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. 2023 Jul 19;131(7):077009. doi: 10.1289/EHP12396

Figure 2.

Figure 2 is a histogram, plotting area of tree harvest (kilometers squared), ranging from 0 to 100 in increments of 25 (left y-axis) and number of human cases, ranging from 0 to 30 in increments of 10 (right y-axis) across year, ranging from 1985 to 2010 in increments of 5 years (x-axis) for probable and confirmed, and confirmed only cases, with values for tree harvest area and number of human cases shown until the year 2014.

The total area of high-and low-confidence tree harvest events occurring within 10km of the eastern human settlement area of Vancouver Island (in gray bars) compared with the number of confirmed (solid black line, n=146) and combined probable and confirmed human cases (dashed black line, n=241) with residences on Vancouver Island. Human cases regardless of travel history are shown. Tree harvests were assigned high or low confidence through a random forest classifier, based on how many votes from individual trees were received for each class type (e.g., tree harvest, fire). The proportion of votes of the second-most voted class (v2) was divided by the proportion of votes of the assigned class (v1). Tree harvests were considered high confidence if v2/v1 was 0.4 and low confidence if v2/v1 was >0.4. Tree harvest data were provided by Hermosilla et al.10 (see https://opendata.nfis.org/mapserver/nfis-change_eng.html). Human settlement area data were mapped using the 2015 raster data set from the European Commission Global Human Settlement–Settlement Model (SMOD) at a 1-km resolution (https://ghsl.jrc.ec.europa.eu/datasets.php). Data for annual tree harvest areas is in Table S4 in the “10km” column. Data for annual human cases is in Table 1.