Aquatic Microbial Ecology
Environmental factors such as temp erature, irradiance, and nitrogen (N) supply affect the growth of Prorocentrum donghaiense, but the interactive effects of these physical factors and the effects of atmospheric CO2 (pCO2) on growth and N uptake have not been examined. We compared growth kinetics of P. donghaiense grown on 4 different N substrates (nitrate [NO3 -], ammonium [NH4 +], urea, and glutamic acid [glu]) with respect to temperature, irradiance, and pCO2. Temperature (15 to 30°C) had a positive effect on growth (max. growth rates: 0.17 to 0.65 d-1; optimal temperature: 25 to 30°C); maximum specific growth rates (μmax) declined when cultures were grown at 30°C. P. donghaiense grew well on all 4 N sources, under irradiances ranging from 10 to 180 μmol quanta m-2 s-1. μmax (2.0 ± 0.1 d-1) was observed in cultures growing with NH4+ as the sole N source in the highest irradiance treatment (180 μmol quanta m-2 s-1). These rates were significantly higher than those measured in cultures grown on NO3 -, urea, and glu (all ∼1.4 d-1). Half-saturation constants (Ks) ranged from 66.5 ± 4.6 to 99.4 ± 6.7 μmol quanta m-2 s-1 for cultures grown with glu or NH4+, respectively, as the sole source of N. Both growth and N uptake rates were higher in cultures grown under elevated pCO2. Our results suggest that P. donghaiense exhibits flexible adaptation for N utilization under broad environmental conditions (temperature, irradiance, pCO2), which may play an important role in the formation and duration of P. donghaiense blooms.
Original Publication Citation
Hu, Z., Mulholland, M. R., Xu, N., & Duan, S. (2016). Effects of temperature, irradiance and pCO2 on the growth and nitrogen utilization of Prorocentrum donghaiense. Aquatic Microbial Ecology, 77(3), 155-166. doi:10.3354/ame01793
Hu, Zhangxi; Mulholland, Margaret R.; Xu, Ning; and Duan, Shunshan, "Effects of Temperature, Irradiance and pCO2 on the Growth and Nitrogen Utilization of Prorocentrum Donghaiense" (2016). OEAS Faculty Publications. 243.
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