Spatial Point Patterns of Old-Growth Red Pine
This project examines spatial patterns of mortality of old-growth red pine, Pinus resinosa, forests found in Itasca State Park, Minnesota. Red pine is a commercially valuable species in Minnesota, but little is known about its natural (unmanaged) structure, spatial growth, and spatial mortality patterns. Old-growth data is derived from a five-acre plot established in 1923 within a stand estimated at 90 yrs of age at the time of plot establishment. All trees were stem mapped in 1952 and 2010 and analysis includes two-dimensional current live-tree, current dead-tree, and mortality distributions. In order to test if the patterns of these trees deviate from random, Monte Carlo simulations are needed to compute the Ripley's (K) and Pairwise Correlation Functions. These simulations are processed using the open-source statistical software program R. For the 700-1200 trees in each dataset, twenty different spatial patterns are being investigated, each one consuming 24-30 hours per run on a standard laptop or desktop computer. MSI resources allow the researchers to run these simulations in a timely fashion to critically choose which ones best describe the spatial relationships of red pine in Minnesota.