It is my great pleasure to be given the opportunity to work with Prof. Richard Sanders (@OceanRics), Dr. Daniel Mayor and Ms. Stacey Felgate (@staceyfelgate). As a student at the Nanyang Technological University (NTU) in Singapore, I worked on quantifying dissolved organic matter and how the composition changes along a land-to-ocean continuum. At NOCS, I worked closely with Stacey to investigate the processes that are involved in the removal of dissolved organic matter from rivers to ocean. Some of the processes involved include the breakdown of organic matter by light, microbial activity and sediment flocculation. To further understand the light and microbial processes, we collected samples from the Beaulieu and Conway River for incubation and measured the oxygen concentration present in the samples over a period of time. This allowed us to observe the rate of oxygen depletion or production which can be further attributed to several processes mentioned.

Each air tight vial had a sensor spot at the base and a measurement of the oxygen concentration can be taken using optical fiber technology. The sensor spots give off a colour as a proxy for the oxygen concentration, the optical fibre then reads the sensor spot and provide a measurement for the oxygen concentration. This can be taken at specific time intervals to understand the rate of oxygen depletion.

We went on field trips to the Beaulieu River in the New Forest and the Conway River in Bangor, North of Wales to collect samples for our incubation experiments. Conducting field work in the U.K. is certainly very different as compared to Singapore. Some of my best memories during the internship came from the field trips that we had. In the New Forest, we had a curious donkey snooping around while we collected samples and encountered various animals like horses and cows grazing on massive grasslands. This is not a common sight in Singapore. We found that the Beaulieu River had a very active microbial community that is respiring and consuming oxygen rapidly. Coincidentally, a local once mentioned that there was a pig farm nearby the Beaulieu River and that may be contributing excess nutrients to the river and hence driving primary production and microbial activity in the river.

In the Conway, I was utterly amazed by the landscape at the Snowdonia National Park. We drove through the mountains that were carved and eroded by glaciers in the past, massive hills with a plethora of sheep and lamb. In addition, Stacey taught me to differentiate the scent of sheep milk and decaying cow fecal matter. Samples collected from the Conway River were incubated in NOCS and the rate of oxygen consumption were found to be lower than the Beaulieu River.

Last but not least, having a chance to present to the public audience about our work at the graduate fair at the University of Southampton was a memorable one. At the graduate fair, we communicated the importance of our project to the audience, let members of the public to try our oxygen measurement kit and engaged them to think what should be considered when planning a river expedition.

In the Conway, I was utterly amazed by the landscape at the Snowdonia National Park. We drove through the mountains that were carved and eroded by glaciers in the past, massive hills with a plethora of sheep and lamb. In addition, Stacey taught me to differentiate the scent of sheep milk and decaying cow fecal matter. Samples collected from the Conway River were incubated in NOCS and the rate of oxygen consumption were found to be lower than the Beaulieu River.

Throughout this internship, I found that it is really important to be able to innovate and adapt when faced with unforeseen obstacles. There were several points where we were faced with obstructions. For instance, the oxygen depletion rates in the Beaulieu River were way higher than expected, and thus the first round of the experiment was not successful. However, with this primary understanding, we improved on our experimental procedures and that lead to two successful incubation experiments. There were great memories made and new friendship forged over the past five weeks and being at NOCS was inspiring as I continue to pursue a career in the science field.

The post Guest Blog – Amanda Cheong (Singapore) appeared first on Exploring our Oceans .

Last week, 18 scientists across more 11 countries came together in a sleepy town in Sweden to discuss ways to monitor how much carbon is being transported from land to sea via rivers throughout Europe, and I was pretty excited. Land-ocean carbon transport is my favourite topic (or at least its the subject of my PhD, so may as well be), and it is a luxury to spend days discussing your passion with like-minded people, each at the cutting edge of their field.

After a 5am start and a 7:45am flight out of Heathrow, we flew into Gothenburg Landvetter Airport. As the plane touched down I caught sight of the flat, white world into which we had descended and seriously questioned whether I had packed warm enough clothes. As I stepped out onto the tarmac, face braced for impact with the freezing cold air, I was pleasantly surprised when instead the sun hit my face and I realised it wasn’t so bad after all!  -7 doesn’t feel so cold when the sun shining at the same time.

Two hours and two busses later we arrived in Stenungsund, a little town to the south of Gothenburg, where we awaited our ride in the most charming little diner where we were kept entertained by the chef who appeared to enjoy surprising us with slightly unusual but delicious Swedish fare (Pulled Oomph, anyone?). Our ride arrived and, after a trip to the supermarket for supplies, we headed off towards our destination.

Our cabin sat up a steep drive, so steep in fact that we abandoned our four-wheel drive, snow-tired jeep and trudged up to the door through several feet of fresh snow.  A quick catch-up with the team we had come to meet, and we were back out the door and off on our first adventure. One of the other scientists in our party is in the middle of a year-round study of local waterways, and so we accompanied him out to drill holes in the (thankfully very) frozen lakes which surrounded our cabin.

I thought working at sea was sometimes challenging, but hiking through knee high show to drill a hole through ice you are relying upon to support your weight is something altogether different! I’m assured you get used to it, and quickly learn how to safely navigate these environments, and of course we would never have gone out onto the ice without someone who knew what they were doing, but all the same, it felt a little risky! On return to our cabin we were greeted with dinner (a traditional feast of meatballs, potato gratin and lingonberry sauce) and a catch-up about some projects different members of the group had been involved in across Malaysia and the Falkland Islands before we retired for an early night.

The next day, we woke with the birds, cleaned down our cabin for the next intrepid explorers, and headed off to join the rest of the workshop participants in a small town called Ortagarden. From then, our mornings and evenings were spend discussing and collaborating. Experts had assembled from across multiple disciplines to bring their knowledge carbon cycling in rivers, streams, lakes, estuaries, the coastal zone and the ocean together in hopes of finding a coherent way to monitor the whole picture, and everyone had their chance to present their work. Aside from travel, the best part of this job is the fact that I’m constantly taken out of my comfort zone, and asked to think about and learn about things which don’t quite sit in my area of expertise. Last week certainly did that, working with terrestrial and aquatic scientists who think about the world from a different perspective to us marine scientists – a classic example of this is when one of the lake ecologists showed an OS map of a mountain range and I thought they were showing bathymetric data of a very deep, sprawling lake system. 

During the afternoons, we were taken out into the countryside by our hosts who showed us several sites where measurements take place. 
The highlight, of course, was walking out across another lake – this time much further from shore – to see a frozen-in monitoring station which, under normal circumstances, we would have been taken to by boat. (If you want to see – and hear – what hiking across a frozen lake looks like, you can see a short film clip here!). Another was the beauty of the planted spruce forests we walked through, and how similar they were to the ones I grew up around in Scotland. Evenings were spent socialising, getting to know one another, and building relationships which will undoubtedly bring about further collaborations and some excellent science in the future.

We returned to Southampton on Friday evening, tired but enthusiastic about what we had learned and the work still to be done.

The post Spring in Sweden appeared first on Exploring our Oceans .

Tonight’s episode was called ‘Green Seas’, and covered habitats and ecosystems often passed over by documentary makers in favour of more ‘charismatic’ ocean dwellers: seagrass meadows, kelp beds, mangrove forests and algal blooms.

What each of these have in common is that, well, they are green plants.

Green plants photosynthesise, using the pigments which give them their colour to transform light energy into sugars. To do this, they take in carbon dioxide (CO2) from the atmosphere, strip off the carbon atoms, and produce oxygen (O2).

Huge efforts are being made across the globe to reduce the amount of CO2 we are adding to the atmosphere in an effort to slow climate change down. Just telling people to reduce the amount of CO2 they release hasn’t worked, and so we have begun to look for ways to mitigate or ‘cancel out’ some of those emissions too.

Ideas about how we might do this are wide ranging and generally fall into the category of ‘geoengineering’ options, where we use a combination of technology and our understanding of natural systems to manipulate them. Studies have been commissioned to look at whether fertilising the oceans with iron might stimulate increased CO2 uptake by phytoplankton and algae. Carbon Capture and Storage (CCS) plants are now operational and capture CO2 produced by power plants before it enters the atmosphere so it can be condensed then pumped into empty oil wells where it will be stored for tens of thousands of years. Scientists are even looking at the possibility of forming deep-sea lakes whereby CO2 is pumped deep into the ocean and pressure stops it from rising back up again. None of these options is without issue.

I work in a related area of marine science called ‘blue carbon’, which started as a term to distinguish carbon produced and stored in the ocean (blue) from carbon produced and stored on land (green) but has since come to represents a sub-discipline of scientists who look at ways to protect, support and maximise the carbon storage capacity of ocean ecosystems in order to slow the rate of climate change.

To do this, we tend to focus on 3 main habitats (seagrass beds, intertidal saltmarshes and mangrove forests) which we call coastal wetlands. These wetlands cover less than 2% of the ocean by area, but are responsible for around half of the total CO2 taken up by the marine environment (which is 70% of the global total).

You see, although ocean plants take in carbon dioxide much the same way as land plants do, they tend to do it much more effectively, and for much longer. Indeed, an acre of seagrass bed can be around 10 times as effective as an acre of pristine Amazon rainforest when it comes to taking up and storing carbon, and can store carbon for hundreds to thousands of years. Millions, even, if that carbon makes it into the rock cycle.

But whilst the rainforest has international protection measures in place to help protect it, seagrass beds do not and are being lost 4 times as fast. Over half of the world’s coastal wetlands have been lost since the 1960s, and today’s rate of removal (340,000 – 980,000 hectares per year) is equivalent to 20-30% of our total annual carbon emissions.

The destruction of these habitats is generally financially motivated, with destructive fishing practices and coastal pollution being the major culprits. Efforts to educate stakeholders and change behaviour patterns have proven relatively unsuccessful, and so we have to try something else. Land-based schemes which put a financial value on forests based upon their ability to store carbon have proven an effective means of habitat conservation in instances where the costs involved in deforestation make it the least profitable option. Perhaps a similar scheme might work for ocean ecosystems?

The thing is, the world’s coastal zones are incredibly dynamic, diverse places which can be much more sensitive to change than their terrestrial counterparts. They are also mostly underwater, which makes them a lot harder to incorporate into trading frameworks than their terrestrial counterparts. For an example, saltmarshes which have been storing carbon for thousands of years can release their entire stash back into the atmosphere in a matter of months if their access to salt water is restricted. And no one wants to invest in something that won’t be there for very long.

That’s where scientists working on blue carbon come in: we are the ones who need to develop new methods to measure carbon storage and to understand how these systems might change over time. It’s not an easy job, but if the Blue Carbon Economy becomes a reality, we’ll have found a way to help ease climate change whilst protecting vulnerable coastal habitats

The Blue Carbon Initiative is an amazing resource for finding out more about Blue Carbon.

The post Blue Planet 2: Green Seas (and Blue Carbon) appeared first on Exploring our Oceans .

 If you watched the Blue Planet II last night I hope you’ll agree that, if all the world’s a stage, the ocean is a pretty spectacular one!

Well, if the organic carbon coming out of rivers was a performer, I think it would be Houdini.

So, just as onlookers could watch Houdini make his way out from the wings and take position centre stage, we can measure the presence of organic carbon and track its movements, allowing us to ‘see’ it flow out of rivers as it makes its grand entrance into the coastal ocean.

And just like Houdini, one minute it’s right in front of us and the next, it’s vanished without a trace. Or has it?

(Before we go any further, if you haven’t read my last blog post, you can catch up here. Caught up? Then let’s go!)

For marine scientists, nothing ever really vanishes. Ever improving scientific techniques and equipment mean that we are continually getting better and better at being able to track the movement of things beyond what you might expect possible. You just need to know what to look for!

At the most basic level, everything is made up of atoms which make up molecules which make up compounds which make up substances which make up, well, everything. So, like every other living thing, the chemicals and compounds which make up microorganisms have to come from somewhere. We use isotopic tracking to find out where…

We think of carbon as being a singular thing, but it actually comes in 3 different forms. These different forms are called isotopes, and they work a bit like smarties (stick with me!)

Say there are two bowls of smarties, one at each end of a hallway – one is mostly blue, with some red and yellow, and the other is mostly yellow, with some blue and red. If you took a handful of smarties from one of the bowls and walked into another room, I could likely tell which bowl you had taken your smarties from (or which end of the hallway you were at when you picked them up), based on the mix of smarties you had in your hand.

If a plant grows on land, it will pick up a different ‘handful of smarties’ compared to one that grows in the ocean. This is that plants isotopic signature, and it’s like a chemical fingerprint specific to that species and location.

We can take a sample of water from anywhere – a lake, a river, the ocean – and filter everything else out until we are left with just the organic material dissolved in it. From there, we can use a technique called mass spectrometry to determine what that material is made up of. Using this technique, we can separate molecules based on their mass, including 3 different forms of carbon. It’s our way of looking to see what smarties the plant is holding – or the isotopic signature of the organic carbon in the sample, which gives us the fingerprint of where it came from.

And this is how we know that riverine organic carbon is going missing – when we look at samples from rivers, we find an isotopic fingerprint full of land-derived organic carbon,  but when we look at samples from the ocean, we find much, much less.

Still with me? Great!

In my next posts, I’ll talk about some of the leading theories around why we don’t find as much riverine organic carbon in the ocean as we expect to, and how my research is trying to understand where it is going. In the meantime, if you have any questions please ask!

The post The ‘Missing’ Carbon Conundrum… Part 2 appeared first on Exploring our Oceans .

Imagine you have some fish in a tank, and you feed them a mixture of small, easy to digest flakes and larger, more difficult to digest flakes. Assuming you feed enough of each type of food to satisfy their hunger, what would you expect to happen?

You’d expect the fish to take the easy option and eat the smaller, easier to digest flakes, whilst the larger, more difficult to digest flakes are mostly left to sink out and end up on the bottom of the tank, right?

Well, that’s basically what happens in coastal waters when microorganisms have a choice between different kinds of food – they pick the easiest option.  

(Let’s just say that anything which is alive and so small you need a microscope to see it is a microorganism, for anyone who wasn’t sure. And because we are scientists and have to be careful with the meaning of words, when we talk about microorganisms we’ll say that they metabolise (or break down) organic matter rather than saying that they digest food, and we’ll use labile and recalcitrant instead of easy to break down and difficult to break down. Don’t worry, you’ll get the hang of it!)

So, coastal waters tend to be incredibly productive places. The surface waters in these regions are teeming with life, and the phytoplankton and algae which live there turn light and carbon dioxide into lovely, fresh, labile organic matter for other organisms to enjoy.  

At the same time tho, huge amounts of recalcitrant organic matter, mostly produced by land plants, flows out of the rivers that feed into these coastal waters. A lot of this river material is old, having been broken down and recycled by river microorganisms so many times as it travels downstream that it has become nutrient deplete and extremely difficult to metabolise by the time it reaches the sea.

With plenty of fresh food being produced in the surface waters, coastal microorganisms don’t need to spend precious energy breaking down this old river material. So what happens to it? Does it sink out and end up on the bottom, just like the fish food did?

No – and that’s the mystery!

Around 50% of the land-plant-derived organic matter which flows out of rivers and into the ocean goes ‘missing’. It’s not floating around in the water column, it’s not sitting in the sediments, and the scientific literature tells us that microorganisms aren’t eating it. So where does it go? 

This might not seem hugely important at first, but for scientists who study the global carbon cycle, solving this conundrum is vital. You see, a large portion of organic matter is made up of carbon, and we know that carbon is linked to climate. 

So let’s think about it! What could be happening to all that organic matter?  

Some of the biggest scientific breakthroughs have come about because people from different fields of expertise and backgrounds got together and threw around some ideas, so have a go!

In my next blog post, I’ll talk about how we know the organic carbon is going missing. In the mean time, over to you!

The post The ‘Missing’ Carbon Conundrum… Part 1 appeared first on Exploring our Oceans .