Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater and fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root brak. Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment.
The Tocantins River is a river in Brazil, the central fluvial artery of the country. In the Tupi language, its name means "toucan's beak". It runs from south to north for about 2,450 km. It is not really a branch of the Amazon River, since its waters flow into the Atlantic Ocean alongside those of the Amazon. It flows through four Brazilian states and gives its name to one of Brazil's newest states, formed in 1988 from what was until then the northern portion of Goiás.
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently for years or decades or seasonally for a shorter periods. Flooding results in oxygen-free anoxic processes prevailing, especially in the soils. The primary factor that distinguishes wetlands from terrestrial land forms or water bodies is the characteristic vegetation of aquatic plants, adapted to the unique anoxic hydric soils. Wetlands are considered among the most biologically diverse of all ecosystems, serving as home to a wide range of plant and animal species. Methods for assessing wetland functions, wetland ecological health, and general wetland condition have been developed for many regions of the world. These methods have contributed to wetland conservation partly by raising public awareness of the functions some wetlands provide. Constructed wetlands are designed and built to treat municipal and industrial wastewater as well as to divert stormwater runoff. Constructed wetlands may also play a role in water-sensitive urban design.
A piranha or piraña is any of a number of freshwater fish species in the family Serrasalmidae, or the subfamily Serrasalminae within the tetra family, Characidae in order Characiformes. These fish inhabit South American rivers, floodplains, lakes and reservoirs. Although often described as extremely predatory and mainly feeding on fish, their dietary habits vary extensively, and they will also take plant material, leading to their classification as omnivorous.
A frugivore is an animal that thrives mostly on raw fruits or succulent fruit-like produce of plants such as roots, shoots, nuts and seeds. Approximately 20% of mammalian herbivores eat fruit. Frugivores are highly dependent on the abundance and nutritional composition of fruits. Frugivores can benefit or hinder fruit-producing plants by either dispersing or destroying their seeds through digestion. When both the fruit-producing plant and the frugivore benefit by fruit-eating behavior the interaction is a form of mutualism.
The white-cheeked spider monkey is a species of spider monkey, a type of New World monkey, endemic to Brazil. It moves around the forest canopy in small family groups of two to four, part of larger groups of a few dozen animals. This monkey feeds on leaves, flowers, fruits, bark, honey and small insects, and it is an important means of seed dispersal for forest trees. Females give birth after a 230-day gestation period. The population of this monkey is decreasing as its forest habitat is lost to soybean production, deforestation and road construction. It is also regarded as a delicacy and hunted for food. For these reasons, the International Union for Conservation of Nature has assessed the animal's conservation status as being "endangered".
The tambaqui is a large species of freshwater fish in the family Serrasalmidae. It is native to tropical South America, but kept in aquaculture and introduced elsewhere. It is also known by the names black pacu, black-finned pacu, giant pacu, cachama, gamitana, and sometimes as pacu.
Marine larval ecology is the study of the factors influencing dispersing larvae, which many marine invertebrates and fishes have. Marine animals with a larva typically release many larvae into the water column, where the larvae develop before metamorphosing into adults.
Piaractus brachypomus, the pirapitinga, is a large species of pacu, a close relative of piranhas and silver dollars, in the serrasalmid family. It is native to the Amazon basin in tropical South America, but it formerly included populations in the Orinoco, which was described in 2019 as a separate species, P. orinoquensis. Additionally, P. brachypomus is widely farmed and has been introduced to other regions. In South Florida they are invasive in rivers, canals or lakes.
Defaunation is the global, local, or functional extinction of animal populations or species from ecological communities. The growth of the human population, combined with advances in harvesting technologies, has led to more intense and efficient exploitation of the environment. This has resulted in the depletion of large vertebrates from ecological communities, creating what has been termed "empty forest". Defaunation differs from extinction; it includes both the disappearance of species and declines in abundance. Defaunation effects were first implied at the Symposium of Plant-Animal Interactions at the University of Campinas, Brazil in 1988 in the context of Neotropical forests. Since then, the term has gained broader usage in conservation biology as a global phenomenon.
The granulated catfish is a species of thorny catfish found in the Paraná and Amazon basin as well as the coastal drainages of Suriname and Guyana. This species is commercially caught for human consumption as well as being displayed in public aquaria.
Lindera melissifolia, common name pondberry or southern spicebush, is a stoloniferous, deciduous, aromatic shrub in the laurel family. This endangered species is native to the southeastern United States, and its demise is associated with habitat loss from extensive drainage of wetlands for agriculture and forestry. Restoration efforts are currently being conducted.
Igapó is a word used in Brazil for blackwater-flooded forests in the Amazon biome. These forests and similar swamp forests are seasonally inundated with freshwater. They typically occur along the lower reaches of rivers and around freshwater lakes. Freshwater swamp forests are found in a range of climate zones, from boreal through temperate and subtropical to tropical. In the Amazon Basin of Brazil, a seasonally whitewater-flooded forest is known as a várzea, which is similar to igapó in many regards; the key difference between the two habitats is in the type of water that floods the forest.
Cantão is a tropical forest ecosystem located in the central Araguaia river basin, the southeastern edge of the Amazon biome, in the Brazilian state of Tocantins. It is one of the biologically richest areas of the eastern Amazon, with over 700 species of birds, nearly 300 species of fish, and large populations of endangered species such as the giant otter and the black cayman. About 90% of the Cantão ecosystem is protected within Cantão State Park.
Pentaclethra macroloba is a large and common leguminous tree in the genus Pentaclethra native to the wet tropical areas of the northern Neotropics, which can form monocultural stands in some seasonally flooded habitats. It has giant, bipinnate leaves shaped like feathers. It uses seed dispersal by water to establish itself in new areas, having floating seeds that are left behind after the waters recede after floods or tides. It has hard timber which is not very resistant to rot in the tropics, but it can be treated, has a pretty pink-red colour when dry, and has a number of uses. Oil used in cosmetics is extracted from the large seeds. In the northern Amazon region the bark is used in herbal medicine as an antivenom, and in the Guianas the bark has been used as a fish poison. Despite their toxicity, the seeds are eaten by variegated squirrels, parrots and macaws, and serve as the nurseries of the larvae of the moth Carmenta surinamensis.
A várzea forest is a seasonal floodplain forest inundated by whitewater rivers that occurs in the Amazon biome. Until the late 1970s, the definition was less clear and várzea was often used for all periodically flooded Amazonian forests.
Mylossoma duriventre, the silver mylossoma, is a species of freshwater serrasalmid fish endemic to tropical and subtropical South America. It grows to a maximum length of about 25 cm (10 in) and a weight of 1 kg (2.2 lb). It is the subject of a local fishery, being known as 'pacu' in Brazil and 'palometa' in Venezuela.
The Marajó várzea (NT0138) is an ecoregion of seasonally and tidally flooded várzea forest in the Amazon biome. It covers a region of sedimentary islands and floodplains at the mouth of the Amazon that is flooded twice daily as the ocean tides push the river waters onto the land. The flooded forests provide food for a wide variety of fruit-eating fish, aquatic mammals, birds and other fauna. It has no protected areas and is threatened by cattle and water-buffalo ranching, logging and fruit plantations.
The Monte Alegre várzea (NT0141) is an ecoregion of seasonally flooded várzea forest along the Amazon River in the Amazon biome.
Hevea spruceana is a species of rubber tree in the genus Hevea, belonging to the family Euphorbiaceae. It is native to the rainforests of northern Brazil and Guyana. It is named in honour of the English botanist Richard Spruce who spent the years 1849 to 1864 exploring the Amazon basin and sending botanical specimens back to Europe.
