随着我国国民经济的高速发展及农业结构的调整，我国水产养殖业得到了迅猛发展。我国淡水养殖面积有６００万公顷，海水养殖面积有２０万公顷。淡水养殖面积和产量均为世界第一，并且饲养的品种也已逐步向精养的高档种类转变，虾、蟹、鳖及高档鱼类种类所占的比例越来越大。但 With the rapid development of our national economy and the adjustment of agricultural structure, aquaculture in our country has witnessed rapid development. There are 6 million hectares of freshwater aquaculture in our country and 200,000 hectares of aquaculture area. Freshwater aquaculture area and output are the world’s first, and the breed has also been gradually transformed into intensive high-end species, shrimp, crab, turtle and high-end fish species account for an increasing proportion. but