extent of water erosion deflation danger.

13

The impact of precipitation on state of the slopes surface and thermal activity of the mine waste dump - preliminary study

Różański Zenon, Wrona Paweł, Pach Grzegorz, Niewiadomski Adam, Suponik Tomasz, Frączek Robert, Balcarczyk Leszek

Journal of Sustainable Mining

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2021

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Vol. 20, iss. 1

2--12

EN

Precipitation, especially with a high intensity, affects the condition of mining waste dumps. The article presents the results of research aimed at determining the impact of rain on water erosion on the slopes of a coal waste dump and its thermal state. Preliminary tests of the condition of two slopes of the coal waste dump in Libiąż (Poland) undertaken in the frameworks of the TEXMIN project was carried out using modern geodesy techniques (low-ceiling photogrammetry and TLS terrestrial laser scanning). The current geometry of the slope surface was faithfully reproduced in the form of a cloud of points with known coordinates x, y, z. The thermal state within the analyzed slopes of the dump was also assessed. Based on thermography studies and measurements of temperature and gas concentrations inside the object, two zones of thermal activity were located on one of the examined slopes. The test results constitute the initial state against which the results of further tests will be compared. This will allow to determine the influence of precipitation on the amount of water erosion and the thermal state of the dump in a specific time period.

14

Environmental Effects of Reducing Land Fragmentation in Land Consolidation at West Roztocze at the Slope Scale

Rybicki Roman

Journal of Ecological Engineering

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2021

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Vol. 22, nr 1

240--248

EN

The paper presents the ecological effects of land consolidation carried out in upland loess areas. The design of a large plot of land on a slope with a gradient of up to 18% and its impact on the intensity of water erosion were investigated. The analyzed plot was created by consolidation 12 smaller plots. Before the consolidation, all plots had a cross-slope layout and direction of agrotechnical operations. Exactly the same arrangement remained after the consolidation. The WEPP simulation model was used for the comparison of the pre-consolidation and postconsolidation state. The amount of soil loss and sediment yield was estimated under different scenarios of slope management. It was found that after consolidation (creation of a plot with the width of more than 130 m), as a result of removing of terraces and sodded cross-slope scarps, the intensity of erosion increased many times. In order to restore the anti-erosion effect of cross-slope cultivation on such a slope without increasing the difficulties of agrotechnics, it is necessary to restore the sodded scarps that existed before consolidation. The simulation results show that the scarps should be located transversely to the slope (along the plot) in the middle and lower parts of the slope, in the place of the highest inclination. As advantage of the consolidation project was considered the elimination of longitudinal balks which were focuses of linear erosion on the slope.

15

Water Erosion Mapping by RUSLE: A Geomatic Approach by GIS and Remote Sensing in the Oued Isser Watershed, Tlemcen, Algeria

Talbi Okacha, Fatmi Belaïd, Benhanifia Khatir, Talbi Djilali

Geomatics and Environmental Engineering

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2021

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Vol. 15, no. 2

89--104

EN

Prolonged water erosion leads to severe soil degradation, with highly visible scars. Consequently, the quantitative and descriptive estimation by mapping of the phenomenon has become the main objective of a great deal of research. It is this perspective that this study takes, based on the Revised Universal Soil Losses Equation (RUSLE) for a relatively accurate estimate, by integrating Arc GIS tools and remote sensing using high spatial resolution (10 m) image from the Sentinel 2A satellite. The model uses data on precipitation, soil, topography and vegetation cover management. The methodological approach taken implements this model in order to optimize its use by the various potential users in their planning and decision making studies. An application was carried out in the Oued Isser watershed (Tlemcen, Algeria). Soil loss maps were produced and the results indicate a high variation in soil losses in the study area and show that the highest values are concentrated on steep slopes, hence the great influence of the topographic parameter relative to other factors in the model.

16

Sekularne i ekstremalne procesy erozji wodnej gleb na Pojezierzu Drawskim

Majewski Mikołaj

Landform Analysis

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2020

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Vol. 39

1--106

EN

Soil erosion by water is one of the most important factors affecting contemporary landscape changes within the lowland geoecosystems in Central Europe. Soil erosion by water mainly depends on: rainfalls (especially its intensity and erosivity), length of slope and its inclination, type of cultivation and usage of land, anti-erosion treatments and susceptibility of soils to erosion. The aim of conducted research was to evaluate conditioning and magnitude of secular and extreme soil erosion processes in the Drawsko Lakeland with special considering of rainfall erosivity index (EI30). The main goal was realised through several research tasks. The first task involved examination of surface runoff and slope wash conditionings, course and quantity in the testing plot located within the Chwalimski Potok catchment. The second task was related to evaluate rainfall impact to soil erosion by water processes. It was realised by computation rainfall characteristics: intensity, kinetic energy and erosivity. In order to assess secular and extreme soil erosion impact to land relief changes, research were provided with additional details by conducting three field experiments with simulated rainfall. Stationary observation and quantitative researches of soil erosion (at testing plots) have been conducting within the Chwalimski Brook catchment for three hydrological years (2012–2014). The slope with the test area is located within the 1st order catchment being a subsystem of the Młynski Brook catchment and then followed by the upper Parsęta catchment. This area covers 4.8 hectares and is characterised by short slopes with small height variances up to 10 meters. Historically, the area was covered with agricultural crops, currently they cover about 10% of the area. The slope is covered with gleyic retisols and its average inclination is about 4 degrees with its south-east exposure. The measuring system of soil erosion covered 5 testing plots with different agricultural use (bare fallow, meadow, potatoes, spring and winter crops). Plots are 42 metres long and 4 metres width. In the bottom edge of each plot catchers with volume of 800 dm3 were installed. In this research, only data from black fallow were considered. Such tillage is recognised as a standard in soil erosion studies. Two experiments have been conducted in this testing plot. The third one has been conducted on slope located within an area of undulated morainic plateau in the Kłuda catchment. The slope is characterised by greater height variances than in Chwalimski Brook catchment. The slope, where the experiment has been conducted, is situated within local closed depression and is covered by sands underlain by boulder clay. Its average slope is about 10° with its southwest exposure. Although annual precipitation in the three-year measurement period was comparable with mean value from multi-year period (1987–2014), its intensity and erosivity were distinguishably lower. Such rainfall conditions are not favourable for extreme soil erosion by water processes, thus any relief forms from such geomorphological processes were not observed in the Drawsko Lakeland. Due to lack of that kind of forms, in 2013 and 2014, three field experiments were conducted. The main aim of experiments was to evaluate the impact of high intensity rainfall on soil surface. The first experiment consisted of 5, the second and the third of 4 rainfall simulations. The rainfall was created by using a purpose-built rain simulator, consisting of 3 and 6 sprinklers placed around the testing plot. Despite the slope inclination in the Kłuda catchment was 2.5 times steeper than Chwalimski Potok’s slope, surface runoff attained smaller volume, because of remarkably higher infiltration rate. In 2012–2014, surface runoff and soil loss has occurred 8 times each year. The maximal monthly surface runoff volume was registered in February 2012, and it equalled 10.1 dm3 m−2 and the maximal soil loss value was registered in May 2013 and equalled 3,198 kg ha−1. Annual runoff volumes were between 31.2 dm3 m−2 in 2012 and 38.8 dm3 m−2 in 2013, whereas annual soil loss values ranged from 740 kg ha−1 in 2012 to 5,700 kg ha−1 in 2013. Soil erosion values caused by simulated rainfall during field experiments were similar or significantly higher than annual values. Surface runoff was between 31.2 dm3 m−2 in the first experiment and 34.2 dm3 m−2 in the second one, whilst soil loss was between 4,632 kg ha−1 and 8,637 kg ha−1. The achieved experiment results have been compared with soil erosion rate achieved from stationary observations. The results show that runoff and soil loss considerably increase during rainfalls with high amount, intensity and erosivity. Furthermore, individual extreme erosive events may exceed annual (secular) soil erosion processes. Conducted stationary research indicates that annual soil erosion primarily depends on individual rainfall and erosive events, which considerably exceed mean values. In order to evaluate the soil susceptibility to erosion by water in the Drawsko Lakeland, high resolution potential and actual soil erosion risk maps were prepared. The qualitative assessment of soil erosion risk was based on geoinformation technologies. The model considers following conditions affecting the size of soil erosion: slope steepness and aspect, topographic factor LS (unit upslope contributing area), lithology, rainfall erosivity (Modified Fournier Index calculated from monthly and annual precipitation data) and land use and land cover from Corine Land Cover 2006. To prepare the map of potential soil erosion risk, land use from Corine Land Cover was not considered. Thematic maps have been reclassified into a 4-degree division. The results of the soil erosion risk assessment in the Drawsko Lakeland reveal the fact that a majority of its area is characterized by moderate or low erosion risk levels. Areas with high erosion risk are mostly located in the northern part of the Lakeland. The achieved results from stationary observations and field experiments may indicate that the soil loss magnitude significantly increases during rainfall with higher intensity, greater totals and accumulated in time rainfall events. This may confirm the high potential of soil erosion by water processes of above- -average magnitude and intensity in the discharge of material from agricultural used slopes.

17

Spatialization of water erosion using analytic hierarchy process (AHP) method in the high valley of the Medjerda, eastern Algeria

Belloula Moufida, Dridi Hadda, Kalla Mehdi

Journal of Water and Land Development

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2020

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no. 44

19--25

EN

The present study tries to quantify soil losses using Geographic Information Systems (GIS) and analytic hierarchy process (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 vulnerability, areas with very high to high vulnerability are mainly in the northern part of the watershed (where the relief is very important).

18

Predicting water erosion in arid lands using the GIS-based RUSLE model: A case study of Bedour catchment, central Tunisia

Bedoui Chokri

Journal of Water and Land Development

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2019

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no. 40

59--66

EN

This study was conducted with a view to quantifying soil erosion in arid lands of Tunisia. To do this, we have opted to use the RUSLE model based on geographic information systems. By collecting data on rainfall, soils, vegetation, slopes and conservation practices separately as a layer and determining the pixel values for each of these factors, a quantified assessment of erosion in the basin is obtained. The data superposition and computing, following the model equations and protocol, allowed us to know the spatialized water erosion values at the pixel level. For the whole catchment, the study showed values oscillating between 0 and 163 Mg·ha–1·year–1 with an average annual rate of 3 Mg·ha–1·year–1. With such a low R (rainfall erosivity) factor (between 21.43 and 21.88 MJ·mm·ha–1·h–1·year–1) itself related to low monthly and annual rainfall amounts, the region experiences locally very high annual erosion rates. Soil protection through conservation practices has saved the basin from even higher erosion. While plains cultivated and equipped with contour benches often suffer from low rates of erosion (less than 2 Mg·ha–1·year–1), unused slopes are neglected without protection, resulting in significantly high rates of erosion.

PL

Badania prowadzono, aby ilościowo ocenić erozję gleby na suchych obszarach Tunezji. W tym celu wykorzystano model RUSLE bazujący na systemie informacji geograficznej. Zbiór danych, ich nakładanie i obliczenia prowadzono zgodnie z równaniami i protokołem modelu umożliwiły poznanie erozji w przestrzeni na poziomie pikseli. Badania wykazały, że w całej zlewni nasilenie erozji zmieniało się od 0 do 163 Mg·ha–1·rok–1 ze średnią równą 3 Mg·ha–1·rok–1. Mimo małego współczynnika R (erozyjność opadu), mieszczącego się w granicach 21,43–21,88 MJ·mm·ha–1·h–1·rok–1, który odzwierciedla niewielkie miesięczne i roczne opady, badany region doświadcza lokalnie bardzo wysokiego tempa erozji. Ochrona gleby poprzez odpowiednie działania uratowała zlewnię przed jeszcze większą erozją. Podczas gdy równiny uprawiane z ziemnymi ławami biegnącymi wzdłuż poziomic ulegają mniejszej erozji (mniej niż 2 Mg·ha–1·rok–1), nieuprawiane stoki są pozbawione takiej ochrony, co skutkuje wysokim tempem erozji.

19

The Assessment of the Amount of Soil Material Deposited on the Bottom of a Dry Erosive-Denudation Valley

Mazur Andrzej, Obroślak Radomir, Nieścioruk Kamil

Journal of Ecological Engineering

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2019

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Vol. 20, nr 11

210--216

EN

The work presents the results of research on erosion and landform changes of a bottom of a dry erosive-accumulation valley in Elizówka in 1958, 1970 and 2016. The changes have been examined with the use of geodetic topographic surveys techniques. The research field was a 480-metres long part of the valley bottom. The topographic surveys in 1958 and 1970 were conducted with longitudinal (parallel to the bottom of the valley) and cross (every 20 metres) sections method. In 2016 the modern measuring devices were used. All the results, together with coordinates of points and historical data were converted into GIS spatial layer. The altitude values formed the input data for interpolation of rasters showing changes of the topography in three periods. Three TIN models were also developed to distinguish erosion and accumulation zones plus the quantity of eroded and accumulated material. The valley on the majority of its length has been raised and has changed from V-shaped into U-shaped. Accumulation of the soil material led to levelling the bottom. Accumulation concentrates along a flow line, while soil washout mainly at the bottom of slopes. The thickest sediment layers were observed in the lowest part. For the whole 1958–2016 period a total of 3470 m3 soil material has been deposited on the area of about 1.62 ha, while in the same time only 130 m3 has been eroded (from 0.22 ha).

20

Geomodelling of Destruction of Soils of Ukrainian Steppe Due to Water Erosion

Dudiak Nataliia Vasylivna, Pichura Vitalii Ivanovich, Potravka Larisa Aleksandrovna, Stratichuk Natalia Vladimirovna

Journal of Ecological Engineering

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2019

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Vol. 20, nr 8

192--198

EN

Spatial raster distribution models of the values of factors influencing the potential soil erosion hazard were created using GIS technologies. The erosion hazard was estimated using the modified RUSLE (Revised Universal Soil Loss Equation) model. The potential of annual soil loss of arable land was calculated. The spatial gradation of erosion violation of administrative and territorial units in the steppe zone of Ukraine was provided. About 32.7% of arable land that is subject to high erosion hazard was allocated. About 48 administrative and territorial units have a specific area less than 5% of erosion disturbed lands. They are characterized by a resistant type of agrolandscapes regarding the water-erosion processes. Most administrative and territorial units with high erosive-accumulative potential (the percentage of the area is 15% or more) are located in the western and southwestern parts of the steppe zone of Ukraine. The specific area of erosion hazardous lands reaches up to 32% in separate administrative-territorial units. The obtained results allow determining the need for a spatially discrete-distribution implementation of adaptive-landscape anti-erosion design with the elements of soil-protective agriculture.