Freshwater stream ecosystems of James Ross Island, Antarctica

• Published in: Antarctic Science
• Main Authors: Hawes, Ian, Brazier, Paul
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1991
• Subjects: Antarctic; Ross Island; Antarc*; Antarctic Science; Antarctica; James Ross Island
• Online Access: http://dx.doi.org/10.1017/s0954102091000329; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102091000329

The freshwater streams of James Ross Island share many of the features common to other Antarctic streams. There is a diel variation in temperature and discharge, which follows the daily insolation cycle; catchments are barren; stream vegetation is predominantly algal, comprising mat-forming cyanobacteria and filamentous chlorophytes; and physical factors, particularly turbidity and bed stability are important in determining biomass and composition of algal assemblages. Nutrient concentrations vary from stream to stream and over a diel cycle, with minimum dissolved N in late afternoon. Biomass attained and photosynthetic and respiratory rates are also comparable to those recorded in other Antarctic streams, with low productivity/biomass ratios in perennial assemblages.