By

Hinckley, Eve-Lyn S.Ìý1

1ÌýEnvironmental Studies, Institute of Arctic and Alpine Research; CU Boulder

California’s wine industry is both a major revenue stream to the State, at $62B per year, and a hydro-biogeochemical manipulation at a grand scale. During the growing (dry) season, winegrowers apply an average of 150 kg of reactive sulfur (S) ha-1Ìý²â°ù-1Ìýto control powdery mildew on the State’s 246,000 ha of vines. Sulfur transported to adjacent aquatic ecosystems may have unintended consequences, including mobilization of heavy metals, such as mercury. Many winegrowers also irrigate vines weekly during the growing season, using water diverted to reservoirs during the dormant (wet) season, or pumped from diminishing groundwater reserves – both increasingly uncertain water supplies. For the past decade, I have collaborated with winegrowers, University of California extension specialists, State Water Board officials, and academic colleagues to study the fate and transport of S in vineyards, from mechanisms operating at sub-meter scales within fields to unintended consequences at the basin scale. In addition, I have worked with winegrowers to quantify and optimize their water use and delivery. In this talk, I will present ongoing projects that my research group and our collaborators are conducting to understand the fate of applied S at local to basin scales, and to inform management and regulation.