SUMMARY
Ecosystems are composed of the plants, animals, people, and other living things that interact with the physical environment around us. We depend on ecosystems to provide food, clean water, air, and materials such as wood and fiber that are vital to everyday life. Ecosystems are also sources of human recreation, mental well-being and inspiration, and protection from natural hazards, while at the same time, support diverse sets of organisms. These many attributes make ecosystems a critical component of societal well-being and a healthy natural world. Currently, however, ecosystems are experiencing and responding to numerous human-induced stressors, with climate change among the primary concerns.
Climate change is increasing air and water temperatures, altering precipitation patterns, intensifying many natural disturbances, affecting species distribution and survival, and changing ocean chemistry, among other impacts. These environmental changes are occurring concurrently with other pressures such as pollution, conversion of natural ecosystems to other land uses, transport and introduction of non-native species, and exploitation of natural resources. Together, these stressors threaten the contributions that species make to ecosystem functioning and the ability of ecosystems to sustain the many benefits—known as ecosystem services—that society has come to rely on.
The rapidity of the changes that are now being observed has raised many questions about ecosystem vulnerability, what future ecosystems will look like, and their long-term ability to sustain the same (or similar) services they provide today. In response to these concerns, researchers are working to improve understanding of the effects of climate change and how ecosystems respond to them, as well as to identify opportunities to manage ecosystems so that they can persist in the face of climate change.
Despite the increasing impacts of climate change, many natural ecosystems have demonstrated a strong ability to withstand and recover from (or be resilient to) climate change and other pressures. Such resilience is more likely when an ecosystem is generally healthy and retains much of its original species diversity, and it can be facilitated through management and conservation measures that utilize both traditional and innovative methods. Collectively, these approaches provide many opportunities to promote restoration and continued ecosystem health, but they also require careful consideration of risks, feasibility, costs, and other tradeoffs that may be necessary when making management decisions.
Ecosystems can also provide nature-based solutions, both for climate change mitigation and for helping society adapt to climate change and reduce the impacts of climate-related disasters. Ecosystems mitigate climate change by removing the heat-trapping greenhouse
“The biosphere is a thin, living film on our planet that exists today only because living organisms that evolved on the planet play an active role in the Earth system.”
—JANET FRANKLIN, University of California, Riverside
gas carbon dioxide from the atmosphere and storing it in biomass and soils on land or in phytoplankton, algae, and sediments in the oceans. Societies also adapt to climate impacts via the many benefits they derive from ecosystems. For example, coastlines can be protected from sea level rise, erosion, and storm surges by the presence of mangrove swamps and wetlands, while inland, erosion can be reduced and flood control increased through the presence of forests.
Research efforts to improve knowledge of nature-based solutions, expand measurement networks, and link natural, physical, and social sciences will advance our understanding of climate change and ecosystem interactions, as well as the societal impact of those interactions. At the same time, ecosystem research has already advanced to a point where it can inform management and policy decisions across a range of anticipated future scenarios. Scientists are already working with diverse groups of stakeholders and decision makers to share and develop this knowledge. These efforts have the goal of facilitating the adoption of best practices that promote ecosystem health and the utilization of nature-based solutions, thereby benefiting the ecosystems themselves and the human communities they support.