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Drivers of Change
From "Ecological Forecasting: Agenda for the Future" published by Committee on Environment and Natural Resources Subcommittee on Ecological Systems.
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These five key causes of ecological change (Extreme Natural Events, Climate Change, Land and Resource Use, Pollution and Invasive Species) play out and interact on a wide range of time and space scales. Even this oversimplified graph suggests that one of the greatest forecast challenges will be to predict the cumulative impacts of multiple stresses.
Extreme Natural Events
Such events include fire, floods, droughts, hurricanes, windstorms, and some toxic algal blooms. While extreme natural events are largely outside the control of natural resource managers, the ability to predict their occurrence and ecosystem effects, as well as their interactions with other causes of change, are important for planning management and response activities to minimize damage and enhance ecosystem resilience.
Climate Change
As certainty about the likelihood and magnitude of climate changes increases, the need for resource managers and policy makers to plan to minimize impacts on species, ecosystems, and ecological goods and services becomes more urgent. Current needs include forecasts of the interaction of climate change and variability with other stresses on ecological goods and services, particularly the distribution of species and the availability of clean water.
Land and Resource Use
Ecosystem changes take place in the context of ongoing changes in land and resource use. Forecasts of the far-reaching implications of these shifts on ecosystems, and their impacts on society, are needed. Current needs include forecasts of changes in the health and productivity of the natural and managed ecosystems that are critical in providing food and fiber to the U.S. economy - especially agricultural, forest, and rangeland ecosystems.
Pollution
Concerns about the presence of potentially harmful chemicals and excess nutrients in the environment remain a top concern. Current needs include forecasts of the effects of air pollution and land-based activities (for example, agricultural production, forest harvest) on terrestrial, freshwater and marine ecosystems.
Invasive species
Invasive species are species that are introduced intentionally or unintentionally from other areas and are capable of spreading rapidly and replacing native species. These invaders exist in nearly all U.S ecosystems, pose potential threats to the integrity of our nation's landscapes, biodiversity, and ecosystems, and annually cost billions of dollars to control. Current needs include forecasts of the introduction, spread, and ecological effects of potential and already-introduced species.
Interactive Effects
Most ecosystems throughout the United States are subject to multiple causes of ecological change. For example, an extreme natural event (perhaps fire) may open the door for new species invasions, and the success of that invader may be enhanced by altered climate (new precipitation and temperature patterns), the extent to which the land and related resources are used, and the chemical condition of the environment being invaded (pollution). Building the ability to forecast the cumulative effects of these multiple stresses is one of ecology's most significant challenges.
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