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1.
Mar Pollut Bull ; 206: 116714, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39002217

RESUMO

The northern shores of the Strait of Hormuz constitute one of the most diverse shorelines in the Persian Gulf, characterized by both utility and environmental richness. Situated in the Qeshm channel, which hosts the largest mangrove habitat, major industries, and commercial port, these shores are subject to the occurrence of oil spills, posing potential substantial harm. This study employs General NOAA Operational Modeling Environment (GNOME) and numerical modeling to assess the potential risks to shorelines from hypothetical oil spills, considering the distinctive features of the shores and their environmental sensitivity. The results indicate that high-risk levels are not excessively prevalent overall and are confined to approximately 24 km. The shape of the channel and hydrodynamic conditions highlight the eastern sector of the Bandar Abbas urban area as particularly susceptible to oil spill entrapment. The findings indicate that high-risk areas are predominantly located away from industrial-oil shores and primarily consist of muddy shores. Therefore, internal strategies of Oil Spill Contingency Plan (OSCP) of companies are deemed insufficient and necessitate comprehensive planning initiatives.

2.
Sci Rep ; 14(1): 13002, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844510

RESUMO

Monitoring sandy shoreline evolution from years to decades is critical to understand the past and predict the future of our coasts. Optical satellite imagery can now infer such datasets globally, but sometimes with large uncertainties, poor spatial resolution, and thus debatable outcomes. Here we validate and analyse satellite-derived-shoreline positions (1984-2021) along the Atlantic coast of Europe using a moving-averaged approach based on coastline characteristics, indicating conservative uncertainties of long-term trends around 0.4 m/year and a potential bias towards accretion. We show that west-facing open coasts are more prone to long-term erosion, whereas relatively closed coasts favor accretion, although most of computed trends fall within the range of uncertainty. Interannual shoreline variability is influenced by regionally dominant atmospheric climate indices. Quasi-straight open coastlines typically show the strongest and more alongshore-uniform links, while embayed coastlines, especially those not exposed to the dominant wave climate, show weaker and more variable correlation with the indices. Our results provide a spatial continuum between previous local-scale studies, while emphasizing the necessity to further reduce satellite-derived shoreline trend uncertainties. They also call for applications based on a relevant averaging approach and the inclusion of coastal setting parameters to unravel the forcing-response spectrum of sandy shorelines globally.

3.
Conserv Biol ; : e14301, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801276

RESUMO

People often modify the shoreline to mitigate erosion and protect property from storm impacts. The 2 main approaches to modification are gray infrastructure (e.g., bulkheads and seawalls) and natural or green infrastructure (NI) (e.g., living shorelines). Gray infrastructure is still more often used for coastal protection than NI, despite having more detrimental effects on ecosystem parameters, such as biodiversity. We assessed the impact of gray infrastructure on biodiversity and whether the adoption of NI can mitigate its loss. We examined the literature to quantify the relationship of gray infrastructure and NI to biodiversity and developed a model with temporal geospatial data on ecosystem distribution and shoreline modification to project future shoreline modification for our study location, coastal Georgia (United States). We applied the literature-derived empirical relationships of infrastructure effects on biodiversity to the shoreline modification projections to predict change in biodiversity under different NI versus gray infrastructure scenarios. For our study area, which is dominated by marshes and use of gray infrastructure, when just under half of all new coastal infrastructure was to be NI, previous losses of biodiversity from gray infrastructure could be mitigated by 2100 (net change of biodiversity of +0.14%, 95% confidence interval -0.10% to +0.39%). As biodiversity continues to decline from human impacts, it is increasingly imperative to minimize negative impacts when possible. We therefore suggest policy and the permitting process be changed to promote the adoption of NI.


Cuantificación del impacto de la futura modificación de la costa sobre la biodiversidad en un estudio de caso de la costa de Georgia, Estados Unidos Resumen Las personas modifican con frecuencia la costa para mitigar la erosión o proteger su propiedad del impacto de las tormentas. Los dos enfoques principales para la modificación son la infraestructura gris (p. ej.: mamparos y malecones) y la infraestructura verde o natural (IN) (p.ej.: costas vivientes). La infraestructura gris es más común que la IN, a pesar de que tiene efectos dañinos sobre los parámetros ambientales, como la biodiversidad. Evaluamos el impacto de la infraestructura gris sobre la biodiversidad y si la adopción de la IN puede mitigar su pérdida. Analizamos la literatura para cuantificar la relación de la infraestructura gris y la IN con la biodiversidad. También desarrollamos un modelo con datos geoespaciales temporales sobre la distribución de los ecosistemas y la modificación de la costa para proyectar la modificación costera en el futuro en nuestra localidad de estudio: la costa de Georgia, Estados Unidos. Aplicamos las relaciones empíricas derivadas de la literatura de los efectos de la infraestructura sobre la biodiversidad a las proyecciones de modificación de la costa para predecir el cambio en la biodiversidad bajo diferentes escenarios de infraestructura gris versus IN. En nuestra área de estudio, que está dominada por marismas y usa infraestructura gris, cuando un poco menos de la mitad de toda la infraestructura costera nueva debería ser IN, las pérdidas previas de biodiversidad a partir de la infraestructura gris podrían mitigarse para 2100 (cambio neto de la biodiversidad de +0.14%, 95% intervalo de confianza ­0.10% a +0.39%). Conforme la biodiversidad siga en declive por el impacto humano, cada vez es más imperativo minimizar el impacto negativo cuando sea posible. Por lo tanto, sugerimos que se modifiquen las políticas y el proceso de permisos para promover la adopción de la IN.

4.
Mar Pollut Bull ; 203: 116483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38776643

RESUMO

Thorough deliberation is necessary to safeguard the tropical urban streams near the shoreline from human interference, as it is becoming a notable environmental danger. Consequently, an in-depth study was carried out on a significant urban waterway located on the southern seashore of Bangladesh, which is positioned in the Bengal delta, renowned as the largest delta in the globe. The current investigation assesses the potential health hazards associated with trace metals (Hg, Cu, As, Pb, Ni, Zn, Cd, Cr, Fe, and Mn) and uses chemometric analysis to determine where they originate. Likewise geochemical methods are used to analyze the levels of trace metal enrichment and pollution in the sediments of the river. Almost all of the elements' mean concentrations were observed to be within the standard limits. The findings not only demonstrate the extent of trace metal contamination but also the health threats that it poses to the public (male, female, and children) by polluting the sediment. For all age groups of people, the hazard index was <1, suggesting there was no non-carcinogenic threat. Regardless of age and sex, exposure occurred in descending order: ingestion > dermal > inhalation. Total carcinogenic risk (TCR) values for males, females, and children were 1.45E-05, 1.56E-05, and 1.34E-04, respectively, recommending that children are at greater vulnerability than adults. The geochemical approach and chemometric analysis corroborate the human-induced impact of trace metal loading in the sediment of the waterway, which is predominantly caused by the oil industry, domestic garbage, and untreated waste discharge.


Assuntos
Monitoramento Ambiental , Metais , Poluentes Químicos da Água , Humanos , Medição de Risco , Poluentes Químicos da Água/análise , Bangladesh , Metais/análise , Feminino , Masculino , Sedimentos Geológicos/química , Criança , Metais Pesados/análise
5.
Conserv Biol ; 38(4): e14263, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38578170

RESUMO

Although human-made barriers to animal movement are ubiquitous across many types of ecosystems, the science behind these barriers and how to ameliorate their effects lags far behind in marine environments compared with terrestrial and freshwater realms. Using juvenile sawfish in an Australian nursery habitat as a model system, we aimed to assess the effects of a major anthropogenic development on the movement behavior of coastal species. We compared catch rates and movement behavior (via acoustic telemetry) of juvenile green sawfish (Pristis zijsron) before and after a major coastal structure was built in an important nursery habitat. Acoustic tracking and catch data showed that the development did not affect levels of sawfish recruitment in the nursery, but it did constrain movements of juveniles moving throughout the nursery, demonstrating the reluctance of shoreline-associated species to travel around large or unfamiliar coastal structures. Given the current lack of information on human-made movement barriers in the marine environment, these findings highlight the need for further research in this area, and we propose the development of and experimentation with marine animal crossings as an important area of emerging research.


Efectos del desarrollo costero sobre los movimientos del pez sierra y la necesidad de soluciones para el cruce de animales marinos Resumen Mientras que las barreras construidas por humanos que limitan el movimiento de animales son ubicuas en muchos tipos de ecosistemas, la ciencia que sustenta estas barreras y la reducción de sus impactos está muy retrasada en ambientes marinos en comparación con medios terrestres y dulceacuícolas. Utilizando peces sierra juveniles en un hábitat de vivero australiano como sistema modelo, intentamos evaluar los efectos de un importante desarrollo antropogénico sobre el comportamiento de especies costeras. Comparamos las tasas de captura y el comportamiento de movimiento (mediante telemetría acústica) de peces sierra verdes juveniles (Pristis zijsron) antes y después de que se construyera infraestructura costera en un importante hábitat de vivero. El seguimiento acústico y los datos de captura mostraron que el desarrollo no afectó los niveles de reclutamiento de pez sierra en el vivero, pero sí restringió los movimientos de los juveniles desplazándose por el vivero, lo cual demuestra la renuencia de las especies asociadas a la costa a viajar alrededor de estructuras costeras grandes o desconocidas. Dada la actual falta de información sobre las barreras de movimiento creadas por el hombre en el medio marino, estos hallazgos destacan la necesidad de realizar más investigaciones en esta campo, y proponemos el desarrollo y la experimentación con cruces para animales marinos como un área importante de investigación emergente.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Conservação dos Recursos Naturais/métodos , Alismatales/fisiologia , Austrália , Movimento
6.
Sci Total Environ ; 926: 171690, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38513846

RESUMO

Mangrove shoreline retreat or advance is a natural process in a mangrove delta. However, due to various natural and anthropogenic stressors, mangrove shoreline retreat is the second largest cause of mangrove loss globally. It is important to understand the scale at which mangrove shoreline changes are causing biophysical changes along the mangrove shorelines and, in turn, understand if certain biophysical characteristics can explain the changes along the shoreline. This will help identify the response of mangroves to shoreline changes. Videography and spatial mapping were used to study temporarily and permanently changing mangrove shorelines in the Sundarbans, the largest mangrove forest in the world (~10,000 km2), located in India and Bangladesh. Data was collected along a ~ 239 km shoreline at 54 sites. 36.4 % of all the studied shorelines were experiencing major retreat, 63.8 % and 27.2 % of all (major and minor) retreating areas had 1-25 % and > 25 % dead trees. The biophysical characteristics statistically (P < 0.0001) associated with retreating mangrove shorelines were - cliff-type shoreline profiles, number of dead trees, and absence of stream and grass, with shoreline profiles as the strongest predictor of shoreline retreat. Moreover, 68.7 % and 73 % of historically retreating shorelines had a cliff-type shoreline profile and Excoecaria agallocha as the dominating species, respectively. Moreover, due to the strong correlation between historical changes and current shoreline types, it was concluded that characteristics along the shoreline are partly a product of historical shoreline transitions. Thus, the present status of the shoreline can not only predict the history of the shoreline but can also give insights into the future biophysical changes in the mangrove forests.


Assuntos
Árvores , Áreas Alagadas , Bangladesh , Índia , Previsões , Ecossistema
7.
Mar Pollut Bull ; 200: 116096, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38340372

RESUMO

Coastal sprawl is among the main drivers of global degradation of shallow marine ecosystems. Among artificial substrates, quarry rock can have faster recruitment of benthic organisms compared to traditional concrete, which is more versatile for construction. However, the factors driving these differences are poorly understood. In this context, this study was designed to compare the intertidal and subtidal benthic and epibenthic assemblages on concrete and artificial basalt boulders in six locations of Madeira Island (northeastern Atlantic, Portugal). To assess the size of the habitat, the shorelines in the study area were quantified using satellite images, resulting in >34 % of the south coast of Madeira being artificial. Benthic assemblages differed primarily between locations and secondarily substrates. Generally, assemblages differed between substrates in the subtidal, with lower biomass and abundance in concrete than basalt. We conclude that these differences are not related to chemical effects (e.g., heavy metals) but instead to a higher detachment rate of calcareous biocrusts from concrete, as surface abrasion is faster in concrete than basalt. Consequently, surface integrity emerges as a factor of ecological significance in coastal constructions. This study advances knowledge on the impact and ecology of artificial shorelines, providing a baseline for future research towards ecological criteria for coastal protection and management.


Assuntos
Ecossistema , Silicatos , Biomassa , Portugal
8.
Mar Pollut Bull ; 200: 116089, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377861

RESUMO

This investigation analyzed shoreline evolution along India's Digha Coast from 1992 to 2022, using multispectral Landsat satellite images and the Digital Shoreline Analysis System (DSAS). Methods included identifying zones and transects, shoreline extraction, and applying spatial statistical techniques. The study area, divided into five zones with 587 transects, enabled both short- and long-term analysis. Key findings indicate that the mean long-term rate of shoreline change is -0.54 m per year, with 70.70 % of transects experiencing erosion and 29.30 % accretion. Notably, Zone V had the highest accretion rate (8.55 m/year), while Zone III faced the most erosion (-7.47 m/year). Short-term analysis from 1997 to 2017 indicated significant erosion, contrasting with accretion during 1992-1997 and 2017-2022. Particularly, Zones II, III, and IV underwent major erosion, especially from 1997 to 2002. The study underscores the need for continuous shoreline management strategies and demonstrates geospatial technology's effectiveness in capturing coastal landscape changes.


Assuntos
Efeitos Antropogênicos , Monitoramento Ambiental , Monitoramento Ambiental/métodos , Índia
9.
Sci Total Environ ; 919: 170830, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340829

RESUMO

It is imperative to assess coastal vulnerability to safeguard coastal areas against extreme events and sea-level rise. In the Niger Delta region, coastal vulnerability index assessment in the past focused on open-access parameters without comparing the open-access parameters, especially coastal elevation and shoreline change. This sensitivity to the shoreline method and open-access coastal elevation limits the information for the planning of coastal adaptation. The area under investigation is the Niger Delta, which is distinguished by its low-lying coastal plains and substantial ecological and economic significance. In light of the selected parameters, Sentinel-1 GRD images from 2015 to 2022 during high tidal conditions were used to delineate the shoreline position and change rate. Also, different open-access DEMs were used to derive the coastal elevation using the Geographic Information System (GIS) approach. The study employs 5 parameters, such as shorelines obtained from Sentinel-1 SAR images and several Digital Elevation Models (DEMs), geomorphology, mean sea level rise, significant wave height, and mean tide range, in conjunction with the initial Coastal Vulnerability Index (CVI) approach. The study reveals that the type of DEM used significantly influences the coastal elevation ranking and, subsequently, the CVI. Differences in shoreline change rate estimation methods (EPR and LRR) also impact the vulnerability rankings but to a lesser extent. The findings highlight that 40.1% to 58.9% of the Niger Delta coastline is highly or very highly vulnerable to sea-level rise, depending on the shoreline change rate or DEM used. The study underscores the potential of using CVI methods with open-access data in data-poor countries for identifying vulnerable coastal areas that may need protection or adaptation. Lastly, it points out the need for higher resolution DEMs.

10.
Environ Monit Assess ; 196(2): 199, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267789

RESUMO

The Muriganga River, also known as channel creek, underwent morphological changes often since it is an alluvial as well as a tidal river. The present study analyses the morphological changes in the Muriganga River and its islands with the help of the Remote Sensing and Geographical Information System (GIS) and digital shoreline analysis tool (DSAS 5.0). Moreover, the computation of morphological changes was also performed on two islands, i.e. Sagar and Ghoramara, which are situated just outside the river reach. Eight cloud-free satellite images of Landsat MSS (1972-1980), Landsat TM (1988-2011) and Landsat OLI (2017-2021) have been used to investigate the river shoreline shifting and island dynamics of the Muriganga River resulted from the erosion-accretion process during the last 49 years. For the short-term study, the erosion-accretion rates are derived from one Landsat image to the next, whereas for long-term analysis, the erosion-accretion rates are estimated based on the difference between 1972 as the reference image and the succeeding images. Short-term and long-term analysis shows that the average rate of erosion is more than that of accretion in Muriganga River. It is also found that the areas of Sagar, Ghoramara, Mousuni and Pushpa islands are shrinking continuously, whereas the Niogi and Basit islands are expanding enormously. These may indicate that the shoreline erosion results in widening the river and the eroded materials are accumulated in Niogi and Basit islands. The results suggest that there is an urge for a better coastal management strategy for the erosion control scheme. This study also helps in gaining knowledge of maintaining the navigability in the Muriganga River.


Assuntos
Monitoramento Ambiental , Rios , Sistemas de Informação Geográfica
11.
Sci Total Environ ; 917: 170230, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38278234

RESUMO

This research comprehensively assesses the aftermath of Cyclonic Storm Mocha, focusing on the coastal zones of Rakhine State and the Chittagong Division, spanning Myanmar and Bangladesh. The investigation emphasizes the impacts on coastal ecology, shoreline dynamics, flooding patterns, and meteorological variations. Employed were multiple vegetation indices-Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), Modified Vegetation Condition Index (mVCI), Disaster Vegetation Damage Index (DVDI), and Fractional Vegetation Cover (FVC)-to evaluate ecological consequences. The Digital Shoreline Assessment System (DSAS) aided in determining shoreline alterations pre- and post-cyclone. Soil exposure and flood extents were scrutinized using the Bare Soil Index (BSI) and Modified Normalized Difference Water Index (MNDWI), respectively. Additionally, the study encompassed an analysis of microclimatic variables, comparing meteorological data across pre- and post-cyclone periods. Findings indicate significant ecological impacts: an estimated 8985.46 km2 of dense vegetation (NDVI >0.6) was adversely affected. Post-cyclone, there was a discernible reduction in EVI values. The mean mVCI shifted negatively from -0.18 to -0.33, and the mean FVC decreased from 0.39 to 0.33. The DVDI underscored considerable vegetation damage in various areas, underscoring the cyclone's extensive impact. Meteorological analysis revealed a 245 % increase in rainfall (20.22 mm on May 14, 2023 compared to the May average of 5.86 mm), and significant increases in relative humidity (14 %) and wind speed (205 %). Erosion was observed along 74.60 % of the studied shoreline. These insights are pivotal for developing comprehensive strategies aimed at the rehabilitation and conservation of critical coastal ecosystems. They provide vital data for emergency response initiatives and offer resources for entities engaged in enhancing coastal resilience and protecting local community livelihoods.

12.
Sci Total Environ ; 917: 170444, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38290675

RESUMO

Lakes, as vital components of the Earth's ecosystem with crucial roles in global biogeochemical cycles, are experiencing pervasive and irreparable worldwide losses due to natural factors and intensive anthropogenic interferences. In this study, we investigated the long-term dynamic patterns of the Tonle Sap Lake, the largest freshwater lake in the Mekong River Basin, using a series of hydrological data and remote sensing images between 2000 and 2020. Our findings revealed a significant decline in the annual average water level of the lake by approximately 2.1 m over 20 years, accompanied by an annual average reduction in surface area of about 1400 km2. The Tonle Sap Lake exhibited episodic declines in water level and surface area, characterized by the absence of flooding during the flood season and increasing aridity during the dry season. Furthermore, the shoreline of the lake has significantly advanced towards the lake in the northwestern and southern regions during the dry season, primarily due to sedimentation-induced shallowing of the lake edge depth and decreased water levels. In contrast, lake shorelines in the eastern region remained relatively stable due to the constructed embankments for the protection of the cultivated farmland. While the seasonal fluctuations of the Tonle Sap Lake are regulated by regional precipitation in the Mekong River Basin, the prolonged shrinking of the lake can be mainly ascribed to intensive anthropogenic activities. The interception of dams along the upper Mekong River has resulted in a decrease in the inflow to Tonle Sap Lake, exacerbating its shrinkage. Moreover, there are minor impacts from agricultural land expansion and irrigation on the lake. This study highlights the driving forces behind the evolution of Tonle Sap Lake, providing valuable information for lake managers to develop strategies aimed at conserving and restoring the ecological integrity of the Tonle Sap Lake.

13.
J Environ Manage ; 351: 119622, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042079

RESUMO

Vegetation is a critical boundary condition for the stability of coastal dunes. Globally, vegetation cover is increasing on the coast with many dunes being stabilised in the past decades. This pattern is driven by site-specific (e.g., coastal management) and global (e.g., climatic changes) factors. This study examines changes in dune vegetation during the past six decades at the regional scale along the southeast coast of Australia to understand the relative importance of the climate and human interventions in vegetation cover change. A total area of >31,000 ha, comprising 53% of the open coast of Victoria was studied. Since the 1960's, a general trend of dune stabilisation and coastal greening has occurred with total vegetation cover increasing from 61% to 84% coverage until 2020. At the regional scale, the increase in vegetation cover has been primarily driven by both climatic-related drivers, such as rising temperature, elevating CO2 concentrations and declining windiness, and state-wide coastal management interventions (e.g., marram grass planting, fencing, fire control, grazing removal). The only areas where there was a decline in total area of vegetation was where substantial coastal recession had occurred. The decrease in vegetation is a result of a loss of land area rather than a loss of plant biomass over the dunefields. Therefore, it is considered that the overall decadal changes in both climate and coastal management are forcing the dunes toward a more stabilised state at the regional scale. At the same time, compelling local drivers (e.g., storms and local sediment deficiency) can be the most crucial factor to regulate vegetation change and shift dune mobility at the site-specific scale.


Assuntos
Ecossistema , Plantas , Humanos , Vitória , Biomassa
14.
Mar Pollut Bull ; 198: 115905, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38101058

RESUMO

Shoreline surveys are a common approach for documenting loads of marine macrodebris (≥ 2.5 cm). When surveys are conducted repeatedly over time and space, patterns in source, abundance, geographic distribution, and composition can be detected. Yet to realize their full potential, monitoring programs that rely on surveys must grapple with high variability in debris abundance, and appropriately manage uncertainty when reporting estimates of debris quantity. A potentially important source of bias in estimating debris loads from shoreline monitoring datasets is variability in debris detection rates. With this in mind, we conducted field experiments using common strip-transect marine debris survey protocols, designed to test detection of macrodebris. We quantified how protocol, shoreline, and debris characteristics influence the detectability of marine macrodebris. Detection rates varied according to debris distance from observer (0-5 m), number of observers, debris characteristics (size, color), and shoreline substrate. Our results highlight considerations for monitoring program design. Comparisons across datasets should be approached cautiously given differences in survey protocols and sources of bias that may affect debris density estimates should be quantified and addressed. We hope these results will inform marine debris monitoring efforts that are optimized for intended data use and impact.


Assuntos
Monitoramento Ambiental , Resíduos , Resíduos/análise , Monitoramento Ambiental/métodos , Inquéritos e Questionários , Plásticos
15.
Sensors (Basel) ; 23(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38067708

RESUMO

Barrier islands are vital dynamic landforms that not only host ecological resources but often protect coastal ecosystems from storm damage. The Waisanding Barrier (WSDB) in Taiwan has suffered from continuous beach erosion in recent decades. In this study, we developed a SiamUnet network compared to three basic DeepUnet networks with different image sizes to effectively detect barrier waterlines from 207 high-resolution satellite images. The evolution of the barrier waterline shape is obtained to present two special morphologic changes at the southern end and the evolution of the entire waterline. The time periods of separation of the southern end from the main WSDB are determined and discussed. We also show that the southern L-shaped end has occurred recently from the end of 2017 until 2021. The length of the L-shaped end gradually decreases during the summer, but gradually increases during the winter. The L-shaped end obviously has a seasonal and jagged change. The attenuation rate of the land area is analyzed as -0.344 km2/year. We also explore two factors that affect the analysis results, which are the number of valid images selected and the deviation threshold from the mean sea level.

16.
Ecol Restor ; 41(2-3): 84-98, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37990651

RESUMO

As salt marsh habitats face challenges due to sea level rise, storm events, and coastal development, there is an effort to use nature-based approaches such as living shorelines to enhance salt marshes and provide coastal protection. A living shoreline restoration and seasonal monitoring was conducted between July 2016 and October 2018 at an eroding salt marsh on Martha's Vineyard, Massachusetts, Northeastern USA to assess changes in two essential ecosystem services: shoreline stabilization and nitrogen removal. Neither the living shoreline nor unaltered sites demonstrated significant sediment deposition at the marsh edge or on the marsh platform between 2017 and 2018. While we expected nitrogen removal via denitrification to improve at the living shoreline sites over time as abiotic and biotic conditions became more favorable, we found limited support for this hypothesis. We found higher rates of denitrification enzyme activity (DEA) at the living shoreline sites when compared to unaltered sites, but these rates did not increase over time. This study also provides a qualitative assessment of our living shoreline structural integrity through the years, particularly following storm events that greatly challenged our restoration efforts. We demonstrate that living shorelines fortified solely with natural materials may not be the most effective approach to maintain these ecosystem services for Northeastern USA salt marshes exposed to intense northeasterly storms. We suggest the restoration of salt marshes to improve major functions be a priority among managers and restoration practitioners. Initiatives promoting the use of nature-based restoration solution where environmental conditions permit should be encouraged.

17.
Heliyon ; 9(9): e20001, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809942

RESUMO

Coastal regions are of extraordinary significance for the financial and welfare of human communities. Unfortunately, coastal regions are naturally pressured by anthropogenic activities that increase their vulnerability. Hence, there is a drastic need to monitor coastal changes to protect and manage them sustainably. Since Kuwait's coast is inhabited by about 94% of the inhabitants and most of the metropolitan area and the urgent need for sustainable planning and management of Kuwait's coast, this paper aims to analyze the historical changes rate of Kuwait's coast and Kuwait islands over 40 years from 1980 to 2020 and to predict the future changes of the shoreline in 2035 using EPR model. The results show that the highest accretion rate of the shoreline is 32.79 m/year, while the lowest erosion rate is -23.45 m/year. EPR of the islands revealed a fluctuation between erosion and deposition at each island. The future predicted shoreline changes were also mapped for the shoreline and islands.

18.
Sci Total Environ ; 904: 166310, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37586521

RESUMO

Under the influence of anthropogenic climate change, hazardous climate and weather events are increasing in frequency and severity, with wide-ranging impacts across ecosystems and landscapes, especially fragile and dynamic coastal zones. The presented multi-model chain approach combines ocean hydrodynamics, wave fields, and shoreline extraction models to build a Bayesian Network-based coastal risk assessment model for the future analysis of shoreline evolution and seawater quality (i.e., suspended particulate matter, diffuse attenuation of light). In particular, the model was designed around a baseline scenario exploiting historical shoreline and oceanographic data within the 2015-2017 timeframe. Shoreline erosion and water quality changes along the coastal area of the Metropolitan city of Venice were evaluated for 2021-2050, under the RCP8.5 future scenario. The results showed a destabilizing trend in both shoreline evolution and seawater quality under the selected climate change scenario. Specifically, after a stable period (2021-2030), the shoreline will be affected by periods of erosion (2031-2040) and then accretion (2041-2050), with a simultaneous decrease in seawater quality in terms of higher turbidity. The decadal analysis and sensitivity evaluation of the input variables demonstrates a strong influence of oceanographic variables on the assessed endpoints, highlighting how the factors are strongly connected. The integration of regional and global climate models with Machine Learning and satellite imagery within the proposed multi-model chain represents an innovative update on state-of-the-art techniques. The validated outputs represent a good promise for better understanding the varying impacts due to future climate change conditions (e.g., wind, wave, tide, and sea-level). Moreover, the flexibility of the approach allows for the quick integration of climate and multi-risk data as it becomes available, and would represent a useful tool for forward-looking coastal risk management for decision-makers.

19.
Ecol Evol ; 13(7): e10268, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37424934

RESUMO

Lakes and their shoreline vegetation are rich in biodiversity and provide multiple functions and habitats for fauna and flora. Humans are attracted by the scenic beauty of these ecosystems and the possibilities for recreational activities they offer. However, the use of lakes for recreational activities can lead to disturbance of vegetation, threatening the integrity and functionality of shoreline areas. Recent literature reviews revealed that impacts of the seemingly harmless activities bathing and lingering on the shore on lakeshore vegetation are poorly understood. In this study, we analysed the effects of shoreline use connected with bathing on the structure, composition and diversity of lakeshore vegetation. Vegetation relevés were recorded in 10 bathing and 10 adjacent control sites in the nature park 'Dahme-Heideseen' (Brandenburg, Germany). In addition visitor counts were performed. The species composition and the cover of herbaceous and shrub vegetation differed between bathing and control sites, but all sites had a high percentage of plant species not typical for the community. The vegetation parameters did not correlate with visitor counts. The results indicate that the present visitor intensity in the nature park does not impact the vegetation severely.

20.
Mar Pollut Bull ; 193: 115234, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37399736

RESUMO

Oil deposited on shoreline substrates has serious adverse effects on the coastal environment and can persist for a long time. In this study, a green and effective microemulsion (ME) derived from vegetable oil was developed as a washing fluid to remove stranded oil from beach sand. The pseudo-ternary phase diagrams of the castor oil/water (without or without NaCl)/Triton X-100/ethanol were constructed to determine ME regions, and they also demonstrated that the phase behaviors of ME systems were almost independent of salinity. ME-A and ME-B exhibited high oil removal performance, low surfactant residues, and economic benefits, which were determined to be the W/O microstructure. Under optimal operation conditions, the oil removal efficiencies for both ME systems were 84.3 % and 86.8 %, respectively. Moreover, the reusability evaluation showed that the ME system still had over 70 % oil removal rates, even though it was used six times, implying its sustainability and reliability.


Assuntos
Areia , Tensoativos , Reprodutibilidade dos Testes , Emulsões/química , Tensoativos/química , Octoxinol
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