Anthropocene Coasts最新文献

A sedimentation issue in the estuary of Porong induced by Lapindo hot mud discharge had caused a significant morphological alteration. This study aims to determine the geomorphological evolution in the Porong Estuary and the geochronological formation of Lusi Island. This study employed a numerical modeling approach, consisting of flow and sediment transport modeling modules (Delft3D-FLOW and Delft3D-SED), with a curvilinear grid resolution of 25–50 m over a 5 × 6 km domain. A satellite imagery processing was also performed using multitemporal Landsat data (2000–2024) analyzed using the Modified Normalized Difference Water Index (MNDWI), followed by binary classification and vector digitization. The results show that sediment accumulation of ± 0.06 m in 15 days, increasing to over 1 m after four years (MORFAC 96), with land expansion confirmed by satellite data from 6.29 hectares in 2000 to 147.86 hectares in 2024. Of particular concern, the increasing sediment thickness from 0.0026 m to 0.38 m over a 14-year equivalent simulation suggests a sustained process of geomorphological development. The findings of this study emphasize significant sedimentation trends and the dynamics of the estuarine environment in the Porong Estuary. It is, therefore, crucial to implement coastal hazard mitigation strategies, effective land use planning, and environmental monitoring to minimize further environmental degradation resulting from excessive sedimentation.

Accurate oceanic weather forecasting plays a crucial role in various marine applications, from wave energy resource assessment to the establishment of operational safety limits for maritime activities. Among the key oceanic parameters, significant wave height is of particular importance due to its direct impact on marine operations. Traditional numerical simulations, while effective, require precise boundary conditions and substantial computational resources, often leading to long processing times. In contrast, deep learning approaches, leveraging powerful neural networks, have gained increasing attention for their ability to generalize and model complex, nonlinear relationships in data. However, current deep learning-based predictive models still face challenges regarding prediction accuracy and generalizability, particularly over extended forecast periods. To address these challenges, we propose an innovative predictive framework, VMD-Informer, which combines deep learning techniques with signal processing methods to improve the accuracy of significant wave height predictions over long forecasting horizons. The framework utilizes the Variational Mode Decomposition (VMD) method to decompose wave signal data during the preprocessing stage, enhancing both processing efficiency and prediction accuracy. The model construction incorporates the Informer model, which is specifically designed to ensure high accuracy across multi-step long-term time series predictions. Using data from NOAA's global buoy station 46,078, covering the years 2018–2019, our experiments demonstrate that the VMD-Informer model outperforms traditional machine learning models, particularly in predicting significant wave height for longer forecast intervals. These results highlight the potential of the VMD-Informer approach for advancing the accuracy of long-term oceanic weather predictions, providing valuable insights for marine forecasting systems.

High-level pond aquaculture, as a typical aquaculture model along the South China coast, poses potential threats to coastal ecosystems due to beach topographic changes induced by its tailwater discharge. Supported by drone technology, this study employed a combined method of DJI Matrice 300 RTK UAV LiDAR surveying and ground GNSS RTK measurements to collect data from the beach area affected by high-level pond tailwater discharge in northern Longhaitian, eastern Leizhou Peninsula. The study aims to investigate the impact of high-level pond tailwater discharge on beach topography using DSM generated from UAV LiDAR data. The results show: (1) By verifying the accuracy of UAV LiDAR data (RMSE of 8.05 cm, 99% confidence interval [6.59,8.09] cm), confirmed the reliability and applicability of UAV LiDAR for monitoring beach topography affected by high-level pond tailwater discharge, with credible measurement data; (2) The beach exhibits significant spatial differentiation characteristics: the beach berm is eroded by aquaculture tailwater, with the central beach berm completely eroded away; (3) Compared to unaffected profiles, those influenced by high-level pond tailwater discharge show greater elevation change ranges, with maximum erosion depths exceeding 4 m and maximum sedimentation thickness approaching 2 m. The affected beach area demonstrates berm erosion, sedimentation in erosion gullies, and scarp erosion in the southern section, with maximum scarp erosion reaching approximately 5 m. The combined effects of tides and aquaculture tailwater discharge are the primary factors causing these phenomena. These research findings can provide technical support for the quantitative assessment of beach topography changes induced by high-level pond tailwater discharge.

Mangrove forests possess significant ecological and aesthetic values. Investigating the spatial distribution characteristics of beach sediments in mangrove habitats and their relationships with hydrodynamic conditions and vegetation dynamics is crucial for sustaining the health and sustainability of mangrove ecosystems. This study aims to explore the spatial distribution characteristics of sediments in the mangrove beach of Xiashan Sea-viewing Promenade, Zhanjiang, and their relationship with hydrodynamics and mangrove vegetation. A total of 59 surface sediment samples were collected from 6 transects in the study area. The elevation of the sampling points, as well as wave and current data during the sampling period, were measured. The sediment transport trends of the 6 transects were also analyzed. The results show that the average grain size of surface sediments in the study area ranges from -0.75 to 5.15 φ; the average sorting coefficient is 1.26, indicating poor sediment sorting; the average skewness is 0.19, with positively skewed and extremely positively skewed sediments widely distributed in the study area; the kurtosis values range from 0.36 to 2.31, with an average of 1.14, and narrow kurtosis is observed on the seaward side of the southern and northern parts of the study area. The significant wave height in the study area ranges from 0.05 to 0.17 m, the wave period ranges from 1.44 to 3.38 s, and the current velocity ranges from 1.44 to 7.44 cm·s⁻¹. The surface sediment types include gravel, sand, silt, and clay, with sand being the most abundant, followed by silt, while gravel and clay are present in small amounts, with gravel only found in small quantities near the shore in the northern part of the study area. The sand content decreases from the shore to the sea, while the spatial distribution of silt shows the opposite trend. The clay content is relatively low, with a higher concentration in the seaward area. The wave action in the study area is significantly stronger than the current action, with the strongest hydrodynamic forces occurring during the early flood tide and late ebb tide, leading to an onshore sediment transport trend. This process can increase beach elevation and stability, which is beneficial for the growth and development of mangroves.

The impacts of climate change on marine fisheries are becoming increasingly evident; however, climate resilient fisheries management and policy making continues to be challenging. In the Arabian Peninsula Region (APR), productivity of the marine and coastal fisheries is largely impacted by climate change. The present study provides perspectives of the existing fisheries management plans of the APR with special emphasis on the Sultanate of Oman (SO) by conducting a comprehensive literature survey that includes primary research articles, academic theses, reports, governmental decisions and legislations and reputable websites. The study proposes future climate-adaptive management strategies for APR and SO, emphasizing the risk assessments, stakeholder collaboration by taking a transboundary approach. Fisheries management in the APR currently faces challenges of overfishing, habitat degradation, and climate change impacts, with each country employing unique approaches; regional cooperation and sharing best practices are deemed essential for long-term sustainability. Fisheries management in the SO, a critical part of the country's economy, includes measures such as licensing and seasonal closures; however, a climate-resilient framework for pelagic fisheries is lacking, which is creating an uncertainty in fisheries management the face of ongoing climate change. Effective climate-adaptive fisheries management in the SO necessitates risk assessments, stakeholder engagement, and cross-border collaborations. The APR as a whole requires integrated short- and long-term strategies for addressing climate change impacts on marine ecosystems and fisheries, with a focus on flexibility and local participation. The study recommends ecosystem-based fisheries management, which incorporates both biotic and abiotic elements, as well as regional evaluations and co-management solutions to mitigate the effects of climate change.

Research on the spatial and temporal distribution of shrimp mariculture can provide a reference for the optimization of the spatial distribution and sustainable development of the shrimp mariculture industry. In recent years, most of the domestic shrimp research focuses on biological characteristics, shrimp breeding, and environmental factors, with limited studies on the overall distribution patterns of large-scale marine shrimp farming.11 provinces along the coast of China were selected as the study area to investigate the spatial and temporal evolution characteristics of the four types of shrimp marine aquaculture production and their spatial differences in driving factors over the past 20 years. The results showed that: (1) The production and farming area of Litopenaeus vannamei (LV) were the highest among the four types of shrimp and increased exponentially over time. The farming area of the other three shrimp species showed a decreasing trend; (2) The farming centers of LV and Penaeus monodon (PM) are located in the southern regions, while those of Fenneropenaeus chinensis (FC) and Marsupenaeus japonicus (MJ) are in the northern regions. The farming centers of all four types of shrimp have shifted to varying degrees, with farming area being the main factor influencing the movement of these centers; (3) Regarding driving factors, wild catch, farming area, and extension personnel are the leading factors in the spatial differences in production, and the interaction between the factors ultimately led to spatial differences in shrimp production; (4) Comparison of different sea areas revealed that shrimp in the South China Sea region is mainly farmed in sea water, while the northern regions rely more on freshwater farming. The yield of shrimp per unit area in the South China Sea can reach up to 14 t/ha, which is significantly higher than that in the northern region; (5) Using the established regression model to predict the production and area of LV, its production and area in the next five years to maintain a sustained growth trend. The results can provide support for the formulation of relevant government policies, thus promoting the healthy development of shrimp mariculture.

Long-term morphological changes in beaches are crucial for developing and managing coastal zones and have significant implications for coastal disaster prevention and mitigation, as well as sustainable development of sandy shorelines under global climate change conditions. Pingtan Island, located on the west coast of the Taiwan Strait, about 40 km south of the Minjiang River Estuary, features a 70 km -long sandy shoreline, and its developmental history exhibits distinct phases. This study analyzes the spatio-temporal evolutionary characteristics of sandy shorelines on Pingtan Island over the past 35 years by utilizing continuous satellite imagery from 1990 to 2024 and the CoastSat global shoreline mapping tool. The primary controlling factors influencing the evolution of sandy shorelines are also identified in this study. The results indicate that (1) driven by variations in coastal dynamic conditions, the evolution of the sandy shoreline along Pingtan Island exhibits notable spatial differences, with erosion intensities significantly greater in the northern and eastern regions of the island than in the southeastern and southern areas. (2) The sandy shoreline of Pingtan Island demonstrates clear phased evolutionary characteristics: from 1990 to 2010, the shoreline generally experienced erosion, with a higher erosion rate observed from 1990 to 1999, followed by a deceleration in erosion from 2000 to 2010. After 2010, the shoreline tended toward stability, which was related to changes in sediment discharge in the Minjiang River estuary. (3) Following an adaptation period of 5–15 years after sediment discharge from adjacent rivers stabilized, a new dynamic equilibrium was established. However, this equilibrium was subsequently disrupted by intense human activities, leading to renewed oscillations of erosion and accretion along the sandy shoreline.

Wildwood and Cape May beaches in New Jersey are vital for ecological, recreational, and economic reasons. These areas support critical habitats and endangered species that depend on the unique sediment characteristics of the beaches. Economically, Cape May County tourism contributed $7.7 billion in 2023 to the local economy. This study investigates the foreshore sediment textural characteristics and grain size distribution following a renourishment cycle. Sediment samples n = 54 were collected in March (winter) and n = 57 in August (summer) 2024 along cross-shore profiles from the berm crest to the high tide line. The samples were sieved and analyzed for grain size distribution, sorting, skewness, and kurtosis using sieve analysis and GRADISTAT V8.0 software. Results indicate that Wildwood beaches in the winter (pre-nourishment) were very well-sorted fine sand, and in the summer (post-nourishment), well-sorted fine to medium sand. Cape May oceanside was predominantly well-sorted medium sand, symmetrical to coarse skewed in winter and fine skewed in summer. In contrast, Bayside consisted of more poorly sorted coarse sand, including gravel. Results indicate that Wildwood and Cape May Oceanside are depositional environments during both seasons, whereas Cape May Bayside in winter is an erosive setting with sporadic high-energy events and multiple sources of sediments. Ultimately, the long-term nourishment has caused an increase in overall average grain sizes of the beaches, where coastal structures alter the natural sediment transport and wave energy reaching the nearshore, impacting the distribution of sediments. Under modern conditions with decades of future anthropogenic influence, these beaches could demonstrate a greater resilience to erosion, while being more stable. These findings are applicable to future coastal management and habitat restoration projects.

Coastal lagoons are highly susceptible to the impacts of climate change. In lagoons of the Global South development challenges and growing coastal populations compound climate stressors to create complex inter-connected problems that cross social, economic and environmental boundaries. The successful governance of lagoons thus requires multidimensional approaches that combine disciplines and incorporate multiple knowledges. A stakeholder informed management framework was developed for West African lagoons using a transdisciplinary and participatory approach. A network of researchers from across the region, collectively known as the Resilient Lagoon Network, facilitated participatory platforms for stakeholders to share their experiences of the stressors facing lagoons and their management. Participants were from academia, government organisations, NGOs, traditional authorities and coastal lagoon communities. The information acquired enabled an understanding and relative importance of the challenges facing lagoons as well as what constituted good management practice and an appreciation for the breadth of lagoon stakeholders. From this information a framework was created comprising three strands that outlined the “what, how and who” of sustainable lagoon management. The “what” consists of a series of social, economic, environmental and governance indicators, linked to the sustainable development goals, that provide a checklist for lagoon sustainability. The “how” outlines tenets of good governance with an emphasis on equity, participation, cooperation and open communication. The “who” maps the range of possible lagoon stakeholders. The framework has been sense tested with lagoon practitioners and made available across the region. Although based on the experience of West African lagoon stakeholders, it could be used to inform the management of lagoons across the Global South.