From: The Australian
JEAN-MICHEL Cousteau warns us to expect a dramatic change in the colour of the ocean. We are cruising through sparkling blue Atlantic waters off the coast of Brazil heading towards the mouth of the Amazon River, more than 400km away.
Cousteau, the famed environmentalist and head of the Ocean Futures Society, has partnered with our ship, Regent Seven Seas Mariner, to educate passengers about the Amazon and its effect on the world environment.
He reminds us the Amazon is the planet's largest and most powerful river system, holding more than one-fifth of the fresh water on Earth. It drains an area bigger than the continental US.
Sure enough, the water around us soon begins to look murky, then takes on a brown, muddy hue. It's like sailing through a sea of liquid milk chocolate. There is still no sight of land but we are very much under the influence of the mighty Amazon.
Several hours later we spot a low, green horizon with a wide gap. Clumps of water hyacinth flow in the strong current. We are at the mouth of the Amazon River. Its huge estuary is more than 300km across with a series of silt-formed islands.
It's almost impossible to comprehend the overwhelming scale of the Amazon River and its influence on planet Earth. The drainage basin covers about one-half of South America and gathers water from ninecountries.
From its source in the Andes it runs almost 6500km to the Atlantic Ocean. Its 2000 tributaries add to a prodigious flow of water; 17 of those tributaries are more than 1500km long. Even 1000km upstream, the Amazon occasionally becomes more than 30km wide.
Cousteau comments that the murky cocoa colour of Amazon water is deceptive. In fact, the Amazon is one of the cleanest rivers on the planet, he says. It provides a home for more than 3000 species of fish. On its long journey from the Andes, the river picks up huge amounts of silt and nutrients that it dumps into the Atlantic. These nutrients become part of the Gulf Stream and have a positive effect on marine life in the US, Canada and beyond. There would be no coral reefs in the Caribbean if there was no Amazon, Cousteau states. In fact, the river's influence can be traced all the way to England. It's mind-boggling.
About 40 cruise ships a year head into the Amazon for the four-day 1600km trip to Manaus, a city of 1.6million people positioned where the Rio Negro joins the main river. At that juncture, an extraordinary sight can be witnessed, the Meeting of the Waters. The Rio Negro is black as coffee and when its acidic waters meet the brown milky Amazon they don't immediately blend. Instead they flow side by side for about 10km-15km before the black waters disappear and the chocolate Amazon dominates.
It's a dramatic phenomenon that brings most of the 550 passengers on Seven Seas Mariner out on deck.
To get to Manaus we take our time, steaming slowly against the three to five-knot current and enjoying all the amenities of a luxury cruise ship. The chefs make a point of offering fresh local fish whenever they can and the complementary fine wines are often outstanding South American vintages.
There are no channel markings on the Amazon because the surging water is constantly altering the riverbed. The captain of the Seven Seas Mariner tells us he relies totally on local pilots to guide his route around the shifting sandbars.
At one point we drop anchor in the Rio Tapajos, a minor tributary that still carries more water than the Mississippi, so we can take a small boat into another tributary to fish for piranha and view some of the homes, many of them on stilts for flood protection.
The area seems alive with birds and animals. On one tree we see a large iguana resting on a branch while a three-toed sloth hangs lazily from another limb.
Cousteau tells us there are "more eyes than leaves" along the Amazon, with more than two million known species of insects and countless birds and animals, most of which are well hidden,
Except for occasional villages and isolated homesteads, the low green foliage of tropical trees and vines seems endless.
Cousteau reminds us of the huge problems facing Brazil and the other Amazon countries. Already one-fifth of the rainforest has been destroyed by a slash and burn policy of farmers and foresters. A government-sponsored fertiliser program is having adverse effects because of run-off. Roads through the wilderness are causing environmental problems; devastation is taking place within 5km on either side of those highways.
The Amazon rainforest is absolutely essential to the health of the planet, Cousteau tells us, because of its important role in recycling carbon dioxide. "Every tree we cut should be replaced by a tree," he says. "That isn't happening and the world should be concerned."
As we complete our journey at Manaus (some smaller cruise ships continue another 1600km, ending up well inside Peru) we are struck by the sheer size of this improbable city surrounded by jungle in almost every direction.
Founded by the Portuguese in 1669 as a fortress, Manaus began its huge growth spurt soon after 1839 when Charles Goodyear developed vulcanisation and demand for rubber exploded. Rubber trees, prized for their latex, grew only in the middle of Brazil and the rubber barons of Manaus (thanks, in large part, to slave labour) became very rich. A remarkable reminder of those glory days is the classic Opera House, built in the grand style of the finest theatres in Europe.
After 15 years of work, with most material imported from overseas, the Opera House was completed in 1896 and welcomed Enrico Caruso as one of its early performers. As part of the Regent cruise, we are invited to attend a champagne reception and performance by the Amazon Jazz Ensemble in the restored building. It's a magical evening.
Manaus might have continued as one of the world's wealthiest cities had not a British adventurer smuggled 70,000 rubber tree seeds back to England. Those stolen seeds were sown in Malaysia, causing Brazil to lose its latex monopoly.
That deed and the invention of synthetic rubber by the 1920s meant the end of wealth and decadence in Manaus as the city sank into decay and obscurity.
In the 70s Brazil declared Manaus a duty-free zone and began a program of developing the mineral and agricultural wealth of the area.
This caused a huge growth spurt that stressed the city's infrastructure and the environment. Except for the Opera House and a first-class resort, the city shows little evidence of prosperity.
Cousteau worries about Manaus, the future of the indigenous people, who are largely hidden upstream on the Amazon and tend to be forgotten, and the fragile nature of the Amazon ecosystem.
But, he says, it is important for tourists to visit thisarea and realise how vital the Amazon is to a healthy world.
"People protect what they love," he says. Come and see this river for yourself. You'll be blown away.