SHIJIAZHUANG - Provincial fishery authorities told Xinhua how aquaculture in northern Hebei province has been hit by sea ice since January.

Many seashells and sea cucumbers had died from suffocation due to icy conditions in Bohai Sea off Qinghuangdao city, Zhang Zhijun, director of the Fisheries Bureau of Changli county under the jurisdiction of Qinhuangdao, said on Sunday.

Almost all the shallow sea's buoys and an estimated 80 percent of its kelp had been caught up in the ice and carried off, leading to significant economic losses for local fishermen, Zhang explained.

Zhang said it was the second time over the past six years that the region was hit by serious sea ice, a result of low temperature since January.

It is expected that floating sea ice off the cities of Qinghuangdao and Tangshan will not ease in the next few days, said Zhang Wanlei, an engineer for Hebei Marine Forecasts.

On Friday the North China Sea Marine Forecasting Center of the State Oceanic Administration said the maximum outer edge of floating ice over the Liaodong Bay north of Qinhuangdao had shrunk to 57 nautical miles from 74 nautical miles a day earlier.

But the National Meteorological Center warned on Sunday that a new cold wave will sweep China nationwide from Sunday evening to Tuesday, bringing gale winds and plunging temperature by over ten degrees Celsius in some areas in the north.