Responses of freshwater plants and invertebrates to acidification

Conference · Tue Jan 01 00:00:00 EST 1980

OSTI ID:7033261

Hendrey, G R; Yan, N D; Baumgartner, K J

Acidic, oligotrophic, clear waters often have strong similarities among their biota. In the phytoplankton, Dinophyceae, and to a lesser extent Chrysophyceae tend to dominate. Production of 25 Canadian Shield lakes (pH 6.1-7.1) ranged from 25 to 240 mg C m/sup -2/ d/sup -1/. Both biomass and production appear to be controlled by the supply and bio-availability of phosphorus rather than pH per se. We found little evidence of possible C limitation in acidified lakes. There does not appear to be a direct relationship between (H/sup +/) and biomass density in lakes, as illustrated by whole-lake manipulations of (H/sup +/) and total phosphorus (TP). These studies, however, do not examine effects of acidification on the whole lake-watershed system. It is suggested that watershed acidification processes such as leaching of Al may reduce TP loading to lakes. Zooplankton community biomass appears to be reduced at low pH and small-bodied forms may dominate. Among the zoobenthos, biomass does appear to be reduced in some lakes but not others. Various studies found shredders; collectors and scrapers to be reduced more than raptorial species. We hypothesize that removal of fish predation on benthos allows a relative increase in the invertebrate predators, reduction of herbivores (chironomids are relatively abundant) and the subsequent increase in benthic algae observed in many waters.

• Research Organization: Brookhaven National Lab., Upton, NY (USA); Ontario Ministry of the Environment, Toronto (Canada); Dartmouth Coll., Hanover, NH (USA). Dept. of Biological Sciences
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 7033261
• Report Number(s): BNL-28534; CONF-8009120-1
• Resource Relation: Conference: EPA/OECD international symposium for inland waters and lake restoration, Portland, ME, USA, 8 Sep 1980
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ACIDIFICATION
ENVIRONMENTAL EFFECTS
PHYTOPLANKTON
BIOMASS
PRODUCTIVITY
ZOOPLANKTON
POPULATION DYNAMICS
BENTHOS
LAKES
NUTRIENTS
PH VALUE
AQUATIC ORGANISMS
ENERGY SOURCES
PLANKTON
RENEWABLE ENERGY SOURCES
SURFACE WATERS
520200* - Environment
Aquatic- Chemicals Monitoring & Transport- (-1989)