Distributions of pH and chemical components in Mizorogaike, a pond with a floating-mat bog

Abstract

Distribution patterns of pH and concentrations of chemical components were studied in Mizorogaike, a pond with a floating-mat bog, which is naturally acidified by the Sphagnum community. Considering the distribution of pH, sampling sites were selected on the floating mat (two sites), beneath the floating mat (one site), in the open water around the floating mat (two sites), and at the mouths of inflows (two sites). Monthly observations from April 1994 through March 1995 revealed that the distribution patterns of chemical components could be classified into three groups according to their pH dependence: (1) concentrations of dissolved organic carbon, organic phosphorus, aluminum, iron, and manganese increase with decrease in pH; (2) concentrations of dissolved orthophosphate and silicon increase with increase in pH; (3) concentrations of suspended particulate aluminum, iron, manganese, phosphorus, and silicon do not depend on the pH. Thus in Mizorogaike, the distribution of dissolved components depends on the pH.