滇池藻类动态变化规律及其与氮磷质量浓度的关系研究

Dynamic Changing Rule and the Relationship with Nitrogen and Phosphor Concentration of Planktonic Algae in Dianchi Lake

在2013年9月-2014年8月期间,每月监测滇池藻类及营养盐N和P的质量浓度,结果表明：外海N全年稳定,其值在1.70-2. 40mg/L;草海N 质量浓度呈双波峰变化,草海N 远高于外海.草海和外海P 质量 浓度在2013年10月-2014年2月均逐渐降低;草海和外海P在2014年4-7月持续增高,草海P远高于外海.外海蓝藻和绿藻呈互为消长,N质量浓度全年稳定, P质量浓度持续升高,而N/P下降（ TN：TP〈10） ,蓝 藻和绿藻迅速增加,但绿藻仍占有优势,说明高P 的水体中绿藻比蓝藻具有更强的利用优势.草海N和P变化剧烈且高于外海,N/P比率〉25时,蓝藻生物量极低,绿藻、硅藻占优,说明高N和 P质量浓度及N/P比率〉25 的草海中蓝藻不占优势,绿藻和硅藻占优.

The monitoring of algae and the concentration of nutrition N and P in Dianchi Lake has been made every month from Septem-ber, 2013-Autumn ,2014. The results show that the nitrogen content in Waihai of Dianchi lake was steady in every month with the range value of 1.70-2.40 mg/L, that of Caohai of Dianchi lake was double-peak pattern and nitrogen of Caohai was higher than that of Waihai. Phosphorous concentration in Caohai and Waihai gradually declined from October, 2013 to February, 2014, but rose from April to July, 2014, and phosphorous concentration in Caohai was far higher than that of Waihai. In Waihai, there was a trade-off relationship between cyanobacteria and cholorophyta and the nitrogen concentration was steady in all months; phosphor concentration was gradually rising, but the N/P ratio gradually declined （TN ：TP 〈 10） . The cyanobacteria and cholorophyta glowed rapidly, yet the cholorophyta was dominant, showing that cholorophyta owns stronger advantage for using than cyanobacteria in high phosphor content lake. In Caohai, the change of ni-trogen and phosphor concentration were more acutely higher than that of Waihai. When the N/P ratio was higher than 25, the biomass of cyanobacteria genus was very low and cholorophyta and diatom were dominant, showing that in Caohai with high N and P concentration and the N/P ratio higher than 25, cyanobacteria had no advantage but cholorophyta and diatom were more dominant algae.