Congrats Dr. Tane!

Post date: Mar 13, 2018 11:40:15 PM

Zach Tane successfully defended his dissertation and celebrated with the lab and family afterwards at Beachside. Congratulations Dr. Zachary Tane!

Dissertation Title: Using Remote Sensing to Characterize Conifer Mortality during a Severe Drought in the Sierra Nevada

Abstract: Between 2012 and 2016, the southern Sierra Nevada experienced an extreme period of drought and high temperatures. In the latter years of this global-change-type drought, epidemic levels of tree mortality spread across the area. Remote sensing was used to gain an understanding of the impact and drivers of tree mortality. In Soaproot Saddle, a 2,240 ha watershed in the southern Sierra Nevada, a combination of high spatial resolution airborne imaging spectroscopy and lidar acquired in 2013 was used to identify tree crown's locations, species, and height. With this information, the survival of individual trees in 2016 was investigated. I find ponderosa pine (Pinus ponderosa) to be disproportionally impacted by the drought, with implications for future species compositions in the area. Across the southern Sierra Nevada, I also used imaging spectroscopy data that was simulated to be equivalent to what a spaceborne imaging spectrometer would acquire to map red stage tree mortality. I demonstrated that a simulated spaceborne imaging spectrometer would be able to more accurately identify the location of red stage tree mortality compared to existing multispectral satellites, such as Landsat. Finally, both within the 2,240 ha watershed and across the southern Sierra Nevada, the factors that distinguished conifers that were alive in 2016 from conifers that had recently died in 2016 were examined. Trees that survived were typically located in stands with tree species and height class heterogeneity. Stands in wetter, cooler parts of the Sierra Nevada during the drought were also more likely to survive.