973 resultados para Ivaí River basin


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Rising demand for food, fiber, and biofuels drives expanding irrigation withdrawals from surface water and groundwater. Irrigation efficiency and water savings have become watchwords in response to climate-induced hydrological variability, increasing freshwater demand for other uses including ecosystem water needs, and low economic productivity of irrigation compared to most other uses. We identify three classes of unintended consequences, presented here as paradoxes. Ever-tighter cycling of water has been shown to increase resource use, an example of the efficiency paradox. In the absence of effective policy to constrain irrigated-area expansion using "saved water", efficiency can aggravate scarcity, deteriorate resource quality, and impair river basin resilience through loss of flexibility and redundancy. Water scarcity and salinity effects in the lower reaches of basins (symptomatic of the scale paradox) may partly be offset over the short-term through groundwater pumping or increasing surface water storage capacity. However, declining ecological flows and increasing salinity have important implications for riparian and estuarine ecosystems and for non-irrigation human uses of water including urban supply and energy generation, examples of the sectoral paradox. This paper briefly considers three regional contexts with broadly similar climatic and water-resource conditions – central Chile, southwestern US, and south-central Spain – where irrigation efficiency directly influences basin resilience. The comparison leads to more generic insights on water policy in relation to irrigation efficiency and emerging or overdue needs for environmental protection.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study evaluated whether development of the Colorado River system has exceeded sustainability by comparing the trends in water use in the Colorado River. Two sustainable areas were identified in the upper basin and one in the lower-- the mainstream Colorado River, Green and Yampa rivers, and the Little Colorado River. These areas are also high priority recovery areas for four endangered fishes and protected by critical habitat provisions of the ESA. Unfortunately, the endangered fishes are declining because of habitat destruction and non-native species. If increasing water demand causes the fishes to go extinct the few sustainable areas will be lost. It will take careful management of the endangered fishes and water users to ensure these areas are maintained.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This layer is a georeferenced raster image of the historic paper map entitled: Proposed Charles River park, engraved for C. Davenport. It was published ca. 1880. Scale [ca. 1:21,100]. Covers the Charles River Basin and surrounding portions of Boston and Cambridge, Massachusetts. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Massachusetts State Plane Coordinate System, Mainland Zone (in Feet) (Fipszone 2001). All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, or other information associated with the principal map. This map shows features such as roads, railroads, drainage, selected public buildings, parks, and more. Includes table of areas and insets: View from the foot of Mt. Vernon St. -- [Map of Boston and vicinity]. This layer is part of a selection of digitally scanned and georeferenced historic maps of Massachusetts from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of regions, originators, ground condition dates (1755-1922), scales, and purposes. The digitized selection includes maps of: the state, Massachusetts counties, town surveys, coastal features, real property, parks, cemeteries, railroads, roads, public works projects, etc.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This layer is a georeferenced raster image of the historic paper map entitled: A map of the Congo basin and adjoining territories : shewing the extent of the Congo Free State, Henry M. Stanley. It was published by Harper & Brothers in 1885. Scale [ca. 1:3,000,000]. This layer is image 1 of 2 total images of the two sheet source map, representing the western portion of the map. Covers a portion of Central Africa.The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Lambert Conformal Conic projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, shoreline features, and more. Relief shown by hachures and spot heights.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This layer is a georeferenced raster image of the historic paper map entitled: A map of the Congo basin and adjoining territories : shewing the extent of the Congo Free State, Henry M. Stanley. It was published by Harper & Brothers in 1885. Scale [ca. 1:3,000,000]. This layer is image 2 of 2 total images of the two sheet source map, representing the eastern portion of the map. Covers a portion of Central Africa. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Africa Lambert Conformal Conic projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, cities and other human settlements, shoreline features, and more. Relief shown by hachures and spot heights. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The triggering mechanism and the temporal evolution of large flood events, especially of worst-case scenarios, are not yet fully understood. Consequently, the cumulative losses of extreme floods are unknown. To study the link between weather conditions, discharges and flood losses it is necessary to couple atmospheric, hydrological, hydrodynamic and damage models. The objective of the M-AARE project is to test the potentials and opportunities of a model chain that relates atmospheric conditions to flood losses or risks. The M-AARE model chain is a set of coupled models consisting of four main components: the precipitation module, the hydrology module, the hydrodynamic module, and the damage module. The models are coupled in a cascading framework with harmonized time-steps. First exploratory applications show that the one way coupling of the WRF-PREVAH-BASEMENT models has been achieved and provides promising new insights for a better understanding of key aspects in flood risk analysis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Bibliography: p. [29-33] (2d. group)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Issued as Supplement to Precipitation in Tennessee River basin, March, 1960.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Mode of access: Internet.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

"Report no. 0-243-67S.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

At head of title: U.S. Department of the Interior, Geological Survey and Interstate Commission on the Potomac River Basin.