Effects of total ammonia nitrogen content and pH on burrowing of juvenile “Zebra 2” strain of Manila clam Ruditapes philippinarum
MA Qianying1, YANG Feng1,2, HUO Zhongming1,2, ZHAO Wen1, YAN Xiwu1,2*
1.College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China; 2.Engineering Research Center of Shellfish Culture and Breeding in Liaoning Province, Dalian 116023, China
Abstract: The effects of total ammonia nitrogen (TAN) concentration and pH on burrowing of “Zebra 2” strain of Manila clam Ruditapesphilippinarum were investigated in a laboratory. The “Zebra 2” strain with shell length of (4.78±0.60)mm were held in a 2 L polyethylene bucket with 5 cm sand at bottom and 15 cm depth water and exposed to total ammonia nitrogen concentration of 0.12 (control), 0.51, 1.03, 1.64, 2.93, 5.93, 12.30, 28.00, and 54.90 mg/L prepared by reagent ammonium chloride at water temperature of 20.7 ℃ and pH of 8.12 or pH values of 7.00, 7.31, 7.55, 7.77, 8.15, 8.27, 8.54, 8.81 and 9.09 at water temperature of 27.1 ℃ for 24 h to probe into the effects of total ammonia nitrogen (TAN) concentration and pH regulated by NaOH and HCl on burrowing of “Zebra 2” strain. The results showed that no significant effect on juvenile vertical shell ET5 (The time required for 5% of the tested juveniles to fall on the surface of the sand to the erection of the shell)(P>0.05) was found at TAN concentration of ≤54.90 mg/L, and that the maximum acceptable toxicant concentration (MATC) of vertical shell ET50， and burrowing ET50 (The time required for 50% of the tested juveniles to be fully burrowed into the sediment) was 28.00-54.90 mg/L, and that ET100 (The time required for 100% of the tested juveniles to be fully burrowed into the sediment)was 0.51-1.03 mg/L, with the MATC of 5.93-12.30 mg/L for 24 h burrowing rate. The “Zebra 2” juveniles were all buried in the sand at 27.1 ℃, 22.8 salinity, and pH from 7.00 to 9.09, with different speed of burrowing at different pH values. No significant effect on the ET5 of the juvenile vertical shell was observed at pH from 7.00 to 9.09, no impact on the vertical shell ET50 at range of 7.55-9.09, no impact on the ET50 of the buried sand at pH range of 7.31-9.09 and no effect on the ET100 of the buried sand at pH range of 7.31-8.27. No obvious effect on the 24 h burrowing rate was found at pH range of 7.00-9.09. In conclusion, the “Zebra 2” clam juveniles had best ET100 at TAN of 0.12-0.51 mg/L or pH 7.31-8.27 without significant effect on the 24 h burrowing rate at pH 7.00-9.09, while TAN≥28.00 mg/L resulted in a significant decrease in the 24 h burrowing rate.
马倩颖, 杨凤, 霍忠明, 赵雯, 闫喜武, . 总氨态氮和pH对菲律宾蛤仔“斑马蛤2号”品系幼贝潜沙的影响[J]. 大连海洋大学学报, 2021, 36(2): 289-294.
MA Qianying, YANG Feng, HUO Zhongming, ZHAO Wen, YAN Xiwu, . Effects of total ammonia nitrogen content and pH on burrowing of juvenile “Zebra 2” strain of Manila clam Ruditapes philippinarum. Journal of Dalian Ocean University, 2021, 36(2): 289-294.
2021, Vol. 36 
