Mapping eelgrass beds with orthophotos

Research output: Contribution to conferenceConference abstract for conferenceResearch

Mapping the distribution of eelgrass is important for optimal management of eelgrass meadows, a key organism in coastal ecosystems. The many ecosystem functions and services that eelgrass beds provide, scale directly with their distribution area. We have evaluated the potential in using orthophotos, that Aarhus University has bought for other purposes, to map and quantify eelgrass distribution. Based on photos from the summers of 2012, 2014 and 2016, in combination with monitoring data on eelgrass, we developed image analysis techniques applied to RGB color bands and analyzed orthophotos from selected, important eelgrass areas in Denmark: Nibe-Gjøl Bredninger in Limfjorden, Saltholm incl. the Amager coast facing Saltholm, the Southfunen Archipelago and Roskilde Fjord. The analysis displayed good precision with less than 5% uncertainty, validated by ground truth monitoring data. Good measures of eelgrass distribution areas and patterns will contribute to a better understanding of the ecosystems services and the socioeconomic value of eelgrass meadows at larger scales. We show that mapping eelgrass distribution by image analysis of orthophotos serves as a readily applicable method. Orthophotos are often available in relatively long continuous time series, offering the opportunity to observe longterm patterns in distribution and how they may be affected by different levels of environmental status in associated water bodies.
Original languageEnglish
Publication year2018
Publication statusPublished - 2018
Event4th International Symposium on Research and Management of Eutrophication in Coastal Ecosystems - Nyborg, Denmark
Duration: 18 Jun 201820 Jun 2018


Conference4th International Symposium on Research and Management of Eutrophication in Coastal Ecosystems
Internet address

See relations at Aarhus University Citationformats

ID: 139199395