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河流、湖泊和水库是地球上淡水资源的重要组成部分。地球上包括冰川在内约有3%的水是淡水。广阔的内陆水域蕴藏着相当重要的鱼类资源,其中有些是定居性的种类,有些是洄游性的种类,这些鱼类资源作为食品的来源和为娱乐(指游钓)提供有价值的渔业。修建水坝、水域污染,以及渔捞过度导致内陆水域鱼类资源下降,尤其是洄游性种类,如鲑鱼、鲱鱼、鲟鱼和鳗鱼等。在这种情况下,通过放流孵化场饲养的鱼种进行人工增殖是恢复资源并保证持续渔业的有效措施。同样,放养在水库和湖泊渔业的发展中
Rivers, lakes and reservoirs are an important part of freshwater resources on Earth. About 3% of the Earth’s water, including glaciers, is fresh water. The vast inland waters contain significant fish stocks, some of which are settled species, some are migratory species that serve as a source of food and provide valuable fisheries for recreation . Dams, water pollution and excessive fishing lead to declines in fish stocks in inland waters, especially migratory species such as salmon, herring, sturgeons and eels. In such cases, artificial propagation of fish species raised through hatchery sheds is an effective measure to restore resources and ensure sustainable fisheries. Likewise, stocking is taking place in the development of reservoirs and lake fisheries