Abstract
The excess sulfate yields and median ph values of rivers in Nova Scotia and newfoundland are compared for the periods 1971-73 and 1982-84. The excess sulfate yields were significantly lower in the latter period, while the median ph values of the non-organically dominated rivers were higher. The areal pattern of excess sulfate yields of rivers on newfoundland is in accord with the known pattern of precipitation across the Island. A comparison of data for the Mersey river in Nova Scotia with measured wet deposition of wet excess sulfate reveals that the river yields of excess sulfate are higher than the wet deposition by amounts that are likely due to dry deposition.