Amazon River

Ecosystems

In terms of ecosystems and the services they provide the best example is the Nile delta, a rich lush area in terms of ecology in the middle of a desert. This region highlights some of the key ecosystems in the whole of the Nile Basin. 

Ecological Setting

The vast size of the amazon basin, sprawling from the Andes to the Atlantic Ocean, means that there is a high level of variety in the types of habitats that are present. The physical setting of the Amazon basin has led to the development of many ecoregions in this area, with the key ecoregions being that of Rainforest, Seasonal forest, flooded Riparian forest and even savannah. The key habitat in the Amazon basin is the Amazon Rainforest, the most ecologically rich region on the Earth, flooded forest located along the banks of the Amazon river, seasonal forest that is prone to fires along the southeastern border of the basin as well as the Cerrado savanna in the south east of Brazil with its significantly drier climate than the rest of the basin.

Flora

The Amazon basin is home to the most biologically diverse region in the world, the Amazon Rainforest, containing thousands of tree species and over 50,000 identified plant species within the forest. In this region the flora often acts in harmony with each other with the trees in the Amazon rainforest providing a support structure for hundreds of vine and epiphytes species including orchids, mosses and bromeliads, which in turn provide habitats for a large portion of the fauna within the area. 

There is also a vast diversity of flora found within this region with many plants developing defence mechanisms to insure their own survival. This is seen with a large array of plants with aerial roots, such as strangler figs (Ficus spp.). Tropical trees also develop bark that is smooth and thin in nature opposite to the barks seen in temperate trees, this provides much needed protection from flora species that grow on the tree surface as well as reducing the risk of fungal infection. These trees also have leaf structures that allow for the removal of excess water and the prevention of nutrient loss. 

The large number of plant species within the basin also provide benefits on both a local and global scale with the sequestration of carbon aiding in regulating global climate change and the high levels of evapotranspiration sustaining the water cycle of the region. 

As the soil in the amazon is extremely poor in nutrients as a result of the sheer abundance of vegetation in the region as well as the persistent rain in the region leading to harsh conditions for them to grow in. As such in an effort to insure the survival of vegetation from the invertebrate species in the region it is in the plants' best interests to be tasteless, difficult to eat or just plain poisonous. So some plants have developed tough leaves, resins or latex outer coats that make them tough and able to resist many predators. Other plants produce leaves that are nutritionally poor, so insects have to invest a lot of time and effort in eating, which is not a worthwhile strategy for any species.

In terms of localised diversity of vegetation across the Amazon basin it is seen that the nutrient rich floodplain drainage channels provide the best conditions for high biodiversity while a more homogeneous plant cover is found throughout the flood plains themselves (Mertes et al., 1995).

Fauna

The amazon is the most biologically diverse place on the Earth, containing millions of species with most still yet to be identified and described. These species range from both terrestrial and aquatic mammals such as Jaguars, Pink River Dolphins, sloths and spider monkeys. The region is also home to amphibians such as poison dart frogs, 3,000 freshwater fish species including piranha, over 370 different reptiles and more than a thousand bird species such as hummingbirds, toucans and macaws. These numbers are however insignificant in comparison to the number of smaller invertebrate species that have been identified and described which ranges from 96,660 and over 100,000 showing the vast array of life within this region of the Earth. WWF

As such some of the most synonymous species with the amazon basin will be categorised below:

Terrestrial

Mammals 

• Jaguar: The largest cat of the American continent distributed widely across many ecoregions such as the rainforests, flooded swamp areas, grasslands, thorn scrub woodlands and dry deciduous forests with populations decreasing outside of the Amazon rainforest as a result of anthropogenic actions. With an estimate of less than 50,000 breeding individuals in the wild

• Tapir: Located in the lowland tropical and subtropical moist forests. Anthropogenic actions including deforestation, agricultural activity and hunting has led to a reduction in their population.

• Giant Otter: The world's largest otter is found throughout the Amazon basin. The future of this species is however, under threat as a result of river pollution and the loss of suitable habitats.

Reptiles

• Boas: The amazon basin is home to many of the most famous species of snakes in the world, namely the boa constrictor (Boa constrictor), the common tree boa (C. enydris), the emerald tree boa (Corallus caninus), the rainbow boa (Epicrates cenchria) and the green anaconda (Eunectes murinus).

Amphibians

• 427 of the indentified 4,000 amphibian species from around the world are located within the Amazon, including the poison dart frog and the giant cane toad,

Birds

• About 3,800 species are found there – over 1,300 in the Amazon, 28 of which are endemic to the region1. These species include the Harpy eagle (Harpia harpyja), more than 300 species of hummingbirds and Toucans to name a few.

Invertebrates 

• including insects, represent a disproportionately large share of species found in the Amazon - and more are being discovered all the time.

• Some scientists estimate that 30% of the animal biomass of the Amazon Basin is made up of ants1. Ants can easily outweigh in mass all other vertebrates in a parcel of lowland rainforest. In fact, just the total arthropod species richness of the tropical canopy may be as high as 20 million2.

• Leaf-cutter ants : they have the distinction of being the primary consumer of vegetation in the Amazon rainforests, where their actions remove 15% of leaf production

• Termites

• Cockroaches

• Rhinoceros beetles

• Morpho butterflies

Aquatic

Fish

• Of the Amazon fish described so far by science, 40% are catfish and characines2, including the neon tetra (Hyphessobrycon innesi), pearl headstander (Chilodus punctatus), silver hatchetfish (Gasteropelecus levis), bronze corydoras (Corydoras geneus) and the oscar (Astronotus ocellatus).

• Piranha: A fearsome reputation precedes the piranha around the world, but this species is actually much less aggressive than commonly believed. At a respectable length of 35 cm, the red piranha (Sarrasalmus nattereri) is widely distributed and abundant in the Amazon rivers. Only when water levels and food supplies are low is it advisable to stay away from them. Otherwise, they are of no danger to swimmers. Of the 20 piranha species, most are vegetarian.

• Electric eels 

Mammals 

• Pink River dolphins: also known as the boto, the Amazon river dolphin is one of the world's three dolphins that are constrained to freshwater habitat. The species is widely distributed throughout much of the Amazon and Orinoco river basins. Like its relatives elsewhere, the boto's habitat is threatened by river development projects: Hydroelectric and irrigation schemes separate rivers in bodies of waters, which may reduce the species range and its ability to breed.

Reptiles 

• Crocodiles and alligators (Caimans)

Turtles Side-necked turtles: The South American river turtle (Podocnemis expansa), also known as arrau and charapa, is the largest freshwater turtle in South America.