LTREB: Long-term provenance study of phenotypic plasticity, local adaptation, and response to climate in Quercus (Q-PLAD)

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

This study provides a unique analysis of the response of a widespread California endemic tree, valley oak (Quercus lobata), to a changing climate. Climate is a critical component of the environments where organisms live. Trees face unique challenges because they are long-lived and once they become established, they must either tolerate the local climate or die. Given the ecological, economic, and inherent value of trees and forested landscapes, understanding how trees respond and adapt to new or changing conditions is crucial to inform conservation and management strategies. Such information can only be gained through long-term experiments such as this project, where growth, survival, and seed production data will be collected on a large set of valley oak trees, grown from acorns gathered from throughout the species range and planted into two large field plots. Also, the results of this study will provide training of students from groups that are underrepresented in STEM. Ten years ago, a long-term study of Quercus lobata, was established using 11,000 acorns sampled from 95 localities and 672 maternal trees from across the species’ range. This project continues this long-term study, dubbed Q-PLAD, to determine how specific climate-associated traits, growth, survival, and seed production vary within and among half-sib families in relation to local and source climatic conditions. Over the next 5-10 years, the project will: (1) establish an integrated data system to archive existing and future datasets and facilitate public data availability and analysis; (2) robustly test hypotheses about plasticity in leaf and flower emergence and climate-associated local adaptation in those traits; (3) conduct focal experiments to assess plasticity and adaptation in climate-associated functional traits; and (4) determine the extent of local adaptation in various fitness components associated with climate. Q-PLAD addresses fundamental questions in evolutionary biology concerning the evolution of phenotypic plasticity and local adaptation. In addition, these findings will enhance our understanding of how to sustain the health of tree populations that protect key habitats and ensures carbon capture to help mitigate human-caused carbon emissions. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.