【摘要】 研究了坛紫菜的培育状态、不同氮源及其质量浓度和彩虹明樱蛤与坛紫菜质量比等因素对复合养殖的影响。结果表明,紫菜在苗网上有序分布比自由分散式有更长的生长时间和更高的生长速率。以NO2-N培养的坛紫菜其生长速率最高,4天和7天的生长速率分别达6.13和4.20%/d,高于NH4-N的4.28和2.43%/d及NO3-N的4.72和2.87%/d;不同氮源对培养7天的无机氮变化量和pH值影响较大,其中对第7天的pH值有显著影响(p<0.05)。氮源质量浓度在2.1mg/L水平的坛紫菜生长速率明显高于在1.4mg/L和2.8mg/L水平的坛紫菜生长速率;氮源质量浓度对贝类成活率及培养4天的水体的pH值和DO值影响大,其中对第4天的DO值有显著的影响(p<0.05)。贝藻质量比对坛紫菜生长速率的影响不显著,但对水体的pH值和DO值关系密切,贝类越多,水体的pH值和DO值越低。表明复合养殖中坛紫菜能够促进贝类养殖容量的增加,能够对NO2-N等氮源的吸收利用,从而降低了氨氮对贝类养殖的毒性影响;坛紫菜光合作用吸收了CO2,释放出O2。复合养殖有利于养殖生态系统中O2和CO2保持动态平衡,促进贝藻的生长。更多还原

【Abstract】 The influence of different cultivating situations,different nitrogen fertilizers and their concentration and fresh weight rate of P. haitanensis and Moerella iridescens on the polyculture of P. haitanensis and Moerella iridescens are studied and the growth rate (SGR) of P. haitanensis,survive rate of the shellfish,pH value and DO rate in the water and the changes of total nitrogen concentration in the cultivating water were observed,and thus the effects of nitrogen fertilizers utilized by P. haitanensis were confirmed. The results show that P. haitanensis grew best in NO2-N group,with the SGR of 6.13%/d and 4.20%/d respectively for 4 day group and 7 day group,which is higher than that of NH4-N group (4.28%/d and 2.37%/d) and NO3-N group (4.72%/d and 2.87%/d). The concentration of nitrogen fertilizer of 2.1 mg/L group had higher SGR than 1.4 mg/L and 2.8 mg/L groups,with SGR of 3.42%/d,3.36%/d,2.71%/d respectively,which proves the argument that high nitrogen concentration restrains the algae growth. Nitrogen concentration effects the viability and the pH and DO value,especially the DO of 4 day group(p<0.05). The fresh weight rates of shellfish and algae did not have clear influence on the growth rate of algae,but had great effect on the pH and DO value of the water. The more was the shellfish,the lower the pH,DO and the viability. When the rate of shellfish and algae was bigger than 2,DO value was almost 0,and pH value also decrease remarkably. 3 days later,shellfish almost died completely,and the cultivating water was covered by vellum,and the surface of the algae slightly decayed. Orderly polyculture will be in favor of the growth of Porphyra and shellfish. Porphyra will have longer growth time and higher SGR than free distribution of the young algae on the seed bed. The experiment shows that polyculture would increase the cultivating capability of shellfish. Assimilation of nitrogen by Porphyra decreases the toxicity of ammonia nitrogen to the shellfish. And at the same tome,Porphyra absorbs CO2 and releases O2,which balances the concentration of CO2 and O2 in the ecosystem and helps the growth of both shellfish and algae.更多还原