Observing earth from Above at ESA

We'll present two posters this summer at the Ecological Society of America's annual meeting in Long Beach, California.

The first poster, entitled "Scalable approaches to teaching a diverse new generation of scientists to observe Earth from above" will present the project as a whole, including results from our initial evaluation and assessment based on the course we taught in fall 2023 at Chapman University. We'll also launch this website to the public.

The second poster, entitled "The thermal limits of native plant species in California Coastal Scrub," is based on a course-based undergraduate research experience carried out in spring 2024 in an upper-division plant ecophysiology course at Chapman University. Students in the lab blended field research establishing leaf thermal tolerances among species, measurements of plant functional traits hypothesized to be related to leaf thermal tolerances, and used ECOSTRESS to study current land surface temperatures at the field sites where we worked. We were very fortunate to collaborate closely with the Irvine Ranch Conservancy to work on lands they manage. For all of their hard work this spring, the students have earned co-authorship! The abstract is as follows:

High temperatures can negatively impact plant function and have been implicated in plant mortality events around the world. At the same time, it is clear that not all plant species respond equally to heat stress. Differences in plant structure and function among species may mean that some are more resilient than others in the face of high temperatures. To understand variation in plant response to temperature, we sampled structural (e.g., leaf size, angle and pubescence) and functional (e.g., leaf stomatal conductance, Fv/Fm, thermal tolerance) traits among 12 common native plant species occurring within the protected lands managed by Irvine Ranch Conservancy in Southern California. Our objective was to identify species that may be more or less resilient to high temperatures and to understand what structural and functional traits may underlie any differences we observed. A five-year record derived from satellite remote sensing (ECOSTRESS) indicates that land surface temperatures at the site can peak at >50 ℃. Leaf temperature was lower than air temperature (median difference: 0.62 ℃) in 11 of the 12 species. A lower leaf temperature relative to air temperature was significantly correlated with increasing pubescence (Spearman’s rho = 0.36), but not with leaf angle, size, thickness, or stomatal conductance. Leaf thermal tolerance, as inferred by the temperature at which a species experiences a 50% decrease in chlorophyll fluorescence (T50), averaged 48.8 ℃ and ranged considerably from 46.1 to 54.1 ℃. Land surface temperatures are already occasionally exceeding the T50 of some plant species and the frequency and duration of these high temperature events are likely to increase in the years to come. Our results provide insights into the structural and functional traits that contribute to plant species response to temperature, as well as which species are most likely to be affected by climate change. In turn, such information can be used to inform efforts to conserve and restore resilient plant communities for the future.