Spatial variations in euphotic zone nitrate utilization based on δ15N in surface sediments

Abstract

 Bulk δ¹⁵N values in surface sediment samples off the southwestern coast of Africa were measured to investigate the biogeochemical processes occurring in the water column. Nitrate concentrations and the degree of utilization of the nitrate pool are the predominant controls on sedimentary δ¹⁵N in the Benguela Current region. Denitrification does not appear to have had an important effect on the δ¹⁵N signal of these sediments and, based on δ¹⁵N and δ¹³C, there is little terrestrial input.