A rapid and simple method for the extraction of biogenic silica (BSi) in phytolith-poor sediments and soils

Phytoliths can be used to reconstruct human-nature dynamics over the long term (from decennial to centennial and millennial time scales) and may capture activities that cannot be reconstructed through other proxies. Phytoliths consist of fossil biogenic silica (BSi), formed in plant organs and then released into the soil with plant decay. When working in environmental contexts where the phytolith signal is highly diluted, as is the case in environments with a long history of land use, animal-plant interactions and open woody environments, the extraction of phytoliths remains a challenge. To address this issue, we developed an efficient method for the extraction of biogenic silica (BSi) from sediments and soils of contexts characterised by the long-term human and animal presence and disturbance, such as remnants of old agroforestry systems. The method we developed has a number of advantages, including: •An easy and time-efficient methodology to perform (with an overall processing time of 1.5/2 days for a batch of 16 samples)•An extraction method free from dangerous chemicals•A method amenable to non-experts without a prior background in lab extraction procedures.