Watersheds Around
The World
Nathan ChenStuart Guan
What is a watershed?• An area
of land that separates water flow to different rivers, basins, or seas
Major Watersheds
North and Central America
South America
Africa
Europe
Asia and Oceania
North and
Central America
• 847,620 sq. km –23%Yukon
• 1,706,388 sq. km –7%Mackenzie
• 239,245 sq. km –0%Thelon
• 248,016 sq. km –7%Fraser
• 1,093,141 sq. km –21%Nelson
• 657,501 sq. km –22%Columbia
• 78,757 sq. km –26%Sacramento
• 3,202,185 sq. km –52%Mississippi
• 703,148 sq. km –43%Colorado
• 1,049,636 sq. km –31%Saint Lawrence
• 78,672 sq. km –14%Susquehanna
• 41,906 sq. km –9%Hudson
• 138,139 sq. km –25%Alabama and Tombigbee
• 137,098 sq. km –81%Brazos
• 607,955 sq. km –52%Rio Grande
• 136,694 sq. km –52%Rio Grande de Santiago
• 79,162 sq. km –16%Yaqui
• 117,095 sq. km - 29%Balsas
• 78,720 sq. km - 37%San Pedro & Usamacinta
Loss of Original Forest Cover
Mississippi Basin• Watershed encompasses 40%
of the U.S.• The Mississippi River is the
largest and longest in terms of discharge (Average 17,330 m3/sec)
• World’s second largest basin• Greatest concern today is “The
Dead Zone”• The problem is nutrient load
generated less oxygen• Possible solutions include
improved farm management and restoration of forest and wetlands removing the excess nutrients.
South America
Magdalena – 10,191
Orinoco – 90,482
Amazon – 273,767
Tocantins – 103,383
Parnaiba – 7,729
Sao Francisco – 8,261
Parana – 8,025
Uruguay – 32,731
Lake Titicaca and Salar de Uyuni – 15,980
Rio Colorado – 3,196
Chubut – 171,362
Water Supply per Person (m3/person/year)
Amazon Basin• Contains 1/5 of the
worlds fresh water• Flows 12 times faster
than Mississippi River• Tropical Rain Forest
supplies over half of the planet’s oxygen
• High point in the watershed (the peak of Yerupajá)[6,635 m]
• Water flows from Pacific Ocean forming the Andes to the Atlantic Ocean
• Outstanding Animal life > 5,000 species
Africa
Ou
ed
Dra
a –
1
0S
en
eg
al –
10
Nig
er
– 31
Lake
Chad
–
11
Nile
– 4
6
Volt
a –
43
Con
go –
15
Ora
ng
e –
10
Jub
ba –
12
Sh
ab
alle
–
29
Og
oou
e –
2
Cu
an
za –
23
Ru
fiji
– 2
1
Zam
bezi
–
18
Oka
van
go –
2
Lim
pop
o –
3
2M
on
goky
–
18
Man
ia –
25
Lake
Turk
ana –
61
Average Population Density (people per sq. km)
Turkana Basin• Northern Kenya and Southern
Ethiopia• Lake Turkana supports the wildlife
and locals• Ineffective drainage becoming an
arid scrubland• Increased evolutionary plant life of
C4 plants• Most sensitive area to temperature
and influx of weather• No transboundary agreement with
the other larger basin nearby stressing Lake Turkana
• Area – the cradle of mankind
Europe
1 – Duero
2 – Kizilirmak
29 – Guadalquivir31 – Kemijoki,
Glomma-Laagen, and Eboro
33 - North Dvina
39 – Seine, Tagus
40 - Lake Ladoga, Garonne
41 – Dalalven
43 – Loire
44 – Oder
47 – Po, Kura-Araks
48 – Ural, Weser
49 – Don
50 - West Dvina, Dnieper
51 - Elbe
57 – Nistru
58 – Rhone
59 – Vistula
60 - Rhine-Maas
88 – Volga
92 - Tigris & Euphrates
Number of Fish Species
Tigris & Euphrates Basin• Monstrous fish weighing as
much as 300 lbs• Economic life dependent on
the rivers and the oil revenues of Iraq
• Lots of desiccated marshland and soil nutrient depletion
• Lack of international agreement Turkey’s dams reduced water flow into Iraq
• Tensions run high on water management
• GAP project (22 dams and 19 hydropower plant) split
Asia and Oceania
0%• Pechora, Yenisey, Lena, Indigirka, Kolyma,
Kapuas, Mahakam, Fly, Sepik
0%-1%• Ob, Tarim,
Amur, Salween
1%-5%• Lake Balkhash, Yalu Jiang, Brahmaputra, Mekong, Irrawaddy,
Red River, Burdekin-Belyando, Dawson, Murray-Darling
5%-10%
• Syr Darya, Amu Darya, Pearl River, Yangtze, Yellow River
10%-15%
• Tapti, Godavari
15%-20% • Mahanadi, Krishna
20%-25%
• Indus, Ganges, Narmada
Percent Irrigated Cropland
Yangtze Basin
• Area = 1.81 million sq. km
• Food staple of China – Rice for 1.3 billion people
• Fertile soil highly favorable to agriculture
• Contributes to > half of China’s crop production (2/3) is rice
• Severe droughts and irregular rainfall result in crop loss
• Solution - modern irrigation projects like the Three Gorges Project
Web Sources• http://www.unep.org/pdf/UNEP_GEAS_JUNE_2013.pdf• http://news.mongabay.com/2006/1024-amazon.html• http://news.nationalgeographic.com/news/2007/06/070619-amazon-river.html• http://global.britannica.com/EBchecked/topic/18722/Amazon-River• http://multimedia.wri.org/watersheds_2003/index.html• http://www.waterencyclopedia.com/Mi-Oc/Mississippi-River-Basin.html• http://www.academia.edu/7277108/Variations_in_water_level_for_Lake_Turkan
a_in_the_past_8500_years_near_Mt._Porr_Kenya_and_the_transition_from_the_African_Humid_Period_to_Holocene_aridity._Quaternary_Science_Reviews_97_84-101
• http://www.futuredirections.org.au/publications/food-and-water-crises/678-water-shortage-crisis-escalating-in-the-tigris-euphrates-basin.html
• http://www.britannica.com/EBchecked/topic/651857/Yangtze-River/48044/People
• http://www.eoearth.org/view/article/173855/