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First detection of microplastics in reef-building corals from a Maldivian atoll
2022
Raguso, Clarissa | Saliu, Francesco | Lasagni, Marina | Galli, Paolo | Clemenza, Massimiliano | Montano, Simone
The presence of microplastics in the world's oceans and their effects on marine habitats are highly concerning. As suspension-feeders, corals are very exposed to microplastics, compromising the health of coral reef ecosystems. In this study we surveyed for the first time the presence of microplastics in Maldivian reef-building corals. Aiming to determine the influence of exposure and depth on microplastic distribution, analyses were carried out on 38 individuals belonging to three different species. 58% of the investigated colonies resulted contaminated with particles within the 25–150 μm size range. The maximum concentration was encountered in a Pocillopora verrucosa colony sampled from a shallow inner reef (8.9 particles/g of coral). No significant differences in microplastic concentration were observed between different depths, exposures, sites and species. Overall, this study confirmed microplastic presence in coral reefs of the Maldivian archipelago including foundation species.
Показать больше [+] Меньше [-]Synergic effect of global thermal anomalies and local dredging activities on coral reefs of the Maldives
2020
Pancrazi, Irene | Ahmed, Hassan | Cerrano, Carlo | Montefalcone, Monica
We investigated possible synergic effects on coral reefs of the local land reclamation activities in the Himmafushi Island (North Malè atoll, Maldives) and the global bleaching event that affected the Maldives in 2016. A BACI (Before-After Control-Impact) sampling design was adopted to contrast effects of dredging activities before and after the occurrence of both dredging and bleaching. The Reef Check protocol, a standardised and worldwide survey method, was applied to collect data through underwater visual surveys on corals, macro-zoobenthos, and fish communities. The bleaching in 2016 hit all the reefs investigated, but only in the reefs around Himmafushi (i.e., the impact sites) the live hard coral reduced significantly its cover and the sand deposited on reefs showed a fourfold increase. Substrate indicators (i.e., coral community and abiotic components) turned out to be more effective than macro-zoobenthos and fish in this short-term environmental impact study.
Показать больше [+] Меньше [-]Microplastic and charred microplastic in the Faafu Atoll, Maldives
2018
Saliu, Francesco | Montano, Simone | Garavaglia, Maria Grazia | Lasagni, Marina | Seveso, Davide | Galli, Paolo
Microplastics are recognized as a growing threat for the marine environment that may even affect areas generally considered pristine. In this work we surveyed the microplastic contamination in the Faafu Atoll (Maldives, Indian Ocean) across twelve sampling station, located either inside or outside the reef rim. Sediments and seawater samples were collected. Despite the remoteness of the atoll, the scarce local population and low touristic annual afflux, the detected average abundance were 0.32 ± 0.15 particles/m3 in the surface water and 22.8 ± 10.5 particles/m2 in the beach sediments. Polymers identified through Fourier-Transform Infrared spectroscopy were mostly polyethylene, polypropylene, polystyrene, polyvinylchloride, polyethyleneterephtalate, and polyamide. Elastomeric residues and charred microparticles were also found. In particular, the charred microparticles were prevalently located nearby the inhabited island and they might be considered a peculiarity of the area, related to local practice of burning plastic waste at the shoreline.
Показать больше [+] Меньше [-]Spatial and temporal variation of macro-, meso- and microplastic abundance on a remote coral island of the Maldives, Indian Ocean
2017
Imhof, Hannes K. | Sigl, Robert | Brauer, Emilia | Feyl, Sabine | Giesemann, Philipp | Klink, Saskia | Leupolz, Kathrin | Löder, Martin G.J. | Löschel, Lena A. | Missun, Jan | Muszynski, Sarah | Ramsperger, Anja F.R.M. | Schrank, Isabella | Speck, Susan | Steibl, Sebastian | Trotter, Benjamin | Winter, Isabel | Laforsch, Christian
Plastic debris is ubiquitous in the marine environment and the world's shores represent a major sink. However, knowledge about plastic abundance in remote areas is scarce. Therefore, plastic abundance was investigated on a small island of the Maldives. Plastic debris (>1mm) was sampled once in natural long-term accumulation zones at the north shore and at the high tide drift line of the south shore on seven consecutive days to quantify daily plastic accumulation. Reliable identification of plastic debris was ensured by FTIR spectroscopy. Despite the remoteness of the island a considerable amount of plastic debris was present. At both sites a high variability in plastic abundance on a spatial and temporal scale was observed, which may be best explained by environmental factors. In addition, our results show that snapshot sampling may deliver biased results and indicate that future monitoring programs should consider spatial and temporal variation of plastic deposition.
Показать больше [+] Меньше [-]Through bleaching and tsunami: Coral reef recovery in the Maldives
2015
Morri, Carla | Montefalcone, Monica | Lasagna, Roberta | Gatti, Giulia | Rovere, Alessio | Parravicini, Valeriano | Baldelli, Giuseppe | Colantoni, Paolo | Bianchi, Carlo Nike
Coral reefs are degrading worldwide, but little information exists on their previous conditions for most regions of the world. Since 1989, we have been studying the Maldives, collecting data before, during and after the bleaching and mass mortality event of 1998. As early as 1999, many newly settled colonies were recorded. Recruits shifted from a dominance of massive and encrusting corals in the early stages of recolonisation towards a dominance of Acropora and Pocillopora by 2009. Coral cover, which dropped to less than 10% after the bleaching, returned to pre-bleaching values of around 50% by 2013. The 2004 tsunami had comparatively little effect. In 2014, the coral community was similar to that existing before the bleaching. According to descriptors and metrics adopted, recovery of Maldivian coral reefs took between 6 and 15years, or may even be considered unachieved, as there are species that had not come back yet.
Показать больше [+] Меньше [-]Community change and evidence for variable warm-water temperature adaptation of corals in Northern Male Atoll, Maldives
2014
McClanahan, T.R. | Muthiga, N.A.
This study provides a descriptive analysis of the North Male, Maldives seven years after the 1998 bleaching disturbance to determine the state of the coral community composition, the recruitment community, evidence for recovery, and adaptation to thermal stress. Overall, hard coral cover recovered at a rate commonly reported in the literature but with high spatial variability and shifts in taxonomic composition. Massive Porites, Pavona, Synarea, and Goniopora were unusually common in both the recruit and adult communities. Coral recruitment was low and some coral taxa, namely Tubipora, Seriatopora, and Stylophora, were rarer than expected. A study of the bleaching response to a thermal anomaly in 2005 indicated that some taxa, including Leptoria, Platygyra, Favites, Fungia, Hydnophora, and Galaxea astreata, bleached as predicted while others, including Acropora, Pocillopora, branching Porites, Montipora, Stylophora, and Alveopora, bleached less than predicted. This indicates variable-adaptation potentials among the taxa and considerable potential for ecological reorganization of the coral community.
Показать больше [+] Меньше [-]Minimum drift times infer trajectories of ghost nets found in the Maldives
2020
Stelfox, Martin | Lett, Christophe | Reid, Geraldine | Souch, Graham | Sweet, Michael
This study explores methods to estimate minimum drift times of ghost nets found in the Maldives with the aim of identifying a putative origin. We highlight that percentage cover of biofouling organisms and capitulum length of Lepas anatifera are two methods that provide these estimates. Eight ghost nets were collected in the Maldives and estimated drift times ranged between 7.5 and 101 days. Additionally, Lagrangian simulations identified drift trajectories of 326 historical ghost nets records. Purse seine fisheries (associated with Korea, Mauritius, the Philippines, Spain, France and Seychelles) and gill nets from Sri Lanka were identified as 'high risk' fisheries with regard to likley origins of ghost nets drifting into the Maldives. These fisheries are active in areas where dense particle clusters occured (drift trajectories between 30 and 120 days). Interestingly, ghost nets drifting less than 30 days however, remained inside the exclusive economic zone of the Maldivian archipelago highlighting potential illegal, unreported and unregulated fishing activity is occuring in this area. This study therefore points to the urgent need for gear loss reporting to be undertaken, especially by purse seine and gill net fisheries in order to ascertain the source of this major threat to marine life. This should also be coupled with an improvment in the data focused on spatial distribution of the abandoned, lost or discarded fishing gear originating from both large- and small-scale fisheries.
Показать больше [+] Меньше [-]First record of emerging contaminants in sponges of an inhabited island in the Maldives
2020
Rizzi, Cristiana | Seveso, Davide | Galli, Paolo | Villa, Sara
In the Maldivian islands, the lack of sewage wastewater treatment and an improper landfill enhance the potential hazard of emerging contaminants, including pharmaceuticals and personal care products. In order to analyze the occurrence of emerging contaminants in the marine biota, sponges were collected in two coral reef areas of Magoodhoo island (Faafu), one near the landfill and the other furthest from the island. Caffeine, fluoxetine and norfluoxetine were detected only in the proximity of the landfill, with caffeine showing the highest concentration (28.4 ng/g d.w.), followed by fluoxetine (6.00 ng/g d.w.). Norfluoxetine was below the limit of quantification of 10 ng/g d.w. Nitro xylene, N,N-Diethyl-meta-toluamide and galaxolide were found in both areas, with concentrations of 3.51/6.11/8.54 and <LOQ/1.14/0.62 ng/g d.w., respectively. Due to the vital role of the coral reef for the livelihood and economy of the Maldivian people, attention should be paid to this class of contaminant.
Показать больше [+] Меньше [-]Spatial variability of phthalates contamination in the reef-building corals Porites lutea, Pocillopora verrucosa and Pavona varians
2020
Montano, Simone | Seveso, Davide | Maggioni, Davide | Galli, Paolo | Corsarini, Stefano | Saliu, Francesco
Microplastic pollution represents a serious hazard for the marine environment, including coral reefs. Scleractinian corals can easily mistake microplastics with their natural preys, and ingest them and all the annexed plasticizer additives. Here we selectively searched on field for five phthalates esters (PAEs) namely dibutyl-phthalate (DBP), benzylbutyl-phthalate (BBzP), diethyl-phthalate (DEP), Bis(2-ethylhexyl)-phthalate (DEHP), and dimethyl-phthalate (DMP) in the coral species Pocillopora verrucosa, Porites lutea and Pavona varians. Our data reveal that >95% of corals sampled were contaminated, with a maximum of 172.4 ng/g, a value 7 time-fold higher than those found in a previous study. The Σ₅ PAEs showed an average of about 30 ng/g per coral, but no differences in PAEs contamination was detected between species, depth or reef exposure. Despite their effects on coral physiology are not yet known, PAEs should be now considered as a novel, and ubiquitous, form of contamination in corals.
Показать больше [+] Меньше [-]Unlocking the role of energy poverty and its impacts on financial growth of household: is there any economic concern
2022
Chien, Fengsheng | Hsu, Ching-Chi | Zhang, YunQian | Vu, Hieu Minh | Nawaz, Muhammad Atif
The major purpose of this study is to assess racial disparity and energy poverty index by measuring energy poverty index by using data envelopment analysis and regression equation from South Asia (2001–2018). An energy poverty index is quantifying the size and scope of energy poverty, and DEA is used to investigate the relevance of socioeconomic position to multidimensional energy poverty. In multidimensional energy poverty, location, house ownership position, number of dependents, and the age of the main caregiver have an important positive impact. Our research has shown that Bhutan is the most susceptible nation with an energy poverty index of (0.02), Maldives (0.03), and Bangladesh (0.11), while India (0.86) and Pakistan (0.49) are the least likely to be energy poor as regards energy poverty. Of the total energy production, 78% is based on traditional fuels, followed by 12% based on petroleum products. The Gini index indicates a positive association with the energy poverty index at a 5% significance level. This signifies that these socioeconomic indicators positively contribute to the energy poverty index level. This study developed more synchronized policies to eradicate energy poverty and can provide a way forward for policymakers to develop strategies to implement them suitably in the regional power sector.
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