1 Data information

This visualization product shows the density of seafloor litter per trawl per year. EMODnet Chemistry included the gathering of marine litter in its 3rd phase. Since the beginning of 2018, data of seafloor litter collected by international fish-trawl surveys have been gathered and processed in the EMODnet Chemistry Marine Litter Database (MLDB). The harmonization of all the data has been the most challenging task considering the heterogeneity of the data sources, sampling protocols (OSPAR and MEDITS protocols) and reference lists used on a European scale. Moreover, within the same protocol, different gear types are deployed during fishing bottom trawl surveys. To calculate the density, the swept area of the trawl is required. The swept area is calculated from the wingspread (which depends on the fishing gear type) and the distance trawled. In the cases were the wingspread and/or the trawled distance are unknown, effective values were calculated from available information, when possible, specifically, the distance: Distance =Haul duration Ground speed While the calculation of the effective wingspread is based in a general formula (van Hal, 2017) which considers other parameters known of the net, thus introducing some inaccuracies: Wingspread=doordpread0.18870+5.87280 Doorspread = 14.2 * log(Depth) = 16.72 * log(Warp_length) + 18.49 This method may be improved in the future. The used formula for the swept area and density is: Density (number of items per km^2)= (total number of items)/(Swept area) Percentiles 50, 75 & 95 have been calculated taking into account data from all years. More information is available in the following document: https://www.emodnet-chemistry.eu/repository/20190321_EMODnet_Beach_Seabed_ML_Products.pdf

1.1 Metadata

Access metadata from landing page

3 Seabed litter - Density (Nb. Items/km^2)

3.1 Access data

The Web Feature Service (WFS) of the EMODnet Chemistry portal allows collecting the data:
https://www.ifremer.fr/services/wfs/emodnet_chemistry2?service=WFS&request=GetCapabilities&version=1.1.0

Available labels:

##  [1] "msGeometry"              "id"                     
##  [3] "country"                 "country_name"           
##  [5] "survey_id"               "surveyname"             
##  [7] "ship"                    "ship_name"              
##  [9] "gear"                    "gear_description"       
## [11] "project_id"              "stno"                   
## [13] "haulno"                  "surveyyear"             
## [15] "year"                    "date"                   
## [17] "shot_timestamp"          "distance_km"            
## [19] "netopening_km"           "ltref"                  
## [21] "littercount_by_squarekm" "littercount_by_ha"      
## [23] "geom_pointline"


Download data for the defined geographical extent:

Excel file Geographic information
csv geojson

3.2 Table

Browse table’s columns by using the left and right arrows. Turn the table’s pages with help of the previous/next buttons.

3.3 Map

3.4 Map with id

3.5 Interactive map

Visualise and access data with Openlayer (click on the map)

4 Litter abundance per year