Photosynthetic Capacity within the Phantom Gas Field Project

Anthropogenic noise has proven detrimental to organisms like bats, owls, and certain other species whose hunting or navigation success is affected by unnatural sound. However, few studies have quantified the effects of noise pollution across multiple trophic levels. Our study is quantifying the impacts of human noise on insect abundance and herbivory, and plant physiology, using experimental noise stations compared to quiet control sites in the sagebrush steppe southwest of Boise, Idaho. I am measuring variation in leaf chlorophyll fluorescence and Normalized Difference Vegetation Index (NDVI). Both of these measurements are indirect measurements of photosynthetic capacity. We hypothesized that shrubs in “noise ON” sites will have increased insect abundance and herbivory (leaf damage), and thus declines in photosynthetic capacity, due to decreased predation on insects by birds and bats at these sites. Preliminary data suggest that photosynthetic capacity is slightly less at "noise ON" sites compared to control sites.