<h5>The sea of Sanmen Island, overlooked from above, is crystal clear from the shore. </h5>
At 8:30 a.m. on July 27, on the edge of Sanmen Island, about 8 kilometers away from Shenzhen's Dongchong Beach, three speedboats broke anchor and stopped, and 10 frogmen wearing diving equipment jumped into the water in pairs.
On the seabed 3 meters below sea level, colorful corals sway in the sea, like an underwater garden. The fish, shrimp and crabs hid one after another, and after a while, they came out again and swam with these frogmen.
These frogmen are coral reef census volunteers. Since 2007, Guangdong has carried out 12 consecutive years of coral reef census public welfare activities, attracting more than 1,000 diving volunteers. They hope that the data from the census will provide a reference for government decision-making and scientific research, and arouse public awareness of the protection of coral reefs.
<h5>Coast corals</h5>
<h5>Huo's shrimp</h5>
<h5>Avin Silk Shell (Baby Snail).</h5>
The coral ecology of Sanmen Island is good, but it is still not excellent
At 8:00 a.m. on July 27, next to the diving shop next to Dongchong Beach in Shenzhen.
"Everyone take the sample, put on the wetsuit here first, and the sample line is laid out on the back of the oxygen cylinder to go into the water." Zhang Yuxiang, a visiting professor at Guangdong Ocean University, told the others.
At 8:30, from above, the turquoise waters are crystal clear.
"The seabed can be seen on board, the water is very clear, and it is very rare in this typhoon season." Zhang Yuxiang said while wearing an oxygen bottle. "Captain Sun Yu and I will go down first to lay out the sample line, and then we will carry out a census along the sample line." When he finished, he rolled over from the rim of the boat and went into the water.
The sea temperature is about 29 degrees, and the underwater visibility is greater than 8 meters. After Zhang Yuxiang and Sun Yuchao arranged the sample line, they pounced twice, and the fish investigation team went into the water.
The Twin Sawfish Whirlwinde spun around in the coral, the Indian paramycot remained motionless on the sand, and the lead-dot polygesteria foolishly wandered around the volunteers.
The invertebrate survey team was then launched, followed by the coral reef matrix survey team, and a bay splash was stirred up at sea level. Each team is equipped with an underwater camera and record board, and the divers swim along the census line, measuring and recording the size of corals, observing the density of marine life such as fish and invertebrates, and investigating the pollution of landfill on the seabed.
<h5>Double sawfish</h5>
<h5>Pacifier Aoi</h5>
<h5>Lead-spotted multi-era pufferfish</h5>
A speedboat is about to sail into the reef census waters.
"Hey, hey, hey!" The captain shouted loudly and made the gesture of someone underwater. The speedboat stopped at the sound of shouting. In order to prevent the relevant boats from entering the census range of the diving team and ensure the safety of the underwater census workers, a red float is set up at sea level, and the captain will always pay attention to the boats in the surrounding waters.
"From the overall point of view of today's census, the living condition of coral reefs is very good, which is a very good thing." Zhang Yuchun said.
"Our census site, Sanmen Island, is one of the best corals growing at many nearby census sites, but objectively speaking, the coral conditions here are not excellent." As a result, the current situation of coral reefs is not so optimistic. Zhu Ruibao, captain of the diving team at Tsinghua University, said.
<h5>Spiny corals</h5>
<h5>End whip jellyfish</h5>
<h5>Doreen giant finger anemone</h5>
Accumulate first-hand data for decision-making and scientific research
Colorful coral reefs are the "metropolis" of tropical marine life, and the calcium bones secreted by different forms of reef-building corals create multi-layered spaces that provide a place for various creatures to inhabit, attach or shelter.
Liao Baolin, head of the Guangdong Coral Reef Census Project, said that due to various factors such as climate warming, frequent human activities, and seawater pollution, the coral coverage rate in the South China Sea has been greatly reduced in the past two decades. "About 1/10 of the world's corals have been destroyed, and 1/3 are expected to disappear in the near future."
The coral reef census can accumulate the latest ecological data, and the volunteers hope that these data can be used as a reference for government decision-making and scientific research, while arousing public participation in coral reef conservation and reducing the damage to coral reefs.
Sun Yuchao is a die-hard fan of coral reef census, and since 2015, he has flown from Beijing every year to participate in coral reef census activities. "I've been participating in the coral census for five years. In the past five years, I have found that topics such as coral census and marine environmental protection, whether it is the attention of social organizations or individuals, have been greatly improved. Now many diving shops, diving enthusiast organizations, etc. are involved in coral census activities. ”
<h5>Cherry blossom cone anemone</h5>
<h5>sponge</h5>
<h5>Spiny soft corals</h5>
【Zhiduo D】
How do I become a Coral Census Volunteer?
Registration method: Pay attention to the "Zhi Coral" WeChat public account to register
Professional qualifications: Diving level must be at least AOW (ADVANCED OPEN WATER DIVER, open water advanced diver, AOW water depth limit is 30 meters, and can do night diving) or above, to have more than 30 bottles of diving experience.
Equipment: Coral reef census activities should carry more than ten kinds of census equipment such as handheld GPS locators, sample lines, underwater cameras, floats, ropes, record boards, pencils and so on.
Training and learning: Before participating in the coral reef census, systematic theoretical learning and skills training is required. For example, the scope of the coral census activity, the census items, the tools and usage needed, the need for measurement, the types and identification methods of organisms in the sea area, and the precautions on the seabed.
<h5>Coral reef census volunteers record coral growth data on the template and photograph the coral growth status. </h5>
Writing/Photography: Nandu reporter Chen Zhigang Zhang Jiapei intern Liu Jiajie
Some of the images were provided by the respondents