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Frieda Wenzel
Franziska Seitz

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National Geographic Korea - English ver.

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Diatom makes Human and All Living things Alive!｜National Geographic

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According to the World Wide Fund for Nature, which nominated The Swedish Algae Factory a potential "Climate Solver" earlier this year, if the technology penetrated 30 per cent of the market by 2027, global greenhouse emissions could be reduced by 21 million tons of CO2 annually - equivalent to just under four and a half million petrol cars being driven for a year.

Allert's fascination with algae began as a biotechnology undergraduate. Before long, however, she realised that her future lay not in doing research, but in translating innovation into marketable reality. "I had such frustration that there were so many good ideas that really could benefit society that never came out on the market and ended up just being research," she explains. "So there was a real gap there, and I wanted to be part of that gap."

A Masters at Chalmers School of Entrepreneurship followed and it was there she met Angela Wulff, professor of marine ecology at Gothenburg University, who introduced Allert to a species of diatom able to grow beneath the Arctic ice. Allert was "blown away" and in 2014 The Swedish Algae Factory was born, with Allert appointed CEO at the tender age of 24.

In 2017, the Gothenburg-based startup - which has just four employees, including Allert - received funding from the Swedish Energy Agency. Part of the pitch was the range of uses for diatom shells, which can be used for environmentally-friendly sunscreen, organic absorbents for skincare, fertilisers, and even water treatment, since the algae remove nitrogen and phosphorus from the wastewater of fish farms.

"What we saw was that there were a lot of amazing applications, but someone needs to scale it up and actually provide this material," Allert explains. It's no small task, given that it takes a cultivation area of around 3,000 square metres to produce one ton of shells. But the startup's first commercial facility is currently under construction and aiming to begin producing diatoms for sale to the cosmetics and skincare industry in early 2018.

A third is pencilled in for 2019/20 and from there the company is hoping to spread faster than an algal bloom - by 2030 Allert and her team aim to have no less than 30 factories running across Europe.

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These microscopic glass shells are supercharging solar power

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According to the World Wide Fund for Nature, which nominated The Swedish Algae Factory a potential "Climate Solver" earlier this year, if the technology penetrated 30 per cent of the market by 2027, global greenhouse emissions could be reduced by 21 million tons of CO2 annually - equivalent to just under four and a half million petrol cars being driven for a year.

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Environment | News releases | Research | Science

Diatoms in the world's oceans exhale more oxygen than all the world's rainforests. These tiny drifting algae generate about 20 percent of the oxygen produced on Earth each year, and invisibly recycle gases enveloping our planet.

How diatoms respond to rising carbon dioxide levels is still unknown. A new study by the University of Washington and Seattle's Institute for Systems Biology, published June 15 in Nature Climate Change, finds the genetic ways that a common species of diatom adjusts to sudden and long-term increases in carbon dioxide.

"There are certain genes that respond right away to a change in CO2, but the change in the metabolism doesn't actually happen until you give the diatoms some time to acclimate," said first author Gwenn Hennon, a UW doctoral student in oceanography.

Understanding the genetic machinery for how diatoms respond to rising carbon dioxide due to fossil fuel burning could help predict the future of the world's oceans, and determine what role diatoms may play in Earth's future atmosphere.

Many land plants and other photosynthetic organisms grow faster with more CO2. Surprisingly, Hennon's previous research showed that at typical nutrient levels the diatoms just kick back and relax.

"Instead of using that energy from the CO2 to grow faster, they just stopped harvesting as much energy from light through photosynthesis and carried out less respiration," Hennon said.

The new study shows how and why that happens. Hennon cultivated a common species of diatom in the lab under controlled conditions that mimic common ocean conditions, where diatom growth is limited by the availability of nitrogen. In one scenario, she gradually increased the carbon dioxide over four days. In the other scenario she tended her invisible aquarium dwellers for about a month, allowing about 15 generations of diatoms to adjust to CO2 levels as high as 800 parts per million, which Earth's atmosphere could reach by 2100.

When the CO2 suddenly spikes, as might happen during a sudden change in ocean currents, these diatoms produce a signaling molecule that triggers a molecular cascade of events, reducing the energy-intensive processes required to concentrate the carbon dioxide.

The main enzyme for photosynthesis first evolved during the Precambrian period, almost 3 billion years ago, when CO2 was extremely high, at several thousand parts per million.

"There hasn't been another enzyme to replace it since, so plants and algae that photosynthesize have an enzyme that functions better at a higher CO2 level than we currently have," Hennon said.

When the CO2 remains high for a long time, however, the diatoms make a more radical metabolic shift. They decrease photosynthesis and respiration to balance the cell's energy budget. In other words, the diatoms use less energy to grow at the same rate. Diatoms could use the existing light energy to grow faster, but only if there are no other limitations on their growth.

"It really depends on where it is," Hennon said. "There are a lot of situations in the oceans where the diatoms can't grow faster, because they're limited by nutrients such as iron or nitrogen."

Senior author Ginger Armbrust, a UW professor of oceanography, sequenced the full genome of the Thalassiosira pseudonana diatom used in this study in 2004. The new paper builds on that work, as well as the growing genetic knowledge of other diatoms.

"We leveraged results from nearly 100 different publicly available experiments to identify these genetic 'needles in a haystack' and gain our first hints as to how diatoms detect and respond to increasing CO2 concentrations," Armbrust said.

This same genetic machinery exists in distantly related diatoms, Hennon said, suggesting that the same response could occur in many species that live in the real oceans.

"It's really exciting when you find something in a lab strain that you think you might be able to generalize to other diatoms in the field, and maybe even other phytoplankton," Hennon said.

Future research may look at how the genetic shuffle works for other species and under different environmental conditions, as well as how it ties in with the much slower process of genetic evolution.

"We want to understand how these tiny photosynthetic workhorses will respond to the increasing CO2 concentrations of our future oceans," Armbrust said.

The research was funded by the National Science Foundation and the Gordon and Betty Moore Foundation. Other co-authors are UW undergraduate Ryan Groussman; UW research scientists Chris Berthiaume and Rhonda Morales; Nitin Baliga and Justin Ashworth at the Institute for Systems Biology; and Mónica Orellana, who holds appointments at both institutions.

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For more information, contact Hennon at gwennm@uw.edu and Armbrust at armbrust@uw.edu or 206-616-1783.

Tag(s): College of the Environment * Ginger Armbrust * marine microbiology * School of Oceanography

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Genetic switch lets marine diatoms do less work at higher CO2

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Environment | News releases | Research | Science Diatoms in the world's oceans exhale more oxygen than all the world's rainforests. These tiny drifting algae generate about 20 percent of the oxygen produced on Earth each year, and invisibly recycle gases enveloping our planet. How diatoms respond to rising carbon dioxide levels is still unknown.

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This article was most recently revised and updated by

food chain, in ecology, the sequence of transfers of matter and energy in the form of food from organism to organism. Food chains intertwine locally into a food web because most organisms consume more than one type of animal or plant. Plants, which convert solar energy to food by photosynthesis, are the primary food source. In a predator chain, a plant-eating animal is eaten by a flesh-eating animal. In a parasite chain, a smaller organism consumes part of a larger host and may itself be parasitized by even smaller organisms. In a saprophytic chain, microorganisms live on dead organic matter.

Because energy, in the form of heat, is lost at each step, or trophic level, chains do not normally encompass more than four or five trophic levels. People can increase the total food supply by cutting out one step in the food chain: instead of consuming animals that eat cereal grains, the people themselves consume the grains. Because the food chain is made shorter, the total amount of energy available to the final consumers is increased.

The Editors of Encyclopaedia Britannica Adam Augustyn.

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Food chain, in ecology, the sequence of transfers of matter and energy in the form of food from organism to organism. Food chains intertwine locally into a food web because most organisms consume more than one type of animal or plant. Learn more about food chains in this article.

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Study shows unexpected negative impact by CO2 on important plankton group

While calcifying organisms like oysters and corals have difficulty forming their shells and skeletons in more acidic seawater, diatoms have been considered less susceptible to the effects of ocean acidification - a chemical change triggered by the uptake of carbon dioxide (CO2). The globally widespread tiny diatoms use silica, a compound of silicon, oxygen and hydrogen, as a building material for their shells. That diatoms are nevertheless under threat has now been demonstrated for the first time by researchers from GEOMAR Helmholtz Centre for Ocean Research Kiel, the Institute of Geological and Nuclear Sciences Limited New Zealand and the University of Tasmania in a study published in Nature. For the study, researchers linked an overarching analysis of various data sources with Earth system modeling. The findings provide a new assessment of the global impact of ocean acidification.

As a result of ocean acidification, the silicon shells of diatoms dissolve more slowly. This is not an advantage - it causes diatoms to sink into deeper water layers, before they chemically dissolve and are converted back into silica. Consequently, this nutrient is more efficiently exported to the deep ocean and thus becomes scarcer in the light-flooded surface layer, where it is needed to form new shells. This causes a decline in diatoms, according to the scientists in their recent publication. Diatoms contribute 40 percent of the production of plant biomass in the ocean and are the basis of many marine food webs. They are also the main driver of the biological carbon pump that transports CO2 into the deep ocean for long-term storage.

Dr. Jan Taucher, marine biologist at GEOMAR and first author of the study says: "With an overarching analysis of field experiments and observational data, we wanted to find out how ocean acidification affects diatoms on a global scale. Our current understanding of ecological effects of ocean change is largely based on small-scale experiments, that is, from a particular place at a particular time. These findings can be deceptive if the complexity of the Earth system is not taken into account. Our study uses diatoms as an example to show how small-scale effects can lead to ocean-wide changes with unforeseen and far-reaching consequences for marine ecosystems and matter cycles. Since diatoms are one of the most important plankton groups in the ocean, their decline could lead to a significant shift in the marine food web or even a change for the ocean as a carbon sink."

The meta-analysis examined data from five mesocosm studies from 2010 to 2014, from different ocean regions ranging from Arctic to subtropical waters. Mesocosms are a type of large-volume, oversized test tube in the ocean with a capacity of tens of thousands of liters, in which changes in environmental conditions can be studied in a closed but otherwise natural ecosystem. For this purpose, the water enclosed in the mesocosms was enriched in carbon dioxide to correspond to future scenarios with moderate to high increases in atmospheric CO2 levels. For the present study, the chemical composition of organic material from sediment traps was evaluated as it sank through the water contained in the experimental containers over the course of several weeks of experiments. Combined with measurements from the water column, an accurate picture of biogeochemical processes within the ecosystem emerged.

The findings obtained from the mesocosm studies could be confirmed using global observational data from the open ocean. They show - in line with the results of the meta-analysis - a lower dissolution of the silicon shells at higher seawater acidity. With the resulting data sets, simulations were performed in an Earth system model to assess the ocean-wide consequences of the observed trends.

"Already by the end of this century, we expect a loss of up to ten percent of diatoms. That's immense when you consider how important they are to life in the ocean and to the climate system," Dr. Taucher continued. "However, it is important to think beyond 2100. Climate change will not stop abruptly, and global effects in particular take some time to become clearly visible. Depending on the amount of emissions, our model in the study predicts a loss of up to 27 percent silica in surface waters and an ocean-wide decline in diatoms of up to 26 percent by the year 2200 - more than a quarter of the current population."

This finding of the study is in sharp contrast to the previous state of ocean research, which sees calcifying organisms as losers and diatoms being less affected by ocean acidification. Professor Ulf Riebesell, marine biologist at GEOMAR and head of the mesocosm experiments adds: "This study once again highlights the complexity of the Earth system and the associated difficulty in predicting the consequences of man-made climate change in its entirety. Surprises of this kind remind us again and again of the incalculable risks we run if we do not counteract climate change swiftly and decisively."
Original publication:
Taucher, J., Bach, L.T., J.A., Prowe, A.E.F., Boxhammer, T., Kvale, K., Riebesell, U. (2022): Slower silica dissolution under ocean acidification triggers global diatom decline. Nature, doi: https://doi.org/10.1038/s41586-022-04687-0

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Decline of diatoms due to ocean acidification

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25 May 2022 / Kiel. Diatoms are the most important producers of plant biomass in the ocean and help to transport carbon dioxide (CO2) from the atmosphere into the deep ocean and thus regulate our climate.

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Size reduction of Diatoms in the Wadden Sea

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Size reduction of Diatoms in the Wadden Sea

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Schleichende Miniaturisierung: Die Plankton-Algen im Wattenmeer schrumpfen zusehends, wie eine Langzeitstudie enthüllt. Demnach hat sich das Zellvolumen der Nordsee-Algen in den letzten zehn Jahren um rund 30 Prozent verringert, bei einigen Kieselalgen sogar mehr. Dieser Trend betrifft einen Großteil der Arten und könnte damit Auswirkungen auf Biomasse und Funktion des Phytoplanktons in der Nordsee haben. Als wahrscheinlichste Ursache sehen die Forschenden die Meereserwärmung und möglicherweise einen Rückgang der Nährstoffe.
Das Phytoplankton spielt eine entscheidende Rolle nicht nur als Basis der marinen Nahrungskette, sondern auch für das gesamte Erdsystem. Denn die einzelligen Algen produzieren rund die Hälfte des gesamten Sauerstoffs auf unserem Planeten. Doch Klimawandel und Meeresverschmutzung setzen dieser „grünen Lunge der Meere" zu: Die Erwärmung der Ozeane sorgt für eine Verschiebung der Artenzusammensetzung, die das gesamte Nahrungsnetz der Ozeane beeinflussen und verändern könnte.

Faktor Zellgröße im Blick

Auch am Phytoplankton der Nordsee gehen diese Veränderungen nicht spurlos vorüber, wie nun Helmut Hillebrand von der Universität Oldenburg und seine Kollegen festgestellt haben. Im Rahmen ihrer Langzeitstudie haben sie über 14 Jahre hinweg Planktonproben von 20 Stellen im niedersächsischen Wattenmeer entnommen und sie nach Algenarten und Größe ihrer Zellen ausgewertet.

Grundsätzlich ist die Zellgröße zwar von Art zu Art unterschiedlich. Gleichzeitig ist sie aber in wichtiger Faktor für die Produktivität des Phytoplanktons. „Größere Zellen haben eine höhere maximale Nährstoffaufnahme, fixieren mehr Kohlenstoff und enthalten mehr zellinterne Nährstoffe", erklären die Forschenden. Auch die Schwebfähigkeit, Photosynthese und weitere Merkmale werden durch die Zellgröße bestimmt.

Aus früheren Studien ist jedoch auch bekannt, dass Umweltbedingungen und im Speziellen die Wassertemperaturen die Größe von Planktonzellen beeinflussen. „Bislang haben wir allerdings nur wenige Datensätze dazu, wie sich die Zellgrößen einzelner Arten, aber auch ganzer Lebensgemeinschaften, über längere Zeiträume verändern", erklärt Koautorin Lena Rönn vom Niedersächsischen Landesbetrieb für Wasserwirtschaft, Küsten- und Naturschutz (NLWKN). Ihre Studie schließt diese Lücke nun.

Algenzellen heute rund ein Drittel kleiner

Die Analysen ergaben: In den letzten 14 Jahren sind die meisten Planktonlagen im Wattenmeer messbar geschrumpft. Ihre Größe hat sich in zehn Jahren um rund 33 Prozent verringert. „Eine Zelle, die ursprünglich 1.000 Kubikmikrometer groß war, hätte heute nur noch ein Volumen von rund 670 Kubikmikrometern, beziehungsweise würde heute von einer solchen kleineren Zelle ersetzt", so Hillebrand und seine Kollegen.

Der Trend zur Volumenverringerung zeigte sich bei der Mehrheit der untersuchten Algenarten: „Wir konnten die Verkleinerung der Zellgröße bei 63 von 73 untersuchten Spezies nachweisen", berichtet Rönn. „Besonders betroffen waren einzellige Algen mit einem Panzer aus Kieselsäure, die sogenannten Diatomeen." 25 der 27 Arten mit der am stärksten ausgeprägten Zellschrumpfung gehörten zu dieser Gruppe. Dinoflagellaten schienen hingegen weniger anfällig.

Erwärmung ist eine der Ursachen

Der Trend zur Verkleinerung betraf sowohl die einzelnen Individuen einer Art als auch die Zusammensetzung der Populationen als Ganzes. „Das deutet darauf hin, dass de Ursache dieses Schrumpfens tief in allgemeinen Stoffwechselvorgängen verankert ist", erklären Hillebrand und sein Team. Der Volumenrückgang blieb zudem auch dann robust, wenn die Forschenden die saisonalen und jährlichen Schwankungen mitberücksichtigten.

Die Forschenden vermuten, dass die Erwärmung des Meerwassers einer der Treiber dieser Entwicklung ist. Denn dass sich einzellige Arten mit steigenden Temperaturen verkleinern, wurde schon früher beobachtet und vorhergesagt - und das Wattenmeer hat sich messbar erwärmt: „Wir sehen einen Anstieg der Mitteltemperaturen um 2,1 Grad während der 14 Jahre unserer Studie", berichten sie. Zur Erwärmung als Ursache passt zudem, dass die meisten Mikroalgen im Sommer tendenziell kleinere Zellen ausbildeten als im Winter.

Weitere Faktoren wahrscheinlich

Allerdings reicht das allein nicht aus: „Das Ausmaß der Veränderungen in der Zellgröße ist weit größer als nur dadurch erklärbar", schreibt das Team. Modellen zufolge zieht jedes Grad Temperaturanstieg eine Verkleinerung von rund 2,5 Prozent nach sich, übertragen auf das Wattenmeer würde dies eine Schrumpfung von rund fünf Prozent bedeuten. „Wir haben hingegen eine Verringerung um gut 30 Prozent", so Hillebrand und seine Kollegen. Sie vermuten daher, dass weitere Faktoren diesen Trend verstärken. Dazu könnten eine geringere Nährstoffverfügbarkeit gehören oder auch Veränderungen bei der Prädation.

Die Verkleinerung der Algen könnte verschiedene Folgen nach sich ziehen - sowohl für das Phytoplankton wie auch für die Organismen, die sich von ihm ernähren, wie das Team erklärt. Angesichts der großen Bedeutung der Planktonlagen für die marinen Nahrungsketten ist es daher umso wichtiger, diese schleichenden Folge des Klimawandels und weitere Faktoren im Auge zu behalten. (Limnology and Oceanography, 2021; doi: 10.1002/lno.12005)

Quelle: Carl von Ossietzky-Universität Oldenburg

26. Januar 2022

- Nadja Podbregar

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Schleichende Miniaturisierung: Die Plankton-Algen im Wattenmeer schrumpfen zusehends, wie eine Langzeitstudie enthüllt. Demnach hat sich das Zellvolumen der Nordsee-Algen in den letzten zehn Jahren um rund 30 Prozent verringert, bei einigen Kieselalgen sogar mehr. Dieser Trend betrifft einen Großteil der Arten und könnte damit Auswirkungen auf Biomasse und Funktion des Phytoplanktons in der Nordsee haben.

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Author links open overlay panel Richard Gordon ¹

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Diatoms are unicellular, eukaryotic, photosynthetic algae that are found in aquatic environments. Diatoms have enormous ecological importance on this planet and display a diversity of patterns and structures at the nano- to millimetre scale. Diatom nanotechnology, a new interdisciplinary area, has spawned collaborations in biology, biochemistry, biotechnology, physics, chemistry, material science and engineering. We survey diatom nanotechnology since 2005, emphasizing recent advances in diatom biomineralization, biophotonics, photoluminescence, microfluidics, compustat domestication, multiscale porosity, silica sequestering of proteins, detection of trace gases, controlled drug delivery and computer design. Diatoms might become the first organisms for which the gap in our knowledge of the relationship between genotype and phenotype is closed.

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The Glass Menagerie: diatoms for novel applications in nanotechnology

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Author links open overlay panel Richard Gordon Envelope 1 Show more Diatoms are unicellular, eukaryotic, photosynthetic algae that are found in aquatic environments. Diatoms have enormous ecological importance on this planet and display a diversity of patterns and structures at the nano- to millimetre scale.

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How algae survive the harsh world of sea ice

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New research from the University of East Anglia has revealed new clues into how algae survive within polar sea ice.

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How Diatoms Build Their Beautiful Shells

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https://prezi.com/view/UlJ3hjZLcAcTmivYb9bK/

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Diatoms What makes them so important for humans, ecosystems and climate? let's play: tell us anything coming up to your mind, reading this scientific words panel game Introduction enjoying a first impression of diatoms and being introduced to today's process Video source: Structure

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Diatom algae tells a story about climate change

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Diatom algae tells a story about climate change

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Answer the following questions:

1. Where is the project located?
2. What are they studying?
3. What differs diatoms from other algaes?
3. Where are the diatom shells deposited?
4. Why is the arctic a good place for this research?

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Diatom algae populations tell a story about climate change in Greenland - Science Nation

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At Diatoms - What makes them so important for humans, ecosystems and climate?, accessible from https://padlet.com/fsei/ajoyxmtqwhfr6vzl, one of our main priorities is the privacy of our visitors. This Privacy Policy document contains types of information that is collected and recorded by Diatoms - W…

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This are the quiz questions from the Kahoot quiz from the presentation.
You will find the answers on the second page.

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Diatoms: What makes them so importatant?