Variability in diatom and chrysophyte assemblages and inferred pH: paleolimnological studies of Big Moose Lake, New York, USA

1991 ◽  
Vol 5 (3) ◽  
Author(s):  
DonaldF. Charles ◽  
SushilS. Dixit ◽  
BrianF. Cumming ◽  
JohnP. Smol
Keyword(s):  
New York ◽  
Inferred Ph

Assessing pH changes since pre-industrial times in 51 low-alkalinity lakes in Nova Scotia, Canada

2007 ◽  
Vol 64 (8) ◽  
pp. 1043-1054 ◽  
Author(s):  
Brian K Ginn ◽  
Brian F Cumming ◽  
John P Smol
Keyword(s):  
New York ◽  
Nova Scotia ◽  
New England ◽  
National Park ◽  
Ph Changes ◽  
Ph Values ◽  
Sulphate Deposition ◽  
Kejimkujik National Park ◽  
Inferred Ph ◽  
The 19Th Century

Diatom-based paleolimnological techniques were used to reconstruct lake acidification trends in 51 low-alkalinity Nova Scotia lakes that spanned gradients of dissolved organic carbon (DOC) concentrations and sulphate deposition. Pre-industrial, diatom-inferred pH values of these lakes were <6.8, with 31 lakes having pre-industrial pH < 6.0 and two lakes having pH < 5.5. Lakes in Kejimkujik National Park documented the greatest pH decline (–0.4 pH unit (±0.2)) since the 19th century, whereas those in northern parts of the province (e.g., Cape Breton Highlands National Park) experienced little or no acidification, with a net mean pH decline = –0.1 pH unit (±0.2). While the sulphate deposition and diatom-inferred pH changes have not been as great as those observed in other acidified areas of northeastern North America (e.g., Adirondack region of New York or New England), Nova Scotia lakes have experienced biological changes toward more acidophilous diatom assemblages, especially in lakes with low pre-industrial pH values (currently with high DOC concentrations) located in Kejimkujik National Park, which receives the highest loading of sulphate deposition in Nova Scotia. However, the generally low pre-industrial pH values inferred for most of the study lakes suggest that many of these lakes were somewhat naturally acidic, but acidified further as a result of atmospheric deposition.

Treating Abused Adolescents. By E. Gil. Guilford Press, New York, 1996. pp. 228. £32.00 (hb).

1998 ◽  
Vol 39 (2) ◽  
pp. 279-284
Author(s):  
Gerrilyn Smith
Keyword(s):  
New York
Sign in / Sign up

Export Citation Format

Share Document