Effects of temperature,salinity and sediment on the growth and survival of Solen grandis Dunker juveniles

We studied the growth and survival of Solen grandis Dunker juveniles reared at different laboratory conditions,namely 10 temperature grades from 6 to 36℃ at salinity 21.4‰,10 salinity grades from 4‰ to 40‰ at temperatures from 21.6 to 28.6℃,and three depth grades from 5 to 30mm formed by four different kinds of sediments(fine silt,fine sand,coarse sand,and mixture of coarse sand and fine silt).The results are as follows.(1) The suitable temperature under salinity of 21.4‰ for juvenile growth and survival ranged from 6 to 30℃,and the optimal temperature ranged from 21 to 30℃.Under the suitable temperature,the growth and survival rates increased with the increase of temperature;the maximum survival rate was 88% at 21℃,and the maximum daily growth rate was 1.82% at 30℃.(2) The suitable salinity under temperature from 21.6 to 28.6℃ for juvenile growth and survival ranged from 20‰ to 32‰,and the optimal salinity ranged from 20‰ to 28‰.Under the suitable salinity,increasing salinity resulted in an increase of both growth and survival rates;the maximum survival rate was 85% under the salinity of 20‰ and the maximum daily growth rate was 1.72% under the salinity of 24‰.(3) The substrate and sandy diameter had no effects on the growth and survival rates of juveniles,but the depth of sediment had significant impact on the growth and survival rates.The growth and survival rates of the groups under 10 and 30mm were higher than those under 5mm.