Physiological characteristics of diatom Nitzschia palea for ecological engineering countermeasure method of water blooms

Abstract

 This study is to investigate the effect of nutrients, temperature, and pH on the growth characteristics of diatom Nitzschia palea which may be the competitors of bloom forming cyanobacteria. This may be the basis for an ecological engineering method using by N. palea. The maximum specific growth rate (𝜇_𝑚𝑎𝑥) and the half-saturation constant of nitrogen (𝐾_𝑁) for N. palea were estimated as 0.52 day^-1 and 0.12 mgN L^-1, respectively. 𝜇_𝑚𝑎𝑥 and 𝐾_𝑃 of phosphorus for N. palea were estimated as 0.62 day^-1 and 0.035 mgP L^-1, respectively. 𝜇_𝑚𝑎𝑥 and 𝐾_𝑆𝑖 of silicon for N. palea were estimated as 0.68 day^-1 and 0.48 mgSi L^-1, respectively. The temperature for optimal growth was 15~25 ℃. Moreover N. palea maintained high growth rate at 30 ℃. The optimal pH for the growth of N. palea was 7.0-9.0. Therefore N. palea can be used as competitors for bloom forming cyanobacteria in the temperature during summer and an alkaline condition, in which the bloom usually occurs.