The Floating Forest: Traditional Knowledge and Use of Matupá Vegetation Islands by Riverine Peoples of the Central Amazon

Abstract

Matupás are floating vegetation islands found in floodplain lakes of the central Brazilian Amazon. They form initially from the agglomeration of aquatic vegetation, and through time can accumulate a substrate of organic matter sufficient to grow forest patches of several hectares in area and up to 12 m in height. There is little published information on matupás despite their singular characteristics and importance to local fauna and people. In this study we document the traditional ecological knowledge of riverine populations who live near and interact with matupás. We expected that their knowledge, acquired through long term observations and use in different stages of the matupá life cycle, could help clarify various aspects about the ecology and natural history of these islands that field biologists may not have had the opportunity to observe. Research was carried out in five riverine communities of the Amanã Sustainable Development Reserve (Brazil). Semi-structured interviews were conducted with 45 inhabitants in order to register local understandings of how matupás are formed, biotic/abiotic factors related to their occurrence, the plants and animals that occur on them, their ecological relevance, and local uses. Local people elucidated several little-known aspects about matupá ecology, especially regarding the importance of seasonal dynamics of high/low water for matupás formation and the relevance of these islands for fish populations. Soil from matupás is especially fertile and is frequently gathered for use in vegetable gardens. In some cases, crops are planted directly onto matupás, representing an incipient agricultural experiment that was previously undocumented in the Amazon. Matupás are also considered a strategic habitat for fishing, mainly for arapaima (Arapaima gigas). The systematic study of traditional ecological knowledge proved to be an important tool for understanding this little-known Amazonian landscape.

Indigenous Biosecurity: Māori Responses to Kauri Dieback and Myrtle Rust in Aotearoa New Zealand

“…Many Indigenous communities will therefore have vested interests in the protection and health of forests, the management of which is mainly subject to a legacy of colonial management. International literature on Indigenous communities and conservation is dominated by Western paradigms of conservation but includes examples of researchers working alongside and documenting IK for the purpose of gaining insight into aspects of ecology and natural history (Walter and Hamilton 2014;Camara-Leret et al 2014;de Freitas et al 2015). Studies examining alternative (including Indigenous) approaches to forest conservation document positive impacts of co-managing forests, including minimising the loss of biodiversity (Souto et al 2014;Singh et al 2015).…”

Which variables influence the herbivory amount on Montrichardia spp. (Araceae) in aquatic ecosystems?

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Historical survey of the floating mat model for the origin of Carboniferous coal beds

“…Scholars have called them "floating mats," "floating vegetation islands," or even "floating forests." Botanists, ecologists and geologists are increasing our knowledge of these unusual habitats (Van Duzer 2004, Azza et al 2006, Volkova 2010, de Freitas et al 2015. They are best known within big river systems (e.g., Mississippi, Congo, Nile, Amazon) and within most big coastal freshwater wetlands (e.g., Dismal Swamp, Okefenoke, Everglades).…”