Infrastructure to measure and manipulate drought and warming impacts in Mediterranean systems

University Of California-Davis, Davis CA

Investigators

Abstract

Between 2012 and 2014, the California Floristic Province, a priority hotspot for global biodiversity conservation, has experienced the hottest and driest period on record. Evidence is rapidly mounting indicating that these co-occurring periods of precipitation deficit and warm temperatures are likely to increase over the next century and pose a serious threat to biodiversity and the critical services these ecosystems provide society. While the impacts of a warmer and drier future on these and similar ecosystems are expected to be severe, some species and ecological communities may be more vulnerable to these changes than others. Understanding the factors that drive differences in vulnerability is one of the preeminent scientific and societal challenges of our time as this knowledge is essential for prioritizing conservation efforts and for identifying practical adaptation strategies that can conserve or enhance critical services these ecosystems provide society under changing environmental conditions. To address this need, this project develops linked infrastructure at the UC Sierra Foothill Research and Extension Center (SFREC) that will allow researchers to (1) measure how exposure to drought and elevated air temperatures varies over time and across the topographically complex landscapes and (2) experimentally apply different levels of drought and air temperature to key plant communities and species that are critical drivers of services these ecosystems provide society. The infrastructure developed here not only allows multiple lines of new research around drought and warming impacts to be pursued but does so while greatly reducing start-up costs for researchers, thus overcoming a major barrier to greater participation in climate change research by students and scientists from underrepresented institutions. This project also adds key capacity to expand K-12 STEM education and science content training for educators to diverse and rural agricultural communities in northern California having markedly less access to STEM and science education training opportunities than most areas in the state. While the need to deploy an integrated framework for assessing species vulnerability to climate change is widely acknowledged, globally we have minimal field infrastructure that allows us to simultaneously assess impacts due to climate change exposure and impacts due to climate change sensitivity. To address this need, this project establishes linked research infrastructure distributed across the University of California Sierra Foothill Research and Extension Center (SFREC, http://sfrec.ucanr.edu/) that supports continuous measurements on local exposure to climate change and experimental assessment of multiple factors that drive variation in species sensitivity to these changes. Specifically, this research infrastructure includes (1) a distributed wireless network of meteorological and hydrological sensors to measure and model how regional climate exposure is modified by topographic complexity and (2) a distributed field system for experimental manipulations of precipitation and warming that will provide researchers extensive ability to develop mechanistic understanding of factors (e.g. ecophysiological traits, genetic diversity, plasticity) and interactions (competition, biological invasions, soil microbial community) that ultimately drive variation in species and population sensitivity to climate change. The wireless mesh system will be constructed using commercially available wireless technology and environmental sensors. This system also will allow future researchers the ability to add project specific sensors. For experimental manipulations of field conditions, experimental warming will be achieved using large (7 x 7 m) passive warming structures designed to minimizes airflow disruption and provide sufficient space for multiple experiments to be run simultaneously in a cost-effective manner. Precipitation manipulations will be achieved using a polycarbonate roof system coupled to an automated precipitation redistribution system that will allow researchers to increase or decrease precipitation inputs relative to ambient inputs on an hourly basis. This infrastructure extends our current global research capacity by providing researchers an experimental framework to establish mechanistic and causal linkages between regional climate change and local changes in biodiversity and ecosystem function. This research infrastructure also provides an unparalleled ability to test and model conservation benefits of various biodiversity management tools and strategies. Ultimately this infrastructure should support major positive steps for biodiversity conservation in these and similar Mediterranean systems across the globe.