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Ecosystem services, encompassing the direct and indirect benefits of natural systems, are extensively studied in the context of mangroves. These carbon-rich ecosystems support coastal fisheries, shorelines, and harvestable resources to local communities. However, research on mangrove ecosystem services primarily are at a local scale, with limited exploration of global variations in resource utilization. This paper aims to bridge this knowledge gap through a systematic review of the existing literature conducted in Web of Science to assess the geographical variations in the coverage of mangrove use and ecosystem services. Out of 310 papers analyzed, Asia had the highest coverage (43%) with support to fisheries (39%) being the most researched ecosystem service worldwide. Direct use of mangrove resources exhibited regional variations, particularly in Asia, Africa, and North America. Mangrove wood, primarily used for fuel (16%) and construction (15%), was the most documented resource, with its usage persisting in low-income countries. Notably, a shift from being a primary income source to subsistence use was observed in Asia, Africa, and South America. Intrinsic and cultural services were less mentioned in the literature, emphasizing the need for future studies to focus on these areas to ensure culturally sensitive conservation efforts. [ABSTRACT FROM AUTHOR]

Deforestation and overexploitation of mangrove forests are affecting the livelihoods of millions of families that rely on their ecosystem services. Understanding local perceptions about the status and threats to mangroves is therefore crucial in addressing this issue. This research aims to enhance understanding of how sociodemographic factors influence resource use and perceptions of environmental changes through a questionnaire survey (n = 592 households) in five locations in Lamu County, home to 62% of Kenya's mangroves. The results highlight the variability of mangrove use, ecosystem service recognition, and perceptions and drivers of change across locations, which are influenced by sociodemographic factors such as gender, education, and occupation. Although 89% of respondents reported using mangrove products, only 56% were able to identify mangrove ecosystem services, with those without formal education being less likely to recognize them. Interestingly, 50% of respondents perceived an increase in mangrove cover, contrary to research showing mangrove loss in the area over the last decade. Results show that communities are diverse and perceptions vary between groups, suggesting that implementing uniform management measures may be incomplete or ineffective. Awareness campaigns and capacity-building efforts must be tailored to reduce misperceptions about the state of local resources and to address the specific needs and challenges faced by different groups. Recommendations made here are widely applicable to promote more inclusive and sustainable community engagement in the management of natural resources in developing countries worldwide. [ABSTRACT FROM AUTHOR]

The Manila clam Ruditapes philippinarum is one of the most commercially valuable bivalve species worldwide and its range is expanding, facilitated by aquaculture and fishing activities. In existing and new systems, the species may become commercially and ecologically important, supporting both local fishing activities and populations of shorebird predators of conservation importance. This study assessed potential fishing effects and population dynamics of R. philippinarum in Poole Harbour, a marine protected area on the south coast of the UK, where the species is important for oystercatcher Haematopus ostralegus as well as local fishers. Sampling was undertaken across three sites of different fishing intensities before and after the 2015 fishing season, which extends into the key overwintering period for shorebird populations. Significant differences in density, size and condition index are evident between sites, with the heavily dredged site supporting clams of poorer condition. Across the dredge season, clam densities in the heavily fished area were significantly reduced, with a harvesting efficiency of legally harvestable clams of up to 95% in this area. Despite occurring at significantly higher densities and growing faster under heavy fishing pressure, lower biomass and condition index of R. philippinarum in this area, coupled with the dramatic reduction in densities across the fishing season, may be of concern to managers who must consider the wider ecological interactions of harvesting with the interest of nature conservation and site integrity.

Understanding the impact of bottom-fishing gears at various scales and intensities on habitats and species is necessary to inform management. In Poole Harbour, UK, a multiple use marine protected area, fishermen utilise a unique ̋“pump-scoop” dredge to harvest the introduced Manila clam Ruditapes philippinarum. Managers need to balance the socio-economic benefits of the fishery with ecological concerns across the region, which has required a revision of by-laws that include both spatial and temporal measures. Within an operational fishery, we used a Before-After-Control-Impact sampling design to assess the impacts of pump-scoop dredging on benthic physical characteristics and community structure in an area where there was no dredging, an area newly opened to dredging and an area subject to high levels of historic dredging. A sampling grid was used in each area to best capture any fishing effort in the newly opened area. Core samples were taken to a depth of 30 cm within intertidal mudflats. A significant loss of fine sediments was observed in the site subject to high intensity dredging and a significant change in community structure also occurred in both dredged sites throughout the study period. In the newly opened site this was characterised by a relative increase in species richness, including increased abundance of annelid worms, notably Hediste diversicolor and Aphelochaeta marioni and a decline in the abundance of the bivalve mollusc Abra tenuis. These changes, albeit relatively small, are attributed to physical disturbance as a direct result of pump-scoop dredging, although no difference in the classification of the biotope of the site was observed. This is of particular interest to managers monitoring site condition within areas under the new by-laws as the Manila clam is spreading to other protected estuaries in the region.

Evidences of coastal erosion in Rio Grande do Sul have been obtained by three methods: (a) analysis of the long-term morphodynamics and stratigraphy of coastal barriers, (b) annual shoreline mapping using the Differential Global Positioning System (DGPS), and (c) local beach profile measurements. The first method reflects coastal erosion as continuity of the geological evolution in the last 5 ka, taking place mainly along the southern half of gentle coastal projections. The second method represents a shorter temporal scale and indicates that approximately 80% of the coast is eroding. Beach profiling has been measured in very few places that are distant from each other since the early 1990s; consequently, their results reflect local and very short time shoreline behavior. A critical evaluation of published data addressing coastal erosion in Rio Grande do Sul strongly suggests that short and long term negative balance on the sediment budget is the main cause of erosion along this coastline.