合浦珠母贝代谢产物对异枝麒麟菜生长的促进作用

THE GROWTH PROMOTING EFFECT OF METABOLITES OF PINCTADA MARTENSI ON KAPPAPHYCUS ALVAREZII

于1995年4月间在海南省三亚市、陵水县分别采集合浦珠母贝和异枝麒麟菜并进行混养实验，测定贝释放的三氮（NH4－N，NO3－N，NO2－N）以及藻类对贝释放的三氮的吸收及其生长，以期探讨合浦珠母贝代谢产物促进异枝麒麟菜生长的原因。结果表明，贝释放物中以NH4－N为主，NO3－N次之，NO2－N含量较少；藻对三氮的吸收亦依此顺序递减。实验组藻体的生长速率明显高于对照组的，在模拟实验组中，通过加入无机氮使水体中NH4—N，NO3－N，NO2－N浓度与实验组贝释放后的浓度相同，藻体生点速率接近实验组的。本结果直接证明了贝释放的三氮是促进藻体快速生长的主要原因。另一方面，藻类吸收了贝类代谢产物，也优化了养殖区的生态环境。

In April 1995, a study on the effect of metabolites released from Pearloyster Pinctada martensi (collected from the experimental site) on the growth of redalga Kopaphycus alvarezii (collected from Lingshui County, Hainan lsland) wasconducted at the Hainan Tropic Marine Biology Experimental Station, ChineseAcademy of Sciences. Laboratory study and in situ experiments were carried out. Inthe laboratory experiment pearl oysters were placed for 6 hours in sterilized seawaterin a glass container and the concentrations of NH4-N, NO3 -N and NO2-N wereanalysed after the removal of the Pearl oysters. The alga was then placed for 1h inthe Pearl oyster treated seawater. After removal of the alga the concentration of thethree nitrides were analyzed again. The alga was placed in cages suspended under afloating raft in the open sea and increase in fresh weight was measured. Theexperiments were repeated on day 1, 4, 7, 10 and 13. The experimental resultsshowed that after one day in the Pearl oyster treated seawater, NH4-N was the maincomponent (0.244mmol / L), NO3-N the secondary (0.188 mm0l / L) and NO2-N thesmallest (8.8 x 10 ) mmol / L), and that their absorption by alga were in the order26; 15; 1. The growth rate of test alga was much higher than that of the control. Inthe simulation expenment. because the added amount of the three nitrides were equalto the amounts naturally released by pearI oysters, their growth rate approached that ofalga in the experimental group. These resultS showed that the three nitrides releasedby Pearl oyster were the main cause of the high growth rate of the alga. K.alvareziican therefore be used as a nitrogenous waste remover in peari oyster farm to improvethe seawatCr quality and pearl oyster production. Since the number of sites favorableto aquacultUre are limited, it is advantageous to find ways of increasing producivitywithin existing sites. The solution to conflicting demands between development ofhighdensity mariculture and protection of a marine environment may rely on cultureand the interaction between primary producers and consumers.