Authors: Ben Crawford*, University of Colorado - Denver, Kathy Kelsey, University of Colorado Denver, Amanda Charobee, University of Colorado Denver
Topics: Physical Geography, Biogeography, Remote Sensing
Keywords: urban, vegetation, phenology
Session Type: Virtual Poster
Start / End Time: 8:00 AM / 9:15 AM
Room: Virtual 51
Presentation File: Download
Urban vegetation is growing in importance as cities use ‘green infrastructure’ to mitigate the effects of climate change and improve human health. However, urban vegetation experiences a diverse range of environmental conditions compared to vegetation in rural areas, potentially leading to differences in growing season timing and length. Here, we investigate physical controls on urban vegetation phenology and timing in a semi-arid city (Denver, CO, USA) using remotely sensed vegetation, surface temperature, and land cover datasets. Within the metropolitan region study area, satellite-based vegetation index measurements (NDVI) indicate growing season length is variable on sub-neighborhood spatial scales. Preliminary results suggest this is largely due to differences in the timing of fall senescence, as opposed to early season growth. Areas with substantial fractions of irrigated land cover tend to remain greener longer, while un-irrigated and warmer areas are correlated with an earlier end to the growing season. In turn, vegetation also regulates surface temperatures, with tree canopy cover and irrigated areas associated with cooler surfaces. These urban growing season dynamics and temperature-vegetation feedbacks have implications for vegetation management strategies to maximize ecosystem services in water-limited environments.