曝气扰动促进高营养的饲料腐烂液中绿藻生长

Aeration disturbance promotes the growth of green algae at high nutrients level from fish feed decomposition

摘要:

为了研究饲料腐烂形成的高氮、磷营养盐条件下浮游植物的自发生长,夏季在玻璃温室进行了以鱼类配合饲料腐烂液为营养源的实验。实验设1个对照组和1个处理组,对照组中不曝气,处理组在12 d起进行持续曝气扰动。结果表明,曝气显著提高了水中溶解氧、pH、氧化还原电位、叶绿素a和浮游植物总生物量。对照组叶绿素a较低,在第10~17 天形成峰值,处理组叶绿素a在第27 天达到最高值(1 169.57±1 133.01) μg/L,藻生物量在第25 天达到最高值(279.07±339.83) mg/L。第21~31 天,处理组中绿藻门的栅藻属(Scenedesmus spp.)为优势种,而对照组中绿藻门的衣藻属(Chlamydomonas spp.) 和绿球藻(Chroococcus sp.)为优势种。在曝气条件下,以鱼类配合饲料腐烂降解形成总氮、总磷质量浓度分别为3.8~22.1、2.1~16.9 mg/L的高营养水平,出现绿藻门栅藻属优势。

Abstract:

In order to study what kinds of phytoplankton can grow spontaneously at high nitrogen and phosphorus levels formed from compound fishing feed decomposition, an experiment was carried out in a greenhouse during summer. The experiment included a control group with no aeration and a treatment group aerated continuously from day 12. The results revealed that the aeration significantly improved dissolved oxygen, pH, oxidation reduction potential values, chlorophyll a, and total algal biomass in the water. Chlorophyll a in the control was low but formed a peak from days 10 to 17, while that in the treatment reached its highest value of (1 169.57 ± 1 133.01) μg/L on day 27, and the highest algal biomass was (279.07±339.83) mg/L on day 25. Green algae particularly Scenedesmus spp. dominated in the treatment, and green algae particularly Chlamydomonas spp. and Chroococcus sp. dominated in the control, from days 21 to 31. Therefore, green algae dominated under aeration at high nutrient level of 3.8-22.1 mg/L total nitrogen and 2.1-16.9 mg/L total phosphorus, which was derived from decomposing compound fish feed.