This being the
first day on the river and with no port call today, it seems like an
opportunity to present some facts about the Amazon. There is so much data available online and
elsewhere that the following is nothing more than a highly abbreviated overview.
At the end of this canned
summary there is a bit about our first day on the river.
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Amazon River
The Amazon River is generally
regarded as the second longest river in the world and is by far the largest by water flow with an average
discharge of about 7,381,000
cubic feet per second, greater than the next seven largest rivers
combined. The Amazon, which has the largest drainage basin in the world, about 2,720,000 square miles, accounts for
approximately one-fifth of the world's total river flow. The river would have
the biggest drainage
basin in the world even just counting Brazil, which it enters
with only one-fifth of the volume that will finally be discharged into the
Atlantic.
Drainage area
The Amazon Basin, the largest in the world, covers about
40% of South America. It drains from
west to east, from Iquitos in Peru, across
Brazil to the Atlantic. It gathers its waters from 5
degrees north latitude to 20
degrees south latitude. Its most remote sources are found on the inter-Andean plateau, just a
short distance from the Pacific Ocean. The locals often
refer to it as "El Jefe Negro", referring to an ancient god of
fertility.
The Amazon River and its tributaries are characterized by
extensive forested areas that become flooded every rainy season. Every year the
river rises more than 30 feet, flooding the surrounding forests, known as várzea ("flooded
forests"). The Amazon's flooded forests are the most extensive example of
this habitat type in the world. In an average dry season, 42,000 square miles
of land are water-covered, while in the wet season, the flooded area
of the Amazon Basin rises to 140,000 square miles.
The quantity of water released by the Amazon to the
Atlantic Ocean is enormous. The Amazon
is responsible for about 20% of the Earth's fresh water entering the
ocean. The river pushes
a vast plume of fresh water into the ocean. The plume is about 250 miles
long and between 62 and 124 miles wide. The fresh water, being lighter,
flows on top of the seawater, diluting the salinity and altering the
color of the ocean surface. For centuries ships have reported fresh water near
the Amazon's mouth yet well out of sight of land in what otherwise seemed to be
the open ocean.
Origins
The Amazon River has a series of major river systems in Colombia, Ecuador and Peru, some of which
flow into the Marañón and Ucayali,
others directly into the Amazon proper.
The most distant source of the Amazon was established as
a glacial stream on a snowcapped 18,363 foot peak called Nevado Mismi in the Peruvian Andes.
The river systems and flood plains in Brazil, Peru,
Ecuador, Colombia and Venezuela, whose waters drain into the Solimões
and its tributaries, are called the "Upper Amazon". The Amazon River
proper runs mostly through Brazil and Peru. It is part of the border between
Colombia and Perú, and it has tributaries reaching into Venezuela, Colombia,
Ecuador, and Bolivia.
Fauna
More than one-third of all known species in the world
live in the Amazon
Rainforest, a giant tropical
forest and river basin. It is the richest tropical forest in the world in terms
of biodiversity. There are over
2,100 species of fish currently recognized in the Amazon Basin, with more being
discovered every year.
Mammals
Along with the Orinoco, the Amazon is one of the main
habitats of the boto, also known as
the Amazon
River dolphin. It is the
largest species of river
dolphin. The color of its
skin changes with age. It varies from gray when it is young, to pink and white
as it matures. The boto is the subject of a legend in Brazil about a dolphin that turns into a
man and seduces maidens by the riverside.
The Amazonian manatee also known as
"seacow" is found in the northern Amazon River Basin and its
tributaries.
The Amazon and its tributaries are the main habitat of
the giant
otter. It is a member of the weasel family and is the
largest of its kind. Because of habitat destruction and hunting its population
has dramatically decreased.
Reptiles
The anaconda is found in
shallow waters in the Amazon Basin. One of the world's largest species of
snake, the anaconda spends most of its time in the water, with just its
nostrils above the surface. In addition to the thousands of species of fish,
the river supports crabs, algae, and turtles. The caiman, which is related
to alligators and other crocodilians, also inhabits the Amazon.
Fish
Present in large numbers is the notorious piranha, an omnivorous
fish which congregates in large schools and may attack livestock and even
humans. There are approximately 30 to 60 species of piranha. However, only a
few of its species are known to attack humans. Sharks, electric eels, sharks
and many other species are also present.
History
During what many archaeologists call the formative
period, Amazonian societies were deeply involved in the emergence of South
America's highland agrarian systems, and
possibly contributed directly to the social and religious fabric constitutive
of the Andean civilizational
orders.
By the turn of the 20th century, the exports of the
Amazon Basin were India-rubber, cacao beans, Brazil nuts and a few other
products of minor importance, such as pelts and exotic forest
produce (resins, barks, woven hammocks, prized bird feathers, live animals)
and extracted goods such as lumber and gold.
[excerpt
from a much longer entry in Wikipedia]
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During the
night we entered the river, going a short distance up it to Macapa where we
anchored at 0700 to await the local authorities and two pilots. The ship having been cleared to proceed
upriver, the anchor was weighed at 0930 and MAASDAM got underway for Satorem
with an ETA there of about 0800 tomorrow.
We pass the
occasional ship headed downriver.
Periodically we see a house on the river bank. We have waved at a few motorized dugouts and
slightly larger boats that have set out from shore apparently just to watch us
go by.
The
constants haves been the muddy water of the Amazon and the density of the
vegetation right down to the shoreline. The water is uniformly a light brown
color – the variations in the pictures are caused by cloud shadows. The transition from water to jungle is
measured in inches.
The third
constant has been the heat and humidity.
Towering cumulus clouds are harbingers of heavy, localized showers that
swept by like thick fog. We have grazed
one of these but have yet to sustain our first direct hit.
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