半叶马尾藻对N、P吸收速率的初步研究

Preliminary Study on Uptake Rate of Nitrogen and Phosphorus by Sargassum hemiphyllum (Turn.) Ag

在实验室条件下研究半叶马尾藻对不同浓度N、P以及不同化合态N的吸收速率。结果显示：不同浓度N、P下,半叶马尾藻对N、P的吸收速率差异有统计学意义（P〈0.05）;半叶马尾藻对N、P的吸收速率随N、P浓度的升高而增加,最大吸收速率出现在N为200μmol/L、P为20μmol/L时,分别为2.397和0.229μmol·g-1·h-1;不同氮磷比条件下,半叶马尾藻对N、P的最大吸收速率出现在氮磷比为10时,在氮磷比为1-30范围内,氮磷比对半叶马尾藻吸收N、P速率的影响有统计学意义（P〈0.05）;不同化合态N对半叶马尾藻吸收N、P速率的影响有统计学意义（P〈0.05）,当NH4＋-N和NO3--N共存时,半叶马尾藻对这2种化合态氮可同时吸收利用,各处理组间,对总无机N的吸收速率差异有统计学意义（P〈0.05）,在c（NO3--N）/c（NH4＋-N）为2∶1和1∶2处有两个峰值,分别为2.036、1.862μmol·g-1·h-1,对P的最大吸收速率均出现在c（NO3--N）/c（NH4＋-N）值为2∶1时,为0.206μmol·g-1·h-1。因此,在粤西沿海半叶马尾藻在消除养殖水域营养盐、防治海水富营养化方面有很大优势。

In order to study the utilization efficiency of N and P by Sargassum hemiphyllum （Turn.） Ag, the uptake rates at different concentrations and N/P combinations were determined under laboratory conditions. The results showed that the uptake rates of N and P were significantly different at different concentrations （P 〈 0.05）, which increased with the increasing concentration of N and P, with the maximum uptake rate of 2.397 and 0.229 gmol/（g h） at concentration of 200 gmol/L- N and 20 lamol/L- P respectively. At different ratio of N to P, the maximum uptake rate of N and P occurred at 10 of N to P; from the value range 1 to 30 of N to P. The effect of different combined of N on uptake rate of N （TN） and P were significantly different （P 〈 0.05）. When NO3--N and NHa＋-N coexisted in the medium, it had effective uptake rates .At the different chemical combination of N,the uptake rate of TN showed a variation tendency of M. The two peak values of 2.036 μmol/（g.h） and 1.862 μmol/（g.h） appeared when the value of NO3--N to NH4＋-N was 2 ： 1 and 1 ： 2, respectively, the maximum uptake rate of P occurred at 2 ： 1 of NO3--N to NH4＋-N were 0.206 μmol/（g.h）. So, Sargassum hemiphyllum （Turn.） Ag has more advantage at eliminating nutrients and preventineutroohication in aauaculture waters.