Abbie Chapman: My Research

Hello Ocean Explorers!

I’m Abbie and I’m very excited to be one of your facilitators for the ‘Exploring our Oceans’ MOOC.  I’m just about to start the second year of my PhD at the National Oceanography Centre, where I will be focusing on seafloor hot springs (or hydrothermal vents) around the globe and the variety of life that depends on them.

In this blog post, I’d like to introduce you to the research I’m doing for my PhD and why it is particularly relevant today.  I’ll add a section at the end about my background, for those of you that might be interested in how I came to study these exciting ecosystems.

What are hydrothermal vents?

Hydrothermal vents are hot springs found on the seafloor that tend to be found in tectonically active areas, where the Earth’s tectonic plates move apart or come together (at spreading centres and subduction zones).  If you look at the diagram below, you can see that hydrothermal venting occurs when cold seawater seeps down into the Earth’s crust.  Here, it is heated by magma and mixes with the wealth of chemicals present in these newly-forming rocks.  This means that, when the water returns to the seafloor, it has been chemically altered and is incredibly hot.  This fluid is called hydrothermal fluid.  Hydrothermal fluid varies in temperature and mineral content, which also affects how it appears when you see it.  If it is lower in temperature (but still very hot!) and emerging from cracks in the rocks, it is called ‘diffuse venting’.  If the temperature is higher and there are high levels of light-coloured minerals, ‘white smokers’ are formed.  Lastly, if the temperature is higher still and darker-coloured minerals are being ejected, ‘black smokers’ can be seen.  The ‘chimneys’ often associated with hydrothermal vents are formed as the minerals precipitate out of the fluid (upon contact with cold seawater) and accumulate on the seabed, building up into chimneys.

 

How do animals survive at vents?

The discovery of life at hydrothermal vents changed our view of life on Earth.  Before the discovery of the life at vents, we thought that life depended on sunlight (to generate energy by photosynthesis) to survive.  The animals found at the first-discovered hydrothermal vent (on the East Pacific Rise) proved otherwise.  Instead, these animals have a symbiotic relationship with bacteria.  These bacteria create energy via chemical reactions with sulfur and sulfides.  This chemically-sourced energy is why the animals dependent on these bacteria are called ‘chemosynthetic’ (or, relying on chemosynthesis).

 

Why do I study the biodiversity of hydrothermal vents?

Hydrothermal vents have been explored for around forty years (which is actually quite a short length of time, when you think about how long we’ve been studying terrestrial environments for).  During this time, researchers have documented the discovery of uniquely adapted animals – creatures that are able to thrive in toxic environments without light, at the bottom of seas around the globe. In addition, researchers have mapped the distributions of vent animals across space and through time, to try to identify biologically-defined zones (similar to the savannah, rainforest and tundra separations we make on land) and to investigate what influences the vent communities around the world and what makes them so variable (e.g. large numbers of worms are seen at North-East Pacific vents, whereas crabs and limpets dominate Antarctic vent environments).

The biodiversity of hydrothermal vents has been studied by other researchers.  They have documented how many species have been found at each vent site and have run statistical analyses to compare communities.  So far, it has been found that vent systems have low numbers of species (or low species richness), but high numbers of animals (high biomass).  However, there have not yet been statistically powerful tests to compare the diversity of vent communities around the globe.  It is difficult to make statistically strong comparisons between vents as sampling methods differ between cruises and some vents have been studied more often than others.  For my PhD, I will be using new statistical techniques (and ‘R’ programming software) to study the biodiversity of hydrothermal vents from a new perspective, to try to determine where the diversity ‘hotspots’ are around the globe.

Why now?

My area of research is likely to pop up more and more frequently in the news in the coming years, as vents are geologically interesting systems.  They host a wealth of metals and minerals that are used in everyday technology like smartphones and laptops. If companies are looking to mine these deep-sea environments, we need to understand what this will mean for the animals that live in them, to plan the best way to protect them.

Deep-sea mining is a destructive process that will likely reduce biomass and may cause species loss. As vents are low in species richness to start with, we do not yet know what impact the loss of even one species would have on a vent ecosystem.  However, we have the unique opportunity to quantify vent biodiversity patterns and drivers, to identify the best means of management, before policies and guidelines are finalised for industry.  This is an unusual and exciting opportunity to have, when you consider that most protected areas on land were designed after some human impacts had already taken place.

 

How did I come to study hydrothermal vents at the University of Southampton?

Firstly, I did not take science A levels.  I studied Chemistry and Mathematics to AS level, but took Geography, French, and English Literature to A level.  As a result, I could not study Oceanography for my undergraduate degree at Southampton (without a foundation year).

I studied Physical Geography at the University of Southampton and managed to take some modules at the National Oceanography Centre (NOC) in Physical Oceanography (using a lot of maths to look at temperature, salinity, and the transport of heat around the world), enabling me to change my overall degree to Geography with Physical Oceanography. It was only when I took on a Masters degree at the NOC that I was able to choose biology and ecology modules and I loved them!  I was exposed to deep-sea ecology for the first time and was privileged to be taught by Professor Paul Tyler, who was awarded an MBE for his contributions to deep-sea biology!  I was also fortunate enough to experience fieldwork in the Solent with a micro Remotely Operated Vehicle (ROV) on a course with Dr Jon Copley and I knew that I couldn’t stop learning about this ‘new underwater world’.  I completed a research project with Jon as part of my Masters course, analysing videos and imagery recorded using an ROV at an Antarctic vent.  Again, I knew that I couldn’t stop my studies there!

After my Masters, I found Oil Spill Response Limited and was fortunate enough to work with an amazing team of people in both Business Development and Consultancy trainee roles.  I underwent response training and learnt how to model oil spills!  However, when I saw PhD opportunities that would enable me to study deep-sea environments in more detail, I had to apply.  Now, I’m a (very lucky) student researching hydrothermal vents at the University of Southampton’s National Oceanography Centre, where I am fortunate enough to also participate in teaching and public engagement activities, just like this MOOC!

I think the moral of this story is that, if I had taken science A levels, I could have been studying vent ecosystems sooner (and perhaps more confidently).  However, the ‘long way round’ was still a possibility, so there is no need to give up on a career path because you fear you might not have the right background.

Back to the MOOC…

You’ll be learning about deep-sea mining and spectacular vent environments as part of this course and I’m looking forward to learning with you!  Keep an eye on the MOOC blog for more posts about my research and the research of other mentors on the MOOC too!