for photosynthesis
Photosynthesis vs. irradiance relationships were determined for phytoplankton communities from seven lakes in the Canadian high Arctic, including ultraoligotrophic Char Lake, nutrient-enriched Meretta Lake, and two meromictic lakes. The derived photosynthetic parameters were low for all samples, wit...
| Main Authors: | , , |
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| Format: | Text |
| Language: | English |
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.419.3098 http://www.aslo.org/lo/toc/vol_44/issue_3/0597.pdf |
| Summary: | Photosynthesis vs. irradiance relationships were determined for phytoplankton communities from seven lakes in the Canadian high Arctic, including ultraoligotrophic Char Lake, nutrient-enriched Meretta Lake, and two meromictic lakes. The derived photosynthetic parameters were low for all samples, with a mean (�SD) light-saturated photosynthetic rate (P) of 0.46 (�0.28) g C g�1 chlorophyll a (Chl a) h�1 and a mean �B B (light-limitation parameter) m of 1.23 (�0.56) g C g�1 Chl a m2 mol�1. The saturation irradiance (Ek) ranged from 50 to 196 �mol quanta m�2 s�1 and was positively correlated with mean irradiance for the water column. Quantum yields for photosynthesis in the Arctic lake phytoplankton were also low (mostly �10 mmol C mol�1 quanta). An intersystem comparison of �B B and Pm values with literature data for algae from other cold environments showed that the photosynthetic parameters for phytoplankton in Arctic and Antarctic lakes are three- to sixfold lower than for marine algae, ice algae, and cultures over the same low-temperature range. This may be the result of more severe nutrient stress in high-latitude lakes relative to polar marine environments and to the persistence of nonactive pigments in cold |
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