【摘要】 报道了淡水浮游硅藻所需的最适氮磷值 ,试验分 2个阶段。第 1阶段将氮定为 0 .5 0 μg/ g,把氮磷比设为 6 / 1,7/ 1和 8/ 1,溶于自来水进行 5 d培养后用碘液固定 ,然后稀释 10倍用浮游植物计数框记数 5 0个视野 ,根据结果进一步试验得出最适的氮磷比为 7.3/ 1。第 2阶段在第 1阶段的基础上 ,首先将氮的浓度设为 0 .34 ,1.17及 2 .0 0 μg/ g,培养后固定、稀释、计数 ,根据结果进一步预试验得出氮的最适需求量在 1.5 9～ 1.80 μg/ g;氮为 1.5 9,1. 70及 1.80 μg/ g时 ,淡水浮游硅藻的数量分别为 (2 80± 9.3) ,(30 4.7± 4.8)及 (2 90 .0± 5 .6 )个 ,对照组为(188.5± 9.5 )个。结果表明 :氮为 1.70 μg/ g,磷为 0 .2 33μg/ g是淡水浮游硅藻的最适需求量。更多还原

【Abstract】 The experiment was divided into two phases.In the first phase,the concentration of nitrogen was set as 0.50 μg/g,at first,the ratio of N to P is 6/1,7/1 and 8/1 respectively.After dissolving the two reagents in the running water,diatom(Bacillariophyta) was added into it,cultivating for 5 days,then using iodine solution to fix it,diluting it by 10 times,then took count of it with phytoplankton counter frame in the 50 eyeshots,according to the result,further proceeding was made.The result indicates the optimal ratio of N to P is 7.3/1.The second phase was based on the first phase,at first,the concentration of N was set to be 0.34,1.17 and 2.00 μg/g respectively,accordingly determined the concentration of P,then it was cultivated,fixed,diluted,counted.It is concluded the optimal volume of demand of N ranges from 1.59- 1.80 μg/g ;when the concentration of N is 1.59,1.70 and 1.80 μg/g,the number is (280±9.3), (304.7±4.8) and (290±5.6),that of the control group is (188.5±9.5).The result indicates the optimal concentration of N and P for diatom is 1.70 μg/g and 0.233 μg/g respectively.更多还原