| Before reaching the ocean, riverine particles from the Loire watershed undergo important chemical transformations in the estuary. This study aims to identify and characterize main processes involving iron (and to a lesser extent Al, Mn, PO4 3- and rare earths elements). Suspended particulate matter data show that 15% of their iron is lost through the estuary. Reductive iron dissolution during deposition periods is likely to explain most of this loss. However, estuarine sediments are characterized by high spatial heterogeneity due to macrofaunal activities. To overcome this difficulty, new methodologies of high resolution and two-dimensional analyses and calculation of pore water, sediment and benthic meiofauna were developed. These developments enable to... |
