There are fears for the people, creatures and plants of the Amazon rainforest which is suffering its worst drought for decades.
The river has dried up in many places, cutting off communities and depriving them of supplies of food and water.
High winds and low rainfall have also left the rainforest in danger from the fires which are started by local farmers to clear their fields.
Officials are having emergency talks to get help to those most in need.
It's likely that military helicopters will be used to deliver food, fuel and medicine to almost 1,000 isolated communities.
The dry spell has already lasted for two months in some areas but there are hopes that it will end soon.
The Amazon is nearly 4,000m long, stretching from Peru to the Atlantic Ocean.