Recent geomorphological evolution of channel bar in Magdalena River (Colombia) due to natural and anthropogenic interferences, 2022
The growing establishment of port structures in estuarine regions has resulted in alternated sedi... more The growing establishment of port structures in estuarine regions has resulted in alternated sedimentation patterns and new geoforms. The primary purpose of this study is to understand the recent formation and geomorphological evolution of the fluvial bar in the final portion of the Magdalena River. The geomorphological evolution analysis was made possible using Geographic Information Systems tools, satellite images, and bathymetric data. The studied bar formed and stabilized through anthropic and natural factors such as port structures (obstacles to sediment transport), channel morphology, and natural-and anthropic-caused variation to the sediment supply. The lateral bar formation, adjacent to port structures, began in 2017 with surface runoff accumulating and anchored on the riverbank since 2018. At present, the bar covers 45% of the original river width, and an approximate sediment volume worth 4,000,000 m 3 has accumulated. Changes in the navigable channel result in slope modification from 2.02 • to 5.36 •. The construction of port structures, i.e. new pile bridges, changes the natural sediment flow, because they are obstacles, trapping sediments downstream. This period coincides with the end of a weak El Niño cycle, subsequent to a La Nina period also of low intensity, with reduced precipitation rates resulting in a decrease in flow, and therefore contributing to an increase in sedimentation. The observations suggest that it is crucial to understand the channel bars' morphology and origin to avoid possible economic and social impacts due to the disruptions in navigation.
Large Woody Debris (LWD) accumulation serves essential ecological functions and benefits society’... more Large Woody Debris (LWD) accumulation serves essential ecological functions and benefits society’s coastal ecosystems (e.g., beaches). Thus far, the ecosystem services perspective has paid little attention to LWD. Therefore, we aim to contrast social perceptions on LWD and its ecological significance in Puerto Velero beach, Caribbean, Colombia. In consequence, the contribution of LWD to the conformation and creation of Puerto Velero beach was analyzed, as well as how beachgoers perceive the importance of LWD and if they were willing to pay to remove LWD in this beach. To achieve this, a quantitative convergent approach was then proposed using GIS analysis and remote sensing to understand the contributions of LWD to the Puerto Velero beach ecosystem; and in addition, a survey was performed to determine how beachgoers perceived LWD and how they valued the phenomenon. Results indicate that LWD contributed to beach maintenance; nevertheless, most people neglected LWD values because of i...
Beach landscape Dataset of Fernando de Noronha Island (Brazil), using a checklist with 26 physica... more Beach landscape Dataset of Fernando de Noronha Island (Brazil), using a checklist with 26 physical and human parameters. Fernando de Noronha beaches were divided into sectors according to the landscape diversity. In total, 19 sectors were evaluated based on observations done during walks in the area, observations from viewpoints, with remote data. The evaluations were performed during fieldwork from 2014 (summer) and 2016 (spring). The landscape quality evaluation of Fernando de Noronha was performed using the Coastal Scenery Evaluation System. This method converts qualitative-quantitative data in quantitative data by estimating weights for 26 parameters (18 physical parameters – P - and 8 human-related parameters – H). The main parameters that define the landscape quality are classified from 1 (absence/bad quality) to 5 (presence/excellent quality). A mathematical model based on fuzzy logic was utilized to integrate the parameters weights in a special system for the scenarios classifications resulting in a value named D. The D-value is the indicator of the attractiveness of the evaluated place. The beaches are divided into classes ranging from 1 (extremely attractive natural site) to 5 (unattractive urban areas).
Colombia has approximately 379,954 hectares of mangrove forests distributed along the Pacific Oce... more Colombia has approximately 379,954 hectares of mangrove forests distributed along the Pacific Ocean and the Caribbean Sea coasts. Such forests are experiencing the highest annual rate of loss recorded in South America and, in the last three decades, approximately 40,000 hectares have been greatly affected by natural and, especially, human impacts. This study determined, by the use of Landsat multispectral satellite images, the evolution of three mangrove forests located in the Colombian Caribbean Sea: Malloquín, Totumo, and La Virgen swamps. Mangrove forest at Mallorquín Swamp recorded a loss of 15 ha in the period of 1985–2018, associated with alterations in forest hydrology, illegal logging, urban growth, and coastal erosion. Totumo Swamp lost 301 ha in the period 1985–2018 associated with changes in hydrological conditions, illegal logging, and increased agricultural and livestock uses. La Virgen Swamp presented a loss of 31 ha in the period of 2013–2018 that was linked to the co...
A ocupação sem planejamento da Zona Costeira tem promovido a substituição do ambiente natural ori... more A ocupação sem planejamento da Zona Costeira tem promovido a substituição do ambiente natural original pelo ambiente antrópico, cuja implantação apresenta condições que desequilibram a Diversidade Ambiental (naturezas abiótica e biótica) e prejudicam o próprio ambiente antrópico. Essa problemática tende a continuar e se agravar em municípios pequenos, como é o caso de Jaguaruna/SC. O presente trabalho apresenta o método de estruturação das primeiras etapas de um planejamento estratégico costeiro desenvolvido no balneário Camacho/Jaguaruna por meio de ações e cenários de manejo baseados no mapeamento de condições de conflito, na aplicação do Índice de Criticidade Legal-Ambiental (ICLA), no paradigma da Geodiversidade e na dinâmica sedimentar. Em ambiente de Sistema de Informações Geográficas, foi realizada a regionalização paisagística da Diversidade Ambiental pelo cruzamento de informações das naturezas abiótica e biótica. Após a identificação e a hierarquização das principais condi...
Recent geomorphological evolution of channel bar in Magdalena River (Colombia) due to natural and anthropogenic interferences, 2022
The growing establishment of port structures in estuarine regions has resulted in alternated sedi... more The growing establishment of port structures in estuarine regions has resulted in alternated sedimentation patterns and new geoforms. The primary purpose of this study is to understand the recent formation and geomorphological evolution of the fluvial bar in the final portion of the Magdalena River. The geomorphological evolution analysis was made possible using Geographic Information Systems tools, satellite images, and bathymetric data. The studied bar formed and stabilized through anthropic and natural factors such as port structures (obstacles to sediment transport), channel morphology, and natural-and anthropic-caused variation to the sediment supply. The lateral bar formation, adjacent to port structures, began in 2017 with surface runoff accumulating and anchored on the riverbank since 2018. At present, the bar covers 45% of the original river width, and an approximate sediment volume worth 4,000,000 m 3 has accumulated. Changes in the navigable channel result in slope modification from 2.02 • to 5.36 •. The construction of port structures, i.e. new pile bridges, changes the natural sediment flow, because they are obstacles, trapping sediments downstream. This period coincides with the end of a weak El Niño cycle, subsequent to a La Nina period also of low intensity, with reduced precipitation rates resulting in a decrease in flow, and therefore contributing to an increase in sedimentation. The observations suggest that it is crucial to understand the channel bars' morphology and origin to avoid possible economic and social impacts due to the disruptions in navigation.
Large Woody Debris (LWD) accumulation serves essential ecological functions and benefits society’... more Large Woody Debris (LWD) accumulation serves essential ecological functions and benefits society’s coastal ecosystems (e.g., beaches). Thus far, the ecosystem services perspective has paid little attention to LWD. Therefore, we aim to contrast social perceptions on LWD and its ecological significance in Puerto Velero beach, Caribbean, Colombia. In consequence, the contribution of LWD to the conformation and creation of Puerto Velero beach was analyzed, as well as how beachgoers perceive the importance of LWD and if they were willing to pay to remove LWD in this beach. To achieve this, a quantitative convergent approach was then proposed using GIS analysis and remote sensing to understand the contributions of LWD to the Puerto Velero beach ecosystem; and in addition, a survey was performed to determine how beachgoers perceived LWD and how they valued the phenomenon. Results indicate that LWD contributed to beach maintenance; nevertheless, most people neglected LWD values because of i...
Beach landscape Dataset of Fernando de Noronha Island (Brazil), using a checklist with 26 physica... more Beach landscape Dataset of Fernando de Noronha Island (Brazil), using a checklist with 26 physical and human parameters. Fernando de Noronha beaches were divided into sectors according to the landscape diversity. In total, 19 sectors were evaluated based on observations done during walks in the area, observations from viewpoints, with remote data. The evaluations were performed during fieldwork from 2014 (summer) and 2016 (spring). The landscape quality evaluation of Fernando de Noronha was performed using the Coastal Scenery Evaluation System. This method converts qualitative-quantitative data in quantitative data by estimating weights for 26 parameters (18 physical parameters – P - and 8 human-related parameters – H). The main parameters that define the landscape quality are classified from 1 (absence/bad quality) to 5 (presence/excellent quality). A mathematical model based on fuzzy logic was utilized to integrate the parameters weights in a special system for the scenarios classifications resulting in a value named D. The D-value is the indicator of the attractiveness of the evaluated place. The beaches are divided into classes ranging from 1 (extremely attractive natural site) to 5 (unattractive urban areas).
Colombia has approximately 379,954 hectares of mangrove forests distributed along the Pacific Oce... more Colombia has approximately 379,954 hectares of mangrove forests distributed along the Pacific Ocean and the Caribbean Sea coasts. Such forests are experiencing the highest annual rate of loss recorded in South America and, in the last three decades, approximately 40,000 hectares have been greatly affected by natural and, especially, human impacts. This study determined, by the use of Landsat multispectral satellite images, the evolution of three mangrove forests located in the Colombian Caribbean Sea: Malloquín, Totumo, and La Virgen swamps. Mangrove forest at Mallorquín Swamp recorded a loss of 15 ha in the period of 1985–2018, associated with alterations in forest hydrology, illegal logging, urban growth, and coastal erosion. Totumo Swamp lost 301 ha in the period 1985–2018 associated with changes in hydrological conditions, illegal logging, and increased agricultural and livestock uses. La Virgen Swamp presented a loss of 31 ha in the period of 2013–2018 that was linked to the co...
A ocupação sem planejamento da Zona Costeira tem promovido a substituição do ambiente natural ori... more A ocupação sem planejamento da Zona Costeira tem promovido a substituição do ambiente natural original pelo ambiente antrópico, cuja implantação apresenta condições que desequilibram a Diversidade Ambiental (naturezas abiótica e biótica) e prejudicam o próprio ambiente antrópico. Essa problemática tende a continuar e se agravar em municípios pequenos, como é o caso de Jaguaruna/SC. O presente trabalho apresenta o método de estruturação das primeiras etapas de um planejamento estratégico costeiro desenvolvido no balneário Camacho/Jaguaruna por meio de ações e cenários de manejo baseados no mapeamento de condições de conflito, na aplicação do Índice de Criticidade Legal-Ambiental (ICLA), no paradigma da Geodiversidade e na dinâmica sedimentar. Em ambiente de Sistema de Informações Geográficas, foi realizada a regionalização paisagística da Diversidade Ambiental pelo cruzamento de informações das naturezas abiótica e biótica. Após a identificação e a hierarquização das principais condi...
Dune Management Plans are useful tools to integrate coastal development,
dune conservation and ev... more Dune Management Plans are useful tools to integrate coastal development, dune conservation and even dune restoration. The environmental legislation of Rio Grande do Sul (South of Brasil) establishes a Permanent Preservation Area of 60-m minimum width that should be protected in the coastal dune systems. This study shows the implementation of a coastal management plan in Osório Municipality (N of Rio Grande do Sul) for the restoration of the foredune. The analysis of previous evolution (1997–2010) of the dune field showed widths lower than the legal requirement and decreasing in the last years. Then, a dune restoration plan was designed and implemented in 2011. The measures included the planned retreat of the road located back the foredune, channelization of the northern whashout’s mouth with a structure under the foredune, installation of sand fences and control of the pedestrian accesses to the beach by both a pathway and a footbridge. Finally, efficiency of the management plan was assessed by monitoring (2011–2016) the foredune evolution, which permitted to conclude a satisfactory result. Only the foredune sector close to the washout’ mouth did not achieve the expected minimum width, but it can be considered acceptable considering its higher sedimentary dynamics, the inherent difficulties of these structures and the short monitoring period from the implementation of the plan.
The Orla Project is a tool of the Brazilian Coastal Management resultant
of joint action between ... more The Orla Project is a tool of the Brazilian Coastal Management resultant of joint action between the Environment Ministry and the Planning Ministry. This project articulates the three spheres of the government (federal, state, and municipal) and society. Its actions seek the management of the coastal spaces, approaching the environmental and heritage politics. The construction of a Plan for the Integrated Management of the Coastline occurs through workshops with the development of methodologies of diagnosis construction, classification and formulation of scenarios. The classification of the coastline integrates the strategic planning, which will subsidize the decision making process to reach the desired scenarios. Araranguá municipality started its workshops in October 2014, with lectures and discussions between technicians from the federal and state governments, and coordination by the municipal government. During the project period, a field day and more than 40 workshops were developed, which had the participation of the community and public managers. As a result of the workshops, the coastline was sectored by its landscape, typology (exposed, semi-exposed, and sheltered), and levels of occupation in five sectors (S1 to S5). The project identified 40 problems in the area, some recurrent in all sectors and a few specific of some places. In order to solve these problems, 80 actions and measures with different priorities were defined. From the workshops of the Orla Project, it was possible to identify the need to create rules for the use of Araranguá coastline, thus enabling its conservation and helping its sustainable development.
The Itapeva dunefield is an active aeolian transgressive dunefield system and an important conser... more The Itapeva dunefield is an active aeolian transgressive dunefield system and an important conservation area (PEVA State Park) in Torres-RS, Brazil. It is cataloged as a geosite and contains geoforms of scientific value for studying the sedimentary environments and paleoclimates of southern Brazil. It stands out for its esthetic, cultural, and recreational value for the development of tourism. However, the use and occupation of its surroundings developed rapidly, and the environmental problems associated with these changes make it desirable to apply the principles of coastal management with geoconservation to the region. This study characterizes the geoforms and analyzes how they have changed over time, in addition to describing some of the challenges for the geoconservation of the area. A geomorphological analysis was performed in this study, focusing on the identification and characterization of aeolian landforms and landform units present in the Itapeva dunefield. Recent satellite imagery, field observations, and photographs were used to conduct this research. The results show that the main aeolian depositional units present in the Itapeva dunefield are reversing transverse dunes, U-shaped sub-parabolic dunes, precipitation ridges, nebkhas, deflation plains, vegetated transgressive sand sheets, and foredunes. Erosional features such as blowouts occur mainly in the foredune area and/or are associated with nebkhas/remnant knobs. Understanding the importance of geoconservation within coastal management can be an important step toward the preservation of the few sectors comprising dunefields in Brazil. To benefit the Park's sustainable development, it is prudent to promote geodiversity, geoconservation, and geotourism, incorporating these principles into coastal management.
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dune conservation and even dune restoration. The environmental legislation
of Rio Grande do Sul (South of Brasil) establishes a Permanent Preservation Area
of 60-m minimum width that should be protected in the coastal dune systems. This
study shows the implementation of a coastal management plan in Osório
Municipality (N of Rio Grande do Sul) for the restoration of the foredune. The
analysis of previous evolution (1997–2010) of the dune field showed widths lower
than the legal requirement and decreasing in the last years. Then, a dune restoration
plan was designed and implemented in 2011. The measures included the planned
retreat of the road located back the foredune, channelization of the northern
whashout’s mouth with a structure under the foredune, installation of sand fences
and control of the pedestrian accesses to the beach by both a pathway and a footbridge.
Finally, efficiency of the management plan was assessed by monitoring
(2011–2016) the foredune evolution, which permitted to conclude a satisfactory
result. Only the foredune sector close to the washout’ mouth did not achieve the
expected minimum width, but it can be considered acceptable considering its higher
sedimentary dynamics, the inherent difficulties of these structures and the short
monitoring period from the implementation of the plan.
of joint action between the Environment Ministry and the Planning Ministry. This project articulates the three spheres of the government (federal, state, and municipal) and society. Its actions seek the management of the coastal spaces, approaching the
environmental and heritage politics. The construction of a Plan for the Integrated Management of the Coastline occurs through workshops with the development of methodologies of diagnosis construction, classification and formulation of scenarios. The classification of the coastline integrates the strategic planning, which will subsidize the decision making process to reach the desired scenarios. Araranguá municipality started its workshops in October 2014, with lectures and discussions between technicians from the federal and state governments, and coordination by the municipal government. During the project period, a field day and more than 40 workshops were developed, which had the participation of the community and public managers.
As a result of the workshops, the coastline was sectored by its landscape, typology (exposed, semi-exposed, and sheltered), and levels of occupation in five sectors (S1 to S5). The project identified 40 problems in the area, some recurrent in all sectors and a few specific of some places. In order to solve these problems, 80 actions and measures with different priorities were defined. From the workshops of the Orla Project, it was possible to identify the need to create rules for the use of Araranguá coastline, thus enabling its conservation and helping its sustainable development.