scholarly journals Application of USLE and GIS to predict erosion loss at Brantas Watershed

Author(s):  
Indarto Indarto

Erosion processes are still the dominant factor affecting land degradation. The rapid calculation of erosion loss is urgently required for conservation planning and management at the watershed level. This paper is reporting the use of USLE method and GIS at Brantas Watershed. The digital layer data of rainfall from 2005 to 2014, soil types, land use, and DEM (from ASTER GDEM2) were used as the main input. The research procedures consist of (1) data inventory dan preparation, (2) calculation of the erosion factors (R, K, LS, CP), and (3) calculation and classification of the erosion hazard. The erosivity factor (R) is calculated from the analysis of annual rainfall data. The erodibility factor (K) is obtained using analysis of soil type map. The length and slope factor (LS) is calculated from the DEM and Soil layer data. The crop cover and conservation activities (CP) is interpreted from RBI maps year 2014. The results showed that the erosion hazard in Brantas Watershed dominated by very low with predominantly the erosion yield of 0,96 ton/ha/year. Thus required conservation and watershed management activities to prevent an increase erosion hazard in the Brantas Watershed.Keywords: erosion yield, USLE, GIS, Brantas, Watershed

2021 ◽  
Vol 884 (1) ◽  
pp. 012010
Author(s):  
S. A Mulya ◽  
N. Khotimah

Abstract Prambanan District which located in Daerah Istimewa Yogyakarta Province has the potential for land degradation due to erosion processes. With the characteristics of annual rainfall more than 2000 mm / year, topography with a slope of more than 20% in upland areas, as well as the conversion of upland to dryland agriculture are factors that can trigger the erosion process more quickly. If the rate of erosion speed exceeds the ability of the soil to regenerate the soil body, its productivity will be disrupted and accelerate the formation of critical soil. Therefore, it is necessary to know the estimated rate of erosion, tolerable distribution of erosion, and the potential danger of erosion that occurs. The purpose of this study was to (1) predict the rate of erosion, (2) calculate the permissible erosion value, (3) identify the rate & index of erosion hazard. Data were collected using field surveys and soil sampling using stratified random sampling techniques with land units as the unit of analysis. The value of erosion was predicted using the Revised Universal Soil Loss Equation (RUSLE) method. The RUSLE method is described by the following equation, A=R*K*L*S*C*P, where; A as estimated averages annual loss of soil, R is the rainfall erosivity factor, K is the soil erodibility factor, LS is the slope length factor, C is the cover management factor, & P is the conservation practice factor. The results showed that the erosion value ranged from 0.39 - 268.55 tons/ha/year. Permissible erosion ranges from 8.4 – 15 tons/ha/year for Latosol and 27.4 ton/ha/year for Regosol. The Rate of Erosion Hazard is dominated by moderate erosion, covering an area of 1330.7 ha or 31.8% of the total area. The Erosion Hazard Index is dominated by the low class (<1.0) which is covered over 2703.1 ha or 64.61% of the total area.


2020 ◽  
Vol 3 (2) ◽  
pp. 32-38
Author(s):  
Prayogi Dhuha Brahmanto ◽  
Bambang Sulistyo ◽  
M. Faiz Barchia

Rindu Hati sub-watershed is located in District of Central Bengkulu, Bengkulu Province, that has flat until montainous topography with various slope and annual rainfall up to 4,032 mm year-1 which possible causes erosion. This research was aimed to analyze soil erosion at Rindu Hati sub-watershed based on the Universal Soil Loss Equation formula, using remote sensing imagery data and by applying GIS technique. USLE method were uses five parameters, those were length and slope factor, rainfall erosivity factor, crop management factor and land conservation , and soil erodibility factor. An overlay analysis has been conducted to obtain the erosion. Then, the result is overlaid with soil depth map to get the level of erosion hazard, which is classified into: very light, light, moderate, heavily, and very heavily. The results showed that the total erosion was 12,410,650.59 tons ha-1 year-1, while its level of erosion hazard were very light (15 tons ha-1 year-1) covering an area of 2,983 ha spreading over community agricultural areas and forest areas, the rate of light erosion (> 15-60 tons ha-1 year-1) has the largest area of covering an area of 10,410.05 ha which scattered in plantation areas having flat topography, moderate erosion rates (> 60-180 tons ha-1 year-1) of 1,317.33 ha spread over land areas with shrub land use and relatively flat topography, heavily erosion rates (> 180- 480 tons ha-1 year-1) covering 1,735.48 ha spread over land with shrub land use but has a hilly topography and very heavily erosion rates (> 480 tons ha-1 year-1) covering 2,700.42 ha located in the mining area. Erosion potential rate mapping will be very helpful in determining good and appropirate land management and conservation in the study area. 


2018 ◽  
Vol 13 (3) ◽  
pp. 505-512
Author(s):  
Hamzeh Noor ◽  
Mohammad Rostami Khalaj

Abstract Separating erosion data and assessing season-based models are of great importance considering the variation in soil erosion processes in different seasons, especially in semi-arid regions. However, evaluation of an erosion model using seasonal classification of data and at a micro-watershed level have rarely been considered. Therefore, the present study was conducted to evaluate the modified universal soil loss equation (MUSLE): 1) with the seasonal classification of data and 2) with the traditional approach (no classification of data), in the Sanganeh research micro-watershed. This watershed has an area of 1.2 ha and is located in the north east of Iran. The results showed that the original MUSLE overestimated the sediment yield in the study watershed. Also, after calibration of MUSLE, the seasonal classification of data (with a relative estimation error (RE) of 34%) showed its superior performance compared with the traditional calibration approach (with a RE of 62%). In this regard, the obtained REs of 33, 40, and 31% respectively for spring, autumn, and winter are within or close to the acceptable range.


2019 ◽  
Vol 12 (3) ◽  
pp. 859
Author(s):  
Joaquim Pedro de Santana Xavier ◽  
Alexandre Hugo Cezar Barros ◽  
Daniel Chaves Webber ◽  
Luciano José de Oliveira Accioly ◽  
Flávio Adriano Marques ◽  
...  

Dentre os diversos métodos indiretos para estimar as perdas de solo por erosão, a Equação Universal de Perdas de Solo (EUPS) é a mais utilizada devido a sua robustez e por ser constituída de uma simples estrutura fatorial, que integra fatores naturais e antrópicos atuantes na perda de solos. A erosão é um dos fenômenos mais danosos ao solo e às atividades humanas e por isso seu estudo é importante. Para o cálculo das perdas de solo por meio da EUPS, a avaliação da erosividade das chuvas (fator R) é essencial, pois estima o fenômeno produzido pelas chuvas. O objetivo deste trabalho foi avaliar três metodologias disponíveis de obtenção da erosividade das chuvas para a região do semiárido pernambucano, avaliando sua influência nos resultados da EUPS. Os três modelos selecionados para estimar o Fator R foram desenvolvidos por Wischmeier e Smith (mais conhecido e utilizado), por Silva que estimou valores para diversas regiões do País e por Cantalice e outros que trabalharam especificamente para cada região climática do estado de Pernambuco. Os resultados indicam que as metodologias de Wischmeier e Smith e Silva obtiveram resultados de erosividade da chuva semelhantes, tendo Silva alcançado valores maiores. Cantalice e outros obtiveram os resultados mais baixos. Os resultados da EUPS indicam que, quantitativamente, os diferentes fatores R geram grande diferença nas perdas de solo, porém, qualitativamente chegam a resultados semelhantes na classificação de áreas de maior erosão, de acordo com a FAO. Logo, as três metodologias são viáveis na identificação de áreas prioritárias para a mitigação da erosão.   A B S T R A C TAmong several indirect methods to estimate soil erosion loss, the Universal Soil Loss Equation (EUPS) is the most used due to its robustness and because it is constituted of a simple factorial structure that integrates natural and anthropic factors which act in the loss of soils. Erosion is one of the most damaging phenomena to the soil and the human activities, evidencing the importance of studying it. The evaluation of rainfall erosivity (R factor) is essential for the calculation of soil loss through the EUPS, since it is possible to estimate how significant rainfall is to the occurrence of this phenomenon. The objective of this work was to evaluate three methodologies to obtain the rainfall erosivity available for the semi - arid region of Pernambuco, evaluating its influence on the results of the EUPS. The three models used to estimate the R-factor were developed by Wischmeier and Smith, the best known and used model, Silva who estimated values for several regions of the country and Cantalice and others who worked specifically for each climatic region of the state of Pernambuco. As a result, very similar results of rainfall erosivity were obtained between Wischmeier and Smith´s and Silva´s methodology, with Silva reaching higher values of energy amplitude, while Cantalice and others obtained the lowest results. The results of EUPS indicate that, quantitatively, the different R factors generate a large difference in soil loss, but qualitatively they reach similar results in the classification of areas where erosion are greater, according to the FAO. Therefore, the three methodologies are feasible in the identification of priority areas for erosion mitigation.Keywords: soil, rainfall erosivity, USLE, GIS


2019 ◽  
Vol 53 ◽  
pp. 85-96
Author(s):  
Volodymyr Haskevych ◽  
Nadiya Lemeha ◽  
Anastasiya Vishchur

The results of the research of degradation of dark gray podzolized soils (Luvis Greyzemic Phaeozems) of the Chyzhykiv ridge are presented. The causes and consequences of this dangerous natural and anthropogenic phenomenon are analyzed. It has been established that the intensive agricultural use of soils caused the activation of water erosion processes, the development of physical degradation processes, which lead to soil compaction, deterioration of their general physical properties, and loss of humus. Degradation processes lead to a decrease in soil fertility and unprofitability of agriculture, worsen the ecological state of the environment. In the study of degradation processes and their consequences in dark gray podzolized soils, the following methods were used: comparative-geographical, comparative-profile, catena method, analytical, statistical. Soil field explorations were carried out after the growing season. The most dangerous among the degradation processes are erosion degradation, which leads to a decrease in the capacity of the soil profile and deterioration of the soil agrophysical properties. The results of the studies demonstrated that the capacity of the profile of poorly eroded soils decreased on average by 14.5 cm compared to the standard, in medium-eroded – by 28.3 cm, in highly-eroded – by 50.8 cm. Soils underwent erosion from low to very high (crisis) degree. Degradation processes of anthropogenic genesis caused a deterioration of the structural and aggregate state of the soils, which is manifested in a decrease in the content of agronomically valuable soil aggregates and the dominance of the sloping fraction. According to the research results, the content of agronomically valuable aggregates with a size of 10–0.25 mm in the arable soil layer is 18.65–33.86 %, which indicates a high and very high (crisis) level of degradation. Soils also undergo degradation due to re-compaction, which is manifested in an increase in the density of the structure and a decrease in the overall porosity of the soil. Long anthropogenic pressure on soils and erosion degradation processes have led to a decrease in humus content. In particular, in poorly eroded soils the humus content is 2.03 %, in medium-eroded soils – 1.45 %, in highly eroded – 1.06 %, which is 16.9–64.6 % less than the standard. Measures are proposed to minimize the degradation of the dark gray podzolized soils of the Chyzhykiv ridge, which consist in the application of anti-erosion measures and soil-protective methods of soil processing, conservation of heavily degraded lands. The introduction of basic and crisis monitoring of the state of soils in the research area is recommended. Key words: the Chyzhykiv ridge, dark gray podzolized soils, erosion, degradation, soil protection.


2020 ◽  
Vol 28 (1) ◽  
pp. 65-74
Author(s):  
Andrey N. Timofeev

The article gives a brief description of the Voronezh region, provides data on the cause of landslides in its territory. The cyclical nature of landslide processes is noted, which in the region is on average 6-8 years. Attention is focused on anthropogenic activity, leading to the occurrence of creeping layers of the earth. The main causes of erosion processes are: significant plowing of the area (80%), which is not subject to the rules of anti-erosion agrotechnology; the irrational use of pastures and hayfields; an extensive gully-beam network. The role of temporary reservoirs formed in the ruts of unpaved roads, passing along the slopes and ravines, as a source of overmoistening of the soil layers and initiation of landslide processes is considered. The analysis of the landslide distribution over the territory of the Voronezh region and their dependence on the network of dirt roads is given. The areas of the Voronezh region were ranked by the number of landslide processes associated with the impact of a number of unpaved highways. Of the 32 districts of the region, according to this ranking, 12 are extremely dangerous, very dangerous and dangerous, and the same areas have a very extensive network of unpaved roads running near ravines, steep banks of rivers and ponds, where potentially flow of landslide processes. Dirt roads often have relatively deep ruts where melted or rainwater accumulates, forming local micro-ponds. Flowing to the waterproof layer, water saturates the soil layer, which can slide down the slope, forming a landslide process. It is necessary to predict the possibility of the occurrence of dangerous natural phenomena when laying automobile dirt roads.


Author(s):  
Volodymyr Haskevych

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.


Author(s):  
Myroslav Voloshchuk

Based on generalization of literary sources, normative legal, stock materials and experimental data, the complex situation of soil degradation is highlighted. Different types and intensity of the manifestation of soil degradation, their distribution and characteristics are described. The threatening situation of manifestation of degradation processes in some regions of Ukraine is shown, among which soil erosion occupies the leading place. More than 4.5 million hectares are occupied by medium and strongly ground soils, including 68 thousand hectares completely lost their humus horizon. Particularly large areas of eroded soils are distributed on arable land in the Vinnytsia, Luhansk, Donetsk, Odesa, Chernivtsi and Ternopil regions, where the average annual ground wash is 24.5–27.8 t/ha with a tolerance of 2.5–3.7 t/ha. As a result of erosion processes from the total area of agricultural land, about 500 million tons of fertile soil layer is washed out on average annually, which contains about 24 million tons of humus, 0.96 million tons of nitrogen, 0.68 million tons of phosphorus and 9.4 million tons of potassium equivalent to 320–333 million tons of organic fertilizers, and ecological and economic losses due to erosion exceed 9 billion UAH. Flat soil was associated with linear erosion. The main indicators characterizing the degree of damage to land by linear erosion are the density of ravines, the distance and area between them, the slope, the properties of soils and rocks, the morphometric parameters of the ravines and their catchment areas. According to various estimates, the area of land affected by linear erosion in the country increases by 5–10 thousand ha annually. The effect of the ravines on the complete destruction of the land, deformation of the soil cover is highlighted. Information on various types of soil pollution by poison chemicals, industrial waste is given. According to the prediction of scientists in such a situation, 120–150 years on the planet can destroy the fertile soil layer. Key words: erosion, dehumidification, pollution, waterlogging, acidity, degraded land.


Author(s):  
Tamara Vieira Pascoto ◽  
Simone Andrea Furegatti ◽  
Anna Silvia Palcheco Peixoto

There are several factors that directly or indirectly influence erosion processes. In order to properly understand the behavior of these processes, some factors need to be analyzed together. Determining them wrongly can compromise the study resulting in wrong actions. For this reason, methodologies are always sought to measure them quantitatively and qualitatively in the most accurate possible way. Land use is one of the main factors liable to inaccuracies in its determination. To use this parameter in mapping erosive processes, researchers need to delimit it, classify it, and measure it. In order to better understand the complexity of considering this parameter, the present study analyzed an erosive feature that, although stabilized, has a component in constant development. Initially, a visual analysis indicated the same classification of land use for both conditions, despite having different behaviors, leading to the need for a detailed analysis. Such analysis comprised a historical survey through aerial photos and interviews with residents and employees of the city hall about the evolution of the feature from 2008 to 2019. It also included the analysis of other influencing factors that could be responsible for this difference in behavior in the area. Two different traces of the contribution areas of the gully and branch were also considered. One considering only aerial images, and the other considering the knowledge acquired during the research about the evolution of the feature. It was concluded, then, that an analysis of the use-only occupation factor based on aerial images can accentuate the inaccuracy of the measurement of this factor.


2019 ◽  
Vol 7 (2) ◽  
pp. 393-410 ◽  
Author(s):  
Renee van Dongen ◽  
Dirk Scherler ◽  
Hella Wittmann ◽  
Friedhelm von Blanckenburg

Abstract. Concentrations of in-situ-produced cosmogenic 10Be in river sediment are widely used to estimate catchment-average denudation rates. Typically, the 10Be concentrations are measured in the sand fraction of river sediment. However, the grain size of bedload sediment in most bedrock rivers covers a much wider range. Where 10Be concentrations depend on grain size, denudation rate estimates based on the sand fraction alone are potentially biased. To date, knowledge about catchment attributes that may induce grain-size-dependent 10Be concentrations is incomplete or has only been investigated in modelling studies. Here we present an empirical study on the occurrence of grain-size-dependent 10Be concentrations and the potential controls of hillslope angle, precipitation, lithology, and abrasion. We first conducted a study focusing on the sole effect of precipitation in four granitic catchments located on a climate gradient in the Chilean Coastal Cordillera. We found that observed grain size dependencies of 10Be concentrations in the most-arid and most-humid catchments could be explained by the effect of precipitation on both the scouring depth of erosion processes and the depth of the mixed soil layer. Analysis of a global dataset of published 10Be concentrations in different grain sizes (n=73 catchments) – comprising catchments with contrasting hillslope angles, climate, lithology, and catchment size – revealed a similar pattern. Lower 10Be concentrations in coarse grains (defined as “negative grain size dependency”) emerge frequently in catchments which likely have thin soil and where deep-seated erosion processes (e.g. landslides) excavate grains over a larger depth interval. These catchments include steep (> 25∘) and humid catchments (> 2000 mm yr−1). Furthermore, we found that an additional cause of negative grain size dependencies may emerge in large catchments with weak lithologies and long sediment travel distances (> 2300–7000 m, depending on lithology) where abrasion may lead to a grain size distribution that is not representative for the entire catchment. The results of this study can be used to evaluate whether catchment-average denudation rates are likely to be biased in particular catchments.


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