River Science at the U.S. Geological Survey (2007) / Chapter Skim
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1 A Rationale for River Science
1 A Rationale for River Science
Pages 15-24
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From page 15... ...
Hydroelectric power, harnessed primarily in the 20th century by the damming and diversion of rivers, helped supply the nation's growing electrical power needs. By the end of the 1970s, dams had been constructed on most of the nation's largest rivers for hydropower, irrigation water, flood control, navigation, and other benefits.
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From page 16... ...
Beginning with deforestation by European settlers for agricultural land use in the 1700s and continuing with urbanization, floodplain cultivation, dam and levee construction, and channelization, human activities have dramatically altered natural flow regimes. These changes have often exacerbated natural flooding, such as when spring snowmelt on the Red, Mississippi, and Missouri Rivers covered large swaths of the continental interior with attendant loss of life and property damage (Barry, 1997; Shelby, 2003)
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From page 17... ...
And in the midst of the Great Depression, the Tennessee Valley Authority was authorized in 1933 to build dams to control floods, improve navigation, provide hydroelectric power, and to develop programs for soil erosion control and reforestation for the rural Southeast. More recently, the national interest in rivers has evolved to include protecting the quality of river systems and their use by aquatic and riparian species, as demonstrated by the passing of the Wild and Scenic Rivers Act, the National Environmental Policy Act, the Clean Water Act, and the Endangered Species Act.
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From page 18... ...
River science is an emerging interdisciplinary endeavor integrating biology, geology, chemistry, and the fluid mechanics and physics governing water and sediment transport. It includes the study of how physical, chemical, and ecological processes interact to influence the form and dynamics of riverine ecosystems and how riverine ecosystems in turn influence these processes across multiple spatial and temporal scales.
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From page 19... ...
For example, to assess how local fish populations might be affected by the deepening of the navigational channel of the lower Mississippi River, fish habitat studies might reasonably be confined to this stretch of river. In contrast, examining how sediment fluxes from the Mississippi River to the Gulf of Mexico have changed with time involves looking at potential sediment sources and transport processes throughout the entire river basin.
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From page 20... ...
GEOLOGICAL SURVEY a. Hydrology Precipitation Evapotranspiration Interception Evapotranspiration Interception Interception Stem Flow Evapotranspiration Through Fall Infiltration Infiltration Interception Overland flow Depression Storage Zone of aeration Overland flow Through Flow Wat Through Flow er ta le Percolation r tab ble Percolation Wate River Zone of saturation b.
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From page 21... ...
21 A RATIONALE FOR RIVER SCIENCE c. Biogeochemistry d.
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From page 22... ...
Rather, the domain and bounds of river science are defined by the process bounds and characteristic spatial and temporal scales that are necessary to realize a predictive understanding. This interdisciplinary, process-based, multiscale approach to studying rivers distinguishes river science as an appropriate and increasingly valuable approach for supporting policy-relevant decision making for the nation.
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From page 23... ...
In what ways do the USGS databases, spanning multiple disciplines, need to be modified to adequately store, manage, and disseminate River Science data in useful ways? (Chapter 5, "Integrated Data Archiving, Dissemination, and Man agement")
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From page 24... ...
Establishment of the recommended reach-scale monitoring sites, and increased work in groundwater and surface-water interactions, imply local intense study of processes. In contrast, recommended river surveying and sediment monitoring programs would be national in scale and might last for many decades or even centuries.
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