thumbnail

Cumulative effects of nutrients and pH on the plankton of two mountain lakes

Canadian Journal of Fisheries and Aquatic Sciences

By:
, , , and ORCID iD
https://doi.org/10.1139/f04-053

Links

Abstract

We conducted enclosure experiments to examine the cumulative effects of nutrient enrichment and acidification on the plankton of two mountain lakes with differing nutrient conditions. The low-nitrate lake responded to N, N plus acid, and N plus acid plus P additions, showing four- to seven-fold increases in chlorophyll a, increased photosynthetic rate, compositional shifts toward large chlorophytes, and decreased zooplankton biomass. The high-nitrate lake responded minimally to either N or P alone but responded strongly to combined additions of N plus acid plus P, showing eightfold increases in chlorophyll a, increased cell density and photosynthetic rates, and compositional shifts toward chlorophytes and the dinoflagellate Gymnodinium. In both study lakes, changes in chlorophyll a were linked to addition of limiting nutrients regardless of pH, whereas shifts in phytoplankton species composition were apparently affected by both nutrient conditions and acidity. The most striking changes in species composition and biomass occurred in combined N plus acid plus P treatments, indicating that continued nutrient enrichment may interact with acidification to produce marked changes in the plankton of mountain lakes.

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Cumulative effects of nutrients and pH on the plankton of two mountain lakes
Series title:
Canadian Journal of Fisheries and Aquatic Sciences
DOI:
10.1139/f04-053
Volume:
61
Issue:
7
Year Published:
2004
Language:
English
Publisher:
NRC Research Press
Contributing office(s):
Fort Collins Science Center
Description:
13 p.
First page:
1153
Last page:
1165