COS 106-6 - Long-term ecological research on ecosystem response to climate change

Background/Question/Methods

In this presentation we synthesize emerging findings about ecosystem response to climate change on the 40th anniversary of the U.S. National Science Foundation’s Long-Term Ecological Research (LTER) program. In this analysis, we ask the question how a long-term research perspective facilitates insights on ecosystem response to climate change? At all 28 LTER sites, from the Arctic to Antarctica, we examine air temperature and moisture variability and their effects on disturbance frequency and severity, novel disturbances, altered primary production, enhanced cycling of organic and inorganic matter, and changes in populations and communities.

Results/Conclusions

At nine forest and freshwater LTERs, climate change is affecting species composition and ecosystem structure and function through complex interactions, cascading effects and feedbacks to the climate system resulting from altered streamflow and changes in ecosystem processes such as primary production, carbon storage, water and nutrient cycling, and community dynamics. At eight diverse dryland LTERs, warming combined with multi-decadal drought cycles enhanced floods and wildfires, altered resource availability, plant community structure, and primary production, while severe regional droughts, wildfire and dust events exacerbated air pollution. At six coastal LTERs, sea level rise, and extreme heat and storm events are associated with trends and abrupt changes in primary production, organic matter cycling, and plant and animal communities; coastal ecosystems display dynamic adjustments and illustrate various forms of resilience to climate change. At five marine LTERs, climate modes such as ENSO influence and interact with atmospheric and ocean currents and anthropogenic climate change to affect ecosystem processes including primary production, organic and inorganic matter cycling, and populations and community structure. Although some responses to climate change are shared among diverse ecosystems, most are unique, involving region-specific drivers of change, interactions among multiple climate change drivers, and interactions with other human activities.