EDI Staging Environment
We present gridded 8 km-resolution data products of the estimated aboveground biomass, stem density, and basal area of tree taxa at the time of Euro-American settlement of the midwestern United States for the states of Minnesota, Wisconsin, Michigan, Illinois, and Indiana. The data come from settlement-era Public Land Survey (PLS) data (ca. 0.8-km resolution) of trees recorded by land surveyors. The surveyor notes have been transcribed, cleaned, and processed to estimate aboveground biomass (megagrams per hectare), stem density (stems greater than or equal 8 inches DBH per hectare), and basal area (square meters per hectare) at individual points on the landscape. The point-level data are then aggregated within grid cells and statistically smoothed using a statistical model that accounts for zero-inflated continuous data with smoothing based on generalized additive modeling techniques and approximate Bayesian uncertainty estimates. We expect this data product to be useful for understanding the state of vegetation in the midwestern United States prior to large-scale Euro-American settlement. In addition to specific regional questions, the data product can serve as a baseline against which to investigate how forests and ecosystems change after intensive settlement. The data products (including both raw [Level 1: averages of point level values within each grid cell] and statistically smoothed estimates [Level 2] at the 8-km scale) are being made available at the LTER network data portal as version 1.0. This material is based upon work supported by the National Science Foundation under grants #DEB-1241874, 1241868, 1241870, 1241851, 1241891, 1241846, 1241856, 1241930.
EDI is a collaboration between the University of New Mexico and the University of Wisconsin – Madison, Center for Limnology:
