HERD LAKE: THE RECENT SEDIMENT HISTORY OF A VARVED, LANDSLIDE-DAMMED LAKE
Here we present the 88-year record of downcore changes in these indicators, focusing primarily on the transitions in the diatom assemblages, elemental concentrations, and phosphorus geochemistry. Together our environmental indicators from the lake sediments highlight interesting interactions between the landscape, watershed, and the lake. Correlation in the record between burial of oxide-bound phosphorus and variation in the relative abundance of a large-diameter planktonic diatom species suggests that these two indicators are closely associated with seasonal variability in the intensity of convective lake mixing. The record of percent carbon, percent nitrogen, organic phosphorus, and total phosphorus all display nearly identical downcore patterns, including a long-term trend of increasing nutrient burial over the last century. Using this rich collection of environmental indicators, we compare our high-resolution record to regional and local historical climatological data to explore potential teleconnections that may explain the long-term trends in variability observed.