【摘要】 研究了河蟹生态育苗池中最常见的糠虾、利氏才女虫幼体 (PLL)、桡足类与河蟹状幼体 (Z)间的关系。结果表明 :糠虾严重影响Z的存活与变态 ,其密度达 3个 /L时可使育苗绝产 ,应彻底杀灭。PLL对Z的危害随其密度的增大而加剧 ,当PLL达 5 0 0个 /L时即严重危害Z1的变态 (变态率为 40 % ,对照组为 80 % ) ;在无轮虫的情况下Z1的变态率更低 (30 % )。Z1可摄食体长小于 0 4mm的PLL ,Z5则完全可以PLL为食而不受其害 ,因此 ,可根据具体条件控制利用PLL。桡足类对Z的影响主要是干扰变态 ,以至引起死亡。当桡足类密度达 5 0 0个 /L时 ,Z1的变态率仅为 2 5 % ,因桡足类是Z4 、Z5的饵料生物 ,育苗初期 (Z1～Z2 )要控制其密度 (<1 0 0个 /L)更多还原

【Abstract】 This paper mainly deals with the relations among mysis、 Polydora ligni larva (PLL) copepod and zoea of chinese mitten crab (Eriocheir sinensis) during the crab larvae rearing period in ecological way.The results showed that the zoea survival and metamorphosis rates of the crab reduced significantly when the mysis was at density of 3 ind /L.Destruction to zoea caused by PLL increased along with the increase of density.PLL was seriously harmful to the metamorphosis of Z 1(metamorphosis rate is 40%,80% in control group) The rate of Z ’ 1s metamorphosis was about 30% without rotifers.Z 1 was able to eat the PLL whose length is less than 0 4mm Z 5 can eat any sizes of PLL instead of being eaten by PLL So we can handle and take advantage of PLL under certain conditions.The copepod mainly interferes in the metamorphosis of zoea and causes crab larvae death.The metamorphosis rate of Z 1 was only 25% when the density of copepod was upwards to 500 ind /L.Because the copepod was the natural food of Z 4 and Z 5,we should control its density(<100 ind /L)during rearing incipiency (Z 1～Z 2)更多还原