温度和干露对单环刺螠幼螠成活率的影响

Effect of temperature and dry exposure on survival rate of juvenile Urechis unicinctus

为探讨温度及干露条件对单环刺螠(Urechis unicinctus)苗种运输成活率的影响,采用平均体重规格为(1.6±0.1)g的幼螠,在18℃下设置海水组和干露组,海水组幼螠密度100个/L,干露组幼螠密度为0.9、1.8、2.7个/cm^(2);同时设置9、14、18℃三个温度下的干露试验。试验初期每6 h观察存活状况,36 h后每3 h观察存活情况。结果表明:18℃条件下,干露试验组无论密度大小,幼螠均在39 h出现死亡,51 h全部死亡,海水组幼螠成活率100%;9℃干露组幼螠存活状况优于14℃和18℃组,但在39 h后也出现死亡。

In order to investigate the effects of temperature and dry exposure on the survival rate of juvenile Urechis unicinctus,juvenile Urechis unicinctus with average initial body weight of(1.6±0.1)g were tested.At 18℃,the density of Urechis unicinctus in seawater group and dry exposure group was 100 ind./L.The density of Urechis unicinctus in dry exposure group was 0.9,1.8 and 2.7 ind./cm^(2).At the same time,the dry exposure test was set at 9,14℃and 18℃,survival rate was observed every 6 h at the beginning of the test and every 3 h after 36 h.The results showed that,at 18℃,no matter the density of the dry exposure test group,the larvae died at 39 h,and all died at 51 h,survival rate in the seawater group was 100%.Survival rate of juvenile Urechis unicinctus in the 9℃dry exposure group was better than that in the 14℃and 18℃groups,but death of juvenile Urechis unicinctus occurred 39 h later.