From Greenland to green lakes: Cultural eutrophication and the loss of benthic pathways in lakes

• Main Authors: Vadeboncoeur, Y., Jeppesen, E., Zanden, M. J. V., Schierup, H.-H., Christoffersen, K., Lodge, D. M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2003
• Subjects: Greenland
• Online Access: https://curis.ku.dk/portal/da/publications/from-greenland-to-green-lakes-cultural-eutrophication-and-the-loss-of-benthic-pathways-in-lakes(d478f330-74c4-11db-bee9-02004c4f4f50).html

benthic algae, production, eutrophicaiton, stable isotope Benthic community responses to lake eutrophication are poorly understood relative to pelagic responses. We compared phytoplankton and periphyton productivity along a eutrophication gradient in Greenland, U.S., and Danish lakes. Phytoplankton productivity increased along the phosphorus gradient (total phosphorus [TP] 5 2–430 mg m23), but whole-lake benthic algal productivity decreased, substantially depressing increases in primary productivity at the whole-lake scale. In shallow, oligotrophic Greenland lakes, periphyton was responsible for 80–98% of primary production, whereas in Danish lakes with TP . 100 mg m23, phytoplankton were responsible for nearly 100% of primary production. Benthic contributions ranged from 5 to 80% depending on morphometry and littoral habitat composition in lakes with intermediate phosphorus concentrations. Thus, eutrophication was characterized by a switch from benthic to pelagic dominance of primary productivity. Carbon stable isotope analysis showed that the redistribution of primary production entailed a similar shift from periphyton to phytoplankton in the diets of zoobenthos. Benthic and pelagic habitats were energetically linked through food web interactions, but eutrophication eroded the benthic primary production pathway.