Nutrient kinetics of dominant species of phytoplankton in the artificial lakes formed from land subsidence by mining activities in the Huainan coalmine subsidence areas

Abstract

在淮南潘谢矿区选取3个营养盐结构差异较大的塌陷湖泊，于2014-2015年4个季度分别对浮游植物群落结构组成进行调查，选取3个湖泊中的优势种（属）具尾蓝隐藻（Chroomonas caudata）、链形小环藻（Cyclotella catenata）和伪鱼腥藻（Pseudanabaena sp.）作为研究对象，设置不同的氮（N）、磷（P）浓度梯度进行营养动力学培养实验，并结合Monod方程，获得3个藻种在不同营养盐限制下的营养动力学参数.N限制下具尾蓝隐藻、小环藻和伪鱼腥藻的最大生长速率（μ_max）和半饱和常数（Ks）分别为：0.66 d^-1、1.66 mg/L；0.37 d^-1、1.06 mg/L；0.71 d^-1、2.26 mg/L；P限制下它们的μ_max和Ks则分别为：0.51 d^-1、0.023 mg/L；0.31 d^-1、0.035 mg/L；0.90 d^-1、0.015 mg/L.综上所述，在N充足时，伪鱼腥藻能够在竞争中形成优势，同时在P限制情况下易成为优势种，从营养动力学的角度揭示了其在塌陷湖泊中占据优势的营养盐动力学机制.研究结果可以为沉陷区水域开发利用和营养盐管理提供科学依据.;Three lakes in the Huainan Panxie coalmine areas, with different nutrient ratio, were investigated for their phytoplankton communities in four seasons from 2014 to 2015. Three dominant species (genera) of phytoplankton, including Chroomonas caudata, Cyclotella catenata and Pseudanabaena sp., were selected to obtain their nutrient kinetics by a number of incubation experiments with limitation for individual nitrogen (N) and phosphorus (P). Under N limitation conditions, the maximum specific growth and half-saturated constant for the three species of Chroomonas caudate, Cyclotella catenata and Pseudanabaena sp. were 0.66 d^-1 and 1.66 mg/L, 0.37 d^-1 and 1.06 mg/L, 0.71 d^-1 and 2.26 mg/L, respectively; with respect of P limitation conditions, they were 0.51 d^-1 and 0.023 mg/L, 0.31 d^-1 and 0.035 mg/L, 0.90 d^-1 and 0.015 mg/L, respectively. Especially, the Pseudanabaena sp. takes dominant role due to its nutrient competition ability under P limitation in this type of lakes, where N is sufficient for its growth. This research has important implication on local nutrient management of water resources in the coal mine areas.