A method for a fast and economical in situ collection of pore water in sandy sediments

Marine sediment represents one of the most significant carbon reservoirs. Extraction pore water from uppermost 10 cm column, just below sediment-water interface, in coastal environments can be used to assess rapid chemical changes caused by extensive subsurface biological and reactions. However, owing relatively large grain size some shallow environments, mixes quickly making collection core samples for extraction extremely difficult. Here, we present a simple method utilizing Rhizons collect situ environments. We conducted both ex experiments, using fluorescein as tracer, understand influence overlying during through this method. These experiments also allowed us volume collected before is observed at different vertical depths within column. found that: 1. discarding initial 2 mL minimizes memory effect, 2. avoids interference surrounding column 3. resolution minimum could attained sediments with 1 mm less. finally data two linear transects sites Gulf Aqaba. Results these case studies demonstrate expected patterns high concentrations iron hydrogen sulfide where surface coloration suggested sulfate reduction was dominating, respectively. Both studies, therefore, independently validated Rhizon sampler collecting marine