Impacts and Adaptation 8.3.1. Nonforest ecosystems are the source of most surface flow and aquifer recharge in the western Great Plains and the extreme northern regions of North America. Municipal, agricultural, and industrial sectors in these regions depend on nonforest ecosystems for the quantity and quality of water required for economic sustainability. The quality and quantity of water derived from nonforest ecosystems depend on the management these lands receive and the average annual and extreme climatic events they encounter. Nontidal wetlands in North America include a variety of ecosystems such as bogs, fens, swamps, marshes, and floodplains.
Classification systems are many and varied.
These wetlands are distributed throughout North America, principally in a band extending from the New England states to Alaska. See Section 8.3.3 for a more detailed discussion of wetlands impacts. Rangelands are characterized by native and introduced vegetation predominantly grasses, grasslike plants, forbs, shrubs, and scattered trees. The associated ecosystems are complex and are affected by many interacting biotic and abiotic components, and their health depends on the interaction of climate, soils, species competition, fire, grazing, and management. Researchers also believe that the impacts of CO 2 enrichment and shifts in temperature and precipitation regimes are likely to be greatest when they are reinforced by other destabilizing forces.