Assesment of Soil Degradation: Water Erosion under Systematic UAV Supervision

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F23%3A00370935" target="_blank" >RIV/68407700:21110/23:00370935 - isvavai.cz</a>

Result on the web

<a href="https://tud.qucosa.de/api/qucosa%3A87480/attachment/ATT-0/" target="_blank" >https://tud.qucosa.de/api/qucosa%3A87480/attachment/ATT-0/</a>

DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Assesment of Soil Degradation: Water Erosion under Systematic UAV Supervision

Original language description

This contribution presents the principles of long-term monitoring of experimental sites in terms of accelerated soil degradation caused by water erosion. Within several different projects, agricultural land near the villages of Býkovice and Nučice in the Central Bohemian Region is monitored for a long time. Data on rainfall, tem-perature and soil moisture are monitored using meteorological stations on the defined soil plots. At regular intervals or after a significant rainfall event (above 10 mm/24 h), field surveys are carried out, including moni-toring of the areas by UAVs. Since the start of systematic monitoring in 2017, a total of 124 monitoring cam-paigns using UAVs have been carried out until the end of 2022. Approximately 1-6 flights have been conducted per campaign, with an average area per flight of 0.25 km2 and an average resolution of 2.2 cm/px. The primary drone used for the flights since 2022 is a DJI M300 with a Zenmuse P1 camera and 24 mm lens. A DJI Phantom 4 RTK is also used for smaller land areas. These new drones are used in RTK mode, which makes it possible to obtain positional and height accuracy within 10 cm, compared to several meters for older drones (DJI Phantom 4) without RTK and without additional georeferencing. The processing of the flight images is done in Agisoft Metashape software. Using this software, digital terrain models and an orthophotomap (Fig. 1) in raster TIFF format in the S-JTSK coordinate system (EPSG: 5514) and Bpv elevation system (EPSG: 5705) are obtained by partial steps (Align photos - Detect markers - Build Dense Cloude - Filter by Confidence or Manually - Build DEM - Build Ortohomosaic). These outputs are further processed in a GIS environment to identify erosion features such as rills, furrows, sheet erosion or sedimenta-tion. This step is automated by the GIS tool using the method according to Báčová et al. (2019), (Fig. 2). The input to the tool is a digital terrain model and a polygon layer with rill boundaries, which is created manually. The tool then creates a TIN from the rill boundary and the terrain model, from which it then subtracts the terrain model with the rill to obtain the rill volume, or the volume of rill erosion. The resulting soil erosion volume in the rills only, ranged from 26 to 285 m3. The conversion to the commonly used unit t/ha depends on the area to which the rills relate. In the case of the single rill polygon these values range from 215 to 566 t/ha, in the case of the corresponding LPIS parcel from 2.2 to 17.8 t/ha and in the case of the corresponding sub-basin from 5.5 to 56.8 t/ha. From this basic overview it can be seen how much soil is lost to rill erosion. In this way, all the areas where evidences of rill erosion are visible and for which rainfall data are available are processed in turn. In the next stages of the solution, it is planned to continuously acquire additional data and compare the measured soil erosion volumes with the erosion models and with the data measured using rainfall simulators. Acknowledgements: Research has been supported by project TUDI (European Union's Horizon 2020 research and innovation programme under grant agreement No 101000224), SS05010180: Updating concept of the tol-erable soil loss from arable land and SGS23/155/OHK1/3T/11: Experimental research and monitoring of rain-fall-runoff and erosion processes on agricultural soils.

Czech name

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Czech description

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Type

O - Miscellaneous

CEP classification

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OECD FORD branch

20705 - Remote sensing

Project

<a href="/en/project/SS05010180" target="_blank" >SS05010180: Updating concept of the tolerable soil loss from arable land</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů