The Comparison of Two Semi-permanent Wetlands in the Missouri Coteau, ND, to Determine How Each Recorded Climate
My study compared components from the sediment records in two semi-permanent wetlands on the Missouri Coteau in North Dakota to determine how adjacent, but hydrologically different settings record climate. Both wetlands receive the bulk of their waters from spring rains and snow melt and are underlain with glacial till. However, one wetland loses most of its water by evaporation and the other loses some water by outflow. Yet, because the hydrologic budgets of these wetlands respond immediately to climate change (seasonal, annual, decadal, longer) and because climate input to both wetlands is identical, we would expect the components of their sediments to tell a similar climate story.
Short cores from the centers of the two wetlands (P1 and P8) do not have similar records: (1) An order of magnitude difference in magnetic susceptibility. (2) Size of magnetic particles. (3) Abundance of organic material. These proxies contribute to different records of climate between the two wetlands.
Despite similarities in these two wetlands physical, geological, and
climatic settings, their sedimentary records do not share a common climate
story. The primary reason for the differences between the records
can be attributed to the differences in the hydrology of each wetland.
Therefore, climate studies that derive their data from proxies in the sediments
of lakes and wetlands need to understand how the hydrology of the system
modifies the climate signal.