水生生物的一个重要特点是能够经由体表吸收水中的溶解物质。许多资料表明,鱼类能从周围水体中吸收某些营养元素而使之维持平衡。毒物、药物及其它物质也能由水中渗入鱼体。计算鱼体的物质平衡,重要的是了解鱼类对水中溶解物质的吸收率,即水中所含物质有多大比例渗入鱼体。 An important feature of aquatic organisms is the ability to absorb dissolved substances in water through the body surface. Many sources indicate that fish retain their balance by absorbing certain nutrients from the surrounding water. Poisons, drugs and other substances can also penetrate the fish from the water. Calculate the material balance of fish, it is important to understand the fish’s absorption of dissolved substances in water, that is, what percentage of the water contained in the body into the fish.