This project investigates how four different terrestrial ecosystems from the southwestern US, from high desert grassland to subalpine prairie, respond to increased temperature and altered precipitation, using experimental treatments that simulate the expected future climate in 100 years. These treatments have been imposed for nearly a decade and are planned to continue for a decade more, creating a long-term climate change experiment across multiple ecosystem types. The goals of this project are to test whether the initial responses of these ecosystems to simulated climate change are consistent over time, or whether they change over time as the ecosystems adjust to the new climatic conditions. The responses that will be documented include plant growth, carbon cycling and storage, and soil release of greenhouse gases like methane and nitrous oxide.
This project is important because climate change affects terrestrial ecosystems, but also because these ecosystems affect climate. Therefore, how ecosystems respond will influence the pace and trajectory of future changes in the climate system. The project fills a key knowledge gap, because long-term responses of ecosystems to climate change are especially important for understanding the future climate, but these responses are difficult to document, requiring experiments that last for decades. The project will integrate global change research with science education through provision of competitive undergraduate internships. Outreach activities organized through local conservation organizations will place this research in a broad context accessible to the general public.