We have now collected all the sediment cores we need to analyse for sedimentary algal pigments, silicon isotopes and diatom taxonomy. In total, 7 sediment cores have been taken from the bottom of Lake Baikal. These cores were collected from three coring sites, situated along a transect from the Neutrino site to a site near the BPPM (Baikal Pulp and Paper Mill). The furthest coring site was approx. 20 km away on the lake-ice.
We carefully transported the sediment cores back to our laboratory kunk (metal cabin), to begin carrying out the core extrusions. The cores are approx. 50 cm long, so if we take into account the expected sedimentation rates at Lake Baikal, this means we have captured around the last 500 years. Sediment cores provide excellent natural archives into environmental change, as the top sediments represent modern-day accumulation and the sediments get older as you move down the core.
As it’s important for us to look into changes at a fine temporal scale, we sub-sampled the cores at a high sampling resolution of 2 mm, which roughly equates to sampling every 2 years. Some of our sediment cores contained turbidites, where there is a large increase in sedimentation, and our sampling resolution was decreased to 5 mm through these depositional episodes.
This took a couple of days and some very late nights to get all the work done…but to help us along we had many ice and geomorphology-related music tracks playing…
Now that the core extrusion is complete, Ginnie and I will be focussing on water chemistry, filtering for algal pigments and diatoms, as well as nutrient enrichment experiments….more on this to follow shortly!
