环境因子对香溪河春季藻类生长影响的模拟实验

摘要

2010年3-5月间,分3批次采集了香溪河水样,以水体营养盐浓度、水温、光强和流速为环境因子,以Chla比增长率为评价指标,在室内进L9(34)的正交藻类培养实验,研究了环境因子对春季优势硅藻生长的影响.结果表明,在实验所设定的水平范围内,水体营养盐浓度总氮(TN)为3.5mg/L,总磷(TP)为0.3mg/L.水温20'C,光强为4700Lx以及流速为0.1 m/s时,最适宜藻类生长.4 因子对藻类生长影响大小依次为光强、流速、水温、营养盐浓度.流速在0.05m/s和0.1 m/s的情况下,藻类生长率明显高于静水.当 TN<1.5mg/L,TP<0.1mg/L时,增加TN,TP浓度可显著促进藻类生长;当TN,TP浓度分别达到3.5mg/L,0.3mg/L时,N,P浓度的增加对藻类生长影响甚微.%Three batches of water samples were collected from Xiangxi River between March to May 2010, and the L9(34)orthogonal experiments of algae growth were conducted in laboratory.Nutrient concentrations in water, water temperature,light intensity and water flow velocity were selected as environmental factors, and the growth rate of Chla was taken as evaluation index.The effects of environmental factors on the growth of preponderant diatoms in spring were studied.The optimal conditions for algal growth under the condition of the orthogonal experiments were 3.5mg/L for total nitrogen (TN), 0.3mg/L for total phosphorus (TP), 20℃ for water temperature, 4700lx for light intensity and 0.1m/s for flow velocity.The degree of impact of environmental factors on the algal growth was light intensity, velocity, water temperature and nutrient concentration in turn.The algae growth rates in flow water with velocity being 0.05m/s or 0.1 m/s was significantly higher than that in static water.The increase of TN and TP concentration could obviously promote the algae growth when TN＜1.5mg/L, TP＜0.1 mg/L;the effects of increasing TN and TP concentrations on algae growth was little when TN and TP concentrations respectively reached 3.5mg/L and 0.3mg/L.