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Tree Mortality Patterns and Processes
Dying piñon pine (Pinus edulis) with orange needles, due to drought stress and associated bark beetle outbreak, Jemez Mtns., NM. October 2002.
The same view, with grey skeletons of dead piñon pines (Pinus edulis) after the needles have dropped, with surviving green junipers. May 2004.
Science Center Objects
Natural climatic variability, including episodic droughts, has long been known to trigger accelerated tree mortality in forests worldwide, including in the Southwest U.S. Scientific understanding of the process drivers and spatial patterns of tree mortality is surprisingly limited, constraining our ability to model forest responses to projected climate changes. The onset of regional drought since the late 1990s has resulted in extensive die-off episodes of multiple tree species across millions of acres in the Southwest, fostering substantial collaborative tree mortality research in this region. Ongoing tree mortality research in northern New Mexico includes: reconstruction of historic forest dieback patterns; monitoring of forest and woodland demographies (tree mortality and regeneration); experimental determination of physiological thresholds of drought- and heat-induced tree mortality; relationships between tree growth, drought stress, insects/diseases, and mortality; remote-sensing of landscape-scale patterns of forest stress and die-off; documentation of regional, national, and global patterns of forest die-off; and efforts to improve models of tree mortality processes.