Abstract — The use of submerged vanes has been experimentally validated as an effective method for controlling local scour and stabilizing riverine structures. This study evaluates the efficacy of submerged vanes in mitigating local erosion around a square bridge pier. Four experiments were conducted under controlled conditions in the sedimentation channel of the Laboratory of the Faculty of Civil and Environmental Engineering at the National Polytechnic School in Quito, Ecuador. Acrylic submerged vanes were installed upstream of the pier at a 15° attack angle relative to the flow direction, aiming to modify the velocity distribution and sediment transport dynamics. The experimental results showed that submerged vanes reduced the maximum scour depth by up to 60 % compared to tests without vanes, with an average reduction of approximately 58 %. This significant reduction was attributed to the generation of vortices that redistributed sediment, resulting in shallower and more stable scour holes. Furthermore, the average sediment transport downstream decreased by approximately 40 %, further validating the vanes' efficiency in controlling erosive processes. The vanes demonstrated consistent effectiveness across varying flow rates and sedimentation conditions, underscoring their practical adaptability. By modifying flow dynamics and reducing bed shear stress, the vanes provided reliable scour protection regardless of the hydraulic conditions tested. This study highlights the submerged vanes' potential as a viable, economical, and innovative solution for protecting riverine infrastructures, particularly bridge piers, against erosive forces. Their scalability and adaptability to different hydraulic conditions make them suitable for mitigating scour in river systems with high sediment transport activity and for retrofitting existing infrastructure to enhance its stability. This research contributes to the body of knowledge on local scour mitigation by presenting a replicable experimental methodology and emphasizing the practical applicability of submerged vanes. in hydraulic engineering. The findings suggest that submerged vanes are not only effective but also cost-efficient, making them a promising alternative to traditional scour protection methods such as riprap or aprons.

Resumen — El uso de paneles sumergidos ha sido validado experimentalmente como un método efectivo para controlar la erosión local y estabilizar estructuras fluviales. Este estudio evalúa la eficacia de los paneles sumergidos en la mitigación de la erosión local alrededor de una pila de puente cuadrada. Se realizaron cuatro experimentos bajo condiciones controladas en el canal de sedimentación del Laboratorio de la Facultad de Ingeniería Civil y Ambiental de la Escuela Politécnica Nacional en Quito, Ecuador. Los paneles sumergidos de acrílico se instalaron aguas arriba de la pila con un ángulo de ataque de 15° respecto a la dirección del flujo, con el objetivo de modificar la distribución de velocidades y la dinámica del transporte de sedimentos. Los resultados experimentales mostraron que los paneles sumergidos redujeron la profundidad máxima de socavación en hasta un 60 % en comparación con las pruebas sin paneles, con una reducción promedio de aproximadamente 58 %. Esta reducción significativa se atribuyó a la generación de vórtices que redistribuyeron el sedimento, resultando en cavidades de socavación más someras y estables. Además, el transporte promedio de sedimentos aguas abajo disminuyó aproximadamente un 40 %, lo que valida aún más la eficiencia de los paneles en el control de los procesos erosivos. Los paneles demostraron una efectividad consistente frente a diferentes caudales y condiciones de sedimentación, subrayando su adaptabilidad práctica. Al modificar la dinámica del flujo y reducir las tensiones cortantes del lecho, los paneles proporcionaron una protección confiable contra la socavación, independientemente de las condiciones hidráulicas evaluadas. Este estudio destaca el potencial de los paneles sumergidos como una solución viable, económica e innovadora para proteger infraestructuras fluviales, particularmente pilas de puentes, contra fuerzas erosivas. Su escalabilidad y adaptabilidad a diferentes condiciones hidráulicas los hacen adecuados para mitigar la socavación en sistemas fluviales con alta actividad de transporte de sedimentos y para reacondicionar infraestructuras existentes, mejorando su estabilidad. Esta investigación contribuye al cuerpo de conocimiento sobre la mitigación de la socavación local al presentar una metodología experimental replicable y resaltar la aplicabilidad práctica de los paneles sumergidos.

Abstract — In Ecuador, the electricity sector has undergone significant transformation over the past 15 years, with a marked increase in renewable energy capacity, particularly hydropower, which grew from 1,707 MW in 2000 to 5,100 MW in 2022. This shift, driven by the need to diversify the energy grid and reduce fossil fuel dependence. Despite its importance, the Coca Codo Sinclair project with 1,500 MW has faced several technical, environmental, and social challenges, including erosion and structural issues, raising concerns about its long-term sustainability. This article aims to analyze these challenges, their causes, impacts, and potential solutions, providing insights for future hydropower developments in similar regions. Coca Codo Sinclair is an example of the ambition of a government that did not follow the recommendations of technical studies on the maximum capacity that could be generated by a plant that now has more problems than advantages, analyzing all the associated drawbacks that the largest hydropower plant in Ecuador, it is important to understand that technical criteria must prevail over political decisions. In order to keep the more than 3 billion dollars of investment going, urgent action is required on CCS remediation works, with a combination of investments in repairs and maintenance activities, improvements in management and governance of the project, therefore, currently the largest plant in Ecuador represents a time bomb that can collapse due to any of the various problems.

Resumen — En Ecuador, el sector eléctrico ha experimentado una importante transformación en los últimos 15 años, con un marcado de la capacidad de energía renovable, en particular la hidroeléctrica, que pasó de 1.707 MW en 2000 a 5100 MW en 2022. Cambio, impulsado por diversificar la matriz energética y reducir la dependencia fósil. A pesar de su importancia, el proyecto Coca Codo Sinclair con 1500 MW ha enfrentado varios desafíos técnicos, ambientales y sociales, incluidos problemas de erosión y estructurales, lo que genera preocupaciones sobre su sostenibilidad a largo plazo. Este artículo tiene como objetivo analizar estos desafíos, causas, impactos y posibles soluciones, brindando perspectivas para futuros desarrollos hidroeléctricos en regiones similares. Coca Codo Sinclair es un ejemplo de la ambición de un gobierno que no siguió las recomendaciones de los estudios técnicos sobre la capacidad máxima que genera una planta que ahora tiene más problemas que ventajas, analizando todos los inconvenientes asociados que tiene la hidroeléctrica más grande de Ecuador, es importante entender que los criterios técnicos deben prevalecer sobre las decisiones políticas. Y, para mantener en marcha los más de 3 mil millones de dólares de inversión, se requiere actuar urgentemente en obras con una combinación de inversiones en actividades de reparación y mantenimiento, y mejoras en la gestión y gobernanza del proyecto, pues actualmente la planta más grande del Ecuador representa una bomba de tiempo que puede colapsar por cualquiera de los diversos problemas.

Abstract The aim of this study was to assess the effect of a chlorhexidine digluconate solution (CHX) applied as an antiproteolytic agent for controlling erosive tooth wear or as part of the adhesive treatment on long-term bond strength to eroded dentin. Dentin specimens were abraded with a 600-grit silicon carbide (SiC) paper for 1 min (sound dentin - S), subsequently treated with 2% CHX for 1 min (with excess removed, followed by a 6-hour rest), and eroded by exposure to Coca-Cola for 5 min, three times a day, for 5 days (CHX-treated and eroded dentin - CHXE), or only eroded (eroded dentin - E). The specimens were acid-etched (15 s), rinsed (30 s), dried (15 s), and rehydrated with 1.5 μL of distilled water for 1 min, with excess removed (control - S.C/CHXE.C/E.C) or 2% CHX (S.CHX/CHXE.CHX/E.CHX). Adper Single Bond 2 was scrubbed twice on the surface for 15 s each and then light-cured for 10 s, and resin composite cores were built up. Specimens were sectioned into beams and microtensile bond strength was tested (μTBS; 0.5 mm/min) immediately or after 18-month aging. Failure modes were analyzed using a digital microscope. Data (μTBS/MPa) were analyzed by three-way ANOVA, followed by Tukey’s test (α = 0.05). μTBS to E and CHXE, irrespective of the rehydration solution and aging period, were equivalent to each other and lower than that to S. CHX as the rehydration solution reduced immediate and long-term µTBS to S. Aging reduced μTBS. By controlling tooth wear or interface aging, CHX could not influence long-term bonding to eroded dentin.

ABSTRACT Purpose: The degenerative joint disease is a temporomandibular disorder. By analysing texture parameters, it becomes possible to characterize and differentiate various tissues, based on their textural properties according to cone-beam computed tomography (CBCT). This study evaluated degenerative diseases in the temporomandibular joint through texture analysis. Methods: Eighty images of the jaw condyle with three types of degenerative diseases, flattening, osteophytes, erosion and control group were analysed, obtained through CBCT. The analyses were carried out through texture analysis with three regions of interest (ROIs) corresponding to specific bone sites. The scans were exported to MaZda software, in which the ROIs were delimited following previously marked contours, and the co-occurrence matrix values were calculated for selected texture analysis parameters. Results: The erosion group showed a significantly different behaviour from the other groups for all analysed parameters. Conclusion: This study highlights the potential of texture analysis in characterizing medullary bone changes in condyles affected by erosion. Texture analysis allows for a more comprehensive assessment of bone condition on CBCT images. These results have implications for early detection and monitoring of degenerative changes in the temporomandibular joint, thus allowing preventive intervention and personalized treatment planning, improving the prognosis of the disease.

ABSTRACT Objective: To investigate the effect of fluoridated solution based on silver nanoparticles (AgNano) associated or not with toothpaste containing high fluoride concentration (TP) on dental erosion. Material and Methods: Ninety-six enamel blocks from bovine incisors were prepared and analyzed for microhardness and initial roughness. Then, divided into 8 experimental groups (n = 12): G1 - brushing with water (H2O); G2 - brushing with TP; G3 - AgNano + TP; G4 - AgNano + H2O; G5 - SDF + TP; G6 - SDF + H2O; G7 - FV + TP; G8 - FV + H2O. SDF, AgNano, and FV were applied and, after 24 hours, all samples were submitted to erosive challenge with 0.3% citric acid (pH 2.6) and brushing with TP or H2O for 5 days. After treatments and erosion challenge, microhardness and roughness were again evaluated. The data were statistically analyzed by ANOVA followed by Tukey's test (microhardness) and Kruskal-Wallis test (roughness), α=0.05. Results: There was no difference between treatments (AgNano, SDF, and FV), (p>0.05); however, brushing with toothpaste with high fluoride concentration significantly decreases loss of enamel microhardness. Conclusion: AgNano associated or not with toothpaste containing high fluoride concentration was not able to reduce dental erosion in the enamel, as well as SDF and FV. Objective (AgNano (TP Methods Ninetysix Ninety six Then n 12 12) G HO H O (H2O) 2 hours 03 0 3 0.3 pH 2.6 26 6 days evaluated Tukeys Tukey s (microhardness KruskalWallis Kruskal Wallis roughness, , (roughness) α005 α 05 α=0.05 Results FV, FV) p>0.05 p005 p (p>0.05) however Conclusion 1 (H2O 0. 2. (roughness α00 α=0.0 p>0.0 p00 (p>0.05 α0 α=0. p>0. p0 (p>0.0 α=0 p>0 (p>0. α= p> (p>0 (p> (p

ABSTRACT Objective: To evaluate the properties of fermented milk beverages containing probiotics and their potential demineralization on enamel after consumption. Material and Methods: Seven fermented milks were analyzed by titratable acidity and pH, and five were considered for erosive cycling. The beverages' calcium (Ca) and Phosphorus (P) were measured. For measurement of potential erosive, bovine dental enamel blocks (n=8) were individually treated (2 min - 4x/day for five days) with 1% citric acid solution pH 3.5 (control) and strawberry, grape, traditional, and orange fermented milk beverages. At treatment intervals, the blocks were immersed in artificial saliva (1h). The samples were evaluated by profilometry and scanning electron microscopy (SEM) at the end of cycling. The results were submitted to ANOVA and 5% Tukey tests. Results: For titratable acidity, the traditional flavor had the lowest value, 3.36 ± 0.46 mmoles, and the grape flavor had the highest value, 10.7 ± 0.1 mmoles. The lowest pH value was the strawberry flavor at 3.61 ± 0.07, and the highest was the orange flavor at 4.10 ± 0.07. The orange flavor showed the highest values of Ca (48.19%) and P (9.69%). The fermented milk beverages promoted surface loss; however, citric acid promoted higher values. Conclusion: Fermented milk is an acidic beverage with variations in inorganic components. Their erosive potential is lower compared with citric acid. Objective consumption Methods cycling (Ca (P measured n=8 n8 n 8 (n=8 2 ( 4xday xday 4x day x days 1 35 3 5 3. control (control intervals 1h. 1h h . (1h) SEM (SEM tests Results 336 36 3.3 046 0 46 0.4 mmoles 107 10 7 10. 01 0. 361 61 3.6 007 07 0.07 410 4 4.1 48.19% 4819 48 19 (48.19% 9.69%. 969 9.69% 9 69 (9.69%) loss however Conclusion components n= (n= (1h 33 04 6 00 0.0 41 4. 48.19 481 (48.19 96 9.69 (9.69% (n 48.1 (48.1 9.6 (9.69 48. (48. 9. (9.6 (48 (9. (4 (9

ABSTRACT The spatial variability of soil attributes in terraced areas is poorly studied in the semi-arid region. Considering that multivariate analysis enhances the diagnosis of spatial variability from geostatistics, soil attributes were studied in different zones between terrace channels in semi-arid region, more precisely in a retention terrace area in Canindé (Ceará, Brazil). Soil samples (n = 100) were collected at depths of 0.0 - 0.1 and 0.1 - 0.2 m for descriptive and geostatistical analysis. For multivariate analysis, samples from three zones relative to the terrace channel (Upper, Middle, and Lower) in the 0.0 - 0.2 m layer were considered, with 30 replicates. There was spatial dependence of soil attributes in the two layers studied. Near the channel, in the respective layers, there was higher clay content (13.7% and 14.7%) and higher degree of flocculation (61.3% and 71.7%) compared to the other zones. Water-dispersible clay was higher in the Upper zone (6.5% and 7.7% in the respective layers), while the Middle zone showed higher potential acidity in the evaluated layers (4.8 and 4.5 cmolc dm-3, respectively) compared to the other zones. In the multivariate analysis, there were highlights for the higher sum of bases in the Upper zone (18.9 ± 0.8 cmolc dm-3), higher sand content in the Middle zone (72.6 ± 0.6%), lower potential acidity (2.1 ± 0.2 cmolc dm-3) and higher phosphorus content (12.8 ± 3.0 mg kg-1) in the Low zone. The zone above the terrace channel loses mainly clay and requires practices to increase water and nutrient retention. semiarid semi arid region geostatistics Ceará, Ceará (Ceará Brazil. Brazil . Brazil) n 100 00 0 0. 01 1 02 2 Upper, (Upper Lower considered 3 replicates 13.7% 137 13 7 (13.7 14.7% 147 14 61.3% 613 61 (61.3 71.7% 717 71 Waterdispersible Water dispersible 6.5% 65 6 5 (6.5 77 7.7 , layers) 4.8 48 4 8 (4. 45 4. dm3, dm3 dm 3, dm-3 respectively 18.9 189 18 9 (18. 08 72.6 726 72 (72. 0.6%, 06 0.6% 0.6%) 2.1 21 (2. 12.8 128 12 (12. 3. kg1 kg kg-1 10 13.7 (13. 14.7 61.3 (61. 71.7 6.5 (6. 7. (4 dm- 18. (18 72. (72 0.6 2. (2 12. (12 kg- 13. (13 14. 61. (61 71. 6. (6 ( (1 (7

RESUMEN Entre las consecuencias del cambio climático en los sistemas costeros está el cambio del nivel del mar, el cual funciona como una línea base sobre la cual opera una variedad de procesos costeros, a diferentes escalas de tiempo y espacio. La presente investigación tiene por objetivo calcular la tasa histórica y actual de ascenso del nivel del mar a partir de datos de la estación mareográfica Limón. Para esto se utilizaron dos métodos: el análisis de regresión lineal simple y una descomposición de series temporales. Como resultado se obtuvo una tasa de cambio del nivel del mar para el período 1952 a 1968 de 2.32 mm/año con el primer método y 3.41 mm/año para el segundo método, que es consecuente con las publicaciones existentes. En el caso del período actual (2009 a 2021) se obtuvo una tasa de 4.18 mm/año para el primer método y 4.28 mm/año con el segundo método. Los resultados obtenidos confirman que existe una tendencia al aumento del nivel del mar en la región estudiada, situación que debe ser considerada al estudiar las transformaciones que están ocurriendo en la costa, como lo son la erosión costera identificada en algunas zonas del Caribe costarricense.

ABSTRACT One of the consequences of climate change is sea level change in coastal systems, which function as a baseline, where a variety of coastal processes operate at different time and space scales. The objective of the present research is to calculate the historic and current rate of sea level rise, from Limon tide gauge station’s data. Two methods were utilized for this purpose: Simple linear regression analysis and time series decomposition; with the first method, a rate of 2.32 mm/yr of sea level change was obtained for the time period 1952 to 1968; with the second one, a rate result of 3.41 mm/yr which is consequent with the existing publications. In the current period (2009 - 2021) a rate of 4.18 mm/yr was obtained with the first method and 4.28 mm/yr with the second method. The results gathered confirm the existence of an upward trend in sea level rise in the studied region. This situation should be considered when studying the transformation taking place in the coast, such as the coastal erosion identified in some of the Costa Rican Caribbean zone.

RESUMEN Los manglares están expuestos a amenazas como el aumento del nivel del mar, la erosión costera, el aumento de la frecuencia e intensidad de eventos extremos, además de presiones socioeconómicas. Este estudio tuvo como objetivo realizar un análisis de vulnerabilidad y riesgo climático para el socioecosistema de manglar de Colombia. Se utilizaron 22 indicadores de amenaza, 8 de sensibilidad y 18 de capacidad adaptativa; mediante un análisis numérico multivariado se generaron los índices de vulnerabilidad y riesgo climático para los manglares del Pacífico y del Caribe de Colombia. Los manglares que presentaron mayor riesgo en el Caribe se ubicaron en los municipios de Manaure, Tubará y Puerto Escondido, mientras que en el Pacífico estas áreas de alto riesgo se ubicaron en la costa sur, en los municipios de Olaya Herrera, Francisco Pizarro y La Tola, y en la costa norte de Bahía Solano. Los indicadores de amenaza que capturaron la mayor variabilidad del análisis fueron: el aumento del nivel del mar, el cambio en la línea de costa, el cambio en la oferta hídrica, el cambio en la cobertura de manglares por cambio en la línea de costa, el cambio en la temperatura y la precipitación debido a El Niño y La Niña, y la huella humana. Estos resultados son un insumo para la gestión climática de los manglares en Colombia y contribuirán al Programa Nacional de Manglares. Asimismo, podrán contribuir al Plan Nacional de Restauración de Manglares, la Contribución Nacionalmente Determinada de Colombia (NDC), la Estrategia Climática de Largo Plazo de Colombia E2050, y los Planes Territoriales de Adaptación al Cambio Climático de los departamentos y municipios.

ABSTRACT The mangroves are exposed to threats such as sea level rise, coastal erosion, increase in the frequency and intensity of extreme events, in addition to socioeconomic pressures. This study aimed to carry out a vulnerability and risk climate analysis for the Colombian mangrove socioecosystem. 22 threat indicators, eight of sensitivity and 18 of adaptive capacity were used, and through multivariate numerical analysis, the vulnerability and climate risk indices for Colombian Pacific and Caribbean mangroves were generated. The mangroves that presented the highest risk in the Caribbean were located in the Manaure, Tubará and, Puerto Escondido municipalities, while in the Pacific these high-risk areas were located on the southern coast in the Olaya Herrera, Francisco Pizarro, and La Tola municipalities, and in the northern coast in the Bahía Solano municipality. The threat indicators that captured the greatest variability in the analysis were: sea level rise, change in the coastline, change in water supply, change in mangrove coverage due to change in the coastline, change in temperature and precipitation due to El Niño and La Niña, and human footprint. These results are input for climate management of mangroves in Colombia and will contribute to the National Mangrove Program. Likewise, it can contribute to the National Mangrove Restoration Plan, the Nationally Determined Contribution of Colombia (NDC), the Long-Term Climate Strategy of Colombia E 2050, and the Territorial Plans for Climate Change Adaptation of the states and municipalities.

Resumen Introducción. La pérdida de suelo es un proceso natural y complejo, el cual se puede potenciar por condiciones climáticas y labores agrícolas como la mecanización. Una forma de suelo (muy poco conocida) se debe al sedimento adherido al producto al momento de la cosecha, el cual se pierde permanentemente de los sembradíos. La cuantificación de este sedimento es un factor adicional a la pérdida de suelo por erosión y los nutrientes que pueden perderse de una parcela. Objetivo. Cuantificar la pérdida de suelo por cosecha del cultivo en dos ciclos de cultivo de cebolla (Allium cepa L.) bajo tres implementos de labranza mecanizada. Materiales y métodos. Se establecieron parcelas (240 m2 cada una) en un diseño de bloques completos al azar, las cuales se sembraron con cebolla. Al momento de la cosecha del cultivo, se recolectó el sedimento adherido a la superficie de los bulbos y se estimaron los valores de pérdida de suelo para las parcelas evaluadas. Se realizaron análisis químicos de fertilidad, utilizando las metodologías KCl-Olsen y C/N total a los sedimentos obtenidos para calcular las pérdidas de nutrimentos y materia orgánica por labores de cosecha. Resultados y discusión. Se cuantificaron cantidades de sedimento entre 594,71 ± 471,93 y 1083,94 ± 78,45 kg ha-1 ciclo-1 que se pierde de los sembradíos de cebolla de forma irreversible. En adición, se pueden perder hasta 3,04 ± 0,27 kg de N, 0,15 ± 0,02 kg de P, y 1,16 ± 0,12 kg de K por hectárea por ciclo de cultivo. Conclusiones. Los resultados obtenidos son pioneros en el estudio de erosión y pérdida de suelo por cosecha del cultivo en Costa Rica, y pueden servir de referencia para futuros estudios de manejo y conservación de suelos.

Abstract Introduction. Soil loss is a natural and complex process that can be exacerbated by climatic conditions and agricultural practices such as tillage. One form of soil loss (which is not well-known) occurs due to sediment adhered to the product at harvest time, which is permanently lost from the fields. Quantifying this sediment is an additional factor to soil loss by erosion and the potential loss of nutrients from farmlands. Objective. To quantify the soil loss due to crop harvesting (SLCH) in two onion (Allium cepa L.) crop cycles under three mechanized tillage implements. Materials and methods. Field plots (240 m2 each) were established following a complete randomized block design, and further planted with onion. Sediment adhered to the surface of the bulbs at the time of harvest was collected, and SLCH values were estimated for the evaluated plots. Fertility analyses (chemical analysis extracted in KCl-Olsen and total C/N) were conducted on the obtained sediments to calculate the loss of nutrients and organic matter due to harvesting activities. Results and discussion. They were quantified sediment values between 594.71 ± 471.93 and 1083.94 ± 78.45 kg ha-1 cycle-1 that are irreversibly lost from the onion fields. Additionally, up to 3.04 ± 0.27 kg of N, 0.15 ± 0.02 kg of P, and 1.16 ± 0.12 kg of K per hectare per cycle can be lost. Conclusions. The results obtained are pioneering in the study of erosion and soil loss due to crop harvesting in Costa Rica and can serve as a reference for future soil management and conservation studies.

Resumo A Bacia do Baixo Rio Acre está localizada em uma área de desflorestamento com implantação de pastagens para pecuária de corte em solos suscetíveis à erosão e clima equatorial. A existência de abatedouros e pecuária de corte implantada no município de Boca do Acre, no Amazonas, é um dos problemas vinculados ao desmatamento da Amazônia Brasileira. Diante desse cenário, foi apresentada uma estimativa de perdas de solo com aplicação da Equação Universal em sistema de informação geográfica. Na metodologia, foi elaborado um banco de dados com informações vetorizadas para extração das áreas dos tipos de solos e cobertura da terra, incluindo a análise espacial de declividades extraídas do modelo digital de elevação. Em decorrência da análise das áreas pelo geoprocessamento ocorrer pela vetorização, foram obtidos os cálculos das parcelas de erosão através de tabelas com os parâmetros adotados pelas referências científicas. Foi constatado que 60% da perda de solo ocorrem na área de agricultura em 11% do território da bacia hidrográfica, sendo predominantemente em áreas de assentamentos rurais do estado do Acre. Como resultado da estimativa, a perda de solos na Bacia do Baixo Rio Acre foi de 386.422 t/ha/ano, com uma produção de 46 milhões de toneladas de sedimentos por ano.

Resumen La cuenca baja del río Acre se ubica en una zona de deforestación con la implementación de pastizales para ganado vacuno en suelos susceptibles a la erosión y clima ecuatorial. La existencia de mataderos y ganado vacuno en el municipio de Boca do Acre, en el estado de Amazonas, es uno de los problemas vinculados a la deforestación en la Amazonía brasileña. Ante este escenario, se presentó una estimación de las pérdidas de suelo con la aplicación de la Ecuación Universal en un sistema de información geográfica. En la metodología, se desarrolló una base de datos con información vectorizada para extraer las áreas de tipos de suelo y cobertura del suelo, incluyendo el análisis espacial de pendientes extraído del modelo digital de elevación. Como resultado del análisis de las áreas por geoprocesamiento y vectorización, se obtuvieron los cálculos de las parcelas de erosión a través de tablas con los parámetros adoptados por los referentes científicos. Se encontró que el 60% de la pérdida de suelo ocurre en el área agrícola en el 11% del territorio de la cuenca, siendo predominantemente en áreas de asentamientos rurales en el estado de Acre. Como resultado de la estimación, la pérdida de suelo en la cuenca baja del río Acre fue de 386.422 t/ha/año, con una producción de 46 millones de toneladas de sedimentos por año.

Abstract The Lower Acre River Basin is located in an area of deforestation with the implementation of pastures for beef cattle ranching in soils susceptible to erosion and equatorial climate. The existence of slaughterhouses and beef cattle in the municipality of Boca do Acre, in the state of Amazonas, is one of the problems linked to deforestation in the Brazilian Amazon. Given this scenario, an estimate of soil losses was presented with the application of the Universal Equation in a geographic information system. In the methodology, a database was elaborated with vectorized information for the extraction of the areas of the types of soils and land cover, including the spatial analysis of slopes extracted from the digital elevation model. Due to the analysis of the areas by geoprocessing occurring by vectorization, the calculations of the erosion plots were obtained through tables with the parameters adopted by the scientific references. It was found that 60% of the soil loss occurs in the area of agriculture in 11% of the territory of the watershed, being predominantly in areas of rural settlements of the state of Acre. As a result of the estimate, soil loss in the Lower Acre River Basin was 386,422 t/ha/year, with a production of 46 million tons of sediment per year.

Resumo Introdução: A erosão acelerada do solo é uma das principais causas de sua degradação, sendo esta potencializada por atividades antrópicas que reduzem a cobertura do solo e aumentam sua densidade. Objetivo: Ante isso, com o presente estudo objetivou-se quantificar e comparar as perdas de solos por erosão, entre áreas com agricultura convencional e vegetação natural no sítio Potós localizado na zona rural do município de Ubajara, Ceará, Brasil. Metodologia: Para monitorar a erosão foram instalados nove pinos de erosão em cada tratamento, distribuídos em malha triangular, no sentido do declive e entre as fileiras de plantas. O monitoramento ocorreu mensalmente durante os anos de 2020 e 2021. Resultados: As perdas de solos mensais variaram entre 0 e 948,73 Mg ha-1 por mês e foram maiores nos meses mais chuvosos, sendo as maiores perdas registradas no ano com maior precipitação total acumulada.

Resumen Introducción. La erosión acelerada del suelo es una de las principales causas de la degradación del suelo, que se ve reforzada por las actividades humanas que reducen la cobertura del suelo y aumentan su densidad. Metodologia: Por lo tanto, el objetivo de este estudio es cuantificar y comparar las pérdidas de suelo por erosión, entre áreas con agricultura convencional y vegetación natural en el sitio Potós ubicado en la zona rural del municipio de Ubajara, Ceará, Brasil. Resultados. Para monitorear la erosión, se instalan nueve pines de erosión en cada tratamiento, distribuidos en forma triangular, en el sentido de la pendiente, entre las hileras de plantas. El monitoreo se realizará mensualmente durante los años 2020 y 2021. Las pérdidas mensuales varían entre 0 y 948,73 Mg ha-1 mes, siendo las mayores en los meses más lluviosos, registrándose las mayores pérdidas en el año de mayor precipitación total acumulada.

Abstract Introduction. Accelerated soil erosion is one of the major causes of land degradation, which is exacerbated by human activities that reduce soil cover and increase its density. Objective. This study aimed to quantify and compare the levels of soil erosion between areas with conventional agriculture and natural vegetation at the Potós site located in the rural area of the municipality of Ubajara, Ceará, Brazil. Methodology. To monitor erosion, nine erosion pins were installed in each treatment area, arranged in a triangular mesh pattern, in the direction of the slope and between the rows of plants. Monitoring will occur monthly during 2020 and 2021. Results. Monthly losses range from 0 to 948.73 Mg ha-1 month, with the highest losses occurring in the driest months. The greatest losses were recorded in the year with the highest total accumulated precipitation.

Resumen Introducción. El mortiño (Vaccinium floribundum Kunth) enfrenta una erosión genética significativa debido a la presión antrópica en los páramos, lo que ha llevado a la pérdida gradual del conocimiento tradicional del mortiño. En Colombia, la falta de registros específicos ha dificultado la identificación de las especies asociadas, así como la comprensión de la distribución y las condiciones de vida de esta planta. Objetivo. Construir un modelo de distribución geográfica y potencial del mortiño, cuantificar la diversidad vegetal y analizar las especies asociadas, junto con los usos e importancia de la especie en su contexto de vida. Materiales y métodos. El estudio se llevó a cabo en el corregimiento El Encano, Nariño-Colombia, durante el año 2021. Se implementó una metodología de investigación acción participativa, con encuestas, entrevistas, recorridos de campo con la comunidad y talleres participativos. Para desarrollar los mapas de distribución, se emplearon los programas ArcGIS 10.5 y MaxEnt 3.4.4. Los índices de diversidad biológica, como Shannon-Weiner y Simpson, junto con el valor de importancia, se determinaron para evaluar la riqueza de especies. Resultados. La comunidad resaltó el uso del mortiño en alimentación y medicina tradicional. Se identificaron veintiún especies asociadas, el helecho (Blechnum loxense Kunth) fue la más importante. La distribución de V. floribundum se atribuye a condiciones climáticas favorables, con temperaturas entre 8 y 16 °C y un gradiente altitudinal de 2800 a 3200 m s. n. m. Conclusiones. El estudio reveló dos ecosistemas propicios para el mortiño: el bosque altoandino y el páramo. El índice de valor de importancia destaca al helecho como la especie más representativa asociada al mortiño, información valiosa para la conservación y manejo sostenible de estos ecosistemas en la región.

Abstract Introduction. Mortiño (Vaccinium floribundum Kunth) faces significant genetic erosion due to anthropogenic pressure in the páramos, leading to the gradual loss of traditional knowledge about the plant. In Colombia, the lack of specific records has hindered the identification of associated species and the understanding of the distribution and living conditions of this plant. Objective. To develop a model of geographical and potential distribution of mortiño, quantify plant diversity, and analyze the associated species, along with the uses and significance of the species in its ecological context. Materials and methods. The study was conducted in El Encano, Nariño-Colombia, during the year 2021. A participatory action research methodology was implemented, involving surveys, interviews, field visits with the community, and participatory workshops. For the development of distribution maps, ArcGIS 10.5 and MaxEnt 3.4.4 software’s were used. Biological diversity indices, such as Shannon-Weiner and Simpson, along with the importance value, were determined to evaluate species richness. Results. The community emphasizes the use of mortiño in food and traditional medicine. Twenty-one associated species were identified, with the fern (Blechnum loxense Kunth) being the most important. The distribution of V. floribundum was linked to favorable climatic conditions, with temperatures ranging 8 and 16 °C and an altitudinal gradient between 2800 to 3200 meters above sea level. Conclusions. The study identified two suitable ecosystems for mortiño: the high Andean Forest and the páramo. The importance value index highlights the fern as the most representative species associated with mortiño, providing valuable information for the conservation and sustainable management of these ecosystems in the region.

Given the gaps detected in the national engineering practice, a methodology is proposed to integrate the effects of climate change in the design of coastal and port infrastructure. The methodology considers four stages, namely: 1) selection of climatic drivers on a global scale, 2) processing of climatic drivers on a regional scale, 3) processing of design variables on a local scale and 4) application in different areas of infrastructure design. The methodology integrates the calculation of oceanographic variables (e.g. atmospheric pressure, wind, waves, astronomical tide, meteorological tide and sea level rise) in a flow diagram that can interact with other design variables, such as earthquakes and tsunamis. Examples are presented on calculations of port operational downtime, extreme sea levels on beaches, wave overtopping of maritime works and beach erosion. We encourage state agencies to develop stages 1) and 2), providing open access to stakeholders involved in the design of coastal and port infrastructure.

Ante las brechas detectadas en la práctica de la ingeniería nacional, se propone una metodología para integrar los efectos del cambio climático en el diseño de infraestructura costera y portuaria. La metodología considera cuatro etapas: 1) selección de forzantes climáticos a escala global, 2) procesamiento de forzantes climáticos a escala regional, 3) procesamiento de variables de diseño a escala local y 4) aplicación en diferentes ámbitos del diseño de infraestructura. La metodología integra el cálculo de variables oceanográficas (e.g. presión atmosférica, viento, oleaje, marea astronómica, marea meteorológica y aumento del nivel del mar) en un diagrama de flujo que puede interactuar con otras variables de diseño, como los sismos y tsunamis. Se presentan ejemplos sobre cálculos de operatividad portuaria, nivel del mar extremo en playas, sobrepaso de obras marítimas y erosión de playas. Proponemos que el estado desarrolle las etapas 1) y 2), dando acceso libre a los actores que participan en el diseño de infraestructura costera y portuaria.

Resumen En este artículo examinamos la incidencia de la escorrentía superficial en la visibilidad, preservación y distribución espacial de fragmentos cerámicos prehispánicos (ca. 100-1.535 d.C.) en abanicos aluviales de la Sierra de Quilmes (Noroeste Argentino), para evaluar la validez de patrones espaciales de ocupación establecidos en parte en base a ellos. Se prospectó uniendo ladera-piedemonte-fondo del valle con recolección de superficie, se realizaron sondeos y los lugares arqueológicos documentados se representaron cronológicamente diferenciados en mapas geomorfológico e hidrográfico. Finalmente se analizaron macroscópicamente trazas de arrastre hídrico en los fragmentos cerámicos. Los resultados evidenciaron que los tiestos son más frecuentes en las partes proximales y distales de los abanicos, y disminuyen marcadamente en los sectores medios eliminados por escorrentía superficial y canalización a través de las cárcavas, luego de un corto recorrido. Sin embargo, las alteraciones formales por desplazamientos son uniformemente leves entre esos sectores, y hay correspondencia espacial y cronológico-estilística entre los conjuntos superficiales y subsuperficiales. Consecuentemente, la distribución cerámica refleja la estructuración espacial arqueológica a escalas de localidad y microregión, aún bajo condiciones de erosión / sedimentación hídrica y eólica espacialmente diferenciadas favorecidas por la aridez, diferencias de pendientes y de cobertura vegetal.

Abstract In this article we examine the effects of surficial runoff on the visibility, preservation and spatial distribution of pre-Hispanic pottery sherds (ca. 100-1.535 a.C.) in alluvial fans of the Sierra de Quilmes (Northwest of Argentina) to evaluate the validity of spatial patterns of occupation based in part on them. Archaeological surveys across the slope-foothill-bottom of the valley with surface collection and pits were made. Archaeological places were located and chronologically differentiated in geomorphological and hydrological maps. Finally, traces of hydric displacement in the ceramic fragments were macroscopically analyzed. The results show, that pottery sherds were mainly found in the proximal and distal parts of the fans, but they markedly decrease in the middle sectors, eliminated by runoff and channeled through the gullies after a short distance displacement. However, formal modifications of the sherds due to displacement are uniformly slight in all three sectors, and, importantly, there are spatial and chronological-stylistic correspondences between surface and pit assemblages. Consequently, the pottery distribution reflects the archaeological spatial structure at local and microregional scales, even under spatially differentiated water and wind erosion / sedimentation, favored by aridity, differences in slopes and vegetation cover.