Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Drainage Basin shopping experience:
1. Compare - without doubt the biggest advantage that the Drainage Basin offers shoppers today is the ability to compare thousands of Drainage Basin at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Drainage Basin? Wrong! If the Drainage Basin is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Drainage Basin then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Drainage Basin? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Drainage Basin and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Drainage Basin wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Drainage Basin then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Drainage Basin site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Drainage Basin, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Drainage Basin, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
A
drainage basin is a region of land where water from
rain or snow melt drains downhill into a body of water, such as a river, lake, dam,
estuary,
wetland,
sea or ocean. The drainage basin includes both the streams and rivers that convey the water as well as the land surfaces from which water drains into those channels. The drainage basin acts like a funnel - collecting all the water within the area covered by the basin and channeling it into a waterway. Each drainage basin is separated topographically from adjacent basins by a ridge, hill or mountain, which is known as a water divide or a
watershed. Especially in North American usage however,
watershed refers to the drainage basin itself. Other terms that can be used to describe the same concept are
catchment,
catchment area,
catchment basin,
drainage area,
river basin and
water basin.
Major drainage basins of the world
Map
basins that do not drain to the ocean.
Drainage basins of the major oceans and seas of the world. Grey areas are endorheic basins that do not drain to the ocean.
Ocean basins
There are many drainage basins throughout the world. The following is a list of the major ones:The
Atlantic Ocean drains approximately 47% of all land in the world. In North America, it directly drains the
Saint Lawrence River and
Great Lakes basins, the
Eastern Seaboard of the United States, the
Canadian Maritimes, and Newfoundland and Labrador. It also directly drains nearly all of South America (that portion east of the Andes), northern
Europe, and the greatest portion of western Sub-Saharan Africa. The three major Mediterranean sea (oceanography)s of the world also flow to the Atlantic:The basin of the American Mediterranean Sea (the
Caribbean Sea and
Gulf of Mexico) includes all of the United States interior between the Appalachian and Rocky mountains, eastern
Central America, and a small part of northern
South America.The basin of the European
Mediterranean Sea includes much of northeastern Africa (including
Egypt, Libya,
Sudan and the other countries of the Nile basin), southern and eastern Europe,
Turkey, and the coastal areas of Israel, Lebanon, and Syria.The basin of the Arctic Ocean drains most of northern
Rupert's Land and Russia.The Pacific Ocean drains just over 13% of the land in the world. Its basin includes much of
China, southeastern
Russia,
Japan, Korea, most of Indonesia and
Malaysia, the Philippines, all Pacific Islands, the northeast coast of Australia, most of Alaska, the western part of Canada, the United States, Central America, and the South America (the smaller portion west of the Andes).The Indian Ocean drains around 13% of the Earth's land. It drains the eastern coast of Africa, the coasts of the Red Sea and the
Persian Gulf, the
Indian subcontinent,
Burma, and most of Australia.The Southern Ocean drains
Antarctica. Antarctica comprises approximately eight percent of the Earth's land.
Endorheic drainage basins
Endorheic basin are inland basins that do not drain into an ocean; around 18% of all land drains to endorheic lakes or seas. The largest of these consists of much of the interior of
Asia, and drains into the
Caspian Sea and the
Aral Sea. Other basins include the Great Basin in the
United States, much of the
Sahara Desert, the watershed of the
Okavango River (
Kalahari Basin), highlands near the African Great Lakes, the interiors of
Australia and the
Arabian Peninsula, and parts in
Mexico and the Andes.
Importance of drainage basins
As geopolitical boundaries
Drainage basins have been important historically in determining boundaries, particularly in regions where trade by water has been important. For example, the
England crown gave the Hudson's Bay Company a monopoly on the
Indian Trade in the entire
Hudson Bay watershed, an area called Rupert's Land. The company later acquired the North American watershed of the
Arctic Ocean (the North-Western Territory). These lands later became part of
Canada as the Northwest Territories, making up the vast majority of Canada's land area.
Currently the Sistan Basin stretches over the southern parts of
Afghanistan and
Iran.Shangrila Lake in Skardu Pakistan.
Today, bioregional democracy can include agreements of states in a particular drainage basin to defend it. These include the
Great Lakes Commission.
In hydrology
, part of the Mississippi River drainage basin.
In hydrology, the drainage basin is a logical unit of focus for studying the movement of water within the
hydrological cycle, because the majority of water that discharges from the basin outlet originated as Precipitation (meteorology) falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of the discharge of water from a basin may be made by a stream gauge located at the basin's outlet.
Rain gauge data is used to measure total precipitation over a drainage basin, and there are different ways to interpret that data. If the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the watershed is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for the rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The
isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time consuming.
In ecology
drains the largest area of any United States river, much of it agriculture regions. Agricultural runoff and other water pollution that flows to the outlet is the cause of the
dead zone (ecology) in the Gulf of Mexico.
Drainage basins are important elements to consider also in ecology. As water flows over the ground and along rivers it can pick up nutrients, sediment, and
water pollution. Like the water, they get transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body.
Modern usage of artificial fertilizers, containing nitrogen, phosphorus, and potassium, has affected the mouths of watersheds. The minerals will be carried by the watershed to the mouth and accumulate there, disturbing the natural mineral balance.
In resource management
Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In Minnesota, U.S.A., governmental entities that perform this function are called watershed districts. In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called
Conservation Authority. In North America this function is referred to as
watershed management.In
Brazil, the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as territorial division of Brazilian water management.
See also
References
General references
*DeBarry,Paul A. (2004).
Watersheds: Processes, Assessment and Management. John Wiley & Sons.
External links
- A detailed map of watersheds in North America
- Science in Your Watershed, USGS
- Studying Watersheds: A Confluence of Important Ideas
- Water Sustainability Project Sustainable water management through demand management and ecological governance, with the POLIS Project at the University of Victoria
- Map of the Earth's primary drainage basins/watersheds, WRI
- Surf Your Watershed, EPA
-
- Cycleau - A project looking at approaches to managing catchments in North West Europe
- American Water Resources Association
A
drainage basin is a region of land where water from rain or
snow melt drains downhill into a body of water, such as a
river, lake, dam, estuary,
wetland,
sea or ocean. The drainage basin includes both the streams and rivers that convey the water as well as the land surfaces from which water drains into those channels. The drainage basin acts like a funnel - collecting all the water within the area covered by the basin and channeling it into a waterway. Each drainage basin is separated topographically from adjacent basins by a ridge, hill or mountain, which is known as a water divide or a
watershed. Especially in North American usage however,
watershed refers to the drainage basin itself. Other terms that can be used to describe the same concept are
catchment,
catchment area,
catchment basin,
drainage area,
river basin and
water basin.
Major drainage basins of the world
Map
basins that do not drain to the ocean.
Drainage basins of the major oceans and seas of the world. Grey areas are
endorheic basins that do not drain to the ocean.
Ocean basins
There are many drainage basins throughout the world. The following is a list of the major ones:The
Atlantic Ocean drains approximately 47% of all land in the world. In North America, it directly drains the Saint Lawrence River and Great Lakes basins, the
Eastern Seaboard of the United States, the
Canadian Maritimes, and
Newfoundland and Labrador. It also directly drains nearly all of
South America (that portion east of the
Andes), northern
Europe, and the greatest portion of western Sub-Saharan Africa. The three major Mediterranean sea (oceanography)s of the world also flow to the Atlantic:The basin of the American Mediterranean Sea (the Caribbean Sea and
Gulf of Mexico) includes all of the United States interior between the Appalachian and Rocky mountains, eastern
Central America, and a small part of northern
South America.The basin of the European Mediterranean Sea includes much of northeastern Africa (including Egypt, Libya, Sudan and the other countries of the Nile basin), southern and eastern Europe,
Turkey, and the coastal areas of Israel, Lebanon, and Syria.The basin of the Arctic Ocean drains most of northern Rupert's Land and
Russia.The
Pacific Ocean drains just over 13% of the land in the world. Its basin includes much of China, southeastern
Russia, Japan, Korea, most of
Indonesia and Malaysia, the Philippines, all Pacific Islands, the northeast coast of Australia, most of Alaska, the western part of Canada, the United States, Central America, and the
South America (the smaller portion west of the Andes).The Indian Ocean drains around 13% of the Earth's land. It drains the eastern coast of Africa, the coasts of the
Red Sea and the Persian Gulf, the Indian subcontinent,
Burma, and most of
Australia.The
Southern Ocean drains
Antarctica. Antarctica comprises approximately eight percent of the Earth's land.
Endorheic drainage basins
Endorheic basin are inland basins that do not drain into an ocean; around 18% of all land drains to endorheic lakes or seas. The largest of these consists of much of the interior of
Asia, and drains into the
Caspian Sea and the
Aral Sea. Other basins include the Great Basin in the
United States, much of the
Sahara Desert, the watershed of the
Okavango River (Kalahari Basin), highlands near the African Great Lakes, the interiors of Australia and the
Arabian Peninsula, and parts in
Mexico and the Andes.
Importance of drainage basins
As geopolitical boundaries
Drainage basins have been important historically in determining boundaries, particularly in regions where trade by water has been important. For example, the England crown gave the
Hudson's Bay Company a monopoly on the Indian Trade in the entire Hudson Bay watershed, an area called
Rupert's Land. The company later acquired the North American watershed of the
Arctic Ocean (the
North-Western Territory). These lands later became part of
Canada as the
Northwest Territories, making up the vast majority of Canada's land area.
Currently the
Sistan Basin stretches over the southern parts of Afghanistan and
Iran.Shangrila Lake in Skardu
Pakistan.
Today,
bioregional democracy can include agreements of states in a particular drainage basin to defend it. These include the
Great Lakes Commission.
In hydrology
, part of the Mississippi River drainage basin.
In hydrology, the drainage basin is a logical unit of focus for studying the movement of water within the
hydrological cycle, because the majority of water that discharges from the basin outlet originated as Precipitation (meteorology) falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of the discharge of water from a basin may be made by a
stream gauge located at the basin's outlet.
Rain gauge data is used to measure total precipitation over a drainage basin, and there are different ways to interpret that data. If the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the watershed is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for the rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time consuming.
In ecology
drains the largest area of any United States river, much of it agriculture regions. Agricultural runoff and other water pollution that flows to the outlet is the cause of the dead zone (ecology) in the Gulf of Mexico.
Drainage basins are important elements to consider also in
ecology. As water flows over the ground and along rivers it can pick up nutrients, sediment, and
water pollution. Like the water, they get transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body.
Modern usage of artificial fertilizers, containing nitrogen, phosphorus, and potassium, has affected the mouths of watersheds. The minerals will be carried by the watershed to the mouth and accumulate there, disturbing the natural mineral balance.
In resource management
Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In Minnesota, U.S.A., governmental entities that perform this function are called watershed districts. In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called
Conservation Authority. In North America this function is referred to as
watershed management.In
Brazil, the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as territorial division of Brazilian water management.
See also
References
General references
*DeBarry,Paul A. (2004).
Watersheds: Processes, Assessment and Management. John Wiley & Sons.
External links
- A detailed map of watersheds in North America
- Science in Your Watershed, USGS
- Studying Watersheds: A Confluence of Important Ideas
- Water Sustainability Project Sustainable water management through demand management and ecological governance, with the POLIS Project at the University of Victoria
- Map of the Earth's primary drainage basins/watersheds, WRI
- Surf Your Watershed, EPA
-
- Cycleau - A project looking at approaches to managing catchments in North West Europe
- American Water Resources Association
drainage basin
Area of land drained by a river system (a river and its tributaries) ... Tiscali Quicklinks. Please visit our Accessibility Page for a list of the Access Keys you can use to find ...
Drainage basin - Wikipedia, the free encyclopedia
A drainage basin is an extent of land where water from rain or snow melt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea or ocean.
Drainage Basin
Drainage basin, area of land that contributes the water it receives as precipitation (except for losses through evaporation, transpiration from plants, incorporation into the ...
Drainage Basin Characteristics of the Barcelona Region
Barcelona Field Studies Centre offers geography, biology, ecology and environmental field studies programmes throughout the year. Courses can be specifically tailored to the ...
Drainage basin - Encyclopedia of Earth
Geomorphologists and hydrologists often view streams as being part of drainage basins. A drainage basin is the topographic region from which a stream receives runoff ... ...
drainage basin - Hutchinson encyclopedia article about drainage basin
Area of land drained by a river system (a river and its tributaries). It includes the surface run-off in the water cycle, as well as the water table.
drainage basin definition of drainage basin in the Free Online ...
drainage basin: see catchment area catchment area or drainage basin, area drained by a stream or other body of water. The limits of a given catchment area are the heights of land ...
10(aa) The Drainage Basin Concept
Geomorphologists and hydrologists often view streams as being part of drainage basins.
Drainage Basin Simulation Studies
Drainage Basin Simulation Studies. The geomorphology of drainage basins has been studied at the University of Virginia through a series of theoretical and simulations models.
geographyalltheway.com - AS / A2 / IB Geography - The Drainage Basin
Online geography resources, worksheets, revision and lessons for geography teachers and students at KS3, MYP, GCSE, IGCSE, AS, A2 and IB Geography Level ... The Concept of a ...
