不同光照、温度及不同规格海蜇耗氧率和排氨率的测定

试验在密闭(盐度25.1,pH 7.9~8.1)条件下进行,溶氧量和氨氮量分别采用Winkler法和纳氏试剂法测定。分析不同规格海蜇耗氧率和排氨率时,得出体质量(m)与伞径(D)的关系式为:m=0.0003D2-0.0007D+0.0427,r2=0.9913。幼蜇伞径从7 mm到35 mm,其耗氧率(OCR)和排氨率(AER)均随着伞径的增大而不断降低,分别经回归分析得到曲线:OCR=0.0063D2-0.3531D+6.1533,r2=0.9751和AER=0.4221D2-26.585D+518.83,r2=0.9587。光照影响试验结果表明:各组别光照下的耗氧率、排氨率均显著大于黑暗条件(P<0.01)。分析结果表明,只有20℃和25℃耗氧率差异不显著(P>0.05),而其余各温度间的耗氧率差异均显著(P<0.05);15℃与25℃,20℃与25℃之间排氨率差异不显著(P>0.05),而升温至30℃时,幼蜇代谢明显加快,尤其是排氨率上升较快,与其余各温度间的排氨率差异均极显著(P<0.01)。对幼蜇在光照和黑暗条件下的窒息点进行了测定,发现溶氧小于0.45 mg/L时,试验所采用的伞径为15 mm的幼...

Oxygen Consumption and Ammonia Excretion in Jellyfish Rhopilema esculenta with Various Sizes under Different Illumination and Temperature

Oxygen consumption and ammonia excretion were determined by the Winkler method and the Nessler's reagent method in juvenile jellyfish Rhopilema esculenta with various sizes under different ambient illumination, pH 7.9～8.1 and salinity of 25.1. The relationship between dry weight(m)and the bell diameter(D)was found to be represented as the equation:m=0.0003 D~2-0.0007 D+0.0427, r~2=0.9913. There was a negative regression function among oxygen consumption rate(OCR), ammonia excretion rate(AER)and the bell diameter(D):OCR=0.0063 D~2-0.3531 D+6.1533, r~2=0.9751; AER=0.4221 D~2-26.585 D+518.83, r~2= 0.9587. The juvenile jellyfish had significantly greater OCR and AER under light than under darkness(P＜0.01). The OCR and AER showed a tendency to increase with the increase in water temperature. The significant increases in AER was only found in 30 ℃ group and other three groups(P＜0.01)and the significant increases in OCR were observed in the high water temperature groups except from the 20 ℃ group and the 25 ℃ group(P＜0.05). The asphyxia was found at the dissolved oxygen concentration of 0.45 mg/L for the juvenile jellyfish with bell diameter of 15 mm under light than under darkness.