Local authorities and residents in Qingdao City have been struggling to remove a large mass of green algae that has come ashore on the beaches of the popular coastal tourist destination in east China's Shandong Province.

Police officers from Huangdao frontier guard bridgade clean green algae along the beach in Qingdao, east China's Shandong province, June 27, 2010. As large amounts of the algae are washing ashore, the city implemented a series of plans to prevent plague triggered by the algae. [Xinhua]

At a beach on Xuejia Island in Qingdao, the foul-smelling green algae, called enteromorpha by scientists, has formed a strip which is reported to be two to three meters wide and hundreds of meters long.

The North China Sea Branch (NCSB) of the State Oceanic Administration said Monday that the floating green algae covered a 400-square-km area in the waters to the south of Qingdao.

The government staff, tourism companies and coastal residents began cleaning the green algae as soon as it was spotted on the beach Friday, said Sun Hongbin, who operates a motorboat-rental business on the beach.

The local government has dispatched 66 vessels to clean the algae and four other boats to monitor the movement of the algae mass.

A net had also been set up off shore to block the incoming algae as hundreds of people participated in the clean-up efforts either on shore or at sea, Sun said.

The green algae which has been removed would be used to feed livestock or be buried to fertilize farmland, according to officials.

Due to the spreading green algae, the number of beach tourists has fallen from more than 5,000 to just several hundred, Sun said. "A boy became entangled in the algae off shore Saturday and it almost killed him," Sun said.

Though not poisonous and with no affect on water quality, the algae can consume large amounts of oxygen, threatening marine life.

Zhao Peng, an official with the border police station on Xuejia Island, said the algae's possible damage to sea farming must be prevented. "In 2008, a similar green algae mass killed a lot of scallops, fish and abalones, causing huge economic losses to local fishermen," he said.

The NCSB first detected the green algae mass in the sea off the coast of Rizhao City in Shandong June 14 and has monitored the algae mass as it continued to drift north.

The algae is expected to continue moving northward and come ashore along the northern coastlines, said a spokeswoman for the NCSB.

Green algae was discovered in the Yellow Sea in 2007. Local residents and soldiers removed tens of thousands of tonnes of the algae in 2008 prior to the Beijing Olympics' sailing competitions in Qingdao.