FLUVIAL EROSION RISK ANALYSIS: AN AMAZON STUDY CASE

Análise de risco a erosão fluvial: um estudo de caso na Amazônia

Autores

  • Iris Celeste Nascimento Bandeira Geological Survey of Brazil
  • Raimundo Almir Costa da Conceição Geological Survey of Brazil
  • Milena Marília Nogueira de Andrade Federal Rural University of the Amazon
  • Sheila Gatinho Teixeira Geological Survey of Brazil
  • Dianne Danielle Farias Fonseca Geological Survey of Brazil
  • Joao Batista Marcelo de Lima Geological Survey of Brazil
  • Andressa Macedo Silva de Azambuja Geological Survey of Brazil
  • Aderson Manoel da Silva Gregorio Centro de Instrução Almirante Braz de Aguiar
  • Luciana de Jesus Penha Pamplona Miyagawa Geological Survey of Brazil
  •  Silvio Tadeu Teles da Silva Estácio Nazaré College, Belém-Pará, Brazil
  • Paulo Afonso Pereira Aguiar Geological Survey of Brazil

DOI:

https://doi.org/10.21170/geonorte.2021.V.12.N.39.01.25

Palavras-chave:

Analytic Hierarchy Process - AHP, Hazard, Vulnerability, Pará, Brazil

Resumo

In the Amazon region, there are more than 69.000 people living in areas at risk of fluvial erosion processes. In addition to the large number of people impacted, studies have shown that the erosion patterns identified on the margins of mega rivers in the Amazon region are distinct due to the fact they are related the mass movement leading to great soil displacement known as ‘Terras Caidas’. In this context, this study aims to evaluate quantitatively the degrees of risk in areas subject to fluvial erosion in three communities: Itanduba, São Braz, and Fátima de Urucurituba. The methods include hazard attributes, as well as vulnerability aspects, through the Analytic Hierarchy Process (AHP). A multitemporal analysis were made to validated the marginal erosion a t the studied areas. The results indicated a high risk of fluvial erosion on these areas. The local families lives under high and very high social vulnerability in conditions with little infrastructure and very close to the susceptible erosive riverbank. The riverbank is composed of poorly consolidated sediments, show instability indicators, and are usually associated to drainages with flow rates above 100.000 m3/s. The results and methodology brings an important contribuition to territorial planning of the region.

Biografia do Autor

Raimundo Almir Costa da Conceição, Geological Survey of Brazil

 

 

 

Dianne Danielle Farias Fonseca, Geological Survey of Brazil

 

 

 

Joao Batista Marcelo de Lima, Geological Survey of Brazil

 

 

 

Andressa Macedo Silva de Azambuja, Geological Survey of Brazil

 

 

 

Aderson Manoel da Silva Gregorio, Centro de Instrução Almirante Braz de Aguiar

 

 

 

Luciana de Jesus Penha Pamplona Miyagawa, Geological Survey of Brazil

 

 

 

 Silvio Tadeu Teles da Silva, Estácio Nazaré College, Belém-Pará, Brazil

 

 

 

Paulo Afonso Pereira Aguiar, Geological Survey of Brazil

 

 

 

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2021-06-25

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Nascimento Bandeira, I. C. ., Conceição, R. A. C. da, Nogueira de Andrade, M. M. ., Teixeira, S. G. ., Fonseca, D. D. F. ., Lima, J. B. M. de ., Azambuja, A. M. S. de ., Gregorio, A. M. da S. ., Miyagawa, L. de J. P. P. ., TelesdaSilva, SilvioT., & Aguiar, P. A. P. . (2021). FLUVIAL EROSION RISK ANALYSIS: AN AMAZON STUDY CASE: Análise de risco a erosão fluvial: um estudo de caso na Amazônia. REVISTA GEONORTE, 12(39), 1–25. https://doi.org/10.21170/geonorte.2021.V.12.N.39.01.25

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