培养淡水浮游硅藻所需的最适氮磷比

The optimal N/P of the freshwater pelagic diatom

在以氮为 0 .5 mg· kg-1的条件下对淡水浮游硅藻的最适氮磷比进行了 3次试验。第一次N/P定为 6 /1、7/1和 8/1 ,溶于自来水进行 5 d培养后用碘液固定 ;稀释 1 0倍后用浮游植物计数框记数 5 0个视野的平均结果分别为 1 0 5 .6、1 75 .8和 1 2 5 .6个。第二次根据第一次的结果 ,N/P定为 7.2∶ 1、7.4∶ 1及 7.6∶ 1 ;记数结果分别为 3 76 .5、3 93 .2及 3 5 1 .3。第三次 N/P为 7.2∶ 1、7.3∶ 1及 7.4∶ 1 ;计算结果为 2 5 8.7、2 78.7及 2 77.3。试验结果表明 :硅藻的最适氮磷比为 7.3∶ 1。

To discover the optimal ratio of nitrogen to phosphorous for freshwater pelagic diatom(Bacillariophyta),we take 3 times trials on condition that the concentration of N is 0.5 mg/kg. During the first trial,we design the ratio of N to P respectively 6 to 1,7 to 1 and 8 to 1.After dissolving the two reagents in the running water, then adding diatom in it, cultivating 5 days later,using iodine solution fixing diatom,diluting it 10 times, taking count of it with phytoplankton counter frame. The average quantity in the 50 eyeshots is respectively 105.6,175.8 and 126.5..According to the result of the first trial, in the second trial the proportion of N to P is determined 7.2 to 1,7.4 to 1 and 7.6 to 1,the counting result is respectively 376.5,393.2 and 351.3.Through the same means, we determine the ratio of N to P 7.2 to 1,7.3 to 1 and 7.4 to 1 in the third,the result is respectively 258.7, 278.7 and 177.3.Through the 3 times experiments above the result indicates the most suitable proportion of N to P for is 7.3 to 1.The mensuration of optimal ratio of N to P of diatom lays stable scientific groundwork for reasonable fertilization in aquaculture.