We examined the evolution of δ 13 C and δ 15 N of sedimenting particulate organic matter (SPOM) in response to changes in primary productivity, nutrient loading, and plankton dynamics in Lake Lugano between 1985 and 1998. A decreasing δ 13 C reflects the decline of phosphorus loading in Lake Lugano, suggesting that the δ 13 C of SPOM is a good indicator of P availability in the lake, with phosphate being the major control on t...

We determined the Δ 13 C and Δ 15 N of water‐column particulate organic matter (POM), dissolved inorganic carbon, and nitrate, together with water chemistry and phytoplankton biomass and species composition every month in eutrophic Lake Lugano. As primary productivity increased during spring, the Δ 13 C of photic‐zone POM increased from −34‰ to −24‰. This 13 C enrichment reflects decreasing C‐isotope fractionation between orga...

We investigated the annual changes in sediment fluxes at two depths in Lake Lugano, Switzerland, and the associated variations in carbon and nitrogen isotope composition of sedimenting organic matter. The organic carbon and nitrogen fluxes increased by 10 and 20% with depth, respectively, whereas particulate phosphorus fluxes showed an increase of 114% with depth. The δ 13 C and δ 15 N of organic matter showed large seasonal c...