Abstract:
Globally, cyanobacteria frequently cause blooms that outcompete other species in the waterbody, affecting the diversity, decreasing water exchange rates, and promoting eutrophication that leads to excessive algal growth. Here, Dolichospermum circinale (akinetes) and Microcystic aeruginosa (resting cells), were isolated from the sediment in the Uiam Dam in the North Han River and near Ugok Bridge in the Nakdong River, respectively. The morphology, germination process and rates, and growth was evaluated in different environmental conditions. D. cercinalis germination began on day two of culturing, with maximum cell growth observed on day ten. In contrast, M. aeruginosa exhibited daily increase in cell density and colony size, with notable density increase on day six. Next, different environmental conditions were assessed. Akinetes exhibited high germination rates at low light intensity (5-30 µmol/m2/s), whereas resting cells exhibited high growth rates at high light intensity (50-100 µmol/m2/s). Furthermore, both cell types exhibited optimum germination and growth in media containing N and P at 20-30° at a pH of 7-9. Our study reveals the optimum conditions for the germination and growth of cyanobacterial akinetes and resting cells isolated from river sediment, respectively, and will assist in predicting cyanobacterial blooms for appropriate management.
摘要:
全球范围内,蓝细菌经常引起水华,胜过水体中的其他物种,影响多样性,降低水汇率,并促进导致藻类过度生长的富营养化。这里,圆形Dolichospermumcircinale(akinetes)和铜绿微囊藻(静息细胞),从北汉江的Uiam大坝和Nakdong河的Ugok桥附近的沉积物中分离出来,分别。形态学,发芽过程和速率,在不同的环境条件下进行生长评价。D.cercinalis发芽开始培养的第二天,在第10天观察到最大细胞生长。相比之下,铜绿M.表现出细胞密度和菌落大小的每日增加,第六天密度显著增加。接下来,评估了不同的环境条件。Akinetes在低光照强度(5-30µmol/m2/s)下表现出高发芽率,而静息细胞在高光照强度(50-100µmol/m2/s)下表现出高生长速率。此外,两种细胞类型在pH为7-9的20-30°含N和P的培养基中表现出最佳的萌发和生长。我们的研究揭示了从河流沉积物中分离出的蓝藻和静止细胞的萌发和生长的最佳条件,分别,并将有助于预测蓝藻水华以进行适当的管理。