Paleoecological analysis of lake-acidification trends in Nrth America and Europe using diatoms and chrysophytes. Draft report (Final)

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:5192132

Charles, D F; Battarbee, R W; Renberg, I; van Dam, H; Smol, J P

Analysis of sediment diatom and chrysophyte assemblages is the best technique currently available for inferring past lakewater pH trends; use of this approach is increasing rapidly. Sediment-core-inferred pH data exist for at least 100 lakes in both North America and Europe. The number will approximately double within the next two years. The pH-inference equations are based on at least 15 calibration data sets for North America and 10 for Europe, involving totals of at least 500 and 300 lakes, respectively. Paleoecological studies indicate that recent acidification has been caused by acidic deposition. In most cases, the primary cause of recent acidification trends (post-1850) is atmospheric deposition of acidic material, as opposed to land-use changes or natural processes, though these may be contributing factors. Acid loading has decreased in some regions since 1970; some lakes have become less acidic in response, but others continue to lose buffering capacity and are becoming more acidic. Many currently acidic lakes were naturally acidic (pH < 5.5) prior to the onset of anthropogenic acidification. These lakes are typically small (< 10 ha), located at moderately high elevations, have thin or peaty soils, or are located in outwash deposits. Many of these have acidified further recently.

• Research Organization: NSI Technology Services Corp., Corvallis, OR (USA)
• OSTI ID: 5192132
• Report Number(s): PB-90-113762/XAB
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540120 -- Environment
Atmospheric-- Chemicals Monitoring &amp; Transport-- (1990-)
540320* -- Environment
Aquatic-- Chemicals Monitoring &amp; Transport-- (1990-)
560300 -- Chemicals Metabolism &amp; Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACID NEUTRALIZING CAPACITY
ACID RAIN
ACIDIFICATION
AIR POLLUTION
AIR-WATER INTERACTIONS
ALGAE
ATMOSPHERIC PRECIPITATIONS
BIOLOGICAL INDICATORS
CHEMISTRY
CHROMOPHYCOTA
DEPOSITION
DIATOMS
DOCUMENT TYPES
EUROPE
LAKES
LIMNOLOGY
NAPAP
NORTH AMERICA
PH VALUE
PLANTS
POLLUTION
PROGRESS REPORT
RAIN
SEDIMENTS
SURFACE WATERS
WATER CHEMISTRY
WATER POLLUTION
WATERSHEDS