Metal to phosphorus stoichiometries for freshwater phytoplankton in three remote lakes

PeerJ

article

Aine M. Gormley-Gallagher¹  Richard W. Douglas¹  Brian Rippey¹ 

[1] School of Geography & Environmental Sciences, University of Ulster

关键词: Metal;    Phytoplankton;    Phosphorus;    Freshwater;    Lakes;    Stoichiometries;    Scotland;   

DOI  :  10.7717/peerj.2749

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Simultaneous measurements of changes in phytoplankton biomass and the metal and phosphorus (P) content of cells have been captured to attest to metal to P stoichiometries for freshwater phytoplankton. Three Scottish lakes that had received high, medium or low metal contamination from the atmosphere were selected for study. Phytoplankton cells were collected and Inductively Coupled Plasma-Mass Spectrometry was used to measure their lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu), zinc (Zn), nickel (Ni), chromium (Cr), manganese (Mn), cobalt (Co) and P content. Increased phytoplankton growth in the lakes resulted in significant algae growth dilution of the mass-specific Pb, Cd, Hg, Cu, Ni and Cr in the phytoplankton. Changes in the phytoplankton cell count and their Hg, Pb, Cd, Cu, Mn, Co, Ni and Cr concentrations showed the process of algae bloom dilution to be subject to exponential decay, which accelerated in the order of Mn < Cu < Ni < Pb and Cd < Cr and Hg < Co. This indicated a metabolic and detoxification mechanism was involved in the active selection of metals. For the first time simultaneous measurements of metals and P stoichiometry in freshwater phytoplankton are reported. The mean metal to P stoichiometry generated was (C106P1N16)1000Pb0.019Hg0.00004Cu0.013Cd0.005Cr0.2Co0.0008Mn0.2Ni0.012 based on field measurements and the Redfield average C, N and P stoichiometry of (CH2O)106(NH3)16H3PO4.

【 授权许可】

CC BY