Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Processo FAPESP: 2013/04284-3 Processo FAPESP: 2014/02298-0 Two reaches of Aguapeí River, a left-bank tributary of the Paraná River in western São Paulo state, Brazil, were studied with the objective of assessing the role of bend curvatur...
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Online Access: | http://hdl.handle.net/11449/175890 https://doi.org/10.1002/esp.4343 |
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ftunivespir:oai:repositorio.unesp.br:11449/175890 2023-07-02T03:33:49+02:00 Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil Suizu, Tainá Medeiros Nanson, Gerald C. Universidade Estadual Paulista (UNESP) 2018-06-30 1636-1647 http://hdl.handle.net/11449/175890 https://doi.org/10.1002/esp.4343 eng eng Earth Surface Processes and Landforms 1,493 http://dx.doi.org/10.1002/esp.4343 Earth Surface Processes and Landforms, v. 43, n. 8, p. 1636-1647, 2018. 1096-9837 0197-9337 http://hdl.handle.net/11449/175890 doi:10.1002/esp.4343 2-s2.0-85042106159 closedAccess Aguapeí River channel migration channel planform-change ENSO climate-change freely-meandering rivers info:eu-repo/semantics/article 2018 ftunivespir https://doi.org/10.1002/esp.4343 2023-06-12T17:08:38Z Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Processo FAPESP: 2013/04284-3 Processo FAPESP: 2014/02298-0 Two reaches of Aguapeí River, a left-bank tributary of the Paraná River in western São Paulo state, Brazil, were studied with the objective of assessing the role of bend curvature on channel migration in this wet-tropical system and examining if land-use changes or ENSO (El Niño Southern Oscillation) driven climate anomalies over nearly half a century have changed migration behaviour and planform geometry. Meander-bend migration rates and morphometric parameters including meander-bend curvature, sinuosity, meander wavelength and channel width, were measured and the frequency of bend cutoffs was analysed in order to determine the rate of change of channel adjustment over a 48 year period to 2010. Results show that maximum average channel migration rates occur in bends with curvatures of about 2–3 rc/w, similar to other previously studied temperate and subarctic freely meandering rivers although not as pronounced and with a tendency to favour tighter curvature. From 1962 to 2010 the Aguapeí River has undergone a significant reduction in sinuosity, a shift from tightly curving to more open bends, an overall decline in channel migration rates, an associated decrease in the frequency of neck-cutoffs and an overall increase in channel width. As the majority of the drainage basin (96%) was already deforested in 1962, channel form and process changes were, unlike an interpretation for an adjacent river system, not attributed to altered land-use but rather to a sharp ENSO-driven increase in the magnitude of peak flow-discharges of some 32% since 1972. In summary, this research revealed that recent climate and associated flow regime changes are having a pronounced effect on river channel behaviour in the Aguapeí River investigated here. Copyright © 2018 John Wiley & Sons, Ltd. Article in Journal/Newspaper Subarctic Universidade Estadual Paulista São Paulo: Repositório Institucional UNESP Earth Surface Processes and Landforms 43 8 1636 1647 |
institution |
Open Polar |
collection |
Universidade Estadual Paulista São Paulo: Repositório Institucional UNESP |
op_collection_id |
ftunivespir |
language |
English |
topic |
Aguapeí River channel migration channel planform-change ENSO climate-change freely-meandering rivers |
spellingShingle |
Aguapeí River channel migration channel planform-change ENSO climate-change freely-meandering rivers Suizu, Tainá Medeiros Nanson, Gerald C. Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
topic_facet |
Aguapeí River channel migration channel planform-change ENSO climate-change freely-meandering rivers |
description |
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Processo FAPESP: 2013/04284-3 Processo FAPESP: 2014/02298-0 Two reaches of Aguapeí River, a left-bank tributary of the Paraná River in western São Paulo state, Brazil, were studied with the objective of assessing the role of bend curvature on channel migration in this wet-tropical system and examining if land-use changes or ENSO (El Niño Southern Oscillation) driven climate anomalies over nearly half a century have changed migration behaviour and planform geometry. Meander-bend migration rates and morphometric parameters including meander-bend curvature, sinuosity, meander wavelength and channel width, were measured and the frequency of bend cutoffs was analysed in order to determine the rate of change of channel adjustment over a 48 year period to 2010. Results show that maximum average channel migration rates occur in bends with curvatures of about 2–3 rc/w, similar to other previously studied temperate and subarctic freely meandering rivers although not as pronounced and with a tendency to favour tighter curvature. From 1962 to 2010 the Aguapeí River has undergone a significant reduction in sinuosity, a shift from tightly curving to more open bends, an overall decline in channel migration rates, an associated decrease in the frequency of neck-cutoffs and an overall increase in channel width. As the majority of the drainage basin (96%) was already deforested in 1962, channel form and process changes were, unlike an interpretation for an adjacent river system, not attributed to altered land-use but rather to a sharp ENSO-driven increase in the magnitude of peak flow-discharges of some 32% since 1972. In summary, this research revealed that recent climate and associated flow regime changes are having a pronounced effect on river channel behaviour in the Aguapeí River investigated here. Copyright © 2018 John Wiley & Sons, Ltd. |
author2 |
Universidade Estadual Paulista (UNESP) |
format |
Article in Journal/Newspaper |
author |
Suizu, Tainá Medeiros Nanson, Gerald C. |
author_facet |
Suizu, Tainá Medeiros Nanson, Gerald C. |
author_sort |
Suizu, Tainá Medeiros |
title |
Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
title_short |
Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
title_full |
Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
title_fullStr |
Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
title_full_unstemmed |
Temporal and spatial adjustments of channel migration and planform geometry: responses to ENSO driven climate anomalies on the tropical freely-meandering Aguapeí River, São Paulo, Brazil |
title_sort |
temporal and spatial adjustments of channel migration and planform geometry: responses to enso driven climate anomalies on the tropical freely-meandering aguapeí river, são paulo, brazil |
publishDate |
2018 |
url |
http://hdl.handle.net/11449/175890 https://doi.org/10.1002/esp.4343 |
genre |
Subarctic |
genre_facet |
Subarctic |
op_relation |
Earth Surface Processes and Landforms 1,493 http://dx.doi.org/10.1002/esp.4343 Earth Surface Processes and Landforms, v. 43, n. 8, p. 1636-1647, 2018. 1096-9837 0197-9337 http://hdl.handle.net/11449/175890 doi:10.1002/esp.4343 2-s2.0-85042106159 |
op_rights |
closedAccess |
op_doi |
https://doi.org/10.1002/esp.4343 |
container_title |
Earth Surface Processes and Landforms |
container_volume |
43 |
container_issue |
8 |
container_start_page |
1636 |
op_container_end_page |
1647 |
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1770273912834228224 |