Detachment Of Soil Particles Research Articles

Impact of Forest Roads on Hydrological Processes

The current review summarizes the knowledge generated by the recently published studies of the last twenty years, in the field of forest road networks, concerning the impact of forest road construction on hydrological processes. The currently applied methodology techniques/practices are discussed, the findings are highlighted and effective mitigation measures to mitigate the impact of forest roads are proposed. Critical for the minimization of the impact of forest roads on overland flow is the significant decrease in road surface runoff and overland flow velocity. The decrease in runoff energy reduces the detachment of soil particles and transportation in streams. The disturbances of forest roads in logging areas should be limited to decrease soil erosion. Additionally, aiming to minimize sediment transportation into the streams, it is very important to reduce the connectivity between the forest roads (or skid trails) and streams. The positive role of vegetation and organic matter on the road prism, naturally/technically established riparian buffers along the streams, and the use of appropriate bioengineering designs for each area significantly decrease the runoff generation and sedimentation. From a construction point of view, the decrease in short and long-term forest road-related impact could be achieved by reducing the depth of excavations and the use of soil compaction limiting technology during forest works. The road network design should be more efficient, avoiding hydrologically active zero-order basins. Techniques that minimize the length and connectivity among skid trails, unpaved roads and streams are highly crucial. Broad-based dips, immediate revegetation and outsloping of the road base are considered good road construction practices. Research should be focused on the hydrologic behavior of forest road networks and on the impact at the watershed scale, the degree of connectivity, utilizing plenty of qualitative field data, especially during intense rainfall events, which has been proven to exacerbate the runoff and sediment generation and transportation into the stream networks.

Delineation of vulnerable areas to water erosion in a mountain region using SDR-InVEST model: A case study of the Ourika watershed, Morocco

The Ourika watershed is characterized by higher than average flood flows, a rugged topography, a sparse vegetation cover and a friable substrate that makes it vulnerable to soil erosion. Soil is an important non-renewable asset capital, providing several ecosystem services that sustain life through physical and biological regulation processes. The loss, or otherwise, redistribution of biota by soil erosion in the Ourika watershed has received little attention and thus constitutes a key knowledge gap that needs to be addressed. This study quantifies the level of erosion and maps its spatial distribution in the watershed using the Sediment Delivery Ratio (SDR) of the Integrated Valuation of Ecosystem Services and Trade-offs model (InVEST 3.6.0). The SDR maps the overland sediment generation and delivery to the stream at the watershed level using rainfall, soil properties, topography, cover management and cropping practices as predefined set of input variables. Recommended internal model calibration was used and results were compared to similar studies carried out in different parts of Morocco for validation. The results reveal that 93% of the watershed is subject to a strong rainfall aggressiveness greater than 50 MJ mm ha–1 h–1 yr–1 under an average rainfall intensity of 541 mm/year, rainfall capacity to initiate the detachment and transport of soil particles by runoff, and only 11.5 % of the watershed area is protected with vegetative cover. We find that overall, the Ourika watershed is losing its soil to erosion at an alarming average rate of 258.48 ton.ha–1.yr–1, a rate well above the tolerable threshold of 7 ton.ha–1.yr–1. The spatial distribution of this loss shows areas that need to be urgently remedied. The primary factors for soil erosion in the Ourika watershed appear to be related to the aggressive nature of local rainfall and the inherent susceptibility of soils, which can be costly to this cash-crop region. Because rainfall intensity, soil properties, and topography are intrinsic characteristics of the watershed, we suggest that seasonally adapted cropping rotations that maintains conservative practices with a high cover management may reduce soil erosion in the Ourika watershed.

Theoretical expressions for soil particle detachment rate due to saltation bombardment in wind erosion

Theoretical expressions for soil particle detachment rate due to saltation bombardment in wind erosion

Prediction of soil loss due to erosion using support vector machine model

Soil erosion refers to the detachment and removal of soil particles from land (topsoil), by the natural physical forces (water, glacier and wind). Soil erosion causes soil loss in the catchment or any land areas severely impacting agriculture activity, sedimentation in the dam reservoirs, and hampering developmental activities. Therefore, it is desirable to accurately measure soil loss due to erosion for the development and management of an area. With this objective, a well-known machine learning algorithm Support Vector Machine (SVM) has been used in the development of the soil loss prediction model. Eight erosion affecting variable inputs: ambient temperature Tair, rainfall, Antecedent Moisture Conditions (AMC), rainfall intensity, slope, vegetation cover, soil temperature Tsoil and moisture of the soil. Data on published literature was used in the model study. The accuracy of the proposed SVM was assessed by using three statistical performance evaluation indicators namely Person correlation coefficient (R), Root Mean Squared Error (RMSE), Mean Squared Error (MAE). Partial Dependence Plots (PDP) was used to investigate the dependence of prediction results of eight input variables used in the model study. Model validation results showed that SVM model performed well for the prediction of soil loss for testing (R = 0.8993) and also for training (R=0.9123). Rainfall intensity and vegetation cover were found to be the two most important affecting input parameters for the soil loss prediction.

Impact of Disdrometer Types on Rainfall Erosivity Estimation

Soil erosion by water is affected by the rainfall erosivity, which controls the initial detachment and mobilization of soil particles. Rainfall erosivity is expressed through the rainfall intensity (I) and the rainfall kinetic energy (KE). KE–I relationships are an important tool for rainfall erosivity estimation, when direct measurement of KE is not possible. However, the rainfall erosivity estimation varies depending on the chosen KE–I relationship, as the development of KE–I relationships is affected by the measurement method, geographical rainfall patterns and data handling. This study investigated how the development of KE–I relationships and rainfall erosivity estimation is affected by the use of different disdrometer types. Rainfall data were collected in 1-min intervals from six optical disdrometers at three measurement sites in Austria, one site in Czech Republic and one site in New Zealand. The disdrometers included two disdrometers of each of the following types: the PWS100 Present Weather Sensor from Campbell Scientific, the Laser Precipitation Monitor from Thies Clima and the first generation Parsivel from OTT Hydromet. The fit of KE–I relationships from the literature varied among disdrometers and sites. Drop size and velocity distributions and developed KE–I relationships were device-specific and showed similarities for disdrometers of the same type across measurement sites. This hindered direct comparison of results from different types of disdrometers, even when placed at the same site. Thus, to discern spatial differences in rainfall characteristics the same type of measurement instrument should be used.

Detachment of dilatant soil due to high hydraulic shear stresses explained

When soil surfaces are exposed to high shear stresses induced by high-velocity water flows, they erode. Erosion consists of the detachment, entrainment and transport of soil particles. When exposed to high shear stresses the process of soil detachment is no longer given by the pick-up of individual particles but by the continuous shear failure of layers of soil. The understanding of how soil properties influence the detachment rate of soil is lacking. This paper presents how the bed shear stress, initial and critical porosity, hydraulic conductivity, and density influence the detachment rate of dilatant soils which are subjected to high-velocity flows. Based on the constitutive mass and momentum balance equations it is hypothesized that the exchange of mass and momentum during soil detachment corresponds with that situation for which the dilatancy induced shear resistance of the soil is maximum. The hypothesis is validated against high-velocity erosion experiments on sand.

The change of rainfall kinetic energy content with altitude

Erosion is the process of land degradation due to rainfall and other environmental factors, and it can be described by indices such as the kinetic energy of rainfall (KE). Microphysical data from disdrometers have been used to determine the relationship between kinetic energy content (KEmm, in J m−2 mm−1) and rainfall intensity (R, in mm h−1). Optical disdrometer (PWS100) measurements were gathered between 2014 and 2018 at five sampling sites across Mexico, and the data analyzed to study the characteristics of KEmm–R relationships with altitude. A PWS100 unit at each of the sampling sites was collocated a few meters from a tipping-bucket rain gauge to record R simultaneously. Individual raindrops fall speeds measured with the disdrometers were found to agree well with theoretical estimations using the environmental conditions at each sampling site. The mean fall velocities indicated that raindrops detected at the continental sampling sites (medium and high altitudes) have greater speeds than those near coastal areas (low altitudes). Comparisons of the estimated KEmm for rainy periods with comparable R show greater values as the altitude increases. This result is attributed to the increase of raindrop fall speed due to the air density decrement with altitude. Exponential relations between KEmm and R based on one-minute sampling periods were fitted for each sampling site, producing high values of coefficients of determination and suggesting a good response. Finally, the maximum kinetic energy parameter, KEmax, in the empirical KEmm–R equations was found to increase with altitude. These findings indicate that the detachment of soil particles by individual drops are magnified at higher altitude locations.

Impact of near‐surface hydraulic gradient on the interrill erosion process

AbstractThe impact of near‐surface hydraulic gradients on interrill erosion is still obscure. The objective of this study is to distinguish the dominant interrill erosion process in areas impacted by near‐surface hydraulic gradients. A series of rainfall simulations were conducted on a clay loam soil subjected to near‐surface hydraulic gradients that shifted from drainage/saturation conditions to seepage conditions under three rainfall intensities (30, 60 and 90 mm hr−1) and two slope gradients (5° and 10°). The results showed significant differences in soil loss between all the treatments. The sediment concentrations for seepage conditions were 0.57 to 7.02 times greater than those for drainage conditions. The correlation analysis indicated that the near‐surface hydraulic gradient was a governing factor affecting interrill erosion. The critical flow rate was larger than 90 mm hr−1, suggesting that thin sheet flow does not have sufficient power to detach soil particles without raindrop impact. Furthermore, the detachment rates by raindrop impact were 1.12 to 4.60 times greater for seepage conditions than for drainage conditions. As the near‐surface hydraulic gradient shifted from drainage conditions to seepage conditions, it transitioned from transport‐limited to detachment‐limited, and the contribution of interrill erosion to overall erosion increased from 20.19 to 75.30%. The critical point of dominant interrill erosion process transition existed between saturation (SA) and artesian seepage in 20 cm of hydrostatic pressure head (SP20). The results emphasize the importance of the near‐surface hydraulic gradients’ impact on the interrill erosion process. Further investigations need to be verified in different soil types, steeper slopes and natural storms.Highlights The impact of near‐surface hydraulic gradients on interrill erosion is only partially understood. Dominant interrill erosion processes are identified under near‐surface hydraulic gradients. The critical point of dominant interrill erosion process transition exists between SA and SP20. The dominant erosion process varied as a function of near‐surface hydraulic gradients.

Experimental Setup for Splash Erosion Monitoring—Study of Silty Loam Splash Characteristics

An experimental laboratory setup was developed and evaluated in order to investigate detachment of soil particles by raindrop splash impact. The soil under investigation was a silty loam Cambisol, which is typical for agricultural fields in Central Europe. The setup consisted of a rainfall simulator and soil samples packed into splash cups (a plastic cylinder with a surface area of 78.5 cm2) positioned in the center of sediment collectors with an outer diameter of 45 cm. A laboratory rainfall simulator was used to simulate rainfall with a prescribed intensity and kinetic energy. Photographs of the soil’s surface before and after the experiments were taken to create digital models of relief and to calculate changes in surface roughness and the rate of soil compaction. The corresponding amount of splashed soil ranged between 10 and 1500 g m−2 h−1. We observed a linear relationship between the rainfall kinetic energy and the amount of the detached soil particles. The threshold kinetic energy necessary to initiate the detachment process was 354 J m−2 h−1. No significant relationship between rainfall kinetic energy and splashed sediment particle-size distribution was observed. The splash erosion process exhibited high variability within each repetition, suggesting a sensitivity of the process to the actual soil surface microtopography.

Deforestation Due to Artisanal and Small-Scale Gold Mining Exacerbates Soil and Mercury Mobilization in Madre de Dios, Peru.

Artisanal and small-scale gold mining (ASGM) is a significant contributor of mercury (Hg) contamination and deforestation across the globe. In the Colorado River watershed in Madre de Dios, Peru, mining and deforestation have increased exponentially since the 1980s, resulting in major socioeconomic shifts in the region and two national state of emergency (2016 and 2019) in response to concerns for wide-scale mercury poisoning by these activities. This research employed a watershed-scale soil particle detachment model and environmental field sampling to estimate the role of land cover change and soil erosion on river transport of Hg in a heavily ASGM-impacted watershed. The model estimated that observed decreases in forest cover increased soil mobilization by a factor of two in the Colorado River watershed during the 18 year period and by 4-fold in the Puquiri subwatershed (the area of most concentrated ASGM activity). If deforestation continues to increase at its current exponential rate through 2030, the annual mobilization of soil and Hg may increase by an additional 20-25% relative to 2014 levels. While, the estimated total mass of Hg transported by rivers is substantially less than the estimated tons of Hg used with ASGM in Peru, this research shows that deforestation associated with ASGM is an additional mechanism for mobilizing naturally occurring and anthropogenic Hg from terrestrial landscapes to aquatic environments in the region, potentially leading to bioaccumulation in fish and exposure to communities downstream.

Numerical modelling of internal erosion during hydrate dissociation based on multiphase mixture theory

SummaryIt has been reported that sand production, which is a simultaneous production of soil particles along with gas and water into a production well, forced to terminate the operation during the world's first offshore methane production test from hydrate‐bearing sediments in the Eastern Nankai Tough. The sand production is induced by internal erosion, which is the detachment and migration of soil particles from soil skeleton due to seepage flow. The inflow of the eroded soil particles into the production well leads to damage of the production devices. In the present study, a numerical model to predict the chemo‐thermo‐mechanically coupled behavior including internal erosion during hydrate dissociation has been formulated based on the multiphase mixture theory. In the proposed model, the internal erosion is expressed as mass transition of soil particles from soil skeleton to the fluidized soil particles. Since the internal erosion is considered to depend on the soil particle size, mass of soil particles are divided into several groups that have different representative particle diameters, and the constitutive equations for the onset condition and the mass transition rate of the internal erosion are formulated for each group. Also, transportation of soil particles in the liquid phase is formulated for each particle size group in the proposed model. Finally, a simulation of the methane gas production from the hydrate‐bearing sediment by depressurization method is presented, and the internal erosion and the dissociation behavior are discussed.

Dye-tracer technique for rill flows by velocity profile measurements

Water flow on hillslope soil surface supplies energy which is required to detach soil particles, to transport and deposit sediments, therefore flow velocity is a key variable related to hillslope hydrodinamics of soil erosion processes. Among the different methods available for measuring velocity of shallow interrill and rill flow, the trace technique is widely used. Trace technique is applied by adding a material (salt, magnetic material, water isotope, floating object) and then measuring the speed of the material to travel a known distance from the injection point.When flow velocity is measured using a dye-tracing method, the mean velocity is calculated by multiplying the measured surface velocity of the leading edge of the tracer plume by a correction factor which was generally empirically deduced. The main uncertainty of the dye-tracing technique stands in the estimate of this correction factor, which is the ratio between the mean flow velocity and the surface velocity. The main goal of this paper is establishing a theoretical relationship for calculating the correction factor by using a power velocity profile. At first, the developed analysis demonstrated that the correction factor only depends on the exponent of the power velocity distribution (Eq. (5)). Then, this theoretical expression of the correction factor was applied using the velocity profiles measured by Baiamonte and Ferro for the condition of sediment-free flow in motion on a rough bed and by Coleman for a sediment-laden flow moving on a smooth flume.Using the correction factor values calculated by the velocity measurements carried out for the sediment-free flow in motion on a rough bed, the relationship between the correction factor and roughness height was established. In agreement with a previous study by Ali et al., for a sediment-free flow the correction factor increases with roughness height.Finally, the velocity profile measurements carried out for a sediment-laden flow in motion on a smooth bed were used to state the effect of sediment load on the correction factor. This last analysis allowed to conclude, in agreement with Li and Abrahams and Zhang et al., that the correction factor decreases when the sediment load increases.

Assessment of Rainfall Kinetic-Energy–Intensity Relationships

Raindrop-impact-induced erosion starts when detachment of soil particles from the surface results from an expenditure of raindrop energy. Hence, rain kinetic energy is a widely used indicator of the potential ability of rain to detach soil. Although it is widely recognized that knowledge of rain kinetic energy plays a fundamental role in soil erosion studies, its direct evaluation is not straightforward. Commonly, this issue is overcome through indirect estimation using another widely measured hydrological variable, namely, rainfall intensity. However, it has been challenging to establish the best expression to relate kinetic energy to rainfall intensity. In this study, first, kinetic energy values were determined from measurements of an optical disdrometer. Measured kinetic energy values were then used to assess the applicability of the rainfall intensity relationship proposed for central Italy and those used in the major equations employed to estimate the mean annual soil loss, that is, the Universal Soil Loss Equation (USLE) and its two revised versions (RUSLE and RUSLE2). Then, a new theoretical relationship was developed and its performance was compared with equations found in the literature.

Field-based determination of controls on runoff and fine sediment generation from lowland grazing livestock fields

Compared with arable land, there is a paucity of field-based measurements of erosion rates and controls for lowland temperate grassland supporting ruminant agriculture. Despite this evidence gap, reducing diffuse fine sediment pollution from intensively farmed grassland has been recognised as essential for improving compliance with water quality targets. Improved information on erosion rates and controls within intensively managed lowland grazing livestock systems are prerequisites for informing best management practices for soil and water resource conservation.Accordingly, this study assembled such information using the North Wyke farm platform in south west England where flow, suspended sediment concentration, rainfall and soil moisture are monitored quasi-continuously in 15 hydrologically-isolated (1.54–11.12 ha) catchments. This region of the UK is representative of temperate lowland ruminant grazing landscapes with semi permeable soil drainage.Catchment area was the major control on both water and sediment flux. When normalised to catchment area, sediment yields were controlled by the erodibility of the catchment's soils. Ploughing for re-seeding of grass swards was the major factor that affected this. Whilst total rainfall had a small effect on sediment yields, slope and the damage of soils by livestock had no significant effects. This finding may be due to the overriding effects of ploughing and re-seeding of some fields during the study period.Detachment by impacting raindrops mobilised sediment particles across the entire field with diffuse saturation-excess overland flow responsible for their transport. The majority of erosion occurred during the rising limbs of storm events when there is an abundance of easily detached soil particles. Given that erosion and sediment transport are driven mechanistically by processes affecting the entire field areas, a reduction in sediment yield through the implementation of highly spatially-targeted in-field management such as that for feeder ring use, troughs, poached tracks or gateways would likely be very challenging. Instead, stocking density and grazing regime management, as well as carefully planned ploughing and re-seeding will be more beneficial for erosion control.

Evaluation of Effect of Different Crop Types On Soil Water Erosion: Case Study of the Myjava Hill Land, Slovakia

The main objective of the study is to model and evaluate the effect of different types of crops on soil water erosion by using the physically-based EROSION-3D model. The EROSION-3D model is based on physical principles and simulates surface runoff, erosion, the deposition of material, and the detachment of soil particles for a single rainfall event. The erosion model was applied to a small catchment of Svacenicky Creek (6.86 km2), which is situated in the Myjava Hill Land in the western part of Slovakia; it is known for its quick runoff responses and related erosion processes. The parts most prone to erosion processes are located in the northern part of the Svacenicky Creek catchment on slopes with a more than 20% angle. Three crop types (winter wheat, silage corn and sugar beets) were chosen in consideration of their growing periods in order to assess the dynamic character of the erosion processes, especially during the growing period of each single crop. The modelling was performed for design rainfall events that were derived separately for each month and which were inputs to the model according to the growing period of the selected crops; six scenarios of the initial soil moisture in a range of 10-40% were designed. The results demonstrated the differences between the erosive effects of the crops selected during their growing periods. Finally, the results were statistically evaluated to determine the differences between the various scenarios of the initial moisture, different rainfall events, and selected crop types.

Effect of clogging of stone column on drainage capacity during soil liquefaction

Stone columns act as vertical drains, and due to their high permeability, allow for the quick dissipation of earthquake induced excess pore water pressure. When water flows through a loose sandy soil, it washes away fine soil particles. The fine sand particles get detached when the hydrodynamic force applied on the soil particles breaks the inter particle bonds between soil grains. These detached soil particles are then migrated by the seepage water. Based on the concentration of the soil particles in the seepage water, these may be captured at the pore constriction of gravels during the flow of water through the stone column. Thus, the clogging of stone column initiates which reduces of the permeability of column. The rate of dissipation of pore water pressure during earthquake is affected due to the clogging of column. In this paper, a mathematical model is proposed to determine the rate of dissipation of pore water pressure of stone column-reinforced ground by considering the clogging effect of column. The result obtained from the proposed model is verified with the available in-situ experimental data. A parametric study is also performed to investigate the effect of different parameters of the proposed model on the clogging of stone column. It is observed that when the permeability ratio, compressibility ratio and area ratio decrease, the possibility of clogging increases. The peak value of the excess pore water pressure ratio can increase up to around 50% due to clogging.

Rainfall induced erosion of soils used in earth roads

Earth roads in rural areas of the developing world are key engines to the development of countries. They give access to education and health services, sustain agriculture and businesses, and promote social interactions between communities. However, earth roads suffer substantially from poor engineering and funding for construction and maintenance. Rainfall is probably their most dangerous enemy resulting in soil particle detachment leading to the loss of surface material. A laboratory rainfall simulator was used to identify the performance of an earth road surface compacted at the maximum dry density against rainfall energy and surface flow. Under the rain intensity of 30mm/hr, erosion increased with rain duration from 0 to 30 minutes. Fine sand (0.06 – 0.02mm) and medium sand (0.02 – 0.6mm) particles eroded faster than coarse sand (0.6 – 2mm) and gravel (> 2mm) particles of the sediments collected at 5 minutes intervals of time. Additionally, a 20cm x 20cm photograph at the same place was analysed using ImageJ software and showed reduction in number of particles from 18554 at 10 min to 5803 at 25 min as smaller particles had eroded in the meantime.

Effects of rainfall patterns on runoff and rainfall-induced erosion

Rainfall-induced erosion involves the detachment of soil particles by raindrop impact and their transport by the combined action of the shallow surface runoff and raindrop impact. Although temporal variation in rainfall intensity (pattern) during natural rainstorms is a common phenomenon, the available information is inadequate to understand its effects on runoff and rainfall-induced erosion processes. To address this issue, four simulated rainfall patterns (constant, increasing, decreasing, and increasing - decreasing) with the same total kinetic energy were designed. Two soil types (sandy and sandy loam) were subjected to simulated rainfall using 15 cm × 30 cm long detachment trays under infiltration conditions. For each simulation, runoff and sediment concentration were sampled at regular intervals. No obvious difference was observed in runoff across the two soil types, but there were significant differences in soil losses among the different rainfall patterns and stages. For varying-intensity rainfall patterns, the dominant sediment transport mechanism was not only influenced by raindrop detachment but also was affected by raindrop-induced shallow flow transport. Moreover, the efficiency of equations that predict the interrill erosion rate increased when the integrated raindrop impact and surface runoff rate were applied. Although the processes of interrill erosion are complex, the findings in this study may provide useful insight for developing models that predict the effects of rainfall pattern on runoff and erosion.

Uncertainties in rainfall kinetic energy-intensity relations for soil erosion modelling

For bare soil conditions, the most important process driving and initiating splash and interrill erosion is the detachment of soil particles via raindrop impact. The kinetic energy of a rainfall event is controlled by the drop size and fall velocity distribution, which is often directly or indirectly implemented in erosion models. Therefore, numerous theoretical functions have been developed for the estimation of rainfall kinetic energy from available rainfall intensity measurements. The aim of this study is to assess differences inherent in a wide number of kinetic energy-rainfall intensity (KE-I) relations and their role in soil erosion modelling. Therefore, 32 KE-I relations are compared against measured rainfall energies based on optical distrometer measurements carried out at five stations of two substantially different rainfall regimes. These allow for continuous high-resolution (1-min) direct measurements of rainfall kinetic energies from a detailed spectrum of measured drop sizes and corresponding fall velocities. To quantify the effect of different KE-I relations on sediment delivery, we apply the erosion model WATEM/SEDEM in an experimental setup to four catchments of NE-Germany. The distrometer data shows substantial differences between measured and theoretical models of drop size and fall velocity distributions. For low intensities the number of small drops is overestimated by the Marshall and Palmer (1948; MP) drop size distribution, while for high intensities the proportion of large drops is overestimated by the MP distribution. The distrometer measurements show a considerable proportion of large drops falling at slower velocities than predicted by the Gunn and Kinzer (1949) terminal velocity model. For almost all rainfall events at all stations, the KE-I relations predicted higher cumulative kinetic energy sums compared to the direct measurements of the optical distrometers. The different KE-I relations show individual characteristics over the course of rainfall intensity levels. Our results indicate a high sensitivity (up to a range from 10 to 27 t ha−1) of the simulated sediment delivery related to different KE-I relations. Hence, the uncertainty associated with KE-I relations for soil erosion modelling is of critical importance.

A Review on Rainfall Erosivity (R factor) in Universal Soil Loss Equation

Land degradation caused by soil erosion by water can endanger the environment around the world. The estimation of soil erosion rates is mainly dependent on modeling rainfall erosivity, land use changes and influences of management on soil erosion rates. The model of soil erosion prediction often used by researchers around the world is Universal Soil Loss Equation (USLE). Rainfall amount and intensity are the most important variable for rainfall erosivity and written as the R factor in the USLE model. Among the factors in the USLE, rainfall erosivity is of high importance as precipitation is the main driver for soil erosion by water and has a direct impact on the detachment of soil particles, the breakdown of aggregates and the transport of eroded particles via runoff. USLE erosivity combines the energy of the rainfall and the maximum continuous 30-min intensity in the rainfall event. Energy of rainfall is estimated as a function of the storm intensity through the rainfall event.