At the May meeting Dr. Emanuel Ziaco of the University of Nevada, Reno (UNR) will be presenting his research on tree-rings and woody cells: revealing past and present climatic signal in xylem anatomical structure of conifers species in the western USA. Our previously announced presentation by Eric Morway of the US Geologic Survey has had to be rescheduled.
Mountain ecosystems in the western United States host some of the most iconic long-lived conifer species, which have provided millennia-long tree-ring records of climatic and environmental changes. Increasing temperature and moisture stress forecasted by greenhouse warming simulations for the American west pose a vital threat for the survival of these natural systems, affecting plant phenology, species distribution, and vegetation dynamics. Understanding the mechanistic linkages between climate and tree growth at seasonal, sub-seasonal or daily timescales has therefore become a crucial challenge for both plant physiologists and palaeoclimatologists. Dr. Ziaco will present the results of four years of field research on cambial phenology (i.e., onset/offset of wood formation), xylem anatomy, and plant-water relationships (i.e. circadian cycles of stem size variation) conducted on Great Basin conifer species: bristlecone pine (Pinus longaeva D.K. Bailey), ponderosa pine (Pinus ponderosa var. scopulorum Engelm.), limber pine (Pinus flexilis E. James), pinyon pine (Pinus monophylla Torr. & Frém.), and Douglas fir (Pseudotsuga menziesii (Mirb.) Franco). Using a combination of PRISM data and higher-resolution data from a gradient-based network of monitoring stations (the Nevada Climate-ecohydrological Assessment Network – NevCAN), they identified the main climatic drivers of seasonal wood formation and stem water usage for these foundation species, including the effect of climatic patterns at the regional (i.e. the North American Monsoon) and global (i.e. ENSO, the El Niño/Southern Oscillation) levels. Improved comprehension of plant morpho-physiological adjustments in response to environmental stressors at the cellular level allows us to integrate existing ring-width based climatic reconstructions with multi-centennial chronologies of anatomical parameters to capture the footprint of extreme episodes (i.e. severe droughts) on the hydraulic architecture of conifer species.
Dr. Ziaco is a broadly trained forest scientist with a scientific background in forest ecology and dendroecology, but he has also acquired experience in wood anatomy, cellular dynamics of xylem formation, and climate-ecosystem interactions during my years as a postdoctoral scholar at the University of Nevada, Reno. He is currently a co-Principal Investigator of a grant funded by the National Science Foundation to study relationships between regional climatic patterns, wood anatomy, and hydraulic architecture of conifer species in the western US, focused on the impacts of El Niño/Southern Oscillation on forest ecosystems of the western USA.
He has conducted field studies in Europe and in the Great Basin of the United States, developing successful international collaborations with research groups from the US, Canada, Germany and Italy, which have led to multiple publications in peer-reviewed journals. His work in old-growth and unmanaged stands of Southern Europe investigated forest structural dynamics and disturbance regimes to develop guidelines for forest restoration and sustainable silvicultural practices, with particular attention to the management of deadwood and habitat trees to sustain forest ecosystem services and biodiversity conservation.
Since 2013 he has actively collaborated in establishing and maintaining a research program in wood anatomy and cellular dendroclimatology in the western United States, in close connection with the Nevada Climate-ecohydrological Assessment Network (NevCAN). This system of long-term mountain observatories in eastern and southern Nevada was established to assess the adaptation of Great Basin conifer species to drought, and their vulnerability under future scenarios of greenhouse warming. I have also experience in environmental education related to forests and ecosystem services, acquired during my professional and teaching activity. His current (and future) research on xylogenesis and wood anatomy integrate and improve our understanding of ecosystem functioning, bridging the gap between tree physiology, structure of plant communities and stand dynamics, helping to preserve the productive, recreational, and biological value of forest species in the Western United States.
On the corporate front the draft bylaws (available here) will be up for approval and the ABC will be selecting its initial directors. If you are concerned about forest and watershed health, and sustainable local economy please consider serving. Thanks to Michael Barton for his work on preparing the draft bylaws. An application has been filed for an Alpine County Small Grants Program grant to help us with the cost of our monthly meetings and the filing of an application for a 501(c)(3) nonprofit designation.
The May meeting is scheduled for Tuesday May 1st at 6:00 pm at Turtle Rock Park.