Aquatic mollusks in North Dakota during the last 12000 years

1976 ◽  
Vol 54 (10) ◽  
pp. 1688-1693 ◽  
Author(s):  
A. M. Cvancara
Keyword(s):  
Surface Water ◽  
Water Chemistry ◽  
North Dakota ◽  
Surface Waters ◽  
Surface Water Chemistry ◽  
Changing Climate ◽  
Dissolved Salts

Aquatic mollusks occurred in North Dakota during the last 12 000 years as follows: 12 000–10 000 years ago, 19 species (dated material from 3 sites); 10 000–8000 years ago, 22 species (dated material from 5 sites); 8000–4000 years ago, 11 species (material of inferred age from 2 sites); 4000 years ago to present, 36 species (dated material from 1 site and material of inferred age from 23 sites); and present day, 44 species (material from about 300 stations). The gastropods Valvata sincera (Say), Fossaria decampi (Streng), and Helisoma campanulatum (Say) have not been found in sediments younger than about 9600 years. They may have become regionally extinct about 9000 years ago because of a warmer, drier climate and a corresponding increase of dissolved salts in surface waters. Of two hydrobiid gastropods, Amnicola limosa (Say) has not been found in sediments younger than about 9000 years and has been found at relatively few localities today. Cincinnatia cincinnatiensis (Anthony) has not been found in sediments older than about 2500 years and has been found at many localities today. The occurrence of these two species with time may also be the result of changing climate and surface-water chemistry.

scholarly journals Multi-year impacts of permafrost disturbance and thermal perturbation on High Arctic stream chemistry

2017 ◽  
Vol 3 (2) ◽  
pp. 254-276 ◽  
Author(s):  
Daniel Lamhonwah ◽  
M. J. Lafrenière ◽  
S. F. Lamoureux ◽  
B. B. Wolfe
Keyword(s):  
Surface Water ◽  
Water Chemistry ◽  
Surface Waters ◽  
High Arctic ◽  
Thermal Perturbation ◽  
Surface Water Chemistry ◽  
Near Surface ◽  
Ion Concentrations ◽  
Soluble Ions ◽  
Soil Temperatures

Permafrost disturbances (such as active layer detachment (ALD) slides) and thermal perturbation (deep ground thaw from high soil temperatures) alter Arctic surface water chemistry. However, the potential multi-year impacts on water chemistry and the ultimate recovery time are not well understood. This study evaluates the impacts on surface waters and recovery following disturbance of a High Arctic catchment in 2007 from ALDs. We measured ion concentrations and stable isotopes in surface waters collected between 2006 and 2014 from paired catchments — one disturbed and the other not. The years 2007 and 2012 were exceptionally warm and represent unusual thermal perturbation for both catchments. Results indicate that the exposure and mobilization of soluble ions in near surface soil is a key control over dissolved ion concentrations and composition following ALDs. Runoff in the disturbed catchment shows increased total dissolved solute (TDS) concentrations and seasonal TDS fluxes and changes to the relative composition of individual ions in surface water. These impacts persisted for the 7 year study duration after disturbance and are consistent with the thawing of the solute-rich transient layer and upper permafrost. Thermal perturbation increased TDS concentrations and seasonal fluxes in runoff for up to 2 years, as ions released from ground thaw appear to be available for flushing in subsequent summers.

scholarly journals Tailings Dust Characterization and Impacts on Surface Water Chemistry

2021 ◽  
Author(s):  
Amy Cleaver ◽  
Heather Jamieson ◽  
Carrie Rickwood ◽  
Philippa Huntsman
Keyword(s):  
Surface Water ◽  
Water Chemistry ◽  
Surface Water Chemistry
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