Maybe now this is my favourite country in the world!

2024 had barely begun when, on 9 January, the BBC announced that 2023 was officially the warmest year on record. A new daily global temperature record had been set on more than 200 days last year, according to analysis by the BBC of data gathered by the Copernicus Climate Change Service.

For Dr Fernando Rafael De Grande, like many other environmental scientists, this confirmation came as no surprise. Fernando has been studying the impact of warming temperature on Brazil’s delicate mangrove coastline for some time, but he spent 2023 working in Edinburgh with scientists from the Centre for Conservation and Restoration Science (CCRS) at Edinburgh Napier University.

‘The Centre is led by Professor Karen Diele at Edinburgh Napier, who also works and publishes on Brazil’s mangrove environment, so I have been familiar with her work for some time,’ explains Fernando, who studied his initial degree at São Paulo State University and is now a post-doc Research Fellow at the  Institute of Marine Science, Federal University of São Paulo (IMar/UNIFESP), Santos, Universidade Federal de São Paulo.

‘I was keen to expand my research, to take a more global approach – and wanted to improve my English – so I applied to the Brazilian government to sponsor an opportunity to work with Professor Diele here in Scotland.’ Edinburgh Napier’s international reputation for mangrove research was essential to satisfy the funding conditions set by the Brazilian government, which agreed to sponsor his fellowship.

For the past year, Fernando’s research at Napier has focussed on producing a meta-analysis and systematic literature review, to assess where and how much warmer temperatures will likely impact mangrove fauna production around the globe.

‘It is difficult to test the impact of temperature increase in the field’, he explains, ‘so I have collated published results from lab experiments from around the world, including many different species, and have found that, yes, increasing temperatures due to climate change can negatively affect mangrove fauna, which in turn could impact the mangrove forests themselves, given the animals’ important ecological roles. Many animal species included in our study grow and reproduce less under increased temperatures. This impact is expected to become particularly acute in the Indo-Pacific and western Pacific. I am now looking forward to soon submit the results of our work to a scientific journal for publication, together with Karen and my Brazilian supervisors.

Reflecting on his 12 months in Edinburgh, just before his return to Brazil on 13 January, Fernando said: ‘Karen’s team in the Centre have an international reputation for their work, and she has published globally significant research in many papers, so I have benefited directly from that [expertise]. Napier also has a good research infrastructure, nice labs and equipment for marine research, and I have been equally impressed by the other science labs at the university.

‘CCRS works as an interdisciplinary group, and that has been a totally new and very good experience for me. I have learned how to work in this type of research environment, with colleagues from diverse disciplines, doing and publishing valuable research together. Other Marine Biology students off Karen work in Scotland, and I have been able to interact with them and discuss our areas of individual research, and that too has been very interesting and productive.

‘My time here has also much improved my English, as I’d hoped. As an academic, I can read and write in English, but living here has greatly helped my conversational English.

‘For people from the tropics, like me, Scotland is very different and has a very beautiful landscape. I have loved Scotland, and the people in Edinburgh have been very friendly. It’s a beautiful city with wonderful architecture and the culture here is amazing. There are good free museums, and of course the castle at the centre of the city! It is very different from San Paulo.

‘I’ve also travelled around Scotland during my time here, to Fort William, Glasgow, Inverness, and St Andrews. Maybe now this is my favourite country in the world!

Although now returning to continue his postdoctoral research Fellowship in São Paulo, Fernando will continue to collaborate with CCRS into the future. He has already been invited to work on and co-author two papers with Karen and colleagues from the Centre and says ‘We already started to plan some exciting new joint research work here in Brazil also, and field work for this will already kick off in a few weeks.’

‘I am optimistic that I can apply our research when I return to Brazil, to improve mangrove management and conservation in this region of the world. Our research is relevant not only for Brazil, but also for other countries with mangrove environments.’

Funding was provided by a FAPESP research grant No. 2022/12556-2.

Marine coastal organisms benefit from oxygen fluctuations

Fluctuations of oxygen levels in marine coastal ecosystems are important to determine the response to climate change  of marine fauna.

That is the finding of a paper published in June for The Royal Society, based on research involving Professor Karen Diele and Dr Marco Fusi, a postdoctoral fellow in the School of Applied Sciences at Edinburgh Napier University. Both have been working with Dr Jenny Booth , who is the paper’s lead author, and Professor Christopher McQuaid of Rhodes University, South Africa. The experiments that led to the findings have been conducted in the aquarium facilities of the St Abbs Marine Station, on the south East coast of Scotland, in collaboration with Marine Station researcher  Erica Chapman.

Coastal animals exist in habitats that are characterized by daily and seasonally fluctuation of environmental parameter:: for example, oxygen cycles vary between day and night and summer or winter.

Marine species evolve in this fluctuating environments and they have developed strategies to exploit cycling environmental change.

The team’s research – entitled Diel oxygen fluctuation drives the thermal response and metabolic performance of coastal marine ectotherms published in the Proceedings of the Royal Society B,  shows that both velvet crabs and blue mussels normally exploit fluctuating daily oxygen supersaturation to cope with nightly oxygen undersaturation and overall to improve their thermal resistance.

The experiments that led to the findings have been conducted in the aquarium facilities of the St Abbs Marine Station (c) Jenny Booth

But as the environment alters at an increasingly fast pace, due to anthropogenic activity, the impact on natural feedback mechanisms is affecting the ability of these species to adapt to future thermal stress. The adverse impact is likely to be true for most coastal ectotherms, or animals that depend on external sources of body heat, as they rely on the same feedback mechanisms.

“The increasing metabolic demand of animals under warming are sustained by producing periodic oxygen supersaturation through coastal primary producers,” explains Marco Fusi. These are plants, algae and some bacteria that can photosynthesize.

“We demonstrate that the provision and resultant variability of oxygen by primary production are important drivers of the thermal responses of coastal animals, and the intensified response we see is foreseen to become increasingly important under future climate change,” adds Karen Diele.

This thermal response of both plants and animals results from the complex interaction of several factors, beyond temperature alone. “While primary producers will have their own specific responses to ocean warming and acidification, it is likely that coastal habitats such as seagrasses, kelp forests, mangroves and coral reefs will be important as refugia, where oxygen variation can drive the metabolic performance of animals in a changing world,” adds Marco.

“As primary producers, they are likely to have an increasingly important effect under climate warming; both on permanent residents and transient animals that use these habitats as nursery sites.

The disappearance of diverse communities of macroalgae in coastal waters is therefore a threat to biodiversity, not only through habitat loss, but also through reduced oxygen variability and the effects of this on animal thermal responses.”

The full paper can be read here