Dynamic patterns between development and environmental response in the Nordic region: Sedimentary stratification of...

Interactions between regional development and environmental response presumably differ in the Nordic region from the rest of the world due to the cold climate which leads to higher energy consumption per capita due to heating demands. Meanwhile, a long annual ice-cover period might be likely influence sedimentation dynamics in Nordic lakes, introducing uncertainty into chronological interpretations of regional development using the dating sediment core approach. In Lahti and its vicinity, Finland, 12 glacial lakes were selected to compose a categorical development gradient as forest, rural (agricultural predominance), suburban, and urban in their catchments with three replicate lakes per category. With the ²¹⁰Pb dating, the 12 lakes had sediment cores with a continuous chronology covering approximately the latest 100 years. According to multidimensional variation of 8 anthropogenic and non-degradable metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn), the sediment sections were distinctly classified into the four development categories, especially Zn, Cu, Pb, Cr, and Cd with significant urban characteristics (p < 0.05). Historic records of timber preserving treatments were documented by enriched As, Cu, and Cr in deeper sediment layers of forested lakes. Meanwhile, the sedimentary stratification associated with development, as indicated by anthropogenic metal loadings, clearly recorded regional development patterns in urban lake sediment cores, broadly delineated by an inversed U-shaped Environmental Kuznets Curves (except for As or Ni individually), whereas Cu loadings continued to increase linearly, likely due to vehicular inputs.