Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Titre : Microclimates Mediate Water Fluxes from Vegetation

Auteur : Bilir, Teresa Eren. 

Université de soutenance : University of California, Berkeley

Grade : Doctor of Philosophy in Environmental Science, Policy, and Management 2022

Résumé partiel
Earth is the blue planet, unique in our solar system for its ability to sustain a water cycle that spans three phases : solid (ice), liquid (water), and gas (water vapor). The global cycling of water between the earth’s land surface, subsurface, cryosphere, oceans, and atmosphere is fundamental to earth’s radiative balance and energy transport, and sustaining life in every ecosystem. The global water cycle is also a driver of feedbacks between the land surface and the atmosphere over a range of scales, from minute exchanges through stomata on leaves to eco-climate teleconnections wherein continental-scale changes in vegetation cover could alter climate and ecosystem dynamics in a different hemisphere.

At fine spatial scales, microclimatic variation influences the strength and type of these feedbacks, and plays a role in determining patterns of vegetation vulnerability. Microclimates arise in hilly terrains from the midlatitudes to the poles due to differences in solar gain on opposing slopes. This leads to differences in the daily timing, duration, and intensity of sunlight exposure, and variable associations between sunlight and other climatic variables such as air temperature and humidity. These slope-aspect-induced climate differences are ecologically important, and impact vegetation-mediated water balance between the earth surface and the atmosphere.

This thesis investigates climate–vegetation feedbacks arising from the impact of microclimate variation on water fluxes from forest vegetation. The primary investigation approach was a field study based at the University of California’s Angelo Coast Range Reserve in Northern California. There, I installed sensors to collect continuous high-resolution (∼5 minutes) data in a study of water flux differences in Pacific madrone (Arbutus menziesii) and Douglas fir (Pseudotsuga menziesii) across a slope-induced microclimatic gradient from spring 2018 to fall 2020. The field site has a Mediterranean climate with wet winters and dry summers

Présentation et version intégrale (ProQuest)