UK Shelf Sea Biogeochemistry Blog

SSB Annual Science Meeting (24-25 Nov 2015) - and other information

2015-09-07T14:19:00.000+01:00

From an email from Phil Williamson covering developments and events relevant to the Shelf Sea Biogeochemistry researchers.

1. Update on SSB cruise series

After a break in June, the SSB cruise series on RRS Discovery resumed in early July with a mostly-pelagic cruise led by Mark Moore (DY 033), followed by the current, mostly-benthic cruise led by Henry Ruhl (DY 034). Excellent progress has been made to date on DY034, with the four main benthic sites already sampled and two SmartBuoy systems successfully recovered. RRS Discovery is due to return to Southampton on 2 September, at the end of what is probably the most intensive and ambitious field campaign ever funded by NERC. It has already delivered a wealth of information, and there is much more to come when data and samples are all fully analysed. Congratulations to all cruise leaders and participants!

2. RRS Discovery in London, 8-10 October 2015

As part of NERC’s 50th anniversary programme, RRS Discovery will be in London (moored alongside HMS Belfast, near Tower Bridge) 8-10 October for both public visits and invitation-only events. Onboard science displays cover a very wide range of activities. These will include a SSB exhibit on plankton and the carbon cycle, led by Jonathan Sharples, also on-deck display of a Smart Buoy and other sampling gear. A much wider range of SSB exhibits was offered, but unfortunately there wasn’t space to include them.

3. Invitation to SSB Annual Science Meeting: Plymouth Marine Laboratory, 24-25 November 2015

All researchers who are directly involved in the SSB programme (either through research grant awards, research studentships, SSB cruise participation or SSB programme management) are invited to the 2015 ASM, to be held at PML, Plymouth on Tuesday 24 (from 09.30) and Wednesday 25 November (until ~16.00). The purpose of the meeting is to review progress made, particularly through the cruise programme. Whilst it is not expected that all data and samples will be analysed by then, this will be a key meeting in assessing initial results, strengthening links between WPs, and establishing whether or not SSB’s main components, and the programme as a whole, are ‘on track’ to meet overall objectives.

Online registration and further information for the ASM will be available in mid/late September via SSB pages on the NERC website, including a link to Plymouth hotels near PML.

Note that:

Most participants are expected to make their own accommodation arrangements (the exception is for WP leaders, Executive Board members and Advisory Panel members, for whom a group booking will be made)
For those involved in the programme (as defined above), reasonable costs for travel and accommodation will be met, expecting that 2 nights’ accommodation, and possibly three, will be required.
The agenda for the meeting will primarily be developed by the WP leaders and myself, identifying the main topics to be presented for discussion.
There will be the opportunity for WP-specific meetings to be held on Monday 23 November, also Thursday 26 November and Friday 27 November; to be arranged by WP leaders. Any extra costs for such meetings will need to be met from existing budgets.

4. Shelf sea science session at Ocean Sciences meeting; New Orleans, 21-26 February 2016

Abstracts are invited for session #9277 (EC017) “Physical and biogeochemical processes and the support of shelf sea primary productivity and carbon cycling” at the 2016 Ocean Sciences meeting, jointly organised by AGU, ASLO and TOS, and to be held in New Orleans.

The session will be co-chaired by Jonathan Sharples, Richard Sanders and Katja Fennel (Dalhousie), and the deadline for abstracts is 23 September.

Main conference page: http://osm.agu.org/2016/
Session information, https://agu.confex.com/agu/os16/preliminaryview.cgi/Session9277

Unfortunately it is not currently anticipated that there will be any additional SSB support for participation in this meeting, other than via existing awards.

Dr Phil Williamson

SSB Project Manager

Reflections

2015-09-07T11:40:00.000+01:00

By Sebastian Sims

Cruise DY034 has now come to an end, and with it the end of most Shelf Seas Biogeochemistry Programme field work.

From my perspective, this cruise has been a resounding success. Not only have I learnt a lot of scientific procedures and successfully sampled from CTDs, but also the other scientists have given me a good understanding of their work. I thoroughly enjoyed occasionally helping out with coring and trawling, as I found it fascinating to see the benthic fauna up close. I also enjoyed analysing some of the seafloor photos taken by Autosub. I was interested by the principles behind getting profiles of oxygen and iron concentrations in sediments, nutrient analysis, learning about multibeam and sidescan sonar mapping, as well as the role of gliders and benthic landers in collecting observations independently from the ship.

Outside of the science, this cruise has been a great experience in itself. The stunning sunrises and sunsets, meteor shower and seeing dolphins for the first time kept me going through the tougher days. I have also met a load of great people, who have all made me feel very welcome, and it would be a pleasure to work alongside any of them in the future.

I would like to thank all of the scientists, technicians and crew who made all of this possible. I know more than ever about what it means to be a marine scientist. For all those who have not been on a research cruise before, I would recommend it with the upmost enthusiasm.

I am shortly going to return to my studies, and I await my next cruise opportunity with great anticipation.

Heading back to Southampton

2015-09-01T17:30:00.000+01:00

We've now finished our SSB sampling and we are headed towards Southampton. Many of us are now transitioning from taking and processing samples and preparing equipment for use, to writing up reports and packing for mobilisation back to our respective home labs.

Sea Creatures: Sabellidae

Our thoughts often mix between reflecting on the expedition to getting back to our lives ashore. It's nonetheless a critical time as we want to ensure that all the work we've done has been well documented and that samples and data are archived properly so they can be of best use for years to come.

Below are some additional images of the sea creatures we found in the Celtic Sea during our sampling.

Sea Creatures: Octopod

Sea Creatures: Polychaete Sea Mouse

Working on the night shift

2015-08-30T10:00:00.000+01:00

By Rachel Hale

The scientists on RRS Discovery work all hours. The ship is expensive to run and the Shelf Seas Biogeochemistry (SSB) Project has a lot of different tasks to achieve and it would not be possible to do this without working 24 hours a day.

What this means is that a small fraction of the scientists and crew on board need to adjust to working during the night. The shift that I have been allocated runs from 6 pm to 6 am. Getting into the swing of it is hard as your body clock adjusts but this is the third cruise in this project where I have been asked to work the night shift so I am getting used to it. There are a few downsides: we miss all lunches and most breakfasts (although food is left out for us), we don’t see that much sunlight, and everyone’s day finishes as ours begins but there are lots of positives.

1.- Sunset

Sunsets at sea are spectacular things. The air is clear, the sky turns multi-coloured and the light reflects off the clouds.

A spectacular sunset.

2.- The big fauna comes out at night

A lot of the larger creatures like the cover of darkness. So far on this cruise we’ve seen two different types of shark, a sunfish, dolphins, a whale, garfish and many jellyfish. A lot of the fauna get attracted to the lights on the boat that shine on the water while we are working. This means that as they approach the boat they are easy to spot. We regularly watch dolphins play around our sediment corer as it hits the water.

3.- The lab is quieter

The controlled temperature laboratory we use on board is possibly the busiest part of the ship. It is a small lab in the middle of the ship where we keep the sediment we collect that is kept at the same temperature as the bottom of the sea. There are ten people working in there and bench and floor space is very limited. All the space that will be used is planned out months in advance but when lots of people are working in there it can become very cramped. During the night shift the majority of those who use the lab are asleep so we get the chance to work knowing we won’t be in anyone’s way.

4.- Getting involved with everyone’s work

Because there are so few people working at night we all help to collect each other’s samples. Over the three cruises I have had the chance to trawl for epibenthic megafauna (looking for large rarer invertebrates that live on the sediment surface), use a sediment profile imager (SPI) to make cross section images of the sediment water interface and helped deploy a large in situ flume (a device that sits on the seabed and creates a current that runs in a circle to look at how the mud and sand behave under different conditions).

SPI camera,

5.- Snacktime

The kitchen does not run 24 hours, so when we work nights there is no lunch put on. We eat dinner for breakfast and breakfast for dinner. You can get lunch put aside but sometimes it’s more fun to create snacks from the leftovers of dinner, toast and buffet bar. Salad mountains, rum and raisin ice-cream granola, peanut butter, jam, banana and nutella sandwiches, potato salad baps, and anything you fancy.

6.- Sunrise

The sunrises are as spectacular as the sunsets, with the added knowledge that the nights work is almost over and it’s nearly time for bed as everyone else gets up.

Worm holes and snail trails

2015-08-28T17:44:00.000+01:00

By Christina Wood

My job on the RRS Discovery is to characterise the activity of the species that live in the sediment.

I look at a process called bioturbation, which is when species living in the sediment create burrows or move sediment particles up or down. These activities stimulate microbial growth and encourage the cycling and release of nutrients and are important mediators of shelf sea processes.

To measure bioturbation we use coloured particle tracers we call luminophores, which are placed on top of sediment cores we collect in a 2 – 3 mm thick layer. These are bright coloured particles that can be easily seen when they are mixed into the underlying sediment.

There are many small worms, shrimp and snails living in the sediment that are constantly moving, grazing, hunting, burrowing, and bioirrigating (moving water to keep burrows and the sediment oxygenated). They can create vast networks of burrows such as those created by Nephrops norvegicus, the Norwegian lobster. They can create mounds and pits on the sediment surface like the Angular crab, Goneplax.

An Angular crab, which can create deep pits and large mounds around a burrow network.

We photograph the sediment under ultra-violet light, making the luminophore particles fluoresce so they can be easily identified compared to the surrounding sediment by an automatic computer program and the number of luminophore pixels per sediment depth calculated.

An example image of luminophore movement taken under ultra-violet light. It is easy to see where the luminophores have been moved by species activity. These trails have probably been created by small worms creating burrows which the luminophores have fallen down. This is an easy and effective way to measure species activity in the sediment in the shelf seas and we can relate this activity to nutrient fluxes measured over time.

Recovering the Smart Buoy’ systems

2015-08-25T17:00:00.000+01:00

We recently recovered two ‘Smart Buoy’ systems operated by Cefas. Several such observing systems have been deployed at various stations around the Celtic Sea since March of 2014. These systems allow us to understand variation in the ocean in a way that is similar to weather monitoring. The sensors can record a variety of variable crossing physics to biogeochemical themes. These systems allow us to see how weather and climate affect surface ocean conditions and the growth of marine algae via primary production. It can measure changes in salinity, primary production nutrients, chlorophyll fluorescence, dissolved oxygen, and suspended particles. There is also a string of temperature sensors down to 60 m depth.

Recovering a 'Smart Buoy' system

We used the ship’s sensor and sampling systems to calibrate the buoy sensors, both when deployed and recovered to check that everything is working as expected and calibrate any sensor drift. Together with the sediment samples being take in the area, these long-term observatory observations allow us to better understand the variation in way that can be achieved when ships are not present. This helps bridge understanding between site visits over the change of seasons.

Collecting images from the seafloor.

2015-08-22T07:47:00.000+01:00

By Henry Ruhl

We have completed sediment core sampling at our four main study sites. This is a key achievement for the trip. We are now sampling one other site that allows us to cross-reference our findings with those of other studies and a long-term study station with the nickname Candyfloss. This site is closer to the continental shelf edge and open ocean than we have been for most of the trip. Marine life spotting has been good and we even laid eyes on the RRS James Cook about ten miles from us. The James Cook is researching life in the canyons that extend just beyond the shelf edge. We will soon return northward to for the more AUV deployments, the fourth deployment of the NOC lander, as well as a few other remaining tasks.

We are using the Autsub3 autonomous underwater vehicle (AUV) during our cruise to collect photographic images of the seafloor, as well as sonar-based images of the shape and texture of the seafloor. We have been running the AUV in a ‘mowing the lawn’ pattern of parallel lines that are about ~5km long. After checking our seafloor shape and texture mapping for any obstacles, we ‘fly’ the AUV as close as 2.5 meters from the seafloor to collect colour photographs in the moderately cloudy waters of the Celtic Sea.

The images will be geo-referenced, which effectively turns the photo into a map like you see in Google Earth. As you can see below, that 2.5 m height above the seafloor still gives us images that are very useful for determining the identity size, and location of all the observed images. This can provide a landscape scale view of the seafloor and its inhabitants, which we can then use to improve estimates of ecological and biogeochemical patterns and processes.

The seafloor and its inhabitants

AUV photographs are particularly useful in estimating the distribution of biomass of larger animals that are not sampled well by trawls or sediment cores. Observed animals include crabs, shrimps, and anemones as well as fish. The images above and below come from a Celtic Sea site where the seafloor is dominated by sandy mud.

The seafloor and its inhabitants

Mini-Flume Experiments

2015-08-20T10:07:00.000+01:00

Sarah Reynolds. Senior Research Associate and Lesley Chapman-Greig, MRes student, are Marine Biogeochemists with the University of Portsmouth, and their research is looking at how the processes in marine sediments can contribute to the carbon and nitrogen cycles in shelf seas.

For one of their experiments, sediment from the seabed is collected from a NIOZ core and brought up to deck, where it is stored in a mini-flume alongside water collected from the just above the bottom of the seabed by the CTD. The mini-flume simulates resuspension events on the seabed. The sediment lies at the bottom of the mini-flume, with the water from the CTD above, which is stirred by paddles of the flume to simulate the action of currents on the bottom of the seabed, which can disturb the seabed sediments causing them to be mixed (the scientific term is re-suspended) into the overlying water column. During resuspension events nutrients and carbon stored in the sediments can be released into the water column.

Mini Flume

Over the course of the experiment (~3 hours), samples of water are collected from the mini-flume at certain time points and collected for inorganic nutrients, dissolved organic carbon, particulate organic carbon and suspended particulate matter. These measurements can then be used to determine the concentration of nutrients and carbon that are released into the overlying water column. As the mini-flume experiment progresses the paddles of the flume are moved faster and faster until complete bed failure occurs.

The increases in speed of the water moving above the sediment in the mini-flume, make it possible to measure how different current speeds close to the surface of the seabed may change the concentration of carbon and nutrients that are released from the sediments.

Sediment is collected for mini-flume experiments at three cohesive sediment sites, with each site having a different type of sediment, ranging from very muddy sediment with fine particles sizes to muddy sand and sandy mud. Depending on the type of sediment, the concentration of carbon and nutrients and the energy required to lift the sediment off the seabed varies, so by conducting this experiment with a variety of sediment types it is possible to discover how the concentration of carbon and nutrients mixed into the water column by seabed currents varies between different sediment types.

This cruise is final cruise in a yearlong project, where the same data have been collected at different stages of the seasonal cycle of the Celtic Sea. The data collected by this experiment can be used alongside other measurements, collected from the different sites at different times of the year, to get a good picture of how the suspension of sediments affects the carbon and nutrient cycles in the Celtic Sea, with the hope that these can be extrapolated to the Western European continental shelf.

36 years of working on Discovery

2015-08-18T08:00:00.000+01:00

By Peter Statham
Ocean and Earth Science, University of Southampton

When I first set foot on the old Royal Research Ship Discovery in 1979 in Cape Town I had little idea that in 2015 I would be on the Discovery once again but now on the most recent version of the vessel to carry this famous name.

I am interested in the chemistry of the ocean and how chemical processes affect the biology and other parts of the marine system. This aspect of oceanography is important in terms of understanding how the sea works and can be impacted by climate change.

On this trip we are studying where the essential nutrient iron comes from on the shelf and how it may move away into the open ocean. In some areas the element is at such low concentrations that it limits plant growth and thus impacts ecosystems, so it is important to know where it comes from, and one potentially important source are the edges of shelf seas.

Launching a glider from Discovery. Gliders move up and down through the water by altering their density and “glide” on their wings from one location to another in the upper ocean, whilst collecting data that is sent by satellite to shore when it is at the surface. This new model has a small propeller to help it occasionally overcome strong currents.

Whilst frequently demanding with long working hours I always enjoy the times at sea with the wide range of people on board, the constant challenges to be dealt with and the buzz when a long planned experiment finally works out. Whilst new techniques such as satellites and gliders are developing rapidly, ships are still essential tools in the study of the oceans. Discovery is a world-class research platform for UK marine science that will support our new generation of oceanographers into the future.

The animals on the seafloor of the Celtic Sea

2015-08-17T09:30:00.000+01:00

Yesterday we recovered some nice trawls from the sandy site. We also managed to get some images of the animals that live on the seafloor of the Celtic Sea, which is about eighty miles north by northwest of Land's End.

Octopod

Octopod_suckers

Ophiuroid_brittle star

Paguroidea_Hermit crab

Asteroid

Echinoid_ Sea Urchin

We've now finished most of the sediment sampling work at both our muddy and sandy sites. Tomorrow will likely be a busy day as we expect to pick up some lander, buoy and mooring equipment.