H2020Индивидуална стипендия2016–2017

DINO_DON · Does vegetation derived organic nitrogen fuel algal blooms in coastal waters of the Baltic Sea?

„Хоризонт 2020“ — Действия „Мария Склодовска-Кюри“

Период: 2016-01-01 → 2017-12-31
Финансиране от ЕС: 191 326 €
Участници: 1
Схема: MSCA-IF-EF-ST

Линиите свързват координатора с партньорите.

Накратко на български

Органичният азот от разлагащата се растителност в Балтийско море се изследва като възможен източник на храна за токсичните водорасли Alexandrium ostenfeldii. Това е важно, защото тези водорасли произвеждат невротоксини, които застрашават здравето на хората и индустрията по отглеждане на миди.

Този кратък обзор е генериран от изкуствен интелект

Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.

Резултати накратко

Does vegetation derived organic nitrogen fuel algal blooms in coastal waters of the Baltic Sea?

Coastal Baltic Sea is heavily affected by eutrophication, a release of nutrient from human activities that has lead to overgrown bays, increased phytoplankton blooms and reduced water transparency. Filamentous annual macrophytes outcompeted bladder wrack (Fucus vesiculosus) and eelgrass (Zostera marina), and the common reed, Phragmites australis has increased in embayments and archipelagos of the Baltic Sea. The annual biomass of macrophytes and reed constitute a major source of organic material to be decomposed during late summer and autumn. The phytoplankton Alexandrium ostenfeldii, a dinoflagellate, produce neurotoxins, saxitoxins and spirolides that can by contaminating seafood cause paralytic shellfish poisoning in humans, with symptoms of acute gastroenteritis, respiratory distress, muscular paralysis, and death. Alexandrium ostenfeldii is also allelopathic and releases a substance that cause cell lysis in co-occurring phytoplankton. This dinoflagellate has been present in the Baltic Sea for a long time but during the last two decades dense blooms have been regularly reported from the coast of Poland to SE Sweden and Finland. In the Föglö archipelago (Åland, Finland), annual blooms of A. ostenfeldii have been reported since 2002. This is of particular concern for the newly established and increasing mussel-farming industry in coastal water of the Baltic Sea. The blooms typically occur when inorganic nutrient concentrations (e.g. nitrate, NO3) are low but dissolved organic nitrogen (DON) is available in high concentrations and in waters overgrown by vegetation. Could organic nutrients, released by the decaying vegetation substitute inorganic nutrients, particularly nitrogen (N), and thus favour the formation of dinoflagellate blooms at times when NO3 is limited? If Baltic Sea A. ostenfeldii is mixotrophic (able to utilize organic nutrients), a trait common among the genus Alexandrium, vegetation or phytoplankton derived DON could drive these blooms. The overall objective of the project is to determine the importance of organic N from various forms of decaying vegetation in the nutrition of bloom forming dinoflagellates.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз

Цел на проекта

Shallow coastal waters in the Baltic Sea, rich in organic matter, are threatened by toxic dinoflagellates blooms, which have deleterious effect on human health and aquatic life. The toxic Alexandrium ostenfeldii blooms in coastal waters where vegetation start to decompose in late summer and release dissolved organic nitrogen (DON). Dinoflagellates are potentially mixotrophic; they are photosynthetic and can use DON. However, the mixotrophic activity for Alexandrium in the Baltic Sea is unknown. The issue will be addressed using stable isotope 15N tracer experiments with enriched substrates from decaying vegetation and visualization of N incorporation pathway (direct uptake or via bacteria) in individual cells using NanoSIMS to determine the mixotrophic capacity of Alexandrium from different geographical sites in the Baltic Sea that differ in vegetation cover and type. A difference in adaptation to N sources may further support the genetic differentiation shown between Alexandrium populations in different areas of the Baltic Sea. The project will provide new understanding to nutritional physiological ecology of toxic dinoflagellates. Our aim is to understand if DON from decaying vegetation can be a source of N for toxic Alexandrium blooms in the Baltic Sea. By matching vegetation and habitat variables with Alexandrium bloom occurrence and mixotrophic activity we will develop a tool to identify potential bloom sites of Alexandrium in shallow coastal waters and to make recommendations for local management. If the application is accepted as IF the training in population genetics and spatial modelling using A. ostenfeldii as a model species, will be a key step for the development of the applicant in light of the research objectives towards modelling how metabolic activity differs with different populations.

Оригинален текст от CORDIS (на английски).

Участници

SUOMEN YMPARISTOKESKUS · HelsinkiКоординаторФинландия