Interpretation of Mercury Concentrations in Eight Headwater Lakes in Kejimkujik National Park, (Nova Scotia, Canada) by Use of a Geographic Information System and Statistical Techniques

The concentration of mercury in eight headwater lakes in Kejimkujik National Park correlated positively with total organic carbon, total nitrogens, aluminum, iron and sodium andnegatively with pH and alkalinity (Gran). Annual average mercuryyield of the lakes correlated positively with basin area to lakesurface area ratio, and watershed areas underlain by granite bedrock and glacial deposits and negatively with greywacke bedrock. Principal component analysis indicated that first threecomponents account for 80% of the total variance in the data.The components were related to physiography and geology of the watershed, hardness of water, and atmospheric washouts of longrange transported acidic pollutants and dust particles. Mercuryin the lake waters was associated with the physiography and geology of the watershed. Total organic carbon, aluminum and iron were good predictors of mercury concentration in the lakewaters as were the basin area to lake surface area ratio, and basin areas underlain by granite bedrock, and Halifax slate forthe lake mercury yield. The results showed that transport of mercury from the watershed is a major source of mercury in thestudy lakes.