Sediment Characteristics and Infauna of Deltaic Mudflats Along the Alaskan Beaufort Sea.

摘要

Migratory shorebirds are dependent on benthic invertebrate food sources of estuarine Arctic river deltas. The importance of these systems as shorebird feeding grounds is based on their ability to support invertebrate prey species that have continuous access to high quality food (carbon) resources during the summer open-water period. We collected sediment samples from deltaic mudlflats at three Beaufort Sea deltas (Jago, Okpilak/Hulahula, and Canning river deltas) in August 2010 and 2011. From these sediment samples, we quantified sediment chlorophyll, salinity, organic carbon, ammonium, and sediment grain size and described their characteristics at the three sites. At the same time, we collected sediment core samples for quantifying spatial and temporal distribution of bacterial assemblages, meiofauna, and macrofauna. Polymerase chain reaction (PCR) analysis was used to census microbial populations (bacteria archaea, and eukarya) in the sediments. Organic composition of the sediments was related to river sources of organic matter based on stable carbon isotopic measurements of sediments to identify the relative importance of allochthonous and autochthonous carbon sources.