statistically-estimated tree composition for the northeastern united states at euro-american settlement.we present a gridded 8 km-resolution data product of the estimated composition of tree taxa at the time of euro-american settlement of the northeastern united states and the statistical methodology used to produce the product from trees recorded by land surveyors. composition is defined as the proportion of stems larger than approximately 20 cm diameter at breast height for 22 tree taxa, generally at the genus level. the data come from settlement-era public survey records that are transcribed an ...201626918331
land-use change, not climate, controls organic carbon burial in lakes.lakes are a central component of the carbon cycle, both mineralizing terrestrially derived organic matter and storing substantial amounts of organic carbon (oc) in their sediments. however, the rates and controls on oc burial by lakes remain uncertain, as do the possible effects of future global change processes. to address these issues, we derived oc burial rates in (210)pb-dated sediment cores from 116 small minnesota lakes that cover major climate and land-use gradients. rates for individual ...201323966637
using paleoecology to inform land management as climates change: an example from an oak savanna ecosystem.oak savanna, a transitional ecosystem between open prairie and dense oak forest, was once widespread in minnesota. upon european settlement much of the oak savanna was destroyed. recently, efforts to restore this ecosystem have increased and often include the reintroduction of fire. though fire is known to serve an important role within oak savannas, there are currently few studies which address fire regimes on timescales longer than the last century. this research presents a paleoecological his ...201728921004
the bias and signal attenuation present in conventional pollen-based climate reconstructions as assessed by early climate data from minnesota, usa.the inference of past temperatures from a sedimentary pollen record depends upon the stationarity of the pollen-climate relationship. however, humans have altered vegetation independent of changes to climate, and consequently modern pollen deposition is a product of landscape disturbance and climate, which is different from the dominance of climate-derived processes in the past. this problem could cause serious signal distortion in pollen-based reconstructions. in the north-central united states ...201525602619
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