scholarly journals Evaluation of landuse impacts on lakewater chemistry

1998 ◽  
Author(s):  
Keyword(s):  
Lakewater Chemistry

scholarly journals Norwegian lakes show widespread recovery from acidification; results from national surveys of lakewater chemistry 1986-1997

1998 ◽  
Vol 2 (4) ◽  
pp. 555-562 ◽  
Author(s):  
B. L. Skjelkvåle ◽  
R. F. Wright ◽  
A. Henriksen
Keyword(s):  
Base Cations ◽  
Chemical Recovery ◽  
N Leaching ◽  
National Scale ◽  
Western Norway ◽  
Acid Neutralising Capacity ◽  
Recovery From Acidification ◽  
Lakewater Chemistry ◽  
Southern Norway ◽  
Eastern Norway

Abstract. Surveys of 485 lakes in Norway conducted in 1986 and again in 1995 reveal widespread chemical recovery from acidification. Sulphate concentrations in lakes have decreased by 40% in acidified areas in southern Norway. This decrease has been compensated about 25% by decreases in concentrations of base cations and of 75% by increased Acid Neutralising Capacity (ANC). The increased ANC in turn reflects lower concentrations of acidic cations Aluminum (ALn+) and Hydrogen (H+). A sub-set of 78 of the 485 lakes sampled yearly between 1986 and 1997 shows that, at first most of the decrease in non-marine sulphate (SO4*) was compensated by a decrease in base cations, such that ANC remained unchanged. Then as SO4* continued to decrease, the concentrations of non- marine calcium and magnesium ((Ca+Mg)*) levelled out. Consequently, ANC increased, and H+ and Aln+ started to decrease. In eastern Norway, this shift occurred in 1989–90, and came slightly later in southern and western Norway. Similar shifts in trends in about 1991–92 can also be seen in the non-acidified areas in central and northern Norway. This shift in trends is not as pronounced in western Norway, perhaps because of the confounding influence of sea-salt episodes on water chemistry. This is the first documented national-scale recovery from acidification due to reduced acid deposition. Future climate warming and potentially increased N-leaching can counteract the positive trends in recovery from acidification.

Effects of multiple stressors on lakes in south-central Ontario: 15 years of change in lakewater chemistry and sedimentary diatom assemblages

2012 ◽  
Vol 75 (3) ◽  
pp. 349-360 ◽  
Author(s):  
Kristopher R. Hadley ◽  
Andrew M. Paterson ◽  
Roland I. Hall ◽  
John P. Smol
Keyword(s):  
Multiple Stressors ◽  
Diatom Assemblages ◽  
South Central ◽  
Lakewater Chemistry

Quantification of changes in lakewater chemistry in response to acidic deposition

Nature ◽  
1990 ◽  
Vol 345 (6270) ◽  
pp. 54-58 ◽  
Author(s):  
T. J. Sullivan ◽  
D. F. Charles ◽  
J. P. Smol ◽  
B. F. Cumming ◽  
A. R. Selle ◽  
...  
Keyword(s):  
Acidic Deposition ◽  
Lakewater Chemistry

Calcium declines in northeastern Ontario lakes

2001 ◽  
Vol 58 (10) ◽  
pp. 2011-2020 ◽  
Author(s):  
W Keller ◽  
S S Dixit ◽  
J Heneberry
Keyword(s):  
Water Quality ◽  
20Th Century ◽  
Acid Deposition ◽  
Forest Harvesting ◽  
Climatic Changes ◽  
Quality Improvements ◽  
Sulphur Deposition ◽  
Lakewater Chemistry

Thousands of lakes in northeastern Ontario, Canada, have been acidified by sulphur deposition associated with emissions from the Sudbury area metal smelters. However, water quality improvements including increased pH and reduced sulphate concentrations have followed large reductions in Sudbury emissions that were implemented, beginning in the 1970s. Substantial decreases in Ca concentrations accompanied these other changes in lakewater chemistry. Monitoring of 38 lakes 20–128 km from Sudbury showed declines in Ca concentrations, averaging 2.7 µeq·L–1·year–1, over the period 1981–1999. Declines were particularly apparent during the 1990s, averaging 3.8 µeq·L–1·year–1. Paleolimnological reconstructions of the long-term Ca patterns in six lakes suggest that general lakewater Ca declines occurred through much of the 20th century. Comparison of recent measured Ca concentrations in 16 lakes with diatom-inferred pre-industrial Ca concentrations indicates that overall decreases in Ca have been large, averaging 74.6 µeq·L–1 or 46%. Long-term Ca patterns may reflect a combination of factors including climatic changes, forest harvesting activities, and leaching by acid deposition, the effects of which we can not separate. Calcium declines have biological implications that will need to be considered in the development of appropriate targets as these lakes continue to recover from acidification.

VARIATION IN ADIRONDACK, NEW YORK, LAKEWATER CHEMISTRY AS FUNCTION OF SURFACE AREA

1990 ◽  
Vol 26 (1) ◽  
pp. 167-176 ◽  
Author(s):  
T J. Sullivan ◽  
D. L. Kugler ◽  
M. J. Small ◽  
C. B. Johnson ◽  
D. H. Landers ◽  
...  
Keyword(s):  
New York ◽  
Surface Area ◽  
Lakewater Chemistry

Application of a regionalized knowledge-based model for classifying the impacts of nitrogen, sulfur, and organic acids on lakewater chemistry

2005 ◽  
Vol 18 (1) ◽  
pp. 55-68 ◽  
Author(s):  
T.J. Sullivan ◽  
M.C. Saunders ◽  
K.A. Tonnessen ◽  
B.L. Nash ◽  
B.J. Miller
Keyword(s):  
Organic Acids ◽  
Knowledge Based ◽  
Lakewater Chemistry

Atmospheric wet sulphate deposition and lakewater chemistry

Nature ◽  
1988 ◽  
Vol 331 (6157) ◽  
pp. 607-609 ◽  
Author(s):  
T. J. Sullivan ◽  
J. M. Eilers ◽  
M. R. Church ◽  
D. J. Blick ◽  
K. N. Eshleman ◽  
...  
Keyword(s):  
Sulphate Deposition ◽  
Lakewater Chemistry
Sign in / Sign up

Export Citation Format

Share Document