【摘要】 1 990— 1 999年资源监测表明 :洞庭湖鱼的种类与 70年代基本相同 ,但其组成结构发生较大变化 ,明显以鲤、鲫、鲶、黄颡鱼等湖泊定居性鱼类为主 ,最高达 86.1 % ;“四大家鱼”在渔获物中所占比例不足 1 0 % ,刀鲚等洄游性鱼类已极为罕见 ;90年代渔获量平均为 3.97万t,渔业产量增加 ,但多以 1— 2龄鱼为主 ,补充群体严重不足。水利工程的兴建、泥沙淤积、围垦、污染加剧以及过度捕捞是造成洞庭湖渔业资源衰退的主要原因。更多还原

【Abstract】 The investigations in 1990-1999 show that:the fish species in Dongting Lake are similar to those in 1970s,but the population composition has changed greatly.Most of fishes are the lacustrine fishes including commom carp,crucian carp and Parasilurus sp etc,which take up to 86.1%.The proportion of the four major chinese carps is less than 10%,and the migration fishes( Coilia ectenes etc.)are very scarce.In 1991s the average catch is 39.7 thousand tons.In comparison with the past,the fishery yield increases,but most of fishes are 1-2 year old ones,and the preparing parent fishes are seriously scarce.The main reasons are water engineering,deposit silt,artficial enclosure,water pollution and over catching.更多还原