Nutrients in Europe's transitional, coastal and marine waters

Eutrophication in marine, coastal and estuarine ecosystems, caused by human activities that introduce excess nutrients into water, lead to harmful effects. To address this, Europe adopted an integrated strategy to reduce inputs. Nutrient levels have significantly declined between 1980 and 2023, yet eutrophication remains a significant problem in the Baltic, Black and Greater North Seas and some coastal areas of the Mediterranean Sea. Over 91-94% of the assessed time-series show no significant change. Progress has been made to reduce nutrient inputs, specifically nitrogen, yet more effort is necessary for phosphorus.

Lead Image No image
Lead Image Caption
Metadata
DPSIR Response
Typology Performance indicator (Type B - Does it matter?)
UN SDGs SDG14: Life below water
Topics Water, Agriculture and food, Seas and coasts
Temporal coverage { "readOnly": true, "temporal": [ { "label": "1980", "value": "1980" }, { "label": "1981", "value": "1981" }, { "label": "1982", "value": "1982" }, { "label": "1983", "value": "1983" }, { "label": "1984", "value": "1984" }, { "label": "1985", "value": "1985" }, { "label": "1986", "value": "1986" }, { "label": "1987", "value": "1987" }, { "label": "1988", "value": "1988" }, { "label": "1989", "value": "1989" }, { "label": "1990", "value": "1990" }, { "label": "1991", "value": "1991" }, { "label": "1992", "value": "1992" }, { "label": "1993", "value": "1993" }, { "label": "1994", "value": "1994" }, { "label": "1995", "value": "1995" }, { "label": "1996", "value": "1996" }, { "label": "1997", "value": "1997" }, { "label": "1998", "value": "1998" }, { "label": "1999", "value": "1999" }, { "label": "2000", "value": "2000" }, { "label": "2001", "value": "2001" }, { "label": "2002", "value": "2002" }, { "label": "2003", "value": "2003" }, { "label": "2004", "value": "2004" }, { "label": "2005", "value": "2005" }, { "label": "2006", "value": "2006" }, { "label": "2007", "value": "2007" }, { "label": "2008", "value": "2008" }, { "label": "2009", "value": "2009" }, { "label": "2010", "value": "2010" }, { "label": "2011", "value": "2011" }, { "label": "2012", "value": "2012" }, { "label": "2013", "value": "2013" }, { "label": "2014", "value": "2014" }, { "label": "2015", "value": "2015" }, { "label": "2016", "value": "2016" }, { "label": "2017", "value": "2017" }, { "label": "2018", "value": "2018" }, { "label": "2019", "value": "2019" }, { "label": "2020", "value": "2020" }, { "label": "2021", "value": "2021" }, { "label": "2022", "value": "2022" }, { "label": "2023", "value": "2023" } ] }
Geographic coverage { "readOnly": true, "geolocation": [ { "label": "Baltic Sea", "value": "geo-2633321" }, { "label": "Bay of Biscay", "value": "geo-2960858" }, { "label": "Black Sea", "value": "geo-630673" }, { "label": "Celtic Seas", "value": "CSEA" }, { "label": "Greater North Sea", "value": "NSEA" }, { "label": "Iberian Coast", "value": "IC" }, { "label": "Macaronesia", "value": "MAC" }, { "label": "Mediterranean Sea", "value": "geo-363196" }, { "label": "North-East Atlantic Ocean", "value": "MATL" } ] }
Workflow
Content responsible Head of Group Trine Christiansen
Layout
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To address this, Europe adopted an integrated strategy to reduce inputs. Nutrient levels have significantly declined between 1980 and 2023, yet eutrophication remains a significant problem in the Baltic, Black and Greater North Seas and some coastal areas of the Mediterranean Sea. Over 91-94% of the assessed time-series show no significant change. Progress has been made to reduce nutrient inputs, specifically nitrogen, yet more effort is necessary for phosphorus.", "readOnlySettings": true, "required": true, "value": [ { "children": [ { "text": "\nEutrophication in marine, coastal and estuarine ecosystems, caused by human activities that introduce excess nutrients into water, lead to harmful effects. To address this, Europe adopted an integrated strategy to reduce inputs. Nutrient levels have significantly declined between 1980 and 2023, yet eutrophication remains a significant problem in the Baltic, Black and Greater North Seas and some coastal areas of the Mediterranean Sea. Over 91-94% of the assessed time-series show no significant change. Progress has been made to reduce nutrient inputs, specifically nitrogen, yet more effort is necessary for phosphorus. 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The number of time series present for the Baltic and Greater North Seas are larger than the Mediterranean and Black Seas. Figure 2 illustrates the distribution of trends based on available time-series data across regional seas and all of Europe\u2019s seas.", "value": [ { "children": [ { "text": "The availability of time series data for the assessment of nutrient levels varies across regional seas. The number of time series present for the Baltic and Greater North Seas are larger than the Mediterranean and Black Seas. Figure 2 illustrates the " }, { "children": [ { "text": "distribution of trends" } ], "type": "strong" }, { "text": " based on available time-series data across regional seas and all of Europe\u2019s seas. " } ], "type": "p" } ] }, "7dd27cae-b474-4043-ab8f-72267ac4abd8": { "@type": "group", "className": "figure-metadata", "data": { "blocks": { "9148bf22-ce4a-4206-b5e0-3b1e67dc2515": { "@type": "slate", "plaintext": "Figure 2. Number of time series available showing increasing, decreasing or no trends in dissolved inorganic nitrogen and orthophosphate concentrations for each regional sea for two time periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)", "value": [ { "children": [ { "text": "Figure 2. Number of time series available showing increasing, decreasing or no trends in dissolved inorganic nitrogen and orthophosphate concentrations for each regional sea for two time periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)" } ], "type": "h3-light" } ] } }, "blocks_layout": { "items": [ "9148bf22-ce4a-4206-b5e0-3b1e67dc2515" ] } }, "id": "figure-metadata-02ba4a04-fcfe-4968-806f-1dac3119cfef", "styles": {} }, "9c322e5e-9769-4289-a80a-123ecc00e21d": { "@type": "slate", "plaintext": "DIP levels have continued to decline in the Greater North Sea. However, the number of assessed trends is much less than pre 2000 for the Black Sea. The availability of time series data is crucial for assessing the state of European seas and evaluating the effectiveness of measures taken to achieve good status.", "value": [ { "children": [ { "text": "DIP levels have continued to decline in the Greater North Sea. However, the number of assessed trends is much less than pre 2000 for the Black Sea. The availability of time series data is crucial for assessing the state of European seas and evaluating the effectiveness of measures taken to achieve good status." } ], "type": "p" } ] }, "b6828732-2f48-48b7-bb29-fc082f80b112": { "@type": "slate", "plaintext": "", "value": [ { "children": [ { "text": " " } ], "type": "p" } ] }, "c878c640-e945-41d7-b1fe-77b22b035794": { "@type": "slate", "plaintext": "Since 2000, DIN concentrations have been decreasing in the Greater North and Baltic Seas. However, before 2000, declines were observed in the Black Sea. Fewer increasing trends in DIN, post 2000, suggest reductions in nutrient inputs as a result of EU policy implementation . Decreasing trends have become less common for DIP after 2000, with increasing trends observed in both the Baltic and Black Seas (11% each). This rise in DIP concentrations is likely due to phosphorus release from sediment under anoxic conditions .", "value": [ { "children": [ { "text": "Since 2000, DIN concentrations have been decreasing in the Greater North and Baltic Seas. However, before 2000, declines were observed in the Black Sea. Fewer increasing trends in DIN, post 2000, suggest reductions in nutrient inputs as a result of EU " }, { "children": [ { "text": "policy implementation" } ], "type": "strong" }, { "text": ". Decreasing trends have become less common for DIP after 2000, with increasing trends observed in both the Baltic and Black Seas (11% each). This rise in DIP concentrations is likely due to phosphorus release from sediment under anoxic conditions" }, { "children": [ { "text": "" } ], "data": { "footnote": "<?xml version=\"1.0\"?>\n<div class=\"csl-bib-body\" style=\"line-height: 1.35; \">\n <div class=\"csl-entry\">Stigebrandt, A. and Andersson, A., 2020, 'The Eutrophication of the Baltic Sea has been Boosted and Perpetuated by a Major Internal Phosphorus Source', <i>Frontiers in Marine Science</i> 7 (https://www.frontiersin.org/articles/10.3389/fmars.2020.572994/full).</div>\n</div>\n", "footnoteTitle": "Stigebrandt, Anders, November, 2020, The Eutrophication of the Baltic Sea has, Frontiers in Marine Science", "uid": "UmqQk", "zoteroId": "9FPGG5JU" }, "type": "zotero" }, { "text": ". 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The main difference between the two periods is the increased available datasets post 2000. The number of assessment areas recording significant decreasing trends in dissolved inorganic nitrogen levels (DIN) of the Baltic and Greater North Seas is greater than the number recording increasing trends.", "value": [ { "children": [ { "text": "The distribution of nutrient trends in European waters (Figure 1) displays data from 1980 to 2023, divided into two periods: pre and post year 2000. The main difference between the two periods is the increased available datasets post 2000. The number of assessment areas recording significant " }, { "children": [ { "text": "decreasing trends" } ], "type": "strong" }, { "text": " in dissolved inorganic nitrogen levels (DIN) of the Baltic and Greater North Seas is greater than the number recording increasing trends. " } ], "type": "p" } ] }, "24106a53-f270-426b-8b97-4b50380e8339": { "@type": "slate", "plaintext": "Eutrophication in marine, coastal and estuarine ecosystems is a consequence of anthropogenic nutrient over-enrichment , with nitrogen and phosphorus coming from land-based sources and marine activities . The excessive availability of nitrogen and phosphorus accelerates growth of microalgae and higher forms of plant life, with indirect negative effects on aquatic organisms and water quality. Eutrophication impacts marine organisms by reducing light availability and water quality, decreasing oxygen.", "value": [ { "children": [ { "text": "Eutrophication in marine, coastal and estuarine ecosystems is a consequence of anthropogenic nutrient " }, { "children": [ { "text": "over-enrichment" } ], "type": "strong" }, { "text": ", with nitrogen and phosphorus coming from land-based sources and marine activities" }, { "children": [ { "text": "" } ], "data": { "footnote": "<?xml version=\"1.0\"?>\n<div class=\"csl-bib-body\" style=\"line-height: 1.35; \">\n <div class=\"csl-entry\">EEA, 2019, 'Nutrient enrichment and eutrophication in Europe&#x2019;s seas &#x2014; European Environment Agency', (https://www.eea.europa.eu/publications/nutrient-enrichment-and-eutrophication-in) accessed May 12, 2022.</div>\n</div>\n", "footnoteTitle": "EEA, 2019, Nutrient enrichment and eutrophication i", "uid": "ik5cn", "zoteroId": "Y2VDHS2J" }, "type": "zotero" }, { "text": ". The excessive availability of nitrogen and phosphorus accelerates growth of microalgae and higher forms of plant life, with indirect negative effects on aquatic organisms and water quality. Eutrophication impacts marine organisms by reducing light availability and water quality, decreasing oxygen. " } ], "type": "p" } ] }, "372dd159-ec8e-4bc9-b999-aaa7a0c2846a": { "@type": "slate", "plaintext": "See more information about relevant legislation in the Supporting information.", "value": [ { "children": [ { "text": "See more information about relevant legislation in the Supporting information." } ], "type": "p" } ] }, "4f19e827-45e2-4997-8a15-daa5bfba150a": { "@type": "slate", "plaintext": "For orthophosphate (DIP), the number of assessment areas recording significant increases is greater than the recorded decreasing trends in the Baltic and Black Seas. The Greater North Sea has a significant decreasing trend. Due to limited time series data, many areas cannot be assessed, or trends for both DIN and DIP cannot be identified.", "value": [ { "children": [ { "text": "For orthophosphate (DIP), the number of assessment areas recording significant " }, { "children": [ { "text": "increases" } ], "type": "strong" }, { "text": " is greater than the recorded decreasing trends in the Baltic and Black Seas. The Greater North Sea has a significant decreasing trend. Due to limited time series data, many areas cannot be assessed, or trends for both DIN and DIP cannot be identified. " } ], "type": "p" } ] }, "5970fadd-f4d7-4fe2-a402-c0805666105f": { "@type": "group", "className": "figure-metadata", "data": { "blocks": { "f6cb9b54-f335-4ff2-8e94-28b883364599": { "@type": "slate", "plaintext": "Figure 1. Trends in dissolved inorganic nitrogen and orthophosphate concentrations in transitional, coastal and marine waters in Europe, for two periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)", "value": [ { "children": [ { "text": "Figure 1. Trends in dissolved inorganic nitrogen and orthophosphate concentrations in transitional, coastal and marine waters in Europe, for two periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)" } ], "type": "h3-light" } ] } }, "blocks_layout": { "items": [ "f6cb9b54-f335-4ff2-8e94-28b883364599" ] } }, "id": "figure-metadata-b0279dde-1ceb-4137-a7f1-5ab7b46a782c", "styles": {}, "variation": "default" }, "7a71ec84-47bb-463a-8fe4-18de9b9220f9": { "@type": "slate", "plaintext": "These results show significant decreasing trends in the levels of nutrients in regional seas and areas where nutrient management strategies have been implemented. However, phosphorus concentrations still increase in some regions (e.g. Baltic Sea). Main sources of phosphorus are\u00a0agricultural fertilisers, manure, and organic wastes in sewage and industrial discharges. More effort is required to lower these emissions to waters.", "value": [ { "children": [ { "text": "These results show significant decreasing trends in the levels of nutrients in regional seas and areas where nutrient " }, { "children": [ { "text": "management strategies" } ], "type": "strong" }, { "text": " have been implemented. However, phosphorus concentrations still increase in some regions (e.g. Baltic Sea). Main sources of phosphorus are\u00a0agricultural fertilisers, manure, and organic wastes in sewage and industrial discharges. More effort is required to lower these emissions to waters. " } ], "type": "p" } ] }, "b0279dde-1ceb-4137-a7f1-5ab7b46a782c": { "@type": "embed_content", "disableNewBlocks": true, "fixed": true, "instructions": { "content-type": "text/html", "data": "<p>figure instructions goes here</p>", "encoding": "utf8" }, "readOnlySettings": true, "required": true, "url": "../../../../resolveuid/7195b5cbae924d05a48b71107026524c" }, "deb7e84d-d2c8-4491-90fa-3dc65fe02143": { "@type": "slate", "fixed": true, "instructions": { "content-type": "text/html", "data": "<p><br/></p>", "encoding": "utf8" }, "plaintext": "", "readOnlySettings": true, "required": true, "value": [ { "children": [ { "text": "" } ], "type": "p" } ] }, "e3ecb62a-7d38-4518-9371-44f57406a088": { "@type": "slate", "plaintext": "Emissions of nutrients on land originate from urban areas, dispersed settlements, industrial areas, farms, and agricultural practices. Sea-based sources include aquaculture, dumping of dredged material and discharge from ships. All emissions of nutrients to air contribute to atmospheric deposition and transboundary pollution. Eutrophication is still a significant problem in the Baltic, Black and Greater North Seas and in some parts of the Mediterranean Sea ( WISE Marine ).", "value": [ { "children": [ { "text": "Emissions of nutrients on land " }, { "children": [ { "text": "originate from" } ], "type": "strong" }, { "text": " urban areas, dispersed settlements, industrial areas, farms, and agricultural practices. Sea-based sources include aquaculture, dumping of dredged material and discharge from ships. All emissions of nutrients to air " }, { "children": [ { "text": "contribute to" } ], "type": "strong" }, { "text": " atmospheric deposition and transboundary pollution. Eutrophication is still a significant problem in the Baltic, Black and Greater North Seas and in some parts of the Mediterranean Sea (" }, { "children": [ { "text": "WISE Marine" } ], "data": { "url": "https://water.europa.eu/marine/data-maps-and-tools/msfd-reporting-information-products/ges-assessment-dashboards/ges-marine_waters" }, "type": "link" }, { "text": "). " } ], "type": "p" } ] }, "43df8fab-b278-4b0e-a62c-ce6b8e0a881d": { "@type": "dividerBlock", "section": false, "short": true, "disableNewBlocks": true, "fixed": true, "hidden": true, "readOnly": true, "required": true, "styles": {}, "spacing": "m", "fitted": false } }, "blocks_layout": { "items": [ "5970fadd-f4d7-4fe2-a402-c0805666105f", "b0279dde-1ceb-4137-a7f1-5ab7b46a782c", "43df8fab-b278-4b0e-a62c-ce6b8e0a881d", "24106a53-f270-426b-8b97-4b50380e8339", "e3ecb62a-7d38-4518-9371-44f57406a088", "0e34daa3-471b-4c02-ae02-961564842566", "4f19e827-45e2-4997-8a15-daa5bfba150a", "7a71ec84-47bb-463a-8fe4-18de9b9220f9", "372dd159-ec8e-4bc9-b999-aaa7a0c2846a" ] } }, "disableInnerButtons": true, "disableNewBlocks": false, "fixed": true, "ignoreSpaces": true, "instructions": { "content-type": "text/html", "data": "<p><strong>Assessment text remains at</strong> <strong>the relevant</strong> <strong>aggregate level</strong> <strong>(i.e.</strong> <strong>global, EU, sectoral)</strong> <strong>and addresses the following: </strong></p><ol keys=\"dkvn8,e367c,f4lpb,9j981,7ai6k,3g3pd\" depth=\"0\"><li>Explains in one or two sentences on the environmental rationale of the indicator, i.e. why it matters to the environment that we see an increase/decrease in the value measured.</li><li>Explains in one or two sentences the associated policy objective, which can be either quantitative or directional. More information on the policy objective and related references will be included in the supporting information section. Where there is no policy objective associated with the indicator, i.e. where the indicator addresses an issue that is important for future policy formulation, this text should explain instead why this issue is important.</li><li>IF NECESSARY - Explains any mismatch between what the indicator tracks and what the policy objective/issue is.</li><li>Qualifies the historical trend (e.g. steady increase) and explains the key reasons (e.g. policies) behind it. If there is a quantitative target it explains if we are on track to meet it.</li><li>IF NECESSARY - Explains any recent changes to the trend and why.</li><li>IF NECESSARY - Describes what needs to happen to see adequate progress in future, for instance in order to remain on track to meet targets.</li></ol><p><strong>Please cite your work if</strong> <strong>necessary</strong> <strong>using the EEA citation style (i.e.</strong> <strong>EEA, 2020). A full reference list appears in the supporting information section.</strong></p>", "encoding": "utf8" }, "maxChars": "2000", "placeholder": "Aggregate level assessment e.g. progress at global, EU level..", "readOnlySettings": true, "required": true, "title": "Aggregate level assessment" }, "e9736b7c-4902-48aa-aecd-b706409a576d": { "@type": "dividerBlock", "disableNewBlocks": true, "fixed": true, "hidden": true, "readOnly": true, "required": true, "section": false, "spacing": "m", "styles": {} } }
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Supporting information
Methodology [ { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "The primary data source for this indicator is the OceanCSI_1980 - 2023 dataset (ICES 2023), which compiles information from ICES, EMODnet, and the WISE SoE \u2013 Water Quality (WISE-6). The data handling processes\u2014extraction, selection, aggregation, trend analysis and plotting\u2014are performed using the R programming language. " } ], "type": "p" }, { "type": "p", "children": [ { "text": "" } ] }, { "children": [ { "text": "Data flagged as bad quality (bad value, probably bad value), uncertain quality (value in excess, uncertain value, missing value), or duplicates are excluded, and the 99.9% percentile of the highest values are sorted out. The analysis considers only data from depths of less than 10 meters and during the winter months, which include January to March for stations in the Baltic Sea east of 15E and January to February for all other stations. " } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "Average values are calculated using a combination of estimated marginal means (EMM) and arithmetic means, where the EMM were used for time series containing data from both different years and months and the arithmetic means were used for time-series with yearly observations. Initial calculations of average annual concentrations are done by location and by month-year to standardise observations across different depths and time (days, hours or even minutes in some cases). " } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "" }, { "children": [ { "text": "Geographical classification: sea region, coastal or offshore and station " } ], "type": "strong" }, { "text": "" } ], "type": "p" }, { "children": [ { "text": "" } ], "type": "p" }, { "children": [ { "text": "Stations are geographically defined by their longitude and latitude in decimal degrees. All geographical positions in the data are mapped to a marine (sub) region based on coordinates. The data often lack reliable and consistent station identifiers, which can lead to fragmented time series. To improve time series aggregation, data are grouped into 1.375km squares for coastal stations (within 20km of the coastline) and 5.5km squares for open water stations. While this procedure does not eliminate the risk of incorrect data aggregation or the breaking of time series due to minor positional shifts, it significantly reduces these issues. These aggregated clusters are designated as \u2018locations\u2019. " } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "EEA grid used\u00a0" }, { "children": [ { "text": "https://www.eea.europa.eu/en/datahub/datahubitem-view/a35e113a-fe10-4e20-9c49-7dc5b47b16b5?activeAccordion=1083504" } ], "data": { "url": "https://www.eea.europa.eu/en/datahub/datahubitem-view/a35e113a-fe10-4e20-9c49-7dc5b47b16b5?activeAccordion=1083504" }, "type": "link" }, { "text": ". " } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "h3" }, { "children": [ { "text": "" }, { "children": [ { "text": "Trend analysis" } ], "type": "strong" }, { "text": "" }, { "children": [ { "text": "" } ], "type": "strong" }, { "text": "" } ], "type": "p" }, { "children": [ { "text": "Temporal trends are analysed based on the yearly averages for each time-series within a grid cell. A linear regression model (lm) is then applied to identify trends over time, with the slope indicating whether the trend is positive or negative. To assess statistical significance (p.value < 0.05), a robustness test is conducted. Additionally, the Mann-Kendall test is used to validate the trends. Based on the Mann-Kendall results, trends are classified as \"increasing,\" \"decreasing,\" or \"no trend.\" If the initial test deems a model \"not robust,\" the trend is automatically set to \"no trend.\" Only stations with at least five years of data are included in the analysis. " } ], "type": "p" } ]
Data sources and providers { "readOnly": true, "data": [ { "@id": "ea361663-75c6-4e23-81de-6020fd8dff24", "link": "https://www.ices.dk/data/data-portals/Pages/ocean.aspx", "organisation": "International Council for the Exploration of the Sea (ICES)", "title": "Oceanographic database" }, { "@id": "88957d05-08b6-46e5-958a-0d5e5620c20e", "link": "https://cdi-chemistry.seadatanet.org/search", "organisation": "European Marine Observation and Data Network (EMODnet)", "title": "Chemistry data - Data & products on marine water quality" }, { "@id": "1ffa1f3d-7ec4-40de-8e16-f0c8bb108526", "link": "https://www.eea.europa.eu/en/datahub/datahubitem-view/fbf3717c-cd7b-4785-933a-d0cf510542e1?activeAccordion=1092907", "organisation": "European Environment Agency (EEA)", "title": "Waterbase - Water Quality ICM, 2023" }, { "@id": "3a89eb9d-1f7e-475d-bdc0-badebe2b668e", "title": "Regional seas around Europe - version 2, Oct. 2022", "link": "https://www.eea.europa.eu/en/datahub/datahubitem-view/d09a1d82-8e11-4448-85a5-e2613aeccf57?activeAccordion=1083843", "organisation": "European Environment Agency (EEA)" } ] }
Definition [ { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "This indicator shows the geographical distribution and trends in winter concentrations of DIN (sum of ammonium, nitrite and nitrate) and DIP (orthophosphate), (\u00b5mol/l) in the upper 10 meters of the water column during the assessment period 1980-2023, in Europe\u2019 seas. The purpose of this indicator is to illustrate the effectiveness of regulatory measures aimed at reducing nutrient discharges and their impact on phytoplankton levels. " } ], "type": "p" } ]
Unit of measure [ { "children": [ { "text": "The trends have no units; Number of time series (entire numbers)" } ], "type": "p" } ]
Policy / environmental relevance [ { "type": "p", "children": [ { "text": "The risk of eutrophication and the goal of achieving good status for coastal and marine waters are addressed by the\u00a0" }, { "type": "link", "data": { "url": "https://eur-lex.europa.eu/eli/dir/2000/60/ojhttps://eur-lex.europa.eu/eli/dir/2000/60/oj" }, "children": [ { "text": "Water Framework Directive (WFD) " } ] }, { "text": "and the " }, { "type": "link", "data": { "url": "https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32008L0056" }, "children": [ { "text": "Marine Strategy Framework Directive (MSFD)" } ] }, { "text": ". " } ] }, { "type": "p", "children": [ { "text": "" } ] }, { "type": "p", "children": [ { "text": "The Comission Decision (EU) 2017/848" }, { "children": [ { "text": "" } ], "data": { "extra": [], "footnote": "<?xml version=\"1.0\"?>\n<div class=\"csl-bib-body\" style=\"line-height: 1.35; \">\n <div class=\"csl-entry\">Commission Decision (EU) 2017/848 of 17 May 2017 laying down criteria and methodological standards on good environmental status of marine waters and specifications and standardised methods for monitoring and assessment, and repealing Decision 2010/477/EU (Text with EEA relevance. ), 2017, OJ L.</div>\n</div>\n", "footnoteTitle": " Commission Decision (EU) 2017/848 of 17 May 2017 laying down criteria and methodological standards on good environmental status of marine waters and specifications and standardised methods for monitoring and assessment, and repealing Decision 2010/477/EU (Text with EEA relevance. )", "uid": "DZRW3", "zoteroId": "7E8MY5FG" }, "type": "zotero" }, { "text": ", developed under the MSFD Common Implementation Strategy (CIS), outlines key elements for assessing eutrophication under Descriptor 5. The primary criterion (D5C1) focuses on nutrient concentrations. The related objective is: " }, { "children": [ { "text": "Nutrient concentrations are not at levels that indicate adverse effects of eutrophication. " } ], "type": "em" }, { "text": "Threshold values should be set to assure Good Environmental Status (GES) and be harmonised with the WFD." } ] }, { "children": [ { "text": "" } ], "type": "p" }, { "type": "p", "children": [ { "text": "" }, { "children": [ { "text": "Commission Decision (EU) 2018/229" } ], "data": { "footnote": "<?xml version=\"1.0\"?>\n<div class=\"csl-bib-body\" style=\"line-height: 1.35; \">\n <div class=\"csl-entry\">Commission Decision (EU) 2018/229 of 12 February 2018 establishing, pursuant to Directive 2000/60/EC of the European Parliament and of the Council, the values of the Member State monitoring system classifications as a result of the intercalibration exercise and repealing Commission Decision 2013/480/EU (notified under document C(2018) 696)Text with EEA relevance., 2018, OJ L.</div>\n</div>\n", "footnoteTitle": " Commission Decision (EU) 2018/229 of 12 February 2018 establishing, pursuant to Directive 2000/60/EC of the European Parliament and of the Council, the values of the Member State monitoring system classifications as a result of the intercalibration exercise and repealing Commission Decision 2013/480/EU (notified under document C(2018) 696)Text with EEA relevance.", "uid": "GZFZ5", "zoteroId": "9UIJZTAU" }, "type": "zotero" }, { "text": " summarises the results of the third phase of the WFD intercalibration exercise, providing different threshold values for chlorophyll-a depending on the regional sea and water typology (EU, 2018). Nevertheless, threshold values and indicators are different for different regions, depeding on water typologies. Threshold values, indicators and classification systems are currently still hard to be used in an assessment on the pan-European scale. Several EU directives such as the " }, { "children": [ { "text": "Nitrates Directive" } ], "data": { "url": "https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex:31991L0676" }, "type": "link" }, { "text": " and the " }, { "children": [ { "text": "Urban Waste Water Treatment Directive" } ], "data": { "url": "https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex%3A31991L0271" }, "type": "link" }, { "text": " are directly addressing human activities and are aiming to reduce the loads of nutrients emitted in aquatic systems. " } ] }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "The" }, { "children": [ { "text": "\u00a0EU Biodiversity Strategy to 2030" } ], "data": { "url": "https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex%3A52020DC0380" }, "type": "link" }, { "text": ",\u00a0" }, { "children": [ { "text": "Farm to Fork" } ], "data": { "url": "https://food.ec.europa.eu/horizontal-topics/farm-fork-strategy_en" }, "type": "link" }, { "text": "\u00a0and\u00a0" }, { "children": [ { "text": "Zero Pollution Action Plan " } ], "data": { "url": "https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A52021DC0400&qid=1623311742827" }, "type": "link" }, { "text": "are the main policies under the\u00a0" }, { "children": [ { "text": "EU Green Deal\u00a0" } ], "data": { "url": "https://commission.europa.eu/strategy-and-policy/priorities-2019-2024/european-green-deal/protecting-environment-and-oceans-green-deal_en" }, "type": "link" }, { "text": "setting ambitious targets for the reduction of nutrients from agriculture. " } ], "type": "p" }, { "children": [ { "text": "" } ], "type": "p" }, { "children": [ { "text": "In addition, international initiatives and policies such as the Regional Sea Conventions \u2014 the " }, { "children": [ { "text": "Oslo-Paris Convention (OSPAR)" } ], "data": { "url": "https://www.ospar.org/" }, "type": "link" }, { "text": ", the " }, { "children": [ { "text": "Helsinki Convention (Helcom)" } ], "data": { "url": "https://helcom.fi/" }, "type": "link" }, { "text": ", the " }, { "children": [ { "text": "Barcelona Convention (UNEP-MAP)" } ], "data": { "url": "https://www.unep.org/unepmap/" }, "type": "link" }, { "text": " and the " }, { "children": [ { "text": "Black Sea Convention" } ], "data": { "url": "https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX%3A52001DC0615%3AEN%3AHTML" }, "type": "link" }, { "text": " \u2014 also outline measures that aim to reduce the loads and impacts of nutrients and include countries beyond the EU." } ], "type": "p" }, { "children": [ { "text": "" } ], "type": "p" }, { "children": [ { "text": "This indicator assesses trends in nutrient levels in European transitional, coastal and marine waters to provide an indication of whether measures taken to reduce the risk of eutrophication are on track to be effective. It does not provide information on whether or not policy objectives have been achieved, as threshold values (boundaries between good and bad condition) were not available for each location." } ], "type": "p" } ]
Frequency of dissemination 1
Accuracy and uncertainties [ { "type": "p", "children": [ { "text": " No uncertainties have been quantified. The data availability is variable across the different regional seas, with higher data coverage over space and time in the North Sea and the Baltic Sea. Hence, the accuracy of the assessment is more precise for those regions. All observations have been gathered from large databases with differences between methods for sampling and analysing which cannot be identified or quantified but may influence the results in some areas. The databases are also known to include faulty data, which slips though the first data cleaning process, therefore a second cleaning was performed by removing the 99.9 % percentile of the highest values in each region. The risk of removing potential correct data by this extra cleaning was estimated to be very low and would to have negligible effect on the assessment, as the number of excluded data was very low compared to the total number of observations, and the extreme values and potential faulty observations were sorted out which could have had a potential effect on the assessment. " } ] }, { "children": [ { "text": "" } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "" }, { "children": [ { "text": "Geographical comparability " } ], "type": "strong" }, { "text": "" } ], "type": "p" }, { "children": [ { "text": "The natural ranges of nutrient values vary greatly depending on the geographical characteristics of monitored locations. Nutrient concentrations tend to be higher in coastal waters due to river discharges and direct nutrient inputs. Thus, geographical comparisons of results should be made only within regional seas and between similar water types (i.e. transitional, coastal, or offshore locations). " } ], "type": "p" }, { "children": [ { "text": " " } ], "type": "p" }, { "children": [ { "text": "" }, { "children": [ { "text": "Comparability over time" } ], "type": "b" }, { "text": " " } ], "type": "p" }, { "type": "p", "children": [ { "text": " The natural ranges of nutrient values also vary greatly depending on the season. However, as assessments have been made on a yearly basis and only for winter months (January to March for Baltic Sea stations east of 15E and January to February for all other stations), temporal comparability is possible. It is also important to note that the temporal range of data at different locations varies depending on the availability of data, although all locations have at least five-yearly observations. " } ] } ]
Settings
Short name nutrients-in-transitional-coastal-and
Versioning enabled yes
Contents
Number of time series available showing increasing, decreasing or no trends in dissolved inorganic nitrogen and orthophosphate concentrations for each regional sea for two time periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)

The different sea regions are presented by one bar each. The numbers corresponds to the number of grid cells (time series) with statistically significant (p<0.05) decreasing trends (green), increasing trends (orange) and no trends (grey) for two time periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023). P is a statistical term describing the probability that the trend is significant.

Trends in dissolved inorganic nitrogen and orthophosphate concentrations in transitional, coastal and marine waters in Europe, for two periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023)

Trends in concentrations of nitrogen (dissolved inorganic nitrogen — DIN) and dissolved inorganic phosphorus (DIP, as orthophosphate) in the upper 10m of the water column in European seas during the season of low phytoplankton growth (SLPG) are shown for two periods; Pre 2000 (1980-1999) and Post 2000 (2000-2023). Green grid cells indicate time-series with significant (p<0.05) decreasing trends; orange grids cells show areas with significant (p<0.05) increasing trends; and grey grid cells show areas with no significant trends. In these cases, p is a statistical term describing the probability that the trend is significant.