Abstract Detail


Buehlman, Angela [1], Abbo, Tito [2], Morrison, Glen R [2], Huang, Yi [3], Santiago, Louis [4], Litt, Amy [5].

Examining the Role of Drought Adaptation in Determining the Distribution of Arctostaphylos Species.

Species of the genus Arctostaphylos (Ericaceae), more commonly known as manzanitas, comprise the most diverse of California’s native woody genera. There are currently around 60 recognized species and over 100 taxa. The majority of these species occur in restricted ranges, often limited to very few or a single known population, making them particularly vulnerable to a changing climate and habitat degradation and loss. These narrow endemics are mostly found along the central and northern coasts of California where, while still exposed to a Mediterranean climate, temperatures are overall cooler and precipitation is more abundant compared to more southern and inland locations. Relatively few manzanita species have comparatively wide distributions with established populations in varying habitat types created by topographic diversity along an extensive latitudinal and longitudinal range and moisture gradient. The roles that abiotic factors play in determining the range of a given manzanita species is not clear, nor is it clear how different manzanita species may have adapted to local conditions. This information is valuable for effectively structuring conservation efforts and predicting how species may respond to anticipated changes in climate, particularly heat and water availability.While drought plays an important role in Mediterranean climates, the frequency, duration, and intensity with which it occurs is expected to increase as a result of climate change. To examine the role that adaptation to drought plays in determining the range of manzanita species, we will compare leaf functional traits associated with drought tolerance (leaf size, density, thickness, width, specific leaf area, reflectance/absorbance, and turgor loss point) of six pairs of narrow endemic manzanita species, selected to cover the majority of the latitudinal range of Arctostaphylos from the northern California border with Oregon to Baja California, to those of a widespread species, A. glauca (bigberry manzanita), which has populations in both coastal and desert habitats. Comparison of these traits may indicate the influence of habitat vs relatedness on manzanita species distributions. We will look for significant differences between the mean trait values of these populations/species using MANOVA methods and visualize data using PCA. To determine if the ability of A. glauca to establish populations in such differing habitats is the result of local adaption by given populations or species plasticity, we will complete within-species comparison of populations of A. glauca with correlation analysis to detect variation in traits associated with differences in the temperature and precipitation values of their respective environments.

1 - University of California, Riverside, Botany & Plant Sciences, Riverside, CA, 92521
2 - University of California, Riverside, 900 University Ave, Riverside, CA, 92521, United States
3 - Riverside, CA, United States
4 - University of California, Riverside, Botany & Plant Sciences, Riverside, CA, 92521, USA
5 - University Of California Riverside, Botany Dept, 900 University Ave, Riverside, CA, 92521, United States

functional traits
species distributions.

Presentation Type: Oral Paper
Number: EPH3012
Abstract ID:629
Candidate for Awards:Physiological Section Physiological Section Li-COR Prize,Physiological Section Best Paper Presentation

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