一、我国淡水养殖鱼类的多样性 　　中国国土辽阔，从位于北纬 4°的南沙群岛到北纬 53°的黑龙江漠河，覆盖了热带、亚热带、温带至亚寒带的气候条件，差异悬殊的气候条件既为人工养殖提供了丰富的可供选择的野生种类，同时也对养殖种类的适应性提出了不同的要求。因而构成了 First, China’s freshwater aquaculture diversity China has a vast territory, ranging from the Nansha Islands at latitude 4 ° to the Mohe at Heilongjiang 53 ° N latitude, covering the climatic conditions of tropical, subtropical, temperate to subtropical zones. The climatic conditions of disparity are both It provides a wealth of alternative wild species for farmed species, but also imposes different requirements on the adaptability of cultured species. Thus constituted