An assessment of soil water erosion in the Myjava hill land: The application of a physically-based erosion model

The scope of this study is an evaluation of potential soil water erosion using the physically-based erosion model, EROSION-3D. This model is event-based and calculates soil water erosion during an actual measured rainfall event. The calculations of the erosion model take advantage of a digital elevation model, precipitation and soil parameters, which are established in a specific parameter catalogue. The soil water erosion was modeled in two small catchments in the Myjava Hill Land (Slovakia), using 9 soil moisture scenarios and two different crops on arable areas. When considering the last 35 years of rainfall records at the Myjava meteorological station, three storm rainfall events were applied in the modeling. The results were statistically analyzed to figure out the differences between the model’s functional possibilities; the modeling under the various scenarios proved a strong interaction between the values of the input factors and the results of the soil erosion

Sedimentace v malých vodních nádržích

V současné době roste počet malých vodních nádrží v Česku i na Slovensku, které mají dva hlavní úkoly – protipovodňová ochrana a zásoba vody pro období sucha. Tyto malé vodní nádrže se často objevují v zemědělských oblastech, kde je velký potenciál jejich využití. Problém těchto oblastí je silná eroze půdy, která vede k odnosu a následnému uložení erodovaného materiálu v nádržích či nad jinými překážkami. Takto uložené sedimenty snižují retenční kapacitu nádrže, zvyšují koncentraci chemických látek, což vše může vést ke zhoršení kvality vody v nádrži i pod ní. Tento příspěvek se zaměřuje na dvě malé nádrže vybudované v roce 2011, u kterých se od uvedení do provozu sleduje množství uložených sedimentů. Jsou zde představeny dvě různé metody, jak odvodit množství sedimentů z měření vývoje dna nádrže, včetně možné aplikace empirických erozních modelů pro stanovení potenciálního množství erodovaného materiálu. Důraz je také kladen na terénní průzkum pro odběr vzorků půdy a jejich následnou laboratorní analýzu. Takto získané informace mohou pomoci k pochopení transportních i depozičních procesů v nádrži a odpovídající přispívající ploše (povodí). Výsledky poukazují na relativně rychlé zanášení malých vodních nádrží v zemědělské krajině zejména díky intenzivním srážkovým událostem. Množství sedimentů nezávisí na typu nádrže (suchá nebo se stálou hladinou), ale na charakteru povodí (fyzicko-geografické vlastnosti území), využití území a pěstovaných plodinách.The uncontrolled reservoir siltation presents a hazard together with the rising number of reservoirs and current climate change. This paper presents the possible methodologies to measure siltation in small reservoir and how to calculate the potential soil water erosion and deposition of the contributing area. The results show that the USLE-based erosion models are suitable for estimation of erosion processes, especially USPED model, which is capable to model erosion and deposition of the material in the same time. Also, both approaches to investigate the development of the reservoir bottom were verified. The use of AUV EcoMapper is appropriate for reservoirs with stable water level between 1 and 100 meters, however the second approach is more suitable for shallow reservoirs. According to observed and modelled sediment budget of reservoirs the supposed reservoir lifetime was determined from 100 to 400 years. The siltation is much higher in the Svacenický reservoir in contrast to Němčický reservoir (Suchý creek catchment), which corresponds to bigger catchment area, higher percentage of arable land and more variable relief

Assessment of potential soil water erosion based on empirical and physicall models: the case study in the Myjava Hill Land, Slovakia

The results confirmed our opinion that the extreme rainfall events cause hazardous erosion processes, especially in the agricultural areas of the Myjava Hills. The modelled sediment yields were compared with the measured data obtained by the bathymetry measurement in the Svacenický polder located in the bottom of the Svacenický catchment. The AUV (Autonomous Underwater Vehicle) device EcoMapper was used for the mapping of bed sediments of the polder. This device is an effective tool of hydrographical survey, which investigates bathymetry of a reservoir with a high-resolution

Determination of SCS-CN Initial Abstraction Ratio in a Catchment Prone to Flash Floods

The soil conservation service - curve number method is a globally used approach to simulations of surface runoff for its simplicity and applicability. Nevertheless, relevant simulations require proper setting of the model’s components. This work focuses on optimization of initial abstraction ratio λ in the Husí potok sub-catchments in Czech Republic. Due to favorable morphology, the watershed is prone to flash floods and accurate modeling of surface runoff is of high interest. The analysis was conducted using pairs of discharge and rainfall measurements. The results outline that the traditional value λ= 0.2 is too high in this watershed and should be reduced

Improvement of SCS-CN Initial Abstraction Coefficient in the Czech Republic: A Study of Five Catchments

The SCS-CN method is a globally known procedure used primarily for direct-runoff estimates. It also is integrated in many modelling applications. However, the method was developed in specific geographical conditions, often making its universal applicability problematic. This study aims to determine appropriate values of initial abstraction coefficients λ and curve numbers (CNs), based on measured data in five experimental catchments in the Czech Republic, well representing the physiographic conditions in Central Europe, to improve direct-runoff estimates. Captured rainfall-runoff events were split into calibration and validation datasets. The calibration dataset was analysed by applying three approaches: (1) Modifying λ, both discrete and interpolated, using the tabulated CN values; (2) event analysis based on accumulated rainfall depth at the moment runoff starts to form; and (3) model fitting, an iterative procedure, to search for a pair of λ, S (CN, respectively). To assess individual rainfall characteristics’ possible influence, a principal component analysis and cluster analysis were conducted. The results indicate that the CN method in its traditional arrangement is not very applicable in the five experimental catchments and demands corresponding modifications to determine λ and CN (or S, respectively). Both λ and CN should be viewed as flexible, catchment-dependent (regional) parameters, rather than fixed values. The acquired findings show the need for a systematic yet site-specific revision of the traditional CN method, which may help to improve the accuracy of CN-based rainfall-runoff modelling

Sensitivity Analysis of Soil Parameters and Their Impact on Runoff-Erosion Processes

The modeling of soil erosion processes is affected by several factors that reflect the physical-geographic conditions of the study site together with the land use linkage. The soil parameters are significant in the modeling of erosion and also runoff processes. The correct determination of a soil’s parameters becomes a crucial part of the model’s calibration. This paper deals with a sensitivity analysis of seven soil input parameters to the physically-based Erosion 3D model. The results show the variable influence of each soil parameter. The Erosion 3D model is very sensitive to initial soil moisture, bulk density, and erodibility

Remote Sensing of Riparian Ecosystems

Riparian zones are dynamic ecosystems that form at the interface between the aquatic and terrestrial components of a landscape. They are shaped by complex interactions between the biophysical components of river systems, including hydrology, geomorphology, and vegetation. Remote sensing technology is a powerful tool useful for understanding riparian form, function, and change over time, as it allows for the continuous collection of geospatial data over large areas. This paper provides an overview of studies published from 1991 to 2021 that have used remote sensing techniques to map and understand the processes that shape riparian habitats and their ecological functions. In total, 257 articles were reviewed and organised into six main categories (physical channel properties; morphology and vegetation or field survey; canopy detection; application of vegetation and water indices; riparian vegetation; and fauna habitat assessment). The majority of studies used aerial RGB imagery for river reaches up to 100 km in length and Landsat satellite imagery for river reaches from 100 to 1000 km in length. During the recent decade, UAVs (unmanned aerial vehicles) have been widely used for low-cost monitoring and mapping of riverine and riparian environments. However, the transfer of RS data to managers and stakeholders for systematic monitoring as a source of decision making for and successful management of riparian zones remains one of the main challenges

Remote Sensing of Riparian Ecosystems

Riparian zones are dynamic ecosystems that form at the interface between the aquatic and terrestrial components of a landscape. They are shaped by complex interactions between the biophysical components of river systems, including hydrology, geomorphology, and vegetation. Remote sensing technology is a powerful tool useful for understanding riparian form, function, and change over time, as it allows for the continuous collection of geospatial data over large areas. This paper provides an overview of studies published from 1991 to 2021 that have used remote sensing techniques to map and understand the processes that shape riparian habitats and their ecological functions. In total, 257 articles were reviewed and organised into six main categories (physical channel properties; morphology and vegetation or field survey; canopy detection; application of vegetation and water indices; riparian vegetation; and fauna habitat assessment). The majority of studies used aerial RGB imagery for river reaches up to 100 km in length and Landsat satellite imagery for river reaches from 100 to 1000 km in length. During the recent decade, UAVs (unmanned aerial vehicles) have been widely used for low-cost monitoring and mapping of riverine and riparian environments. However, the transfer of RS data to managers and stakeholders for systematic monitoring as a source of decision making for and successful management of riparian zones remains one of the main challenges

Detailed assessment of spatial and temporal variations in river channel changes and meander evolution as a preliminary work for effective floodplain management. The example of Sajó River, Hungary

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