Abstract Detail

Forest Tree Responses to a Changing Climate

Sinervo, Barry [1], Pittermann, Jarmila [2], Santos, Juan [3], Miles, Donald [4], Sites, Jack [5], Bauer, Aaron [6], Ammon, Corl [1], Raymond, Huey [7].

Plant mortality and beyond: Quantifying climate-forced extinction risks for lizards, amphibians, and plants.

Climate change is altering global patterns of temperature and rainfall. These environmental changes are transforming plant communities, which in turn may result in local extinctions of many vertebrate species. For example, when faced with prolonged water deficit or high temperatures, trees may be unable to draw sufficient water from the soil, and will produce fewer leaves or drop existing foliage. Diminished leaf cover allows more sunlight to reach the ground, further amplifying local warming and water stress not only for understory plants, but also for the vertebrates that rely on them for shade or habitat. This study hypothesizes that many ectotherms are undergoing demographic collapse because rising temperatures are stressful, resulting in restrictions in activity time that reduce energy gains below levels needed for reproduction. Indeed, evidence suggests that diminished vegetation cover due to drought-induced plant mortality increases the physiological stress experienced by ectotherms. The goal of this project is to first identify the physiological mechanisms responsible for drought-induced vegetation decline by capturing tree species' in situ water relations, and to link this information to species' resistance to hydraulic failure. This work is on-going in Africa, Europe, North and South America, along with broad-scale sampling of lizard and amphibian thermal biology and demography. These regional studies will then be used to generate comprehensive data sets that integrate changes in temperature, rainfall, and plant die-off to generate a microclimate envelope (that includes soil moisture and temperature) in which animals may or may not persist based on their estimated thermal preference behaviour. Once ground-truthed with ectotherm demography, models of plant-animal dependencies can be used to predict ectotherm distributions and extinctions under future climate-change scenarios that include shifts in temperature and precipitation. Similarly, these calibrated models can be applied to both plant and animal fossils to infer evolutionary trajectories in form and function during Cenozoic climatic deterioration. Large-scale collaborative projects between plant and animal biologists will lead to more synthetic assessments of local community responses across multiple biomes.

1 - University of California, Ecology and Evolutionary Biology, 1156 High St, Santa Cruz, CA, 95064, USA
2 - University Of California, Integrative Biology, 1156 High Street, Santa Cruz, CA, 95064, USA
3 - Brigham Young University, Biology, A-285 Asb, Provo, UT, 84602, USA
4 - Ohio University, Biological Sciences, Athens, OH, 45701, USA
5 - Brigham Young University, Department of Biology, A-285 Asb, Provo, UT, 84602, USA
6 - Villanova University, Biology Department, 800 Lancaster Avenue, Villanova, PA, 19085, USA
7 - University of Washington, Seattle, Biology Department, Box 351800, Seattle, WA, 98195, USA

Keywords:
drought
climate change
vegetation dieback
plant hydraulics
physiology
plant physiology
ectotherms.

Presentation Type: Symposium Presentation
Session: SY13
Location: Hall A/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 10:45 AM
Number: SY13007
Abstract ID:538
Candidate for Awards:None