A Protocol for Aerial Survey in Coastal Areas Using UAS

Doukari, Michaela; Batsaris, Marios; Παπακωνσταντίνου, Απόστολος; Topouzelis, Konstantinos

doi:10.3390/rs11161913

Cited by 40 publications

(41 citation statements)

References 37 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Aerial observations and in situ measurements of the Kodor plume were conducted on 1-2 September 2018 and 1-3 April 2019, while aerial observations and in situ measurements of the Bzyp plume were performed on 31 May-1 June 2019. Below we provide the protocols of these aerial surveys according to the scheme suggested by Doukari et al [74].…”

Section: Aerial In Situ and Satellite Datamentioning

confidence: 99%

Spatial Structure, Short-temporal Variability, and Dynamical Features of Small River Plumes as Observed by Aerial Drones: Case Study of the Kodor and Bzyp River Plumes

et al. 2020

View full text Add to dashboard Cite

Quadcopters can continuously observe ocean surface with high spatial resolution from relatively low altitude, albeit with certain limitations of their usage. Remote sensing from quadcopters provides unprecedented ability to study small river plumes formed in the coastal sea. The main goal of the current work is to describe structure and temporal variability of small river plumes on small spatial and temporal scales, which are limitedly covered by previous studies. We analyze optical imagery and video records acquired by quadcopters and accompanied by synchronous in situ measurements and satellite observations within the Kodor and Bzyp plumes, which are located in the northeastern part of the Black Sea. We describe extremely rapid response of these river plume to energetic rotating coastal eddies. We reveal several types of internal waves within these river plumes, measure their spatial and dynamical characteristics, and identify mechanisms of their generation. We suggest a new mechanism of formation of undulate fronts between small river plumes and ambient sea, which induces energetic lateral mixing across these fronts. The results reported in this study are addressed for the first time as previous related works were mainly limited by low spatial and/or temporal resolution of in situ measurements and satellite imagery.

show abstract

Section: Aerial In Situ and Satellite Datamentioning

confidence: 99%

Spatial Structure, Short-temporal Variability, and Dynamical Features of Small River Plumes as Observed by Aerial Drones: Case Study of the Kodor and Bzyp River Plumes

et al. 2020

View full text Add to dashboard Cite

show abstract

“…These anomalies appeared due to different illumination conditions and the sun glint; therefore, the multispectral orthomosaic classification presents lower accuracy values. It is crucial to follow a specific UAS flight protocol before each data acquisition, as presented by Doukari et al in [29,43], for eliminating these anomalies. It should be mentioned that the UAS data acquisition procedure works fine over land, presenting a high accuracy level.…”

Section: Discussionmentioning

confidence: 99%

“…Data acquisition took place on the 8 th July 2018 in the Pamfila area. Before the data acquisition, the UAS toolbox was used to predict the optimal flight time [29]. The toolbox automates a protocol, which summarizes the parameters that affect the reliability and the quality of the data acquisition process over the marine environment using UAS.…”

Section: Flight Parametersmentioning

confidence: 99%

Comparison of True-Color and Multispectral Unmanned Aerial Systems Imagery for Marine Habitat Mapping Using Object-Based Image Analysis

Παπακωνσταντίνου¹,

Stamati²,

Topouzelis³

2020

Remote Sensing

Self Cite

View full text Add to dashboard Cite

The use of unmanned aerial systems (UAS) over the past years has exploded due to their agility and ability to image an area with high-end products. UAS are a low-cost method for close remote sensing, giving scientists high-resolution data with limited deployment time, accessing even the most inaccessible areas. This study aims to produce marine habitat mapping by comparing the results produced from true-color RGB (tc-RGB) and multispectral high-resolution orthomosaics derived from UAS geodata using object-based image analysis (OBIA). The aerial data was acquired using two different types of sensors-one true-color RGB and one multispectral-both attached to a UAS, capturing images simultaneously. Additionally, divers' underwater images and echo sounder measurements were collected as in situ data. The produced orthomosaics were processed using three scenarios by applying different classifiers for the marine habitat classification. In the first and second scenario, the k-nearest neighbor (k-NN) and fuzzy rules were applied as classifiers, respectively. In the third scenario, fuzzy rules were applied in the echo sounder data to create samples for the classification process, and then the k-NN algorithm was used as the classifier. The in situ data collected were used as reference and training data. Additionally, these data were used for the calculation of the overall accuracy of the OBIA process in all scenarios. The classification results of the three scenarios were compared. Using tc-RGB instead of multispectral data provides better accuracy in detecting and classifying marine habitats when applying the k-NN as the classifier. In this case, the overall accuracy was 79%, and the Kappa index of agreement (KIA) was equal to 0.71, which illustrates the effectiveness of the proposed approach. The results showed that sub-decimeter resolution UAS data revealed the sub-bottom complexity to a large extent in relatively shallow areas as they provide accurate information that permits the habitat mapping in extreme detail. The produced habitat datasets are ideal as reference data for studying complex coastal environments using satellite imagery.

show abstract

“…The randomisation of survey direction to reduce bias in sampling created issues with glare, as glare can be minimised by keeping the sun orientated behind the aircraft (Kay, Hedley, & Lavender, 2009). By surveying on overcast days and considering sun angles glare can be reduced (Doukari, Batsaris, Papakonstantinou, & Topouzelis, 2019; Joyce, Duce, Leahy, Leon, & Maier, 2019), but this may limit the utility of drones when survey methods involve using randomised direction. The spacing of the ground stations was fortuitous in this study, but the lack of appropriate operational areas may also limit the utility of drones in other areas, in addition to restricted airspace.…”

Section: Discussionmentioning

confidence: 99%

Assessing the viability of small aerial drones to quantify recreational fishers

Provost

Butcher

Coleman

et al. 2020

Fisheries Management Eco

View full text Add to dashboard Cite

Understanding fishing participation assists sustainable fisheries management. Relative to commercial fisheries, however, accurate quantitative data on recreational fishing is often more challenging to collect. The quality and robustness of recreational fishing surveys to assess fisher numbers may be improved with cost‐effective remote sensing platforms, such as aerial drones. Here, the precision and cost‐effectiveness of drone‐based surveys were compared with more traditional vessel‐based surveys of recreational fishing participation at four locations on the east coast of Australia. Although vessel‐based surveys had greater initial costs, this technique observed more fishers, took less time to complete and did not require post‐processing of video footage. In comparison, the drone‐based video surveys provided greater precision and a permanent record of fishing activity. Currently, drone‐based techniques do not provide a substantial improvement to traditional vessel‐based counts of fishers. The complimentary use of drones appears to be an appropriate application of this technology for supporting fisheries management.

show abstract

A Protocol for Aerial Survey in Coastal Areas Using UAS

Cited by 40 publications

References 37 publications

Spatial Structure, Short-temporal Variability, and Dynamical Features of Small River Plumes as Observed by Aerial Drones: Case Study of the Kodor and Bzyp River Plumes

Spatial Structure, Short-temporal Variability, and Dynamical Features of Small River Plumes as Observed by Aerial Drones: Case Study of the Kodor and Bzyp River Plumes

Comparison of True-Color and Multispectral Unmanned Aerial Systems Imagery for Marine Habitat Mapping Using Object-Based Image Analysis

Assessing the viability of small aerial drones to quantify recreational fishers

Contact Info

Product

Resources

About