Rising in the Peruvian Andes, its main trunk flows eastwards across Brazil. On its way the system drains 1/3 of South America. Eventually, over 4,000 miles from its source, it empties into the Atlantic Ocean. The Amazon transports a billion tonnes of sediment a year, sediment clearly visible at the mixing of the waters where one massive tributary, the Rio Negro, flows into the main river. Its waters are wonderfully rich. To date over 3,000 species of their fish have been described - more than in the whole of the Atlantic Ocean. The Amazon is so large and rich in fish that it can support fresh water dolphins. These botos are huge - two and a half metres long.


它发源于秘鲁境内的安第斯山区，干流穿过巴西，向东流去。它的流域占南美洲面积的1/3。它经过长达6000多公里的旅程，最终注入大西洋。亚马逊河每年挟带的沉积物多达10亿吨，在它与它的一条重要支流内格罗河汇合处，可以清楚地看出这些沉积物。亚马逊河河水养份异常丰富，到今天为止已知的鱼类就达3000多种，比大西洋的鱼类还要多。正因为食物丰富，所以可以供淡水的亚马逊海豚的生活，这种海豚体积很大，最长可达2.5米。