scholarly journals Water Erosion in the Moulouya Watershed and its Impact on Dams' Siltation (Eastern Morocco)

2021 ◽  
Vol 384 ◽  
pp. 127-131
Author(s):  
Abdelkader Sbai ◽  
Omar Mouadili ◽  
Mohamed Hlal ◽  
Khadija Benrbia ◽  
Fatima Zahra Mazari ◽  
...  
Keyword(s):  
Soil Cover ◽  
Water Erosion ◽  
Soil Protection ◽  
Slope Length ◽  
Adopted Model ◽  
Eastern Morocco ◽  
Carbonate Formations ◽  
Specific Degradation ◽  
Steep Slopes ◽  
Soil Losses

Abstract. The Moulouya watershed presents high risks of water erosion. The dams built on this river lose each year, by siltation, a volume of water of about 10 M m3 (Lahlou, 1994). This worrying rate shows that water erosion can hinder the socio-economic development of the basin if soil protection and siltation measures are not taken. This study defines the areas most threatened by water erosion to protect them as a priority. Using a GIS and the Universal Earth Loss Equation (USLE), we mapped soil losses. The adopted model determines soil loss from erosivity of rainfall, soil erodibility, inclination and slope length, soil cover, and erosion control practices. The possible origins of the deposits alluviating the dams are related to the products of alteration of the Secondary's carbonate formations and the Tertiary and Quaternary formations. The modalities of the transport of deposits of banks of the network of Moulouya are mainly by a suspension. The specific degradation in the Moulouya watershed is estimated at 214 t/km2/year. Precipitation intensity, steep slopes and deforestation are responsible for these losses.

scholarly journals Assessment and mapping of water erosion by the integration of the Gavrilovic “EPM” model in the Inaouene watershed, Morocco

2021 ◽  
Vol 314 ◽  
pp. 03009
Author(s):  
Laaraj Marouane ◽  
Benaabidate Lahcen ◽  
Mesnage Valérie
Keyword(s):  
Agricultural Land ◽  
Water Erosion ◽  
Soil Protection ◽  
The World ◽  
Soil Sensitivity ◽  
Middle Atlas ◽  
Control Water ◽  
Semi Arid ◽  
Soil Losses ◽  
Anthropic Pressure

Water erosion is one of the main causes of soil degradation around the world. In M orocco, In M orocco, the watersheds have very significant soil wastes, related to various physical and anthropic factors. The Oued Inaouene watershed is concerned because of its location in the eastern part of the Saïss basin, between the Middle Atlas and the Pre-Rif, where water erosion is more accentuated. This basin covers a total area of 3597.13 Km2 and it is marked by a semi-arid climate with relatively abundant (989.68 mm), irregular rainfall and strong anthropic pressure. This will have an impact of overexploiting natural resources in general and soils in particular. The excessive use of agricultural land has led to their fragility and aggravation of their susceptibility to erosion. These conditions, both natural and anthropic, have induced a rather intense erosive dynamic, which can be visible in its various forms, including gullying and landslides. The erosive dynamics leads progressively and certainly to impoverish the soils of the watershed and the silting of the dam Idris 1st located downstream of the Oued Inaouene, hence the interest of this study. The use of the “EPM” model for the estimation of soil losses approaches the severity of the erosive phenomenon. The average soil loss due to water erosion according to the model used is estimated at 53.34 t/ha/year. The maximum losses are about 597.642 t/ha/yr per plot. Total annual losses for the watershed are approximately 211084195 t/yr. Furthermore, the analysis of these results allowed, with the help of GIS, to determine the factors that control water erosion and which are, in order of importance: rainfall, slope, and soil sensitivity Soil protection. If anti-erosion measures aren’t adopted in the threatened parts of the watershed, this will have serious consequences for the dam and water quality .

scholarly journals DETERMINATION OF THE EROSIVE SUSCEPTIBILITY FROM A HYDROGRAPHIC BASIN USING FREE AVAILABLE GEO-TECHNOLOGY

GEOGRAFIA ◽  
2018 ◽  
Vol 42 (3) ◽  
pp. 57-70
Author(s):  
João Lucas Alves da SILVA ◽  
Vinícius de Oliveira RIBEIRO ◽  
Leonardo Lima dos SANTOS
Keyword(s):  
Soil Cover ◽  
Natural Process ◽  
Important Research ◽  
Slope Length ◽  
Mato Grosso ◽  
Hydrographic Basin ◽  
The City ◽  
Mato Grosso Do Sul ◽  
Soil Losses

Erosion is a natural process resulting from the interaction of rainfall and soil, which is enhanced by factors such as inadequate management of soil and removal of vegetation cover. This causes an excessive production of sediments, generating phenomena such as eutrophication and silting of watercourses. The Universal Soil Loss Equation (USLE), allows to estimate erosion under different land use/land conditions as well as under variable slope, slope length, soil types and rainfall. It allows the elaboration of thematic maps and it is an important research tool to analyze the erosive process. When applied with open and free available geo-technologies, it dramatically reduces the costs of performing the study. This study aimed to map and analyze qualitatively the erosive susceptibility of the Laranja Doce hydrographic basin, located in the city of Dourados / Mato Grosso do Sul State in the year of 2016, applying the USLE and geo-technologies that are available free on Internet. The average annual soil losses ranging 0-33 ton/ha/ year were obtained. Most of the area was classified with Low to Moderate Erosion since its erosive rate was lower than 15 ton/ha/year. It was observed that the spatial distribution of erosion is influenced especially by the soil cover and relief features described by the CP and LS factors, respectively

scholarly journals MODELING OF WATER EROSION IN A SUB-BASIN IN RIO GRANDE DO SUL USING THE RUSLE MODEL

2020 ◽  
Vol 28 ◽  
Author(s):  
Thais Palumbo Silva ◽  
Stefan Domingues Nachtigall ◽  
Maria Cândida Moitinho Nunes ◽  
Cláudia Liane Rodrigues Lima ◽  
Ana Paula Knapp
Keyword(s):  
Soil Loss ◽  
Soil Cover ◽  
Rio Grande ◽  
River Basins ◽  
Water Erosion ◽  
Rio Grande Do Sul ◽  
Cover Factor ◽  
Factor Data ◽  
Soil Losses ◽  
Soil Loss Equation

The intense use of farming land has caused many consequences to the environment, among them, water erosion. The scale study of river basins through modeling allows the identification and estimation of soil losses, aiming at the conservationist planning of the site. The objective of this work was to predict soil loss in the Micaela sub-basin, with an area of ??37 km2 located in the municipality of Pelotas, Rio Grande do Sul. For the prediction of soil loss, the Revised Universal Soil Loss Equation (RUSLE) was used. Erosivity was obtained from data from the literature and erodibility was estimated by means of the inherent soil attributes and the topographic factor calculated according to the accumulated flow and declivity in each pixel. For the cover factor, data from the literature were used, according to use recommendation and existing soil cover. The study area shows a strong erosivity, which ranged from 8,045 to 8,833 MJ mm ha-1 h-1 year-1. The Argissolos occupy 81.31% of the sub-basin and present high erodibility, varying from 0.0369 to 0.0422 Mg ha h ha-1 MJ-1 mm -1. The sites with the largest vegetation cover were those with the lowest soil losses. However, in more than 36% of the area, the soil losses are above the tolerable therehsold, indicating that they are more prone to degradation and, therefore, the systems of land use and adopted management should be reviewed.

THE PHYSICAL BASIS OF SOIL EROSION: MECHANISM, PATTERNS OF EXPRESSION AND PREDICTION

2021 ◽  
Author(s):  
Valeriy Demidov ◽  
Oleg Makarov
Keyword(s):  
Soil Erosion ◽  
Soil Cover ◽  
Physical Basis ◽  
Soil Science ◽  
Educational Institutions ◽  
Soil Protection ◽  
Erosion Mechanism ◽  
The Past ◽  
Erosion Processes ◽  
Wide Range

The monograph summarizes the information over the past 20 years on the currently widely used. The textbook is intended for students of higher educational institutions, studying in the specialty of soil science, as well as specializing in erosion and soil protection. The textbook describes the physical basis and mechanism of erosion processes, based on some sections of hydraulics, hydrology, hydro-and aeromechanics, knowledge of which is necessary to understand the mechanism of water, wind and irrigation soil erosion. The main mathematical models and principles of forecasting the values of soil losses as a result of erosion processes are considered. The textbook will be useful not only for students and postgraduates studying in the specialty of soil science, but also for geographers, ecologists and a wide range of specialists interested in the problems of soil cover conservation and environmental protection.

Slope Length Effects on Soil Loss for Steep Slopes

2000 ◽  
Vol 64 (5) ◽  
pp. 1759-1763 ◽  
Author(s):  
B. Y. Liu ◽  
M. A. Nearing ◽  
P. J. Shi ◽  
Z. W. Jia
Keyword(s):  
Soil Loss ◽  
Slope Length ◽  
Steep Slopes ◽  
Length Effects

scholarly journals Profile degradations of podzolic chernozem of the territory of Male Polissia

2017 ◽  
pp. 98-110
Author(s):  
Volodymyr Haskevych
Keyword(s):  
Physical Properties ◽  
Soil Layer ◽  
Vegetation Period ◽  
Soil Mass ◽  
Water Erosion ◽  
Soil Protection ◽  
Erosion Processes ◽  
Average Annual Loss ◽  
Study Results ◽  
Statistical Field

The article presents the results of the study of Male Polissia podzolic chernozems profile degradation. The causes and consequences of this dangerous natural and man-made phenomenon resulting in changes in the habitus of soils, losses of soil mass and humus, deterioration of general physical properties and structural and aggregate composition, decrease in soil fertility and agriculture unprofitability on the slopes have been analysed. In the study of the profile degradation of podzolic chernozems, the following methods have been used: comparative-geographical, comparative-profile, soil-catena, analytical, and statistical. Field studies were conducted after the vegetation period. According to the study results, the thickness of the profile of weakly eroded podzolic chernozems, in comparison with non-eroded types, decreased by 17.0–35.5% as compared to the standard, which corresponds to satisfactory and pre-crisis condition, in medium eroded soils - by 32.2–63.4%, the degree of degradation is estimated as pre-crisis, crisis and catastrophic. In the highly eroded types, the thickness of the soil layer decreased by 47.8–74.9%, which indicates a high and very high (crisis) level of profile degradation. Erosion soil loss compared to the standard in weakly eroded podzolic chernozems is 1245.0-3744.6 t/ha, in medium eroded soil – 6762.4-8321.0 t/ha, and in highly-eroded soil – 8874.0-11595.0 t/ha. It has been established that chernozems as a result of water erosion from one hectare of weakly eroded podzolic, on average 39.47–118.70 tons of humus was eroded, 214.36-237.98 tons was eroded from medium eroded ones, and 240.49-267.84 tons from highly eroded soils. The average annual loss of humus is from 0.23-0.68 t/ha in weakly eroded types to 1.37-1.53 t/ha in highly eroded podzolic chernozems. Erosion processes result in deterioration of physical properties of soils. The use of dense and low-humus plumage horizons for plowing causes compaction of soils and deterioration of structure. Minimization of podzolic chernozem profile degradation in Male Polissia is possible provided that the system of anti-erosion measures, especially the conservation of highly eroded soils, the introduction of soil protection methods for soil cultivation, optimization of the structure of crop areas, ban on cultivated crops on slopes more than 3° steep, consolidation of small areas in larger arrays are applied. It is also necessary to introduce a system of basic and crisis monitoring over the condition of eroded soils. Key words: Male Polissia, podzolic chernozems, profile degradation, water erosion, humus, soil conservation.

scholarly journals SOIL PROTECTION BY USED OF COVER CROPS CONSORTIA AND SINGLE CULTIVATION

2020 ◽  
Vol 5 (7) ◽  
Author(s):  
Daiana Jungbluth ◽  
Ana Regina Dahlem Ziech ◽  
Camila Roberta Pereira ◽  
Márcia Cristina Dos Santos ◽  
Patrick Machado
Keyword(s):  
Cover Crops ◽  
Soil Cover ◽  
Block Design ◽  
Single Species ◽  
Coverage Rate ◽  
Soil Protection ◽  
Rotation System ◽  
Randomized Block Design ◽  
Significant Difference ◽  
Technological University

The no-till system has been growing over the years and for this system to be successful, it is essential to maintain permanent vegetation cover over the soil, an adequate crop rotation system with minimal overturning. A strategy for soil protection is to introduce species of cover crops in winter under single or intercropping. The objective was to evaluate the rate of soil cover by intercropping between black oats (Avena strigosa L.) and forage turnip (Raphanus sativus L.) at different sowing densities, as well as the isolated species in terms of soil protection under no-tillage. The study was conducted at the Federal Technological University of Paraná (UTFPR), campus Santa Helena, with a randomized block design, with five treatments and three repetitions. The treatments were: 100% black oats (BO); 100% forage turnip (FT); 75% BO + 25% FT; 50% BO + 50% FT and 25% BO + 75% FT. The cover crops were sown in May 2019. The percentage of soil cover from 21 to 91 days after sowing (DAS) was evaluated using the photographic method, with weekly collection of images in an area delimited by a metallic frame (25 m²), positioned on the ground at two fixed points per plot. The coverage rate quantification was estimated by overlaying a grid with 100 points of intersection over each image. The rate of soil cover by consortia and single crops did not show a statistically significant difference. To 49 days, consortia had coverage equal to or greater than 70%, while for single species, this percentage was reached at 56 DAS and 70 DAS, for BO and FT, respectively. All treatments showed high potential for soil protection and coverage rate from 70 DAS.

WOOD CHIPS AS A SOIL COVER FOR CONSTRUCTION SITES WITH STEEP SLOPES

2002 ◽  
Vol 18 (6) ◽  
Author(s):  
J. R. Buchanan ◽  
D. C. Yoder ◽  
H. P. Denton ◽  
J. L. Smoot
Keyword(s):  
Soil Cover ◽  
Wood Chips ◽  
Construction Sites ◽  
Steep Slopes

scholarly journals Relationship Among Crop Systems, Soil Cover, and Water Erosion on a Typic Hapludox

2018 ◽  
Vol 42 (0) ◽  
Author(s):  
Pedro Luiz Terra Lima ◽  
Marx Leandro Naves Silva ◽  
John Norman Quinton ◽  
Pedro Velloso Gomes Batista ◽  
Bernardo Moreira Cândido ◽  
...  
Keyword(s):  
Soil Cover ◽  
Water Erosion

scholarly journals A Soil Erosion Indicator for Supporting Agricultural, Environmental and Climate Policies in the European Union

2020 ◽  
Vol 12 (9) ◽  
pp. 1365 ◽  
Author(s):  
Panos Panagos ◽  
Cristiano Ballabio ◽  
Jean Poesen ◽  
Emanuele Lugato ◽  
Simone Scarpa ◽  
...  
Keyword(s):  
European Union ◽  
Soil Erosion ◽  
Soil Conservation ◽  
Soil Loss ◽  
National Level ◽  
Water Erosion ◽  
Soil Protection ◽  
Conservation Practices ◽  
The European Union ◽  
The Eu

Soil erosion is one of the eight threats in the Soil Thematic Strategy, the main policy instrument dedicated to soil protection in the European Union (EU). During the last decade, soil erosion indicators have been included in monitoring the performance of the Common Agricultural Policy (CAP) and the progress towards the Sustainable Development Goals (SDGs). This study comes five years after the assessment of soil loss by water erosion in the EU [Environmental science & policy 54, 438–447 (2015)], where a soil erosion modelling baseline for 2010 was developed. Here, we present an update of the EU assessment of soil loss by water erosion for the year 2016. The estimated long-term average erosion rate decreased by 0.4% between 2010 and 2016. This small decrease of soil loss was due to a limited increase of applied soil conservation practices and land cover change observed at the EU level. The modelling results suggest that, currently, ca. 25% of the EU land has erosion rates higher than the recommended sustainable threshold (2 t ha−1 yr−1) and more than 6% of agricultural lands suffer from severe erosion (11 t ha−1 yr−1). The results suggest that a more incisive set of measures of soil conservation is needed to mitigate soil erosion across the EU. However, targeted measures are recommendable at regional and national level as soil erosion trends are diverse between countries which show heterogeneous application of conservation practices.

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