【作者】 王珺；

【导师】 陈国华；

【作者基本信息】 海南大学 ， 水产养殖学， 2009， 硕士

【摘要】 石斑鱼育苗中,常因水质变坏（某些有害物质积累）,造成育苗的失败。水质变坏的解决办法通常是换水,但在育苗早期由于石斑鱼苗个体小、体质弱,换水容易使鱼苗粘在筛绢网上死去,或是换水造成水质大幅度变化而影响鱼苗成活率等。为此,希望在育苗的前20天内,不需换水而又能维持水质的正常和稳定。为了解决这个问题,育苗实践中有二条解决途径:一是利用单细胞藻类吸收育苗池中的有害物质,保持水质的稳定。二是定时定量加入微生物制剂,利用微生物分解残饵、排泄废物、动植物残体,保持水质稳定。同时,这二种方法都使育苗生态系统的食物链更加复杂,从而增加水体的稳定性,丰富了鱼苗的饵料。本研究即是按这个思路设计,从定量角度了解加入微藻或加入EM菌和虾片对育苗系统生态因子的影响。主要研究结果如下:1.对理化因子的影响。藻类进行光合作用过程中,吸收CO₂,使pH升高;当藻类在育苗池中生长良好时,有降低亚硝酸盐和氨氮的作用。育苗水体中加入EM菌和虾片,使pH降低;EM菌降低亚硝酸盐、氨氮、无机磷的作用明显。2.对水中浮游植物、浮游动物的影响。加入EM菌和虾片,能使水中浮游植物、浮游动物的种类和数量显著增加。3.对不同粒级浮游生物的呼吸率及初级生产力的影响。加EM菌和虾片的菌1组,水体中小型、微型及超微型浮游生物的平均呼吸率分别为0.012,0.177及0.347mg/（dm³·d）,平均毛生产率分别为0.006,0.027及0.052mg/（dm³·d）;菌2的育苗生态系中,小型、微型及超微型浮游生物的平均呼吸率分别为0.009,0.226及0.433mg/（dm³·d）,平均毛生产率分别0.055,0.033及0.054mg/（dm³·d）。加微藻的藻1组,水体中小型、微型及超微型浮游生物的平均呼吸率分别为0.024,0.031及0.260mg/（dm³·d）,平均毛生产率分别为0.034,0.047及0.124mg/（dm³·d）;藻2组,微型及超微型浮游生物的平均呼吸率分别为0.089,0.067及0.336mg/（dm³·d）,浮游植物的平均毛生产率分别为0.084,0.135及0.191mg/（dm³·d）。4.对原生动物的种群增长和生产量的影响。加入EM菌和虾片的菌2组,原生动物生长良好,其生物量和生产量均显著高于加入微藻的藻2组。加入EM菌和虾片的育苗池,其原生动物优势种为中縊虫、旋回侠盗虫和太阳虫,种群的增长率（r）分别为0.008～0.043、0.009～0.049和0.016～0.036/hr;加单胞藻的育苗池,其原生动物优势种有中縊虫和周毛虫,种群增长率（r）分别为0.005～0.021和0.007～0.008/hr。加菌育苗池和加藻育苗池原位试验瓶中原生动物累积日均产量分别为736.48和46.91mg/m³·d。日P/B系数（周转率）分别为1.38和0.70。更多还原

【Abstract】 Many artificial larval rearing of grouper failed due to the deterioration of water quality （the accumulation of harmful substance）. The conventional solution was to refresh water. However, the early fries could mass mortality for the ecosystem changing and the screen cloth adhibiting during the water refreshing process. So, the stabilization of the water quality was expected in the first 20 days. Two strategies could be choiced in the larval rearing productive practice. One was to use unicellular algae to keep the stabilization of the water quality, the algae can absorb the harmful substance in the rearing pool. The other was to add shrimp chip and living bacteria timingly and quantitatively, because living bacteria can breakdown the residual bait, excreta, residues of animal and plant, and noxious gas（ammonia, hydrogen sulfide etc.）. This article quantitatively analyzed the changes of ecological factors in two industrialized breeding ecosystem. The main results were shown below:1. Influences on physical and chemical factors in water. The results were as following: when the photosynthesis was in process, absorbion of the CO₂ by algae raised the pH of the water; algae could decrease the nitrite content of water when they grew well in the rearing pool; algae also reduced the content of ammonia nitrogen significantly. Adding effective macrobes （EM） and shrimp to the rearing water could reduce the pH; EM could also reduce the content of nitrite, ammonia nitrogen, and inorganic phosphate.2. Influence on phytoplankton and zooplankton. The results were as following: adding EM and shrimp could significantly increase both the species number and quantities of phytoplankton and zooplankton in water.3. Influence on the respiration rate and primary productivity of plankton in different fraction. The results were as following: in the ecosystem added with EM 1, the mean respiration rate of minitype, microscale and ultramicroscale were 0.012, 0.177 and 0.347mg/（dm³·d） respectively, and the mean primary productivity were 0.006, 0.027 and 0.052mg/（dm³·d） respectively; in the ecosystem added with EM 2, the mean respiration rate of minitype, microscale and ultramicroscale were 0.009, 0.226 and 0.433mg/（dm³·d） respectively, and the mean primary productivity were 0.055, 0.033 and 0.054mg/（dm³·d） respectively; in the ecosystem added with microalgae 1, the mean respiration rate of minitype, microscale and ultramicroscale were 0.024, 0.031 and 0.260mg/（dm³·d） respectively, and the mean primary productivity were 0.034, 0.047and 0.124mg/（dm³·d） respectively; in the ecosystem added with microalgae 2, the mean respiration rate of minitype, microscale and ultramicroscale were 0.089, 0.067 and 0.336mg/（dm³·d） respectively, and the mean primary productivity were 0.084, 0.135 and 0.191mg/（dm³·d） respectively.4. Influence on the population growth and productivity of protozoa. The results were as following: in the rearing pool added with bacteria, the protozoa grow well, the biomass and productivity were higher than the pool added with algae. In the rearing pool added with bacteria, the mean population growthrate of the main dominant species such as Gymnodinium coeruleum、Mesodinium、Strobilidium gyrans Stokes and Actinophrys sol were 0.013～0.067、0.008～0.043、0.009～0.049 and 0.016～0.036/hr respectively; in the pool added with microalgae, the mean population growth rate of the main dominant species such as Mesodinium and Cyclidium Litomesum Stoke were 0.005～0.021 and 0.007～0.008/hr respectively. Measured by the in-situ experimental bottle test, the protozoa cumulation productivity were 736.48 mg/m³·d and 46.91mg/m³·d respectively, and the P/B were 1.38 and 0.70 respectively.更多还原