Abstract
Periphyton growth limitation experiments were conducted in five glacier streams during the main ice melt period in late summer using nutrient diffusing substrata (NDS) that contained nitrate and/or phosphate. Periphyton net growth was determined as chlorophyll a accrual after an exposure time of 4 weeks. In addition, primary water chemistry and physical parameters of the study streams were measured. These chemical and physical parameters characterised the sites as kryal (glacial) systems. Neither nutrient limitation nor a significant correlation between water chemistry and physical data and chlorophyll a values were apparent. A comparison between current velocity and ln-transformed chlorophyll a values revealed a typical optimum curve with highest periphyton accrual at 0.5 m s–1 on NDS. During the summer ablation period, the net growth of periphyton in these glacial streams appeared to be controlled primarily by current velocity.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have