Exploring the deep ocean
In January 2025, Hong Kong will host the 17th Deep Sea Biology Symposium, a major international event in the field of deep-sea biology that has never been held before in Asia. The man who will be organising this event is leading marine ecologist Professor Pei-Yuan Qian. He’s the David von Hansemann Professor of Science and Chair Professor in the Division of Life Science at the Hong Kong University of Science and Technology. Croucher News caught up with him recently to talk about his work.
First, we asked about the symposium, which will be partially funded by a grant from Croucher.
“This is the only international conference that really focuses on deep-sea biological science. “And, of course, to exchange views regarding the deep-sea environment, not just biology.” Most of the deep-sea research goes on in international waters, which makes collaboration between nations imperative.
“The deep sea is part of our common heritage and is subject to the UN Law of the Sea, specifically the Agreement on Marine Biodiversity of Areas Beyond National Jurisdiction, Qian told us. The deep ocean is also expensive to explore, making collaboration more important, especially between developed and less developed nations.
One of the topics that is likely to come up at the symposium is what Qian calls “the balance between deep-sea conservation and deep-sea mining.”
It’s a complicated topic. The target of the Kunming-Montreal Global Biodiversity Framework is to “conserve 30% of land, water, and seas.” But Qian explains that 95% of the ocean is unexplored. So, at this stage, “for most deep-sea seafloor habitats, we have no idea what kinds of marine biodiversity are there, what needs to be protected, why they need to be protected, or who will be responsible for protecting those habitats. We do not have solid scientific evidence to determine where industry can really carry out mining without harming the deep-sea environment or the biodiversity, or where it can’t.”
On the other hand, given the expense of this kind of exploration, many of the resources for it come from mining operations looking at the environmental impact of their work.
Qian also talked about the physical challenges of doing research in deep-sea biology. In a recent research mission to the Mariana Trench, “one probe exploded at a depth of about 9,000 metres,” he said. Several others were also lost.
Qian also had to carry out the dissection of samples of amphipods on a ship that was pitching and rolling in heavy seas. “That wasn't easy, you know, because your stomach is already upset, your head is a bit dizzy, and the lights of the microscope are very bright. And yet you have to focus.”
But despite these challenges, Qian was able to bring back 23 specimens of amphipod, a shrimp-like crustacean.
We asked if there were any surprise findings from this research. He gave us one example: “At almost 11,000 metres down, there's no light. You would think that this animal should not have a really functional eye, or the eye should be very small. But we found that their eyes are very big and very complicated. We don’t know why.”
A recent key finding of Qian’s lab was that the genome of sea creatures is expressed differently depending on whether you analyse in situ or on the ship miles above.
“We were doing work at the South China Sea, where the depth is not that great—1,300, 1,500 metres. We analysed the DNA/RNA in situ, on the sea floor, and then brought the sample to the surface and analysed it again,” he told us.
“When we compared the two sets of data, we found that the expression of the genes was totally different. Which means if you really want to study their gene expression, you have to do it in situ, at depth, rather than on the deck.”
Qian’s lab has a wide range of deep-sea samples from around the world and also uses cutting-edge equipment for genomic analysis: “We have a very good molecular platform, and we were the first lab to sequence deep-sea animal genomes.”
This technology and the excitement of the mysteries of the deep are attractive to young researchers. “People find it very exciting. So that's why I have never had a problem with recruiting new PhDs or post-docs.”
Qian actually started his career as an intertidal ecologist. “I was working on the larval recruitment of intertidal animals, subtidal animals to begin with.”
Then, back in 2004, he was approached by someone from the China Deep Sea Research Programme, who said they could fund him to work in deep-sea biology. After working for a time in that field, he was awarded research funding by the King Abdullah University of Science and Technology in Saudi Arabia to carry out research in the depths of the Red Sea; “that area had never been the subject of biological research. At that point, I completed my transition to being a hardcore molecular ecologist.”
International collaboration remains core to the work Qian is doing. Recently, he’s been busy working with a number of international research groups and organisations to set up a unique opportunity for 11 overseas scientists to join a Chinese research vessel to explore the Mariana Trench. “We leave Qingdao on 10 August, and then we'll come to Hong Kong on 23 September,” he told us. “All of the scientists are going to have a chance to dive down with the Jiaolong HOV (human-occupied vehicle) to deep-sea seamounts on the east side of the Mariana Trench. They're going to have their first chance of exploring the deep-sea environment with their own eyes.”