Assessing erosion and sediment removal in the Isla Salamanca coastal barrier: implications for the Barranquilla-Ciénaga highway and coastal marine biodiversity – Colombia

The Isla Salamanca coastal barrier on the Colombian Caribbean coast faces significant erosion, driven by climate change-induced, sea level rise and human activities such as highway construction. The Barranquilla-Ciénaga highway, particularly at kilometers 19 and 29, is at risk, with severe consequences for the region’s socio-economic and environmental well-being. Human interventions like the highway construction and seawall installations have disrupted the natural coastal dynamics, leading to increased erosion rates. The study, conducted between 2004 and 2021, reveals that the Isla Salamanca coastal barrier is experiencing substantial transgression, with erosion rates peaking at -16.1 m·yr− 1. The highway protection measures, with seawall construction, have proven inadequate, exacerbating erosion downstream. The mangrove loss due to hydrological changes and increased salinity is further threatening the fragile ecosystem. The research emphasizes the importance of considering biodiversity loss in the context of rapid erosion rates. The region, declared a Ramsar Site and Biosphere Reserve, hosts vital ecosystems like mangroves and dunes, whose destruction negatively impacts marine biodiversity. The study suggests the relocation of the highway, acknowledging the challenges of preserving wetlands and mangroves in the process. Balancing the need for infrastructure with ecological preservation is essential, and the study proposes comprehensive solutions, including shoreline management, ecosystem-based protection, and community involvement. The goal is to mitigate erosion’s adverse effects on biodiversity, habitat integrity, and the overall health of this ecologically sensitive regio

Turismo e degradação na orla do Rio Grande do Sul: conflitos e gerenciamento

Economic, ecological and socio-cultural interests always come into conflict within the Sustainable Coastal Development. In order to ensure the sustainability and vitality of these three functions simultaneously, planning and management actions are necessary to reduce these conflicts. Coastal environment is of great importance for the tourism industry, so it is necessary to assure socio-cultural and ecological conservation as the only way to maintain economic development. The municipality of Xangri-lá, which has its economy focused on tourism, is starting dunes management activities and reorganizing the use and occupation of the beach. This paper aims to detail the current situation of the coast of Xangri-lá and the conflicts as a result of tourism in this area. The problems and conflicts were evaluated through field observations and morphodynamic controls (profile of the beach and vegetation). During this period itwas found that there is an aggravation of erosion on the dune system, caused by storms and a vegetation decrease. As a result, dunes decreased in size and width. Associated to this, the pressure of occupation and the lack of infrastructure related to tourism were the main problems found along the coast. Another problem is the dune system distortion caused by the trampling of native vegetation, exotic vegetation invasion, buildings, condominiums, gardens and kiosks. Furthermore, the users’ neglect about the importance of this environment has been leading to the accumulation of garbage. The immediate measures that should be taken to avoid harm to economic activities due to coast erosion and degradation are foredunes recovery, improving beach access and suitable locations for garbage

Impactos no sistema de dunas: dinâmica natural versus interferência antrópica

The shoreline of Capão da Canoa, RS, alternates densely populated areas with non urban empty spaces that still have their natural features preserved. This paperwork aimed to evaluate the foredunes vulnerability, by field evaluation along the shoreline in wintertime and summertime, using a field checklist. After rating some parameters, a Vulnerability Index was established for each profile. The highest values matched the most densely populated areas in that municipality, due to the position of the urban area that often shortens the width of the foredune ridges. The superiority of the wintertime vulnerability index when compared to summertime, changes the consensus about the human interference as the main vector of vulnerability. The major factors contributing to foredune degradation were: beach condition during winter time and use pressure, during summertime, indicating the high vulnerability associated with some profiles along the shoreline.A orla de Capão da Canoa, RS, intercala áreas de alta densidade ocupacional com áreas não urbanizadas que preservam suas características naturais. Neste trabalho, buscou-se analisar o índice de vulnerabilidade das dunas frontais, a partir de levantamentos de campo realizados no inverno e verão, utilizando-se uma lista de parâmetros. A partir da taxação destes, atribuiu-se um índice de vulnerabilidade para cada perfil. Os valores mais altos coincidiram com as áreas mais urbanizadas do município, devido à posição da urbanização que reduz a largura dos cordões de dunas frontais. A superioridade dos valores do índice de vulnerabilidade de inverno ao de verão altera o consenso sobre a interferência humana como principal vetor de vulnerabilidade. Os fatores que mais contribuíram para a degradação das dunas frontais foram: a condição de praia, no inverno, e a pressão de uso, no verão, indicando a alta fragilidade de alguns perfis ao longo da orla

Impacts on the dunes system: natural dynamic versus anthropogenic interference

The shoreline of Capão da Canoa, RS, alternates densely populated areas with non urban empty spaces that still have their natural features preserved. This paperwork aimed to evaluate the foredunes vulnerability, by field evaluation along the shoreline in wintertime and summertime, using a field checklist. After rating some parameters, a Vulnerability Index was established for each profile. The highest values matched the most densely populated areas in that municipality, due to the position of the urban area that often shortens the width of the foredune ridges. The superiority of the wintertime vulnerability index when compared to summertime, changes the consensus about the human interference as the main vector of vulnerability. The major factors contributing to foredune degradation were: beach condition during winter time and use pressure, during summertime, indicating the high vulnerability associated with some profiles along the shoreline

Tourism and Degradation in the Coastline of Rio Grande do Sul: Conflicts and Management

O desenvolvimento sustentável da orla marinha põe em conflito os interesses econômicos, ecológicose socioculturais. Para garantir a sustentabilidade e a vitalidade destas três funções de forma simultânea,tornam-se necessárias ações de planejamento e gestão de modo a reduzir estes conflitos. A importânciadeste ambiente para a indústria do turismo possui uma necessidade de preservação sociocultural econservação ecológica como única forma de manter o desenvolvimento econômico. O município deXangri-lá, que apresenta sua economia voltada para a área de serviços ao turismo e ao veraneio, estáiniciando suas atividades de manejo das dunas e uso e ocupação da faixa de praia. Este trabalho tem comoobjetivo detalhar a situação atual da orla marinha do município de Xangri-lá e os conflitos existentes emdecorrência do turismo na região. Para tanto, foram realizadas investigações dos problemas e conflitosexistentes na orla marinha através de observações de campo, de perfis topográficos e de vegetação.Durante este período, constatou-se o agravamento da erosão sobre o sistema de dunas, ocasionadapelas tempestades e pela diminuição da vegetação, resultando na sua diminuição em tamanho e largura.Associadas a isso, a pressão da ocupação e a falta de infraestrutura de suporte ao turismo e ao veraneioforam dos principais problemas encontrados na orla. Outro agravante é a descaracterização do sistemade dunas, causado pelo pisoteio da vegetação nativa, invasão de vegetação exótica, construções de condomínios,jardins e quiosques. Além disso, o descaso dos usuários frente à importância deste ambientetem levado ao acúmulo de resíduos sólidos. As medidas imediatas para o não comprometimento dasatividades econômicas frente à erosão e à degradação da orla estão na recuperação das dunas frontais,melhorias de acesso à praia por meio da manutenção adequada dos sangradouros e passarelas e locais adequados para dispor os resíduos sólidos, além da comunicação como fonte geradora de informação econhecimento sobre esta problemática e suas consequências para a sociedade.Economic, ecological and socio-cultural interests always come into conflict within the SustainableCoastal Development. In order to ensure the sustainability and vitality of these three functions simultaneously,planning and management actions are necessary to reduce these conflicts. Coastal environmentis of great importance for the tourism industry, so it is necessary to assure socio-cultural and ecologicalconservation as the only way to maintain economic development. The municipality of Xangri-lá, whichhas its economy focused on tourism, is starting dunes management activities and reorganizing the useand occupation of the beach. This paper aims to detail the current situation of the coast of Xangri-lá andthe conflicts as a result of tourism in this area. The problems and conflicts were evaluated through fieldobservations and morphodynamic controls (profile of the beach and vegetation). During this period itwas found that there is an aggravation of erosion on the dune system, caused by storms and a vegetationdecrease. As a result, dunes decreased in size and width. Associated to this, the pressure of occupationand the lack of infrastructure related to tourism were the main problems found along the coast. Anotherproblem is the dune system distortion caused by the trampling of native vegetation, exotic vegetationinvasion, buildings, condominiums, gardens and kiosks. Furthermore, the users’ neglect about the importanceof this environment has been leading to the accumulation of garbage. The immediate measures thatshould be taken to avoid harm to economic activities due to coast erosion and degradation are foredunesrecovery, improving beach access and suitable locations for garbage

Gestión Costera Desintegrada - propuesta para un cambio de paradigma en el municipio de Araranguá (Santa Catarina, Brasil)

Brasil posee un conjunto legal y normativo de las tres esferas de gobierno que regulan usos y actividades en la zona costera, que notoriamente apuntan a la municipalización de la gestión. Entre los instrumentos disponibles para la gestión ambiental se destacan: el Plan de Gestión Integrada de la Orla (PGI); las acciones de gestión puntuales; las zonificaciones existentes; y las Unidades de Conservación (UCs). El inventario y la discusión de estos instrumentos para el municipio de Araranguá (SC), se apoyaron en los archivos del Poder Público Municipal y en el proceso de implementación del Proyecto Orla. Este último tiene como resultado el PGI que resulta en la creación de tres UCs municipales, y la zonificación del Plan Director Municipal. Existe el Comité Gestor Municipal de la Orilla de Araranguá, que debería acompañar, evaluar y revisar la implementación de las acciones del PGI, sin embargo, reivindica mayor visibilidad y autonomía. La superposición jerárquica en la gestión de la costa municipal desfavorece la integración de las acciones, los grupos, y la toma de decisiones. El acoplamiento de los Planes de Manejo de las UC a las políticas de gestión puede darse con la construcción de un Plan de Manejo Integrado de las UCs q ue incluya los objetivos del Plan Municipal de Gestión Costero, aún no elaborado, componiendo un Plan de Manejo y Gestión Integrada del Mosaico de UCs Costeras de Araranguá. Esta herramienta constituiría un avance inédito en la gestión costera nacional, pues haría la integración de todos los instrumentos que existen

Coastal dune management : the use of geographic information system (GIS) in the development of management plans in the coast of Rio Grande do Sul, Brazil

Constituídas por grandes acumulações de areia, as dunas frontais são feições naturais da maioria das praias arenosas. As áreas de dunas são consideradas Áreas de Proteção Permanente (APPs) no Brasil, e, para a conservação desses ambientes, faz-se necessário o estabelecimento de planos, programas e medidas governamentais orientados a disciplinar os seus usos e/ou manejos. O desenvolvimento de projetos para a gestão do sistema de dunas deve incluir um diagnóstico do ambiente (características naturais e o grau de intervenção humana), a tendência das mudanças e as ações para manutenção ou recuperação do sistema. O objetivo deste trabalho é demonstrar a potencialidade do uso de um Sistema de Informações Geográficas (SIG) para o diagnóstico ambiental de dunas, bem como salientar a importância da integração de dados regionais em ambiente SIG, a fim de se obter melhores resultados para subsidiar a tomada de decisão na elaboração de planos de gestão para o Gerenciamento Costeiro Integrado, por meio de estudos de caso de duas cidades no litoral do estado do Rio Grande do Sul, sul do Brasil (municípios de Capão da Canoa e Arroio do Sal). O uso de um SIG permite atualizações em várias escalas de tempo e também a análise conjunta de múltiplos dados de diferentes fontes. Essas características auxiliam os trabalhos na região costeira, ambiente com uma grande dinâmica de formas e processos. Para a caracterização, o diagnóstico e o planejamento das áreas de estudo, dados primários e secundários das duas áreas foram coletados e integrados em ambiente SIG, e, assim, pôde-se dividir os ambientes em diferentes setores, possibilitando o planejamento das intervenções necessárias em cada um deles. A espacialização das intervenções sugeridas permitiu sua visualização em mapas, sendo esta informação inserida como um novo plano de informação no projeto em SIG. Algumas das intervenções sugeridas em alguns locais visando à manutenção/recuperação do sistema de dunas incluem: passagem de tubulações abaixo da crista da duna (para a passagem condicionada de cursos d’água), construção de passarelas onde a passagem de pedestres é intensa (para ordenar o acesso à praia), remoção de vegetação exótica etc. Os resultados obtidos demonstram a possibilidade do uso de um SIG nos estudos de gestão costeira, gerando bons resultados no diagnóstico e planejamento das duas áreas de estudo. Como produto final dos planos de manejo desenvolvidos, todos os dados coletados e gerados são disponibilizados em arquivos no formato SIG, bem como em formato de planilha, junto com o relatório descritivo. No âmbito municipal, as vantagens encontram-se na facilidade de armazenamento e disponibilização dos dados, além de proporcionar a fácil modificação destes e também o acompanhamento da evolução dos projetos. A utilização de SIG também pode promover e facilitar a troca de informações entre as instituições e, a longo prazo, pode permitir a integração de todas as informações em um único banco de dados, podendo auxiliar na tomada de decisão dos órgãos municipais, estadual e federal.Foredunes are geomorphological features present in most of the sand beaches around the world. Under the Brazilian law, dunes are considered Permanent Protection Areas and, for conservation of these environments, it is necessary the establishment of plans, programs and measures by the government to discipline their use and management requirements. The development of projects for dune system management should include an environmental diagnosis (natural characteristics and human intervention degree), the trend of changes and the actions for maintenance or recovery of the system. The aim of this work is to evidence the potential of using a Geographic Information System (GIS) for the environmental diagnosis of dunes, as well as stress the importance of regional data integration within a GIS, for the purpose of obtaining better results to support decision making in the development of management plans for integrated coastal zone management. Study cases of two coastal cities in the State of Rio Grande do Sul, southern Brazil (Capão da Canoa and Arroio do Sal cities), are shown. The use of GIS allows updates at several time scales and also the joint analysis of multiple data from different sources. These characteristics assist work in coastal zones, an environment with highly dynamic forms and processes. For the characterization, diagnosis and planning of the two study areas, primary and secondary data were collected. Secondary data consists of bibliographic and cartographic search, and remote sensing data. Primary data consists of field observations, control points collected with GPS, photographic records (beach access, watercourses, irregular occupation, beach uses, dune uses, etc.), topographic data and vegetation identification. After collection, data were inserted in data layers and integrated in the GIS project. Using geoprocessing tools it was possible to calculate areas, measure foredune width and delimit the boundaries of Permanent Protection areas (using distance criteria), leading to further information to be obtained/added in the GIS. Distance criteria for delimitation of Permanent Protection areas were based in the law of the state environmental agency (FEPAM). For the city of Capão da Canoa, increases in sea level caused by storm surge were modelled in the GIS, in order to identify foredune areas susceptible to degradation. Results showed that water courses that cross the dune system are the preferential erosion zones in storm surge events. An evaluation based in the mapped elements and field observations, allowed the assignment of a coastal vulnerability index to each 500 meters beach segment. The higher the vulnerability index, the greater the fragility of the dune system. The areas with the highest index are the ones in which greater efforts are required (interventions/management). In the studied areas, these indexes allowed the planning of interventions required for each beach sector. Both cities have an extensive shoreline and dune areas affected by erosion (caused by storm surge effects, displacement of watercourses, planting of exotic vegetation and lack of planning for the shoreline – with disordered use of this natural system). A well developed urban area is present in Capão da Canoa city, where a discontinuous and highly segmented dune area exists. Preserved sections occur mostly in the non-urban areas. In Arroio do Sal city, there is an extensive and well preserved shoreline and dune system. The major problems affecting dune system in this city are erosion by storm surge and planting of exotic vegetation. With the environmental diagnosis and the vulnerability index for each beach sector, management proposals in different sectors of the shoreline were performed, and spatialization of the suggested actions/interventions was implemented in the GIS. This spatialization allowed visualization of all the beach sectors in maps, and this information was also added to the GIS project as new data layers. For dune system integrity maintenance/recovery in some sectors, some of the suggested interventions include pipe passing under the frontal dune crest (for controlled passage of watercourses), construction of walkways where the crosswalk is very intense (ordering the access to the beach), removal of exotic vegetation, etc. The results demonstrate the possibility of using GIS in coastal management studies, showing good results in the diagnosis and planning of the two study areas. As a final product of the management plans developed, all the collected and generated data are provided in GIS file format and in spreadsheets in a PDF report. At the municipal level, the advantages are ease of storage and availability of data, facilitating data modification in case of scenario alteration for the shoreline. The use of a GIS can also promote and facilitate the exchange of information between institutions and, in the long term, can allow the integration of all information into a single database to assist in decision making at the municipal, state and federal agencies. Keywords: coastal management, geospatial technology, database, coastal modelling

Gestão integrada de unidade de conservação costeira - parque estadual de itapeva, torres-rs, Brasil

The National System of Conservation Units was created in order to preserve fragile environments that need to be protected in Brazilian territory. In Torres municipality, located in the northern coast of Rio Grande do Sul state (RS), there are beaches with singular scenic attractivity in southern Brazilian coast, due to their natural characteristics, and five conservation areas/units. The Itapeva State Park (Parque Estadual de Itapeva – PEVA, in Portuguese), where this study was conducted, was created in 2002, in order to protect dune fields, swamps and native vegetation in the RS coastal zone. However, anthropic pressure and its consequences continues until today. In this study a diagnosis of the environmental impacts in the north limit of the PEVA conservation unit was carried out, as well as the local community characterization and its relationship with the environment in which they live, and a survey of existent management actions in the city was conducted, in order to subsidize the conservation unit management. The methods used were interviews, field observations and analysis of documents

Process control in the geneses and evolution of a lagoon-barrier system inside of the patos lagoon, south of Brazil

The origin and geological evolution of a complex of a beach ridgeplain in the Feitoria lagoon-barrier, located on the western margin of the southern cell Patos lagoon, Brazil was influenced by the interactions between the alocyclic (climate change and relative sea level) and autocyclic (sediment supply, waves, longshore drift and storm surges) forcing. The study of this regressive beach ridgeplain included the analysis of orthophotos; topographic detail (PRO-XRS Trimble®-post-processed); and shallow geophysical data with Ground Penetrating Radar (GPR), 150, 200 and 400 MHz antennae, combined with facies analysis and radiocarbon dating (AMS) and Optically Stimulated Luminescence (OSL) from shallow borehole samples. The analysis of orthophotos allowed for the definition of at least nine morphologically distinct series of progradation, marked by truncations of progressive orientation changes. The integration of topographically corrected GPR data, sedimentary records, and geochronological data determined the beginning of the progradation occurred at 7.2 kaBP. At the beginning of progradation, the low tide terrace was at the height of 1.9m (EGM96) Above the Sea Current Level (ASCL). The swash zone was in the 2.5m, and the crest reached 4.3m ASCL. Currently, the low tide terrace quota is -0.4m, the swash zone to 0.3m and the crest reaches 2.1m ASCL. Among other factors, the fall of the lagoon base levels was associated with sea level fall during the Holocene regression. However, crest construction control is dependent on the lagoon base level oscillation, which in turn is controlled by the precipitation regime and storms surges. Moreover, these results suggest that the orientation of the ridges was controlled by changes in the internal lagoon hydrodynamics, due to the progressive narrowing of the lagoon connection with the open ocean