Dissolved Organic Carbon Cycling in Forested Watersheds: A Carbon Isotope Approach

摘要: Dissolved organic carbon (DOC) is important in the acid-base chemistry of acid-sensitive freshwater systems; complexation, mobility, persistence, and toxicity metals other pollutants; lake metabolism. Carbon isotopes (13C 14C) are used to study origin, transport, fate DOC a softwater catchment central Ontario. Precipitation, soil percolates, groundwaters, stream, beaver pond, waters, sediment pore water were characterized chemically isotopically. In addition total DOC, isotopic measurements made on humic fulvic fractions. The net sink for DOC. Δ14C results indicate that turnover time most streams, lakes, wetlands fast, less than 40 years, same scale as changes acidic deposition. groundwaters composed older surface indicating extensive cycling upper zone or aquifer.