A national standard will be drafted that limits pollutant discharge into the sea as part of a campaign to protect the fragile maritime environment, a top administrator said.

Local regulations in coastal provinces are the only code of conduct currently covering marine pollution and this underlines the urgency of a national standard, Liu Cigui, head of the State Oceanic Administration (SOA), told China Daily.

"A healthy marine bio-system depends, largely, on reducing the amount of pollutants from the land," Liu said.

"Polluting industrial projects must be prohibited on our coasts."

Cleaning up the mess and protecting coastal areas will not be an easy task as industrial and domestic discharge has taken a toll.

About 147,000 sq km of coastal water, almost the size of the US state of Florida, failed to meet national clear water standards in 2009, an increase of 7.3 percent from the previous year, according to a report released last year by the SOA.

About 75 percent of the nearly 500 coastal monitoring stations reported excessive pollutants in 2009, with 14 million tons of heavy metals discharged into the sea, a year-on-year increase of 16 percent, the report said.

In Fujian province, about 80 percent of marine pollutants came from industrial and household waste, according to a report on the province's ocean environment issued last September.

Pollutants discharged into the ocean without proper treatment pose hazards to the marine environment, Liu said.

Heavy metals are one of the major marine pollutants as industries have sprouted along coastal regions.

"Only by setting strict standards and conducting feasibility studies for industrial projects can we keep damage to a minimum," Liu said.

The 12th Five-Year Plan (2011-2015), approved by the National People's Congress, the top legislature, in early March, laid out measures to strengthen pollution management in coastal areas.

The measures aim to prevent over-exploitation of marine resources and stop excessive land reclamation. They also call for uninhabited islands to be put to better use and boosting capabilities to respond to marine emergencies.

Liu said the SOA will issue a list of all China's islands next month.

A five-year survey revealed that 806 islands had disappeared during that period because of land reclamation and erosion, Xia Xiaoming, a researcher with the Second Institute of Oceanography of the SOA, said.

He called for curbs to be introduced on any activity that threatened islands.