The Arctic Sub-Arctic Habitat Survey is an important part of China's 15th Arctic Ocean Scientific Examination, which is influenced by factors such as climate warming, and increasing numbers of warm-water species are expanding northward, affecting and changing the biological distribution pattern of the Arctic Ocean.

The reporter took the "Xuelong 2" polar scientific research icebreaker to interview in the Arctic Ocean and saw that the expedition team obtained rich samples of benthic organisms, showing the diverse world of underwater organisms. At the same time, some new surveys and findings are advancing research on the response of Arctic benthic ecosystems to rapid climate change.

The picture shows the expedition team members recovering bottom trawls and inspecting benthic animal samples. Photo by Xinhua News Agency reporter Liu Shiping

More than 5000 samples reveal Arctic benthic biodiversity

Benthic organisms living on the surface of the seabed or in sediment are important "rations" for fish, marine mammals and seabirds. At the same time, they swallow the organic matter settled from the upper seawater, and then "release" the nutrients back to the seawater, which is equivalent to "fertilizing" the sea and supporting the growth of primary producers such as phytoplankton.

"The expedition team successfully completed bottom trawling operations at 14 stations in the northern waters of the Chukchi Sea and obtained rich samples of benthos, providing valuable first-hand information for in-depth research on the diversity and community structure of the Arctic benthos." Liu Kun, captain of the ecological investigation team of the expedition team and associate researcher at the Third Institute of Oceanography of the Ministry of Natural Resources, said.

Picture of samples of parts of the Northern Ice Ocean subspecies that have been arranged and arranged.

After preliminary sorting, a total of more than 5000 samples of benthos were obtained from the bottom trawl, covering six categories: echinoderms, coelenterates, molluscs, arthropods, annelids and bryozoans, with high species diversity. Among them, the dominant species are mud starfish, North Pacific snow crabs, umbrella-shaped sea gills, parasitic sea anemones, and tubular polychaete.

"There are also representative creatures such as shark tail, long-tailed shrimp, double-eyed shrimp, shrimp, etc., which have accumulated valuable physical resources for polar ecological research," said Huang Yagan, a scientist and senior engineer at the Third Ocean Research Institute of the Ministry of Natural Resources.

Yuan Yashin believes that large Arctic subspecies grow slowly, have a long life span, and have a fixed habitat, so they can be used as ¡°indicators of climate change¡± and their population structure will clearly reflect environmental changes in a few years to decades, comparing the results with the samples and data from Arctic journeys, which will provide critical support to reveal how Arctic subspecies ecosystems respond to climate change.

The picture shows scientific expedition member Huang Yaqin and the samples of benthos in the Arctic Ocean he obtained. Photo by Xinhua Agency reporter Liu Shiping

Spatial gradients reveal benthic distribution patterns

"In the Arctic waters, scientists have recorded more than 4,000 species of giant and macrobenthic organisms, which are richness beyond many people's imagination. However, human understanding of benthic organisms in most of the Arctic Ocean is still limited." Liu Kun said.

In addition to trawl sampling, this expedition team deployed multiple sets of seabed biological imaging observation systems.

Image for Liu Qing (right) and other scientists and just returned to the ship's underwater biology imaging observation system.

Liu Qing said that by obtaining underground habitat localization imaging data, analyzing underground biodiversity and distribution patterns, and continuously tracking climate-driven species northern migration and settlement restructuring, he strives to answer "what changes are happening in the Arctic underground ecosystem" and "why these changes occur", so as to provide quantitative evidence and early warning for Arctic ecological conservation and fisheries management.

Unlike before, this survey was the first to deploy an underwater biography observation system based on the depth of the water on the land shelf - land slope - deep sea surface. The image data obtained showed that the structure of the communities showed significant differences with the depth of the water: the land shelf and land slope area are favored by mud stars, umbrellas, etc., and the deep sea basins appear giant marshmallows - the high density belt of transparent corga marshmallows.

Giant seafood captured by the underwater bio-imaging observation system ¨C Transparent Kolga Seafood (China¡¯s 15th Northern Ice Ocean Science Examination Team)

Time gradient to capture ¡°Ice Algae pulse¡±

"Different from previous years, which were mainly carried out in the platform area of Chukchi Sea, this benthic monitoring station is concentrated in the continental slope area and deep water area in the northwest of Chukchi Sea. It is located at the intersection of Atlantic sea water and Pacific sea water, with sufficient nutrient supply, higher benthic biodiversity and more complex community structure." Liu Kun said.

Image for scientists are recycling the bottom trawler. news agency reporter Liu Xiaoping

He tells about an unforgettable sampling experience, namely the landslide station drawing network operation at 75 degrees 18 north latitude.

"Once the net goes down, there are not only a considerable number of starfish, sea snake tails, snow crabs and tube-dwelling polychaetes in the net bag, but also a lot of intact sea lilies and sea gills are brought back from the net clothes and frames." Liu Kun said that the harvest was so abundant that the team members spent about 3 hours towing and processing samples at the bottom of the stern deck, and another 2 hours packing and taking photos of the samples indoors.

The team noted that in the continuous observations of the early-mid-end melting period, the ocean floor images showed a significant increase in near-bottom particles and splinters, and synchronized with the "sinking under the ice algae" of the surface water bodies.

¡°Unexpectedly, we have captured a large number of splinter, cluster-shaped algae clusters in an area of approximately 2,200 meters in the ocean through the ocean-bottom biomaterial observation system, which shows that the upper-southeast clustering in the Arctic oceans is equally likely to occur,¡± said Liu Qing, which provides a key clue for subsequent long-term continuous observations and cross-regional comparisons, and opens a new window for analyzing the upper-southeast clustering process.

Liu Qing said that this expedition stepped in the key window period of the initial melting of sea ice: ice algae and organic particles began to sink rapidly, the expedition team synchronized the bottom trawler and box sampling machine to obtain samples, coupled the "process" of sea ice melting with the bottom habitat "samples" time, thereby identifying "which bottom habitats are eating" and "how much", so as to effectively evaluate the changes in the bottom food network under the background of Arctic sea ice removal.

Speaking about how to better conduct Arctic subsidiary investigation and monitoring in the future, Liu Qing and Huang Jian suggested to strengthen international cooperation to establish efficient and standardized Arctic large subsidiary populations monitoring, while expanding the monitoring of micro and small subsidiary populations; better utilize advanced equipment such as manned dives, unmanned remote dives and submarine biomaterial observation systems to conduct visual surveys, and conduct comparative subsidiary studies between regions of the Northern Ice Ocean.

Scientists are recycling the bottom drawing net (July 23, 2025). news agency reporter Liu Xiaoping

Scientists in the processing of the sample of subspecies brought back by the bottom trawler (September 10, 2025).

Samples of subspecies of the Northern Ice Ocean (August 3, 2025), Xinhua news agency reporter Liu Xiaoping

Scientists are recycling the underwater bio-imaging observation system (August 14, 2025).

Scientists are recycling the underwater bio-imaging observation system (August 14, 2025).