光周期和光照强度对克氏双锯鱼仔鱼存活、生长和发育的影响

采用实验生态学的方法,研究了光周期和光照强度对克氏双锯鱼(Amphiprion clarkii)仔鱼存活、生长和发育的影响.结果表明,除了全黑实验组外,光周期对克氏双锯鱼仔鱼成活率无显著影响(P>0.05),但光照强度对仔鱼成活率具有重要影响,过强或过弱的光照都不利于仔鱼成活,其中光照强度在100-1000 Lx时成活率较高(47.7-56.0%).光周期和光照强度对克氏双锯鱼仔鱼发育变态均有重要影响.仔鱼发育速率随光周期延长而加快,当光周期为16L:8D时达最大值(0.081±0.002);光照强度在500Lx以下时,随着光照强度的增加,仔鱼发育速率加快,而光照强度达2000 Lx时发育速率显著下降(P<0.05).仔鱼生长速率也随光周期延长而加快;仔鱼在相对较弱的光照强度(100-1000 Lx)获得较高的日生长率(全长),而光照强度太弱(<100 Lx)或者太强(>1000 Lx)均对其生长有较强的负作用.

Effects of Light on Survival,Development and Growth of Larvae of Amphiprion clarkii

Based on the methodology of experimental ecology,the present study examined the effects of light（ include both duration and intensity） on larval survival,growth and development of Yellowtail clownfish Amphiprion clarkii. Results showed that light duration did not influence the larval survival rate of A. clarkii significantly（ p 〉0. 05）,except the experimental group of 24-h dark. The light intensity,however,influenced the larval survival rate; the light intensities between 100 and 1000 Lx gave high larval survival rates of 47. 7-56.0%,and lower or higher light intensities had negative impacts on larval survival. Light duration and light intensity had significantly impacts on larval development and metamorphosis of A. clarkii. The developmental rate increased with the extension of light duration; the light duration of 16L： 8D gave the highest developmental rate of（ 0. 081 ± 0. 002）. When light intensity 〈500 Lx,the larval developmental rate increased with the increase of light intensity; however,the developmental rate decreased significantly when light intensity reached2000 Lx（ P〈 0. 05）. The larval growth rate increased with the extension of light duration. At low light intensities of 100-1000 Lx,larvae had high daily growth rate（ total length）; light intensity outside the range（ 〈100 Lx or 〉1000 Lx） had negative impact on larval growth rate.