East China's coastal city Qingdao has gone all out to clean up invading algae to assure smooth going for the Olympic sailing event, achieving notable results, local officials said.
Since late June, more than 10,000 soldiers and civilians have gone to sea and worked along the coast each day to weed out the blooming algae, which has swelled to stretches of up to a few kilometers long, said Wang Shulian, deputy director of the Qingdao Oceanic and Fishery Department.
Qingdao, a scenic port about 550 km southeast of Beijing and known for Tsingtao beer, is a co-host city for the Games. Sailing events will be held here from Aug. 9-23.
Since late May, the coast has been coated with a vast algae bloom. A bright green covering of algae can be seen smothering beaches and extending out several hundred meters.
The algae, enteromorpha prolifera, was first detected on May 31off Dagong Island, well out to sea. The current and winds were moving the algae patches toward the coast.
As of June 29, the algae had affected 13,000 sq km, 400 of which were covered by the outbreak.
By July 2, about 180,000 tons of algae had been removed from the water and seashore. The algae covered only 48.8 sq km of water.
"We have stressed to all those devoted to this campaign that priority should be given to the Olympic venue and we expect to eliminate all these algae before July 15," said Yuan Zhiping, assistant to the chairman of the Qingdao Olympic Sailing Committee.
UNSIGHTLY BUT NOT HARMFUL
The algae is not harmful by itself. It absorbs carbon dioxide and actually cleans the water.
"The algae is of various types. It will bloom if the temperature and salinity are right," said Wang.
To quickly eliminate the algae, which could interfere with the Olympic sailing event, the Shandong Provincial Science and Technology Department earmarked 2 million yuan (291,622 U.S. dollars) to track its source and motion within 15 to 20 days.
The State Oceanic Administration (SOA) monitored the course of the algae into the Olympic venue with tracking bottles. Experts dropped 80 bottles in the water around the venue after the bloom was spotted.
They concluded that some of the algae was from the waters of Rizhao and Jiaonan, the central region of the Yellow Sea, to the south of Qingdao.
The SOA's North China Sea branch, in charge of water quality monitoring for the sailing venue, last Wednesday released results from 22 water quality monitoring stations. They showed the nutrient content in the water had continued to fall and the water quality was fit for sailing competitions.
AFFECTING LIVES, BUSINESSES
Although the exotic algae flowing from the central region of the Yellow Sea would not influence the water quality off the Qingdao coast, the algae invasion affected training by sailing teams preparing for the Olympics. So far, athletes from more than 30 countries and regions have come to Qingdao to train for the Games.
As of June 28, more than 32 percent, or 15.86 sq km of the guarded sea area for the Olympic sailing competition, was covered by algae.
The algae has also deterred local residents and tourists from enjoying the seashore. The city opened only the first bathing beach on July 1, the usual annual beach opening day.
All other bathing beaches along the vast seashore were kept closed, as floating algae prevented staff from installing shark defense nets.
"We have not enjoyed ourselves fully," sighed Xuan Yurong, a young mother from central China's Zhengzhou City, who was with her5-year-old daughter. "We traveled hundreds of kilometers simply to enjoy the sea."
Mother and daughter picked bits of algae from their skin after taking a dip in the cool sea at the beach.
The severe algae outbreak has also dampened local coastal businesses. On July 2, Zhang Laoban, who runs a fleet of 10 motorboats, sat gloomily at the city's third bathing beach. It was his third day without work.
"I have lost all my customers because of the algae," he said, shaking his head. Even cutting his fees by half wasn't enough.
Two women approached in the afternoon to ask the cost of a trip along one popular route. Zhang stepped forward, saying with a smile: "We used to charge 480 yuan for a motorboat from here to the approach bridge and the marine museum. Now you just pay half."
The two women talked it over and then shook their heads, pointing to the vast field of algae.
Zhang said: "See? No one wants to ride, even at half price. I will lose money if I cut fares any further. I have to pay rent, fuel and salaries."
Wang Xian, who operates a fleet of a dozen sea bicycles, simply shut down his business at the third bathing beach.
"There is too much algae. The foot pedals will become entangled if a sea bicycle goes through it," he said.
GET ALGAE UNDER CONTROL
"There are many ways to make the stuff go away, including hauling it in by net with fishing and other boats or eradicating it through chemical method," said Zang Aimin, an executive board member of the Beijing Organizing Committee for the Olympic Games.
The SOA's North China Sea branch experimented with copper sulfate, which fully killed the algae in an enclosed area in 72 hours.
Experiments also showed that under natural conditions, the algae would grow and expand at a daily rate of 20 percent. While inorganic nitrogen and phosphate were consumed in an enclosed environment, the algae would expand at much slower pace.
"So far, we have used only the net hauling method, to avoid damaging the environment," said Zang.
Each day, the city sends more than 10,000 people into the sea on 1,200 vessels. Onshore, 220 vehicles work to weed out the blooming algae.
The city has tried to integrate mechanical and human activity, and sea and land efforts. Soldiers and volunteers were given responsibility zones.
Learning from lessons of slow efficiency in independent operation of fishing and other boats in early June, the city has improved the facilities and methods as it came to the end of the month.
The city developed a technique called "Gong Dou Wang," in which a boat is equipped with a rail on each side, from which hangs a net. As the boat sails into an area densely covered with algae, the nets collect 50 to 60 times more algae than can be scooped up by hand.
"We will equip 300 boats in this way within three days," said Wang Shouxin, deputy director of the Shandong Provincial Oceanic and Fishery Department.
Tow nets have also been widely used. A pair of large boats can collect 15 to 20 tons of algae per hour with such nets.
Fishing boats have also improved their efficiency by gathering algae in nets, then sucking it up with a massive pump, plowing through the tide of algae like a vacuum cleaner.
"Thanks to the improved methods, we are dredging up more algae. We could clean up as many as 21,000 tons of algae a day," said Liu Chenlin, deputy director of the general office of the Qingdao Municipal Government.
Local volunteers show that it is a common aspiration to clear away the algae for a smooth Olympics.
On July 1, after a torrential rain, a great quantity of algae was washed into the sea near Laoshan District, 10 minutes drive to the east of the sailing venue, worsening the situation.
The next day, about 300 residents from the Zhonghan Community, Laoshan District, went to the beach to the south of the sculpture park, answering the call of the community committee. They carried 1,000 rakes.
"We'd have come earlier, but we were afraid of interfering with the work of the professionals," said Wang Junqiang, a community staffer.
A 9-year-old girl, Ma Yakun, was among the enthusiastic volunteers. The third grader took her last final exam for the term in the morning and went to the seashore with her mother at noon.
"I cannot clear as many algae as my mother, but many a little makes a nickel," said Ma, stuffing the algae into plastic sacks with her bare feet.
That afternoon, the volunteers cleared about 30 tons of algae from the shoreline.
BLOCK ALGAE FROM SAILING VENUE
Besides cleaning up the coast, the city has tried other methods to clear the algae from the Olympic competition area.
"We set up four lines of defense for the 50 square kilometer Olympic venue. After days of arduous work, helped by changes in the wind direction and ocean currents, the algae coverage dropped sharply in the venue," said Zang.
To eliminate the algae, the city plans to fence off the venue with oil buffers.
The city experimented with blocking floating algae, using 2,000meters of oil buffers, with satisfactory results, said Zhu Weiguo,a supervision chief with the Qingdao Maritime Affairs Bureau. But Qingdao officials said 32,000 meters of oil buffers would be needed to cordon off the whole venue and prevent the inflow of more algae.
The Ministry of Transport mobilized resources nationwide to help. Nine provinces and municipalities have sent 18,000 meters of buffers, with more on the way. The venue is expected to be fully cordoned off on July 7.
IDEAL FEEDSTUFF FOR FARMS
While loathed by boaters and swimmers, the algae is loved by another group of people -- poultry and sea cucumber farmers.
Sun Facai, a chicken farmer in Shazikou, Qingdao, said algae is rich in carbohydrates, protein, fiber and minerals, making it a great chicken food when dried in the sun and crushed with machines.
Algae could also reduce the cholesterol level in egg yolks, improving egg quality.
Plus, it's free.
"We do not have to pay for it," said Sun. "I employ 10 workers to collect algae on the banks of the sea, and they collect about 20 tons a day. I have stored 100 tons of algae."
Liu Sheng, a sea cucumber farmer, is also among the ranks of algae collectors, as algae is a good feedstuff for marine life, such as sea cucumbers.
Algae may be extensively processed, yielding flavor essence, amino acids and natural pigments, according to the Qingdao Science and Technology Department.
However, the city doesn't have advanced technology to process the algae in this manner, so nearly 200,000 tons of the green stuff have been buried at garbage dumps in the city.
Source: Xinhua
|
Comment
Tell A Friend
Print Format
Save Article