HAIKOU, April 25 (Xinhua) -- At midday, sunlight pierces the rippling surface of the South China Sea, scattering golden flecks across the one-meter-deep shallows. Lying prone on the seafloor just off Yongxing Island, Huo Da remains as still as a strand of seagrass.
Wearing a dive mask and snorkel, clad in a stinger suit, and holding a waterproof camera, he documents the hidden wonders of the ocean: a rare seagrass flower that blooms just once a year, an octopus that extended a curious arm to brush his hand, a green sea hare perfectly hidden among the blades of grass.
This 33-year-old, who grew up in a rural village in Baoding, an inland city in northern China, has now found a sense of belonging among the tropical seagrass beds of the south.
"Here on Yongxing Island, you don't have to dive deep or go far," he said. "If you look closely, life is right beneath your feet."
Each of Huo's dives lasts one to two hours. After surfacing, he returns to the Xisha Marine Environment National Observation and Research Station on the island.
As a researcher there, he spends most of his time collecting data on water quality and marine life, studying the patterns and changes in the surrounding waters, and compiling his findings into detailed reports.
Founded in 2009, the station is home to nine resident researchers who monitor and study oceanic environmental dynamics and reef island ecosystems, providing scientific support for the ecological conservation of the Xisha Islands.
ROAD THAT LED TO THE SEA
Born in 1992 in Baoding, Huo spent his childhood surrounded by fields rather than waves. Yet from an early age, he was drawn to the mystery of tropical oceans.
He studied aquaculture at a university in Wuhan, central China, and later moved south to Guangzhou for his graduate studies, where he began researching Holothuria leucospilota, the black sea cucumber.
It wasn't until a 2016 scientific expedition to the South China Sea that he saw one in the wild. "Seeing a sea cucumber in its natural habitat, not in a farm or a lab, was an entirely different experience."
Two years later, after earning his master's degree, he came to Yongxing Island and joined the Xisha station, becoming an observer and chronicler of this tropical marine world.
"The ecological environment in Xisha is excellent, with rich biodiversity. It's a paradise for marine scientists," he said.
As China's southernmost city, Sansha has made marine ecological conservation a top priority since its establishment in 2012.
The city has introduced regulations such as the marine environmental protection provisions and the sea turtle conservation regulations. It has encouraged fishers to shift to alternative livelihoods, carried out regular coral reef restoration and seagrass bed surveys, and established a sea turtle rescue and conservation center.
Huo uses his camera to capture life beneath the waves. He has photographed and filmed more than 400 species of marine creatures, including sea hares, stonefish, octopuses, floating anemones, hermit crabs, and sea turtles. Some species on his laptop still await classification.
"Every time I dive, I come across one or two species I've never seen before," he said.
"Marine creatures are truly fascinating. Octopuses are intelligent and curious. They swim toward me, reach out their tentacles, and gently touch my fingers. Their nervous systems are spread throughout their bodies, allowing them to change color constantly," Huo said.
Some fish are also capable of changing color. Once, he saw a gray conger eel. At first, it had dark spots on its body, but then it turned completely white and spread its wide, translucent dorsal fin. "I couldn't help but wonder, is this still a fish?"
Sea cucumbers are considered highly evolved creatures. Some species, when threatened, expel their internal organs as a defense mechanism, and later regenerate them. There are over 100 sea cucumber species in the South China Sea, he said.
"The more time you spend underwater, the more you begin to recognize them," Huo said. "Day versus night, young versus old, you start piecing together their life stories. And eventually, you feel a deep reverence for life."
Among all the aquatic creatures, Huo's favorite is the gently swaying seagrass beds. They play a vital ecological role -- purifying the water, capturing and storing carbon, stabilizing coastlines, and providing food and shelter for marine life.
Seagrass is highly sensitive to water quality, and around Yongxing Island, he has seen it grow more plentiful. "In places with poor water quality, seagrass dies off," he said.
A DIFFERENT WAY OF SEEING
The ocean covers more than 70 percent of the Earth's surface and serves as the cradle of life. China is one of the world's richest countries in marine biodiversity, with over 28,000 recorded marine species, accounting for about 11 percent of all documented marine life globally.
Over the past decade, China has made significant progress in marine ecological conservation, pollution control, and biodiversity protection. A national action plan released last year set a clear goal: by 2030, the area under China's marine ecological protection red line will reach no less than 150,000 square kilometers.
Still, Huo believes humanity knows far less about the ocean than it does about the moon.
Part of the reason, he said, is perspective. "We often view the sea through a land-based, human-centered lens. We call marine animals sea cucumbers, sea hares, sea horses, but you never hear of anything on land called a 'land something.'"
"Some people still see all marine life as seafood," Huo said. "No matter how magical or beautiful the creatures I share online are, someone always asks, 'Can you eat this?'"
To Huo, true conservation begins with understanding.
"If you know nothing about the ocean, and someone suddenly tells you to protect it, it's like being asked to protect aliens," he said. "People need to first understand their environment; only then will they begin to care about it."
To help bridge that gap, Huo started sharing his underwater photography and marine knowledge on social media. His posts have drawn unexpected attention: a documentary filmmaker reached out, hoping to visit the island for filming. One viewer, inspired by Huo's footage of seagrass beds, learned about the ecosystem for the first time and even decided to join seagrass conservation efforts.
Huo is now co-authoring a book on South China Sea marine life with a friend.
On the Chinese short-video platform Douyin, his profile tagline reads: "Life is water." He once read a fable where a young fish asks its mother, "What is water?" The mother replies, "Water is like the air we breathe. It's so natural we don't even notice it."
His WeChat nickname, Merapi, comes from Mount Merapi, a volcano on Indonesia's Java Island that he summited in 2016.
"Life is like water, which is colorless and tasteless. Everything we go through is life itself. It can be deeply felt, and it can be given meaning," Huo said. "Even if life feels as plain as water, we should always keep a fire burning in our hearts."
(Reporting by Han Song, Cheng Lu, Zhong Qun, Chen Ziwei and Xia Tian)■