{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T19:44:08Z","timestamp":1775072648300,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,30]],"date-time":"2021-04-30T00:00:00Z","timestamp":1619740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ATTRACT Project (European Comission)","award":["777222"],"award-info":[{"award-number":["777222"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Wastewater treatment plants (WWTPs) are sources of greenhouse gases, hazardous air pollutants and offensive odors. These emissions can have negative repercussions in and around the plant, degrading the quality of life of surrounding neighborhoods, damaging the environment, and reducing employee\u2019s overall job satisfaction. Current monitoring methodologies based on fixed gas detectors and sporadic olfactometric measurements (human panels) do not allow for an accurate spatial representation of such emissions. In this paper we use a small drone equipped with an array of electrochemical and metal oxide (MOX) sensors for mapping odorous gases in a mid-sized WWTP. An innovative sampling system based on two (10 m long) flexible tubes hanging from the drone allowed near-source sampling from a safe distance with negligible influence from the downwash of the drone\u2019s propellers. The proposed platform is very convenient for monitoring hard-to-reach emission sources, such as the plant\u2019s deodorization chimney, which turned out to be responsible for the strongest odor emissions. The geo-localized measurements visualized in the form of a two-dimensional (2D) gas concentration map revealed the main emission hotspots where abatement solutions were needed. A principal component analysis (PCA) of the multivariate sensor signals suggests that the proposed system can also be used to trace which emission source is responsible for a certain measurement.<\/jats:p>","DOI":"10.3390\/rs13091757","type":"journal-article","created":{"date-parts":[[2021,5,1]],"date-time":"2021-05-01T21:35:39Z","timestamp":1619904939000},"page":"1757","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Aerial Mapping of Odorous Gases in a Wastewater Treatment Plant Using a Small Drone"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7327-6396","authenticated-orcid":false,"given":"Javier","family":"Burgu\u00e9s","sequence":"first","affiliation":[{"name":"Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 10-12, 08028 Barcelona, Spain"},{"name":"The Barcelona Institute of Science and Technology, Carrer del Comte d\u2019Urgell 187, 08036 Barcelona, Spain"},{"name":"Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Marti i Franqu\u00e9s 1, 08028 Barcelona, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2946-9841","authenticated-orcid":false,"given":"Mar\u00eda Deseada","family":"Esclapez","sequence":"additional","affiliation":[{"name":"Depuraci\u00f3n de Aguas del Mediterr\u00e1neo (DAM), Avenida Benjam\u00edn Franklin 21, Parque Tecnol\u00f3gico, 46980 Paterna, Spain"}]},{"given":"Silvia","family":"Do\u00f1ate","sequence":"additional","affiliation":[{"name":"Depuraci\u00f3n de Aguas del Mediterr\u00e1neo (DAM), Avenida Benjam\u00edn Franklin 21, Parque Tecnol\u00f3gico, 46980 Paterna, Spain"}]},{"given":"Laura","family":"Pastor","sequence":"additional","affiliation":[{"name":"Depuraci\u00f3n de Aguas del Mediterr\u00e1neo (DAM), Avenida Benjam\u00edn Franklin 21, Parque Tecnol\u00f3gico, 46980 Paterna, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2663-2965","authenticated-orcid":false,"given":"Santiago","family":"Marco","sequence":"additional","affiliation":[{"name":"Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 10-12, 08028 Barcelona, Spain"},{"name":"The Barcelona Institute of Science and Technology, Carrer del Comte d\u2019Urgell 187, 08036 Barcelona, Spain"},{"name":"Department of Electronics and Biomedical Engineering, Universitat de Barcelona, Marti i Franqu\u00e9s 1, 08028 Barcelona, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,30]]},"reference":[{"key":"ref_1","unstructured":"Agency, E.E. 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