H2020Индивидуална стипендия2015–2018

MARIS · Mixotrophy among small marine phytoflagellates – prevalence and impact on prokaryotic communities

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

Период: 2015-05-01 → 2018-02-22
Финансиране от ЕС: 212 195 €
Участници: 1
Схема: MSCA-IF-EF-CAR

Линиите свързват координатора с партньорите.

Накратко на български

Малките морски водорасли се изследват в това, как съчетават фотосинтезата с храненето с бактерии. Това помага да се разбере влиянието им върху бактериалните общности и как околната среда променя начина им на хранене в крайбрежните зони.

Този кратък обзор е генериран от изкуствен интелект

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

Резултати накратко

Mixotrophy among small marine phytoflagellates – prevalence and impact on prokaryotic communities

Unicellular microscopic algae inhabiting the world oceans generate half the oxygen available on the planet and fuel marine food webs. Despite this, we do not understand many aspects of their basic ecology. A clear example is mixotrophy, the ability for micro-algae to combine both photosynthesis and feeding on prey to meet their nutritional needs. Discovered many decades ago for eukaryotic micro-algae, it was considered an anecdotal phenomenon until a series of studies starting around the 1990s revealed that this strategy could have significant ecological relevance. Here we focus on small phytoflagellates (unicellular eukaryotic micro-algae < 20 µm in size that possess filaments or flagella used for motion and/or to capture prey). Mixotrophic small phytoflagellates (abbreviated to MSP) are present in all marine systems where there is light, and are normally very abundant (in the order of thousands in any given drop of seawater). They generally prey on bacteria, and can be a major mortality factor for this group. For example, in the North Atlantic Ocean they have been seen to account for up to 90 % of all bacterial losses, and they generally account for 30 - 60 % in most other tested marine systems. However, most of these studies are based on single measurements and more information is needed on how MSP feeding changes along long and short temporal scales; how much different MSP groups contribute to total bacterial consumption (e.g., green vs red micro-algae groups); and how MSP feeding is influenced by different environmental parameters, such as light or nutrient concentration. In the present study we focused on coastal zones and conducted a field and culture studies to determine: (i) How important is MSP feeding in temperate and polar coastal zones? (ii) Can changes in feeding be observed along short and long space and time scales? (iii) How do different environmental parameters influence MSP feeding? And (iv) How different is the feeding magnitude and regulation for different MSP groups?

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

Цел на проекта

Mixotrophy, i.e. the use of photosynthesis and prey uptake for growth, is increasingly recognized as a major trophic strategy for small (≤ 20 µm) phytoflagellates, which are responsible for a significant fraction of global primary production. In fact, marine primary production in many areas is now thought to be supported by organic P and Fe derived from prey. Despite this, a consistent picture of the overall relevance of bacterivory in open ocean and coastal mixotrophic small phytoflagellates (MSP) is lacking. Additionally, a strict dichotomy between `phytoplankton´ and `zooplankton´ is still overwhelmingly employed in models predicting the flow of matter and energy through marine systems, leading to potentially flawed and misleading predictions on ecosystem productivity and the health of global fisheries. This is especially significant when considering that anticipated environmental changes related to climate change are expected to shift the phototrophy/mixotrophy balance, with largely unknown consequences. The present study will combine culture and field work to 1) determine how shifts in environmental conditions related to e.g. season, influence coastal MSP abundance, identity and bacterivorous impact on the whole prokaryotic community, and on specific prokaryotic groups, such as unicellular cyanobacteria; and 2) analyze the importance and basic regulation of bacterial uptake for understudied coastal MSP. The proposed project excellently fuses the expertise areas of the experienced researcher, Dr. Anderson (bacterivory and predator-prey interactions), with the supervisor, Prof. Hansen (mixotrophic phytoflagellates) and the international collaborators, Prof. Jürgens (protist diversity and microbial food web interactions) and Prof. Scanlan (unicellular cyanobacteria), leading to an optimal exchange of knowledge for a successful project outcome. It will additionally restart and further the promising scientific career of Dr. Anderson after her maternity break.

Оригинален текст от CORDIS (на английски).

Участници

KOBENHAVNS UNIVERSITET · KOBENHAVNКоординаторДания