The effect of un-ionized ammonia on the population growth of the rotifer in mass culture
The effect of un-ionized ammonia on the population growth of the rotifer in mass culture
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非离子氨对大规模培养轮虫种群增长的影响
DOI：
10.2331/suisan.52.1509
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发表时间：
1986
影响因子：
0.4
通讯作者：
K. Hirayama
中科院分区：
文献类型：
--
作者：
Jingjin Yu;K. Hirayama
在规模化培养池中，褶皱臂尾轮虫的无机物浓度。1984年4月至7月，在长崎县水产研究所水产养殖研究实验室每天测量氮化合物、pH、水温和比重。轮虫密度随非离子氨氮(NH3-N)浓度的增加而降低。NH3-N最高浓度为3.6ppm。只有在pH为7.3-7.8时，才能观察到轮虫密度在150棒/毫升以上。NH3-N对轮虫的急性毒性试验表明，在23℃条件下，24小时的LC_(50)值为17.0ppm。慢性毒性试验表明，当NH3-N浓度降低50%时，轮虫的种群增长和繁殖量分别为13.2和7.8ppm。将种群内禀增长率和净繁殖率降低L%的浓度作为NH_3-N的“无效应”浓度。据估计，它们分别为2.1ppm和2.4ppm。大规模培养和毒性试验结果表明，高浓度的NH3-n可能是影响轮虫数量增加的制约因素之一。
In mass culture tanks for the rotifer Brachionus plicatilis, the concentrations of inorganic. nitrogen compounds, pH, water temperature and specific gravity were measured daily at the Aqua-culture Research Laboratory of Nagasaki Prefectural Institute of Fisheries from April to July, 1984. The rotifer density decreased with an increased concentration of un-ionized ammonia nitrogen (NH3-N). The highest concentration of NH3-N observed was 3.6ppm. The rotifer densities above 150 rods./ml were observed, only when the pH ranged from 7.3-7.8. Acute toxicity test of NH3-N to rotifers showed that 24h LC50 value was 17.0ppm at 23°C. Chronic toxicity test showed that concentrations of NH3-N at which the population growth and the reproduction reduced by 50% of the controls were 13.2 and 7.8ppm, respectively. The concentrations at which the intrinsic rate of population growth and the net reproduction rate were reduced by l% of those of the control, were adopted as the “no-effect” concentration of NH3-N. They were estimated as 2.1 and 2.4ppm, respectively. The results from mass culture and toxicity tests showed that higher concentration of NH3-Nmight be one of restrictive factors affecting the increase of the rotifer.