Journal of Coastal Conservation最新文献

The encroachment of woody shrubs in grass-dominated coastal salt marsh ecosystems has potentially influenced soil physical and chemical processes at various scales. Understanding the effects of shrub encroachment on those ecosystems requires assessments of the spatial heterogeneity in soil variables across multiple scales. Combined with GIS spatial tools and sampling data, we evaluated the vertical (0–80 cm) and spatial characteristics of soil pH and soil salinity (or electrical conductivity, EC) in a coastal wetland that experienced 40 years of shrub (specifically, the Tamarix chinensis species) encroachment. In order to obtain the information of the spatial patterns and scale domains of soil pH and EC, we employed the lacunarity analysis method. Furthermore, we utilized both Mantel test and Pearson correlation to identify their relationship. The results revealed that shrub encroachment had notable impacts on the magnitude and spatial patterns of soil pH and EC. These effects were driven by specific encroaching processes. Specifically, large shrub patches (SP) resulted in a significant rise in soil pH and a noteworthy reduction in soil EC. In addition, small shrub clusters (SC) caused a notable reduction in soil EC, but did not have significant impacts on soil pH. The impacts of shrubs on soil pH were primarily observed in 0–20 cm, whereas their effects on soil EC extended to deeper soil layers (e.g., up to 60 cm). Shrub encroachment also increased the landscape heterogeneity of both soil pH and EC, with the effects being more pronounced on soil EC. The lacunarity analysis revealed that the spatial heterogeneity of soil EC differed significantly among four depths, 0–20, 20–30, 30–60, and 60–80 cm, while the heterogeneity of soil pH varied significantly between two depths of 0–60 and 60–80 cm. Furthermore, soil pH and soil EC showed a strong spatial association, with a negative relationship observed between the two variables within each soil layer. Our study at the landscape scale highlights the opposite responses of soil pH and EC in saline-alkali wetlands to shrub encroachment. By understanding the impacts of shrubs on soil properties, we can enhance our ability to effectively restore and manage these degraded ecosystems.

Beaches provide a buffer zone between the sea and the land, which mitigates the impact of natural hazards on waterfront residents. In this study, the beach at the Dakenggu community in Suao Township, Yilan, was used as a long-term monitoring site for ghost crabs. The survey was conducted by researchers in collaboration with local residents, which can be considered community-based citizen science. In collaboration, researchers and residents conducted monthly surveys. The findings showed that Ocypode sinensis was a dominant species on the Dakenggu beach. Juvenile O. sinensis were more abundant in the spring (April) and the summer (July–September). Except in September, no sex predominance was observed in other months, which may be related to the breeding period of the crabs. As far as other data are concerned, O. sinensis females were significantly larger than males, and O. sinensis occurrences exhibited a significant positive correlation with temperature and a significant negative correlation with relative humidity when weather data for the survey days were analyzed. Multiple studies have shown that the ghost crab population is highly affected by offroad vehicle use on the beach. As a result, local residents can use the findings of this study to develop corresponding conservation strategies, such as permitting off-road vehicle use only in the winter (November–February) and planting coastal plants as natural barriers to prevent vehicles from destroying ghost crab habitat. Long-term environmental monitoring through community-based citizen science can document changes in the local environment, and such information can be the basis for increased community resilience to face the challenges posed by environmental change.

Beach morphology assessment is very important for the sustainable development of beaches and the implementation of beach development activities through management plans. The present study focuses on assessing beach morphology and developing ecosystem-based conservative strategies to control beach erosion and improve beach safety along the two blue-flag certified beaches, Padubidri and Kasarkod, in Karnataka state. The bathymetry of the two beaches varies by gradient changes between the winter and monsoon seasons, and as a result, waves break at a distance of 15–25 m from the shore. The estimated seabed deposition between the winter and monsoon periods of 2020 is 10329 cu m and 59.36 cu m at the Padubidri and Kasarkod beaches, respectively. This study also provides the rate of shoreline change at two beaches along the coast for the period 2018–2022, as measured using geospatial technology and field investigation. The assessment revealed that the Kasarkod and Padubidri coasts experienced maximum erosion of 11.7% and 12.7%, respectively for five years. The projected shoreline changes under the climate change show erosion of 59.12 m on the northern side and accretion of about 16.13 m on the southern side of Kasarkod Beach, whereas on Padubidri Beach, erosion of 40 m on the central part of the beach between 2020 and 2030. The nearshore current magnitude is stronger at the coast of Padubidri than at Kasarkod during the study. The sediment movement from the Kamini River at the Hejamadi endpoint (southern part of Padubidri) shapes the Padubidri beach and causes accretion and erosion during winter and monsoon seasons respectively. However, these beaches are being protected by ecosystem-based conservative strategies such as beach vegetation and dune conservation through the Beach Environment and Aesthetics Management Services (BEAMS) program. Therefore, the assessment of beach morphology and conservation strategies provides a better beach management plan, to control beach erosion, and enhance beach stability.

Communication is a strategic management lever for promoting user knowledge, understanding, acceptance, support, and conservation-related pro-environmental behavior within Coastal and Marine Protected Areas (CMPAs). But while user segmentation is considered a traditional operational tool for targeting user audiences effectively within terrestrial protected areas, research also highlights a low level of concrete application to CMPAs. Based on Public Perceptions Research literature, this study explores a panel of eight theoretical variables that reflect the multidimensional character of recreationists’ perceptions of CMPAs and how the related results could inform appropriate CMPA communication strategies. Onsite face-to-face interviews with 1,000 users were conducted for seven recreational activities (hiking, surfing, scuba-diving, boating, sailing, kite-surfing, kayaking) across a total of ten local sites. Results revealed that despite sharing a common motivation for being in contact with nature, recreationists expressed diverse perceptions and attitudes toward CMPAs and management, which can be divided into five segments: “CMPA-Not-convinced” (31.3% of all recreationists), “CMPA-Local Conservator” (11.5%), “CMPA-Not-Responsible” (12.7%), “CMPA-Passers-by” (20.1%) and “CMPA-Convinced” (24.4%). Findings show the value of visitor segmentation as an operational tool to inform CMPA management and communication strategies in a context of low knowledge about visitor audiences.

The impact of waves, storm surge, and aeolian transport associated with Post-tropical Storm Fiona (offshore significant wave height ∽ 8 m, storm surge up to 2 m) on the sandy beaches and foredunes of the north shore of Prince Edward Island National Park (PEINP), Canada, are assessed. Management policies and practices, as they apply to sandy beach systems within PEINP, are reviewed in the context of the shoreline changes attributed to Fiona. The effectiveness of these policies and practices are evaluated to inform the potential performance of beach-foredune systems as natural protection measures that mitigate the impacts of large-magnitude storms and relative sea-level rise (RSLR) on shoreline change. The analyses utilise survey data, ground photography, and unoccupied aerial vehicle (UAV) imagery collected before (October 2021 to July 2022) and after (October 2022 and May 2023) Fiona. In general, the largest dunes were characterised by erosion of the stoss slope, with landward retreat of the dune toe by < 6 m and minimal impact on crest height and position. Small foredunes (< 5 m in height) generally showed significantly greater erosion in terms of dune profiles, with dune breaching occurring at some locations. Foredunes perched on bedrock and till, which were typically smallest in size, were subject to complete erosion, thereby exposing the hard underlying surface. Overall, the impact of Fiona on sandy beach systems in PEINP was relatively modest in many locations, reflecting the success of existing management policies and practices that protect and maintain the integrity of foredunes by minimizing human impacts and avoiding ‘coastal squeeze’.

Coastal cities in the Amazon lack basic infrastructure to treat and finally discharge urban domestic sewage. Implementing sub-river outfalls and waste-treatment pre-conditioning that significantly reduce pollution impact would be a sustainable alternative to cope with such an issue. The aim of the present research is to analyze the technical, economic and environmental feasibility of alternative projects applied to domestic waste’s proper destination in the coastal zone of Amapá State (ZCEA), Brazil. Infrastructure basic sizing and the current treatment provided to domestic waste discharged in Amazonas River, in natura, were taken into consideration for study conduction. Research methodology was applied as follows: (a) pre-sizing the main infrastructure elements of sub-river outfalls (EM); (b) assessing the reduction of impacts on quality of water in the metropolitan seashore of Macapá and Santana cities; (c) economic assessment based on the alternative implementation of underwater outfalls in Macapá’s Northern and Central zones, where one finds Amazonas River’s high self-depuration ability and regular bathymetry. Technical feasibility, mainly in Fazendinha and Santana cities, was not satisfactory due to topobathymetric unevenness and traffic jam in Santana Channel’s waterway. We have concluded that the self-depuration and sanitary features in Amazonas River’s assessed stretches are a sustainable, effective and competitive technology extremely favorable for the implementation of sub-river outfalls, given its simplicity and, most of all, adjustment to the regional socioeconomic reality.

In this piece of work, we provide comments on the paper: “Solar system planetary alignment triggers tides and earthquakes” by Awadh (2021). The paper claimed to undertake quantitative statistical analysis of earthquakes and planetary alignment across the world and, particularly, in the Zagros Region. As a result of his statistical analysis, he claimed that the alignment of the Earth with two planets in a straight line would generate earthquakes. However, after a careful review of the paper, we found that the analysis was qualitative in its major part. It is suffering from a lack of clarity for planetary alignment data and methods, in addition to a deficiency in earthquake data. We found that the major two tables (i.e., Tables 2 and 5) used by Awadh (2021) to demonstrate the relationship and the planetary alignment were not accurate. Our work demonstrates the problems of relying on inadequate and inappropriate datasets of Awadh’s (2021) paper.

The Sagar is the largest inhabited island in the Ganges delta in India. In the recent decades the island experiences severe stress and coastal instability due to multiple setbacks such as high erosion, degradation of coastal vegetation, frequent cyclones, dynamic changes in land features and rapid population growth. This study aims in assessing the spatial dynamics of the land features of the island during the past 45 years from 1972 to 2017 as two scenarios i) Short-term and ii) Long-term to evaluate the impacts on its coastline. The extended aim of the study was to predict the status of the land features in the island for the next two decades, ie 2027 and 2037 using CA–MARKOV model. The study indicated continuous loss of land to sea and depletion of coastal features such as mangroves, mudflats and sand dunes in both the scenarios. In view of the continuous erosion of the island’s coast, protective embankments have been constructed to protect life and property. The study indicated damage of embankments due to erosion over time. Analysis of recent changes indicated that strengthening the existing embankments together with restoration of natural systems such as mangroves would minimize erosion though it may not serve as an ultimate solution to combat erosion. Based on the population density living in close proximity to such eroding coasts along with its prevailing protection measures, the study classified such stretches as hotspots of category I, II and III.

Abstract

Globally, mangroves have been promoted to protect the coastal ecosystems and human settlements against weather vagaries including climate change impacts. However, climate change can also affect the mangrove ecosystems, affecting their ability to mitigate losses and damages caused by climate change. Recognizing the need to understand the impact of climate change on the ability of mangroves to mitigate loss and damage, this paper presents the impact of climate change on mangrove ecosystems in Dat Mui commune, Ngoc Hien district, Ca Mau province, Vietnam by using community-based methods. Results showed that the most noticeable impact of climate change is the loss in mangrove area, aquatic resources, and coastal erosion prevention. In addition, there is a decline in timber, firewood supply, and habitat of mangrove species. Despite adaptation actions taken by the local authorities and households, mangrove ecosystems are is still facing loss and damage. Solutions have been proposed to help the local and national authorities and communities to address losses and damages caused by the climate change.