高盐度海水氮磷营养盐保存技术研究

Study on preservation method of nitrogen and phosphorous in high salinity seawater

采用12种不同方法保存盐度为32的高盐度海水水样中的4种氮磷营养盐(NH3-N、NO2-N、NO3-N、PO4-P),使用FIAstar5000营养盐流动注射分析仪对4种营养盐在9 d保存期内参数值的稳定性进行研究。结果表明,不同保存方法间存在差异,每种营养盐的最佳保存条件不同。9 d试验期内,水样中NH3-N的变化趋势较大,NH3-N和PO4-P的含量呈减小趋势,NO2-N、NO3-N的含量略微上升。水样中加氯仿对氮营养盐(NH3-N、NO2-N、NO3-N)的保存效果较好,加甲醛对磷营养盐(PO4-P)的保存效果较好。综合考虑试验结果的有效性和可操作性,得出了4种营养盐9 d内最适保存条件:常温下加5‰氯仿,NH3-N的保存效果能稳定在80%以上;在-20℃加1‰氯仿时,NO3-N的保存效果最好,9 d内稳定性都在95%以上;在-20℃或4℃下加5‰或1‰氯仿,NO2-N在9 d内都能稳定在95%以上;4℃下加5‰甲醛时,PO4-P的保存效果最好。

In this paper, 12 different preservation methods were used to save 4 kinds of nitrogen and phosphorus nutrients （NH3-N, NO2-N, NO3-N, PO4-P） in high salinity sea water of salinity 32. We studied the parameter values stability of 4 kinds of nutrients in 9 days storage using FIAstar5000 nutrient flow injection analyzer. The results showed that there were obvious differences among different preservation methods, the best preservation conditions of each nutrient was different. In 9 days experimental period, NH3-N in water samples had a large change tend, the NH4-N and PO4-P content presented a trend of decrease, while NOz-N and NO3-N content slightly rose. When chloroform was added into water samples, it was very good for the preservation of nitrogen nutrient （NH3-N, NO2-N and NO3-N）; when formaldehyde was added, it was good for the preservation of phosphorus nutrient （PO4-P）. Considered the effectiveness and operability of the experiment results, we obtained the optimal preservation condition of the 4 kinds of nutrient in 9 days. When 5%0 chloroform was added into water samples, the stability of NH3-N could be controlled more than 80%; when 1‰ chloroform was added into water samples and the water samples were stored at -20℃, the stability of NO3-N could be over 95%; when 5‰ chloroform was added at -20℃ or 1%o chloroform was added at 4℃ into water samples, the NOz-N could be more than 95%; when 5‰ formaldehyde was added at 4℃, it was the best method to save POa-P.