Hot Spot Analysis Provides a Way to “Drink from the Firehose” of Forest Health Data
These days, massive datasets—collected regularly across the entire country by satellites, from airplanes, and by ground crews—provide vast information about the health of U.S. forests. But how can anyone make sense out of all that data collected from coast to coast? To address this challenge, an Eastern Threat Center cooperator at North Carolina State University developed an approach for quantifying statistically significant geographic hot spots of forest health threats at a continental scale. Called Spatial Association of Scalable Hexagons (SASH), this approach identifies locations where ecological phenomena occur at greater or lower frequencies than expected by chance. SASH, recently described in the journal Landscape Ecology, is useful for understanding macroscale patterns and processes associated with each forest health threat, assessing its ecological and economic impacts, and identifying areas where specific management activities may be needed. The SASH analysis method is a standard component of annual national reports on forest health status and trends across the United States and can be applied easily to other regions and datasets.
Pictured: A map of geographic hot spots of wildland forest fire occurrence density, detected by MODIS satellites in 2015. Areas in red and orange are significant clusters of high fire occurrence density (the number of fire occurrences detected per 100 km2 of forest). Click to enlarge.
References:
Potter, Kevin M.; Koch, Frank H.; Oswalt, Christopher M.; Iannone, Basil V. 2016. Data, data everywhere: detecting spatial patterns in fine-scale ecological information collected across a continent. Landscape Ecology, Vol. 31(1): 18 pages.: 67-84. 10.1007/s10980-015-0295-0
Potter, Kevin M.; Conkling, Barbara L., eds. 2016. Forest health monitoring: national status, trends, and analysis 2015. Gen. Tech. Rep. SRS-213. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 199 p.
Forest Service Partners/Collaborators: Southern Research Station; Forest Health Technology Enterprise Team
External Partners/Collaborators: North Carolina State University; Purdue University
Contact: Kevin Potter
