Friday, August 15, 2014

Rising CO2 Levels Will Intensify Phytoplankton Blooms in Eutrophic and Hypertrophic Lakes

Rising CO2 Levels Will Intensify Phytoplankton Blooms in Eutrophic and Hypertrophic Lakes


Harmful algal blooms threaten the water quality of many eutrophic and hypertrophic lakes and cause severe ecological and economic damage worldwide. Dense blooms often deplete the dissolved CO2 concentration and raise pH. Yet, quantitative prediction of the feedbacks between phytoplankton growth, CO2 drawdown and the inorganic carbon chemistry of aquatic ecosystems has received surprisingly little attention. Here, we develop a mathematical model to predict dynamic changes in dissolved inorganic carbon (DIC), pH and alkalinity during phytoplankton bloom development. We tested the model in chemostat experiments with the freshwater cyanobacterium Microcystis aeruginosa at different CO2 levels. The experiments showed that dense blooms sequestered large amounts of atmospheric CO2, not only by their own biomass production but also by inducing a high pH and alkalinity that enhanced the capacity for DIC storage in the system. We used the model to explore how phytoplankton blooms of eutrophic waters will respond to rising CO2 levels. The model predicts that (1) dense phytoplankton blooms in low- and moderately alkaline waters can deplete the dissolved CO2concentration to limiting levels and raise the pH over a relatively wide range of atmospheric CO2conditions, (2) rising atmospheric CO2 levels will enhance phytoplankton blooms in low- and moderately alkaline waters with high nutrient loads, and (3) above some threshold, rising atmospheric CO2 will alleviate phytoplankton blooms from carbon limitation, resulting in less intense CO2 depletion and a lesser increase in pH. Sensitivity analysis indicated that the model predictions were qualitatively robust. Quantitatively, the predictions were sensitive to variation in lake depth, DIC input and CO2 gas transfer across the air-water interface, but relatively robust to variation in the carbon uptake mechanisms of phytoplankton. In total, these findings warn that rising CO2 levels may result in a marked intensification of phytoplankton blooms in eutrophic and hypertrophic waters.

Tuesday, July 15, 2014

Haida Salmon Restoration - Iron Fertilization experiment 2012

Thursday, May 22, 2014

Glacial Melt Pours Iron into Ocean, Seeding Algal Blooms

Glacial Melt Pours Iron into Ocean, Seeding Algal Blooms

The iron fertilizer from glacier melt may help feed plankton blooms that, in turn, suck carbon dioxide out of the sky
glacial melt

A decade ago, a common hypothesis was that rivers and dust supplied the ocean with most of its iron. Since then, scientists have reported in several papers that icebergs and deep-sea hydrothermal vents also may be significant contributors.
Credit: Andrew Bowden via Flickr
Call it natural geoengineering.
Scientists report in a new study this week that glacial melt may be funneling significant amounts of reactive iron into the ocean, where it may counter some of the negative effects of climate change by boosting algal blooms that capture carbon. The paper, published in Nature Communications, adds to a body of research suggesting that melting ice at both poles may have widespread consequences beyond rising sea levels.
"The theory goes that the more iron you add, the more productive these plankton are, and thus the more CO2 is taken out of the atmosphere in photosynthesis," said Jon Hawkings, a doctoral student at the University of Bristol and lead author of the study. "Plankton 'fix' CO2 much like trees."
The work could help improve climate models of the future and fill in data holes about major climate transitions and ice ages in the past, he said. The effects on Antarctica in particular will need additional examination, he said, as iron currently is limited in the Southern Ocean.
Hawkings and a research team from four United Kingdom-based universities tested meltwater collected from the Leverett glacier in Greenland during summer 2012 and detected large amounts of iron nanoparticles known as ferrihydrite. Ferrihydrite is considered to be "bioavailable" iron because it is easily used by plankton in lab experiments, Hawkings said.
Through the detected iron mineral levels in their samples, the team estimated that the flux of bioavailable iron into the ocean from glaciers currently is between 400,000 and 2.5 million metric tons annually from Greenland and up to 100,000 metric tons from Antarctica.
That means that polar regions may rival wind-blown dust as a source of ocean iron. The contribution from Greenland alone could range from 8 to 50 percent of the global ocean flux of bioavailable iron, Hawkings said.
The iron ore counter-effect
A decade ago, a common hypothesis was that rivers and dust supplied the ocean with most of its iron. Since then, scientists have reported in several papers that icebergs and deep-sea hydrothermal vents also may be significant contributors.
A study last year found that a Greenland glacier was releasing iron, but it did not assess as large an area and for as long of a period of time as his study, Hawkings said. The studied area of the Leverett glacier, for instance, is more than 600 kilometers squared, while earlier work assessed a glacier about 5 kilometers squared, he said.
"Our study is the first to date to follow a whole melt season and the first to have looked at a large glacial catchment," he said.
Matt Charette, a senior scientist at the Woods Hole Oceanographic Institution and co-author of an earlier paper on Greenland-supplied iron, said although the new study overlaps somewhat with his prior work, it provides new details.
"A case could be made that a larger system like the one they studied is more appropriate for scaling up to the entire ice sheet," he said.
Kenneth Coale, a scientist at Moss Landing Marine Laboratories, said the paper was "nicely done" and added to understanding of how iron may provide a counter-effect to climate change.
The Greenland iron originates from stored subglacial meltwater that gets "flushed out" by surface waters carried through tunnels and cracks in ice during the melt season, Hawkings said. It's not fully understood how far the iron travels once in the ocean, but it likely stays near both poles. "Evidence exists for transport a few 100 kilometers out to sea, but only limited amounts will reach the open ocean," he said.
It's also not fully understood how the iron will interact with polar ecosystems. Scientists have long known that iron-fueled algae can eat up carbon, leading to speculation that iron fertilization might be a geoengineering option to cool the planet. It also holds the possibility of boosting marine life that feed on plankton. A community in Canada two years ago, for instance, dumped large amounts of iron dust into the ocean to try to boost salmon stocks.
In the case of "natural" iron fertilization via ice sheets, the positive likely outweighs the negative, in the sense that carbon will be removed in an area highly vulnerable to warming, and extra algae may help polar marine life threatened by warming, Hawkings said. He noted that algae can boost krill, which can in turn can feed fish, whales and seals.
However, he pointed to a report from the Woods Hole Oceanographic Institution documenting a range of potential problems with added iron and resulting algae in the ocean in general, such as depleting the ocean surface of other nutrients like nitrogen.
"In theory it's a good thing. However, there may be impacts on species diversity ... and decomposing plankton may use up oxygen in deeper waters, depriving other organisms of it as happens in rivers and lakes when you get an algal bloom," Hawkings said.

Sunday, January 26, 2014

Psychotherapy for Plankton

Psychotherapy for Plankton

The scene: A diatom is out of its oceanic habitat and on a couch, talking to a therapist. The diatom is stressed. It can’t ever seem to get enough nutrients. And it’s feeling underappreciated ... 

Diatom: People just don’t seem to understand. Without me and all the other phytoplankton producing oxygen via photosynthesis, people wouldn’t have half the oxygen they need to breathe!  We’re also the base of the ocean food chain that supports the fish they eat, and all the carbon dioxide I take up from the air to make into my body would still be in the atmosphere, making the earth heat up. Why can’t they see how important I am?
Therapist: I’m hearing that you feel undervalued. Why do you think it is that people don’t understand?
Diatom: I suppose it’s because I’m so small. They can’t see me without a microscope, so I might as well not exist! But that’s not my main problem. I can go on fine without humans knowing how much they depend on me. The thing that’s really getting me down is all this stress I’m under. 
Therapist: Tell me what you mean. What’s causing this stress?
Diatom: Well, it’s a bit of a long story. I’ll start from the beginning. Since I do photosynthesis for a living, sunlight is my energy, and carbon dioxide from the atmosphere is my sustenance. But in order to grow, I need other ingredients, too, like nitrogen, iron, and vitamins. I use these ingredients in a specific ratio, just like a recipe. So, for example, even if there is plenty of nitrogen around in the ocean, unless there is also enough iron, I can’t grow. Whatever runs out first— that’s called a "limiting nutrient."
Therapist: I see. Why this is causing you such stress right now?
Diatom: So, I live in the Southern Ocean around Antarctica. The waters there have plenty of nitrogen for me to use, but there is almost never enough iron to go around. I have to compete with other phytoplankton for my iron, and I also have to compete with bacteria. It’s particularly annoying that I have to share this scarce resource with the bacteria, because the way theyget by in life is only through exploiting the carbon that we phytoplanktonmake for them. It just seems unfair!
Therapist: Correct me if I’m wrong, but it sounds to me like there’s more to this story.
Diatom: Uh, I suppose. My relationship with those bacteria—well, it’s complicated. Even though they take that scarce iron from me when I need it most, I just can’t live without them. When the bacteria grow and die, they release vitamin B12 into the water. I need that B12 to grow. And just like iron, it’s in short supply relative to the other ingredients I need. Without enough of those bacteria growing, I can’t get enough vitamin B12. Without enough iron or B12, I get really stressed! It’s just a bad cycle.
Therapist: It seems almost like sibling rivalry. You and the bacteria are dependent on each other, but at the same time, you’re also competing with each other for iron. That’s quite a delicately balanced relationship you have to negotiate there in the Southern Ocean. What are some strategies you use to try to cope with this stress?
Diatom: Life really gets difficult for me when I start to get starved for iron or vitamin B12. First, I try harder to get these missing nutrients. I make more of proteins that I use to find and transport the iron or vitamin from the seawater into my cell. I also make more of the proteins that I need to move the iron or vitamin around inside my cell. This way, as soon as I find the nutrients I need, I’m ready to use them. 
Therapist:  These seem like good strategies. But what happens if they don’t work?
Diatom: Well, I try to get by with less of whatever I’m feeling starved for. Sometimes I can substitute some other nutrient for the scarce ones, but this doesn’t always work very well. I just can’t work as efficiently when I’m starved, but I can make do and grow more slowly for a while. If supplies of these nutrients are too low, I just won’t survive. You can see why this is causing me such anxiety.
Therapist: Yes, your reaction seems perfectly natural. Let’s try to think of ways to manage this stress.  Are there any ways you could predict what nutrients you are going to be starved for?
Diatom:  Well, I’m not sure. I know that oceanographers are looking into this, too. They want to know what nutrients starve me and the other phytoplankton. But they don’t seem much better than me at predicting which nutrients are limiting how much we can grow. Until a couple of years ago, the scientists weren’t even sure we could be limited by the lack of vitamin B12!
Therapist: That’s interesting. Go on.
Diatom: One way scientists find out about what controls our growth is to take some of us out of the ocean, put us in bottles, add different nutrients, and watch to see which make us grow faster. This doesn’t make a lot of sense to me, because I know that being in a bottle can make us plankton respond to nutrients differently than we do growing in the ocean. There just has to be a better way.
Therapist: Yes, yes. But I’m afraid we are out of time; let’s pick this up again next session.
The following week.
Therapist: I did some research after last week’s session and found something that may help. It seems that some scientists are actually finding new ways to learn about what starves you phytoplankton. Really. The way they are doing this is by looking closely at changes in the way you grow when you are starved for specific nutrients, particularly vitamin B12. They are just learning how to measure those coping strategies you told me about last week. They have developed new technologies that allow them to detect and measure the proteins that organisms make when they are grown under different conditions. 
Diatom: Are you saying that ocean scientists think they can tell when we phytoplankton feel starved for B12 just by watching what kinds of proteins we make? They actually are interested enough in phytoplankton to make new methods to do this?
Therapist: That’s right. When the scientists grew some of you in the laboratory, they noticed that there were a few proteins that you make moreof when you are starved for the vitamin, but not when you are starved for other nutrients. They call these proteins “B12-starvation indicator proteins.” 
Diatom: They come up with fancy names, those scientists. If only they could learn how to measure those—what did they call them, B12 … starvation indicator proteins?—if only they could measure them in the ocean instead of just in the lab! If they did, they could figure out what controls all the patterns and processes that lead to us getting starved for vitamin B12. I’d sure love to know that. Then I could be prepared for the stress.  That would make life so much easier!
Therapist: I know that they are doing their best. In order to use these measurements to learn about what stresses you, the scientists will need to measure these proteins from within a very complex mixture of many thousands or even millions of other proteins in the ocean, and they must also be sure they understand why you make this protein. They are getting closer!
Diatom: Wow, that’s great news. I feel a little better already. It’s comforting to think that those scientists aren’t overlooking me and care so much about me and my stress!
This research was supported by National Science Foundation (NSF) Graduate Research Fellowship and an Environmental Protection Agency STAR Fellowship, the WHOI Ocean Ventures Fund, the NSF Ocean Sciences Division and Office of Polar Programs, and the Gordon and Betty Moore Foundation.
About the author: Erin Bertrand has worked to measure nutrient stress in diatoms in Mak Saito’s lab in the WHOI Marine Chemistry and Geochemistry Department, as part of her research for her Ph.D. from the MIT/ WHOI Joint Program in Oceanography. She  has been interested in how the availability of metals in the environment affects microscopic organisms ever since she started conducting research as an undergraduate at Bates College. When she is not growing diatoms, extracting proteins, taking samples of phytoplankton in Antarctica, or running the mass spectrometer, she likes to hike or run in the woods, listen to live music, or cook something new for her friends and family. Her mentor on this article was Heather Goldstone, a science journalist for WCAI radio (and a graduate of the MIT/WHOI Joint Program).
By Erin Bertrand
MIT/WHOI Joint Program in Oceanography
Marine Chemistry & Geochemistry Dept.

Wednesday, January 22, 2014

Sampath Kumar wins award for Rechargeable Alkaline Zinc Battery

Sampath Kumar wins award for Rechargeable Alkaline Zinc Battery

Technology Refinement and Marketing Programme (TREMAP)
List of Final Stage Selection of Patents for
National Award to Commercializable Patents 2013-14

Sl. No.Patent Title
Name of Patent Holder
Patent Title No.
A nanosized electrochemical dispersion for rechargeable alkaline zinc batteries Sh. Thothathri Sampath Kumar 246506 

Tuesday, December 31, 2013

The Massive Algal Blooms In The Gulf Of Oman Are Stunningly Beautiful From Spac e

The Massive Algal Blooms In The Gulf Of Oman Are Stunningly Beautiful From Space

Several of the world's largest desalination plants sit along the coast of the United Arab Emirates. Every year, they deliver 115 billion gallons of potable water to more than 550,000 people in Dubai alone. But the plants have had to slow or shut down production more frequently over the past decade because of an unexpected disturbance: massive algal blooms in the Gulf of Oman and the Persian Gulf.
The algae, known as red tide, clog pipes and filters at the plants. For warning of an approaching bloom, local authorities now consult data from a European Space Agency project, which began in 2012. When a passing satellite captures an image of an algal bloom (and software scans for the algae's chlorophyll, represented by the intensity of redness), officials alert plant managers, who then have a few days to decide how to adjust water production.

Wednesday, November 13, 2013

Power of Shunya - Times Now, India

Nualgi is featured on The Power of Shunya program on Times Now channel, a promo is available on Youtube - 

The program will be aired on Times Now on November 16th, Saturday at 5.30 pm and November 17th, Sunday at 9.30 am and 6.30 pm.

We will post the link to the full video when it becomes available on Times Now website - 

How can diatom technology clean up our water bodies and provide a lifeline for marine life?