Freshwater benthic algal population and community changes due to acidity and aluminum-acid mixtures in artificial streams
- Johnson State Coll., VT (United States)
Communities of freshwater benthic algae were exposed to water acidified daily to pH 4.8 along and in mixtures with 50, 100, or 500 [mu]g L[sup [minus]1] Al. Daily acidification to nominal pH 4.8 in acidified treatments exposed algae to a range of pHs that led to a variety of Al species of different toxicity. Calcium concentrations in stream were higher in acidified and Al treatments on day 1, and dissolved Al in stream water was higher in the highest Al treatment on days 1, 7, and 28; otherwise acid and Al treatments did not significantly alter Al and Ca in the exposure water. Calcium bioaccumulation by periphyton was lower in acidified and Al treatments on all sampling days. Concentrations of Mg in water and periphyton did not differ between treatments. The artificial stream system generated alkalinity to buffer acidified water; the amount of generated alkalinity returned to approximately the same levels for the first week, but the amount of alkalinity generated during the second week appeared to decline, and acid-only and acid-Al mixtures diverged in their ability to generate alkalinity during the third and fourth weeks. Aluminum in acidified water inhibited abundance of diatoms and green and blue-green algae more than the effects of acid stress alone. The green filamentous alga Mougeotia showed a slight increase in abundance in the acid-only treatment. The middle-Al treatment generated more alkalinity and had higher abundance of some algal taxa on days 14 and 28, even though measured Al concentrations in water and periphyton fell between low- and high-Al-treatment levels. Community-level tests, combining a taxonomic analysis of algal population abundance with chemical analysis of water and bioaccumulation, provide valuable insight to assess anthropogenic stress.
- OSTI ID:
- 5137046
- Journal Information:
- Environmental Toxicology and Chemistry; (United States), Vol. 13:3; ISSN 0730-7268
- Country of Publication:
- United States
- Language:
- English
Similar Records
Metal toxicity inferred from algal population density, heterotrophic substrate use, and fatty acid profile in a small stream
Applying the light: nutrient hypothesis to stream periphyton
Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALGAE
SENSITIVITY
ALUMINIUM
BIOLOGICAL EFFECTS
ENVIRONMENTAL EFFECTS
STREAMS
ACIDIFICATION
GENETIC VARIABILITY
WATER POLLUTION
BIOLOGICAL VARIABILITY
ELEMENTS
METALS
PLANTS
POLLUTION
SURFACE WATERS
540320* - Environment
Aquatic- Chemicals Monitoring & Transport- (1990-)
560300 - Chemicals Metabolism & Toxicology