Fig. 2: Contemporary aquatic biogeochemistry.
From: Changes in coupled carbon‒nitrogen dynamics in a tundra ecosystem predate post-1950 regional warming
a A comparison of carbon isotopic composition and carbon: nitrogen ratios in modern (core-top) sediment from the five study lakes with tussock peat (moss) and runoff water samples from the Toolik Lake catchment; and b a comparison of the change in sediment N concentrations with the change in nitrogen-isotopic composition between the nineteenth century (1800–1880) and the last 2 decades represented in the cores (1980–2000). The capital letters refer to the first letter of the five study lake names.
