Biogenic-silica content (wet-alkaline extraction) quantifies the weight percent of algal remains in sediment. It can be used to infer past changes in aquatic productivity and, in some cases, serves as a useful climate proxy. Sediment can be analyzed rapidly at high resolution. For example, McKay et al. (2008) found that BSi content in lake sediment from south-central Alaska was correlated with summer air temperature. BSi is extracted from ~100 mg of sediment with 10% Na2CO3 and the concentration is determined with molybdate-blue reduction and spectrophotometry following the procedure of Mortlock and Froelich (1989). Contact the lab for pricing information.
Sedimentary Records of Environmental Change Lab
School of Earth and Sustainability
