Ministry of Agriculture and Rural Affairs： Scientific aquaculture can purify the ecological environment.

Conference site (Tang Shiying/photo)

Cctv news(Reporter Tang Shiying) At 10: 00 a.m. on February 15th, the State Council Press Office held a press conference. Yu Kangzhen, Vice Minister of Agriculture and Rural Affairs, and Zhang Xianliang, Director of the Fisheries Bureau of the Ministry of Agriculture and Rural Affairs, introduced the "Several Opinions on Accelerating the Green Development of Aquaculture" and answered questions from reporters.　

At the meeting, a reporter asked: "In recent years, some voices in the society have suggested that aquaculture has some negative effects on the environment. Excuse me, how does the Ministry of Agriculture and Rural Affairs view this issue? "

"We did learn that in some places, the relationship between aquaculture and water ecological environment was not handled very well, and aquaculture polluted the environment. Is it true that all kinds and methods of aquaculture will pollute the water ecological environment? Need scientific analysis. " Yu Kangzhen said that not all aquaculture varieties and farming methods will have a negative impact on the aquatic ecological environment, only high-density and unreasonable feeding farming methods will have a greater impact on the environment, and scientific and reasonable farming methods will not cause pollution to the environment. On the contrary, scientific and reasonable farming methods can also purify and repair the water ecological environment.

Yu Kangzhen introduced that according to the Bulletin of the First National Pollution Source Survey, aquaculture emissions are calculated by chemical oxygen demand and ammonia nitrogen, accounting for 4% of agricultural emissions. Most pollutants in aquaculture are organic substances such as nitrogen and phosphorus, which mainly cause eutrophication of water environment and have little impact on water body as a whole. In addition, filter-feeding fish such as shellfish algae in marine culture and silver carp and bighead carp in freshwater culture in China are all non-feeding aquaculture varieties. Among them, shellfish algae account for 83% of the total amount of marine aquaculture, and filter-feeding silver carp and bighead carp account for 25% of the total amount of freshwater aquaculture. These cultured varieties have good purification and restoration effects on the environment. It is estimated that in 2016, only silver carp and bighead carp culture can eliminate about 370,000 tons of nitrogen and 140,000 tons of phosphorus in water.　

The results of a consulting research project of China Academy of Engineering show that the algae culture of marine shellfish has an efficient "carbon fixation" function. Yu Kangzhen said that only marine shellfish culture can remove more than 1.2 million tons of carbon every year. "The contribution of marine shellfish culture in China to reducing atmospheric carbon dioxide is enormous. To make a metaphor, it is equivalent to afforestation of 500,000 hectares per year, and the ecological benefits are remarkable. "