The Use of Unmanned Aerial Vehicles (UAVs) for Estimating Soil Volumes Retained by Check Dams after Wildfires in Mediterranean Forests

Check dams act as soil collectors during floods, thus retaining a large amount of sediments. The estimation of the soil volumes stored behind a check dam is a key activity for a proper design of these control works and for evaluation of soil delivery after restoration measures at watershed level. Several topographic techniques have been proposed for this activity, but the sediment wedge mapping tools are complex and time consuming. Conversely, the use of unmanned aerial vehicles (UAVs) has been proposed to support aerophotogrammetric techniques for several survey activities with promising results. However, surveys by UAVs have never applied to calculate the size of the sediment wedge behind check dams that are built in fire-affected watersheds, where soil loss and sediment transport may be high after a wildfire. To fill this gap, this study evaluates the efficiency and efficacy of aerophotogrammetric surveys using UAVs to estimate the volume of the sediments stored behind ten check dams, built as post-fire channel treatment in a forest watershed of Castilla La Mancha (Central Eastern Spain). The results of the aerophotogrammetric technique were compared to traditional topographic surveys using a total station and GNSS/RTK, assumed as reference. The estimation of sediment wedge volume provided by UAVs was more accurate (mean RMSE of 0.432), extensive (density of mapped points of 328 m−2) and quick (two days of fieldwork) compared to surveys using the topographic method (RMSE < 0.04 m, six days of field work and density of mapped points of 0.194 m−2) by the topographic method. The differences in the sediment volume estimated by the two methods were not significant, but the UAV method was more accurate for the larger check dams. Moreover, a significant correlation was observed between the volume estimates provided by the two methods, shown by a coefficient of determination close to 0.98. Overall, these results propose a larger use of the aerial surveys for mapping activities in channels regulated by check dams, such as those built for restoration of fire-affected forest watersheds.

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Magnetic survey – ground technology, aeromagnetic survey on aircraft and unmanned aerial vehicles: a comparative analysis of the results (on the example of Eastern Transbaikalia)

Transbaikal State University Journal ◽

10.21209/2227-9245-2020-26-8-6-15 ◽

2020 ◽

Vol 26 (8) ◽

pp. 6-15

Author(s):

R. Gruzdev ◽

Keyword(s):

Unmanned Aerial Vehicles ◽

Geophysical Methods ◽

Work Productivity ◽

Field Work ◽

Magnetic Survey ◽

Aeromagnetic Survey ◽

Aerial Vehicles ◽

Eastern Transbaikalia ◽

Actual Material ◽

Ground Magnetic

The use of unmanned aerial vehicles (UAVs) in geophysical work is becoming a very popular area in the field of modern geological exploration. The advantage of unmanned systems is the optimal ratio of the quality of research results with a significant increase in work productivity and a decrease in cost. In this regard, the improvement of field techniques and the processing of UAV materials is of particular interest for exploration. On the subject, there are a number of unresolved issues that have been revealed to some extent as a result of the author’s comparison of ground-based magnetic exploration and aeromagnetic survey data. The purpose of the study was to assess the possibility of a full-fledged replacement of ground magnetic exploration work for aeromagnetic survey using unmanned aerial vehicles. The comparison of different types of magnetic survey is relevant, since on the basis of the actual material, the possibility of using an alternative more productive method – aeromagnetic survey using modern UAVs – instead of traditional expensive ground-based magnetic exploration works is analyzed. To compare the results of the studies, actual material obtained from field work on an area of 13,4 km2 was used. Based on the databases, maps of anomalous magnetic field and graphs on several geophysical profiles are built. Results of magnetic survey in air and ground versions are analyzed; correlation relationships between data of ground pedestrian magnetic survey and aeromagnetic system on An-3 and UAV aircraft are established. Based on the results of the study, correlation and determination coefficients were obtained, which indicate that geophysical methods on UAVs adequately occupy their place between classical aerogeophysics and ground-based pedestrian survey. Moreover, aeromagnetic survey using UAVs is able to replace pedestrian magnetic exploration during work at the same heights. Based on the results of the study, methodological recommendations for the production of aeromagnetic survey on UAVs were compiled

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Dye Tracing and Concentration Mapping in Coastal Waters Using Unmanned Aerial Vehicles

10.21203/rs.3.rs-882377/v1 ◽

2021 ◽

Author(s):

Kasper Johansen ◽

Aislinn F. Dunne ◽

Yu-Hsuan Tu ◽

Samir Almashharawi ◽

Burton H. Jones ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Coastal Water ◽

Dynamic Responses ◽

Coefficient Of Determination ◽

Complex Nature ◽

Dye Tracing ◽

Water Flows ◽

Tidal Interactions ◽

Aerial Vehicles ◽

Uav Images

Abstract Coastal water flows facilitate important nutrient exchanges between mangroves, seagrasses and coral reefs. However, due to the complex nature of tidal interactions, their spatiotemporal development can be difficult to trace via traditional field instrumentations. Unmanned aerial vehicles (UAVs) serve as ideal platforms from which to capture such dynamic responses. Here, we provide a UAV-based approach for tracing coastal water flows using object-based detection of dye plume extent coupled with a regression approach for mapping dye concentration. From hovering UAV images and nine subsequent flight surveys covering the duration of an ebbing tide in the Red Sea, our results show that dye plume extent can be mapped with low omission and commission errors when assessed against manual delineations. Our results also demonstrated that the interaction term of two UAV-derived indices may be employed to accurately map dye concentration (coefficient of determination = 0.96, root mean square error = 7.78 ppb), providing insights into vertical and horizontal transportation and dilution of materials in the water column. We showcase the capabilities of high-frequency UAV-derived data and demonstrate how field-based dye concentration measurements can be integrated with UAV data for future studies of coastal water flow dynamics.

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Unmanned Aerial Vehicle – Efficient mapping tool available for recent research in polar regions

Czech Polar Reports ◽

10.5817/cpr2015-2-18 ◽

2015 ◽

Vol 5 (2) ◽

pp. 210-221 ◽

Cited By ~ 8

Author(s):

Radim Stuchlík ◽

Zdeněk Stachoň ◽

Kamil Láska ◽

Petr Kubíček

Keyword(s):

Unmanned Aerial Vehicles ◽

Field Work ◽

Polar Regions ◽

Svalbard Archipelago ◽

Mapping Tool ◽

Aerial Vehicles ◽

Aerial Vehicle ◽

Harsh Climate ◽

Near Future

Unmanned Aerial Vehicles (UAV) have technical capabilities to extended usage in various fields ofscience. The existing UAVs are to be relatively easily accessible in the near future. It is possible to equip them with different sensors but there are still some usage limitations. This paper focuses ondemonstrating UAVs usage for research in polar regions. The research in polar regions is very specific and, due to harsh climate, limits the field work with UAVs. The options and limitations are presented in a case study performed in the Nordenskiöldbreen area, Svalbard Archipelago. In the end some derived products suitable for further analysis are presented.

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Development of thickened semi-synthetic engine oil M-5z / 20 AERO for four-stroke gasoline engines aircraft piston of unmanned aerial vehicles (UAVs)

World of OIL Products the Oil Companies Bulletin ◽

10.32758/2071-5951-2020-0-6-44-47 ◽

2020 ◽

Vol 06 ◽

pp. 44-47

Author(s):

A.A. Moykin ◽

◽

A.S. Medzhibovsky ◽

S.A. Kriushin ◽

M.V. Seleznev ◽

...

Keyword(s):

Unmanned Aerial Vehicles ◽

Engine Oil ◽

Motor Oil ◽

Gasoline Engines ◽

State Research Institute ◽

Technical Requirements ◽

Aerial Vehicles ◽

State Research ◽

Industrial Batch ◽

The Russian Federation

Nowadays, the creation of remotely-piloted aerial vehicles for various purposes is regarded as one of the most relevant and promising trends of aircraft development. FAU "25 State Research Institute of Chemmotology of the Ministry of Defense of the Russian Federation" have studied the operation features of aircraft piston engines and developed technical requirements for motor oil for piston four-stroke UAV engines, as well as a new engine oil M-5z/20 AERO in cooperation with NPP KVALITET, LLC. Based on the complex of qualification tests, the stated operational properties of the experimental-industrial batch of M-5z/20 AERO oil are generally confirmed.

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