氨氮浓度对苦草上附植藻类定植的影响

Response of Attached Algae Colonization of Vallisneria natans to Ammonia Nitrogen Supply

为了认识水体富营养化过程中附植藻类群落定植演替规律,利用显微计数法,通过室内静态模拟实验,研究了水体中不同氨氮浓度对太湖常见沉水植物苦草上附植藻类的影响。结果表明:采集的样品在以硅藻门中脆杆藻属、直链藻属、桥弯藻属、舟行藻属以及蓝藻门的色球藻属为优势种的样品在放置到不同浓度氨氮的实验组后,最后群落演变成为在低浓度氨氮营养盐下以舟行藻和脆杆藻为优势属,中高浓度的氨氮营养盐下以绿藻门的毛枝藻和硅藻门的小环藻和舟行藻为优势属的附植藻类群落结构;生物量在低浓度范围内与氨氮营养盐呈正相关。表明氨氮营养盐对附植藻类群落结构影响非常明显。

To recognize community succession rules of attached algae in the eutrophic water body, ruacroscope counting method was used to study the responses of attached algae on Taihu Lake submerged macrophyte Vallisneria natans to ammonia nitrogen （AN）supply by static incubation test. Results showed that Frailaria of Bacillariophyta, Melosira, Cymbella, Navicula, Chroococcus of Cyanophyta were dominant species at the collected sample, then they were evolved into Navicula, Frailaria as dominant species at low AN level and Stigeoclonium of Chlorophyta, Cyclotella, Navicula of Bacillariophyta at high AN level when laid into glass cylinder of tested group of different AN levels. The bioruass was positively correlated to low AN level, indicating AN level was important to attached algae.