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

Principal Investigator: Jeremy James

Between 2012 and 2014 the California Floristic Province, a priority hot spot 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 human caused, likely to increase over the next century, and drive major changes in drought duration and intensity.

We have submitted to NSF Field Station and Marine Lab Facilities program a proposal to build shared infrastructure that supports development of an integrated understanding of how drought and warming will impact biodiversity and function of Mediterranean ecosystems.

This includes:

1. a distributed wireless sensor network that provides continuous measurements of topoclimatic variation in soil moisture deficit and temperature profiles across the 2,428 ha University of California Sierra Foothill Research and Extension Center (SFREC),
2. a distributed infrastructure that allows automated, economical and large-scale manipulation of precipitation deficit and warming in the field.

The wireless network provides critical long-term data on topoclimatic exposure to drought and warming and a simple means for researchers to add project-specific sensors across the landscape.

The infrastructure allowing simultaneous manipulation of drought and warming in the field provides unmatched capacity to mechanistically evaluate factors (e.g. ecophysiological traits, genetic diversity) and interactions (e.g. competition, biological invasions) that drive variation in plant population, species and community sensitivity to drought and warming.

While climate change impacts on biological systems are expected to be severe, these impacts are not expected to be evenly distributed among populations, species, or communities. Instead, impacts of regional climate change on biodiversity will be mediated by local exposure to climate change, species-specific sensitivity to climate change, and how adaptive capacity and biotic interactions alter species sensitivity to rapidly changing environmental conditions.

While the need for an integrated understanding of how these factors drive climate change impacts on biodiversity is extensively recognized, across the globe we have minimal field infrastructure that allows us to simultaneously assess impacts due to climate change exposure and impacts due to climate change sensitivity.

The infrastructure proposed here represents a major step toward filling this gap, allowing researchers to test hypotheses related to processes and mechanisms driving biodiversity response to a warmer and drier future and providing unparalleled ability to test and model conservation benefits of various biodiversity management tools and strategies. Ultimately this integrated infrastructure should support major positive steps for biodiversity conservation in these and similar Mediterranean systems across the globe.