Affiner votre recherche
Résultats 1-10 de 31
Qualitative Analysis of Plastic Debris on Beaches of Brunei Darussalam
2020
Qaisrani, Z. | Shams, S. | Guo, Z. R. | Mamun, A. A.
Plastic debris is one of the major environmental concerns for the coastal area of Brunei Darussalam. It reduces the aesthetic appeals of the beaches in the country. The current study investigates marine debris on six different beaches of Brunei Darussalam along the South China Sea. Plastic was found the most abundant among whole debris by number (90.02%) and by weight (39.12%). It was classified by size (micro (<5 mm), meso (5-20 mm), macro (21-100), and mega (>100 mm)), colour (transparent, coloured, white and black). Fourier Transform Infrared Spectroscopy (FT-IR) was used to investigate the types of plastics and additives present in it. Statistical analysis using Minitab 17 and Kruskal-Wallis test was performed for comparison of data at different study sites. All major types of plastics were found in different forms with varying quantities from which toxic chemicals may leach out during degradation. The highest abundance by the number of plastic debris was found on Muara beach with a mean value 74.428 n/m2 ± 34.33 n/m2, while the lowest abundance was found on Lumut beach 53 n/m2 ± 20.9 n/m2. The study shows beaches used for recreational facilities are likely to have more debris as compared to other beaches.
Afficher plus [+] Moins [-]Check List of Species Richness and Abundance of Orthoptera Fauna in Bharathi Park, Coimbatore, Tamil Nadu, India
2022
M. Suganya | K. Manimegalai
Order Orthoptera is one of the largest and most important invertebrate groups for environmental monitoring and assessment. Orthoptera faunal composition was carried out at Bharathi Park, Coimbatore, Tamil Nadu, India to evaluate the present status of various species. PAST software was used to perform various statistical analyses to estimate the Orthoptera composition. Overall, 334 individuals belonging to 22 species, 19 genera, 17 tribes under 10 subfamilies, and four families of Orthoptera were recorded. Species richness (59.09%) and species abundance (70.06%) were recorded highest in the Acrididae family followed by Pyrgomorphidae, Tettigoniidae, and Gryllidae. Oedipodinae was the most species-rich (27.27%) and the most abundant subfamily, accounting for 30.24% of the total collected individuals. During the study period, 10 dominant, five intermediate dominance, four incidental, and three rare species were observed. Among these, Spathosternum prasiniferum was found to be the most dominant species (D=18.26) and the least dominant (D = 0.6) species was Euconocephalus pallidus. Based on the principal component analysis, the distribution of species along with the first two PCs (PC1= 33.87% and PC2=28.68%) accounted for the highest variance of the total variances. Cluster analysis showed that Acrotylus humbertianus and Teleogryllus mitratus, Conocephalus maculates and Gryllus bimaculatus Orthopterans were similar to each other. The value of the Shannon diversity index (2.27), Simpson index (0.87), Margalef index (2.2), and α-diversity (5.75) were higher in Acrididae when compared with other families. Value of Evenness (0.93) was highest in Gryllidae. Statistical analysis infers that the richness and abundance percentage of Orthopterans significantly varied between species to species and family to family.
Afficher plus [+] Moins [-]Features of the accumulation of macroplastic on the river bottom in the Mekong delta and the impact on fish and decapods
2022
Karpova, Evgeniia | Abliazov, Ernes | Statkevich, Svetlana | Dinh, Cu Nguyen
For the first time, a quantitative assessment of this pollutant was made at the bottom of the rivers of the Mekong basin, and the features of its accumulation and dynamics in bottom sediments and relationship with abundance of fish and decapods were investigated. Sampling of materials for the research was carried out by bottom trawls in the Mekong delta in Vietnam. The amount of macroplastic caught by the trawl from the bottom averaged 33.4 g/100 m². The maximum values of the waste content (up to 923.2 g/100 m²) were confined to the districts of large cities. The distribution of macroplastic was characterized by high spatio-temporal variability. Its amount was significantly (p < 0.05) higher in branches with low monthly flow, in shallow-water areas, as well as in the low-water period. During the flood period, which usually lasts from July to November, the amount of macroplastic at the bottom decreased by an average of 2.5 times. In this study a significant relationship between the number of animals and the mass of macroplastics was statistically proven for most species of fish and decapods. The substrate, containing a significant amount of plastic fragments, attracted aquatic organisms. All in all, we present results for poorly understood processes of transport, deposition and influence of plastic debris in large rivers in regions of monsoon subequatorial climate and show that more efforts should be dedicated to further unravel potentially complex pathways of the plastic exposure to water ecosystems.
Afficher plus [+] Moins [-]Abundance, composition, and distribution of microplastics larger than 20 μm in sand beaches of South Korea
2018
Eo, Soeun | Hong, Sang Hee | Song, Young Kyoung | Lee, Jongsu | Lee, Jongmyoung | Shim, Won Joon
To support microplastic management, the abundance, composition, and spatial distribution of microplastics on a national scale must be known. Hence, we studied the baseline level of microplastic pollution at 20 sandy beaches along the South Korean coast. All microplastic particles extracted from the sand samples were identified down to 20 μm in size using Fourier transform infrared spectroscopy. The abundances of large microplastics (L-MPs; 1–5 mm) and small microplastics (S-MPs; 0.02–1 mm) were in the range of 0–2088 n/m2 and 1400–62800 n/m2, respectively. Maximum microplastic abundance was in the size range of 100–150 μm, and particles smaller than 300 μm accounted for 81% of the total abundance. Expanded polystyrene (EPS) accounted for 95% of L-MPs, whereas S-MPs were predominantly composed of polyethylene (49%) and polypropylene (38%). The spatial distribution of L-MPs, excluding EPS, was significantly related to population, precipitation, proximity to a river mouth and abundance of macroplastic debris on beach. However, there were no relationships between S-MPs and other environmental and source-related factors, except for macroplastic debris and L-MPs excluding EPS. These results imply that S-MPs are mainly produced on beaches by weathering, whereas L-MPs other than EPS are mainly introduced from land-based sources and are also partly produced on beaches.
Afficher plus [+] Moins [-]Abundance and characteristics of microplastics in an urban wastewater treatment plant in Turkey
2022
Üstün, Gökhan Ekrem | Bozdaş, Kübra | Can, Tuğba
Wastewater treatment plants (WWTPs) are considered one of the important sources of aquatic/terrestrial microplastic (MP) pollution. Therefore, the abundance and properties of MPs in the wastewater and sludge of an urban WWTP in Bursa Turkey were investigated. The amount, properties, and removal of MPs were evaluated. The results showed that the average abundance of MPs was 135.3 ± 28.0 n/L in the influent and 8.5 ± 4.7 n/L in the effluent, with a 93.7% removal rate, MP was removed and transferred to the sludge. The daily MP amount released in the aquatic environment is calculated as 525 million MPs, and the annual amount is 1.9 × 10¹¹ MPs. The abundance of MPs in the sludge thickening and sludge filter cake is 17.9 ± 2.3 and 9.5 ± 2.3 n/g dry weight (dw), respectively. The sludge disposal amount of WWTP is 81.5 tons/day and the approximate amount of MP accumulated in the sludge per year is calculated as 2.8 × 10¹¹ MPs. In wastewater and sludge samples, fragment dominant shape, black main colour, and 500–1000 μm sizes are the most common size. The main MP types in wastewater samples at the influent are polypropylene (PP, 36.8%), polyethylene (PE, 31.0%), polystyrene (PS, 11.8%), polyethylene terephthalate (PET, 8.0%), and polyamide (PA, 7.1%), at the effluent (PE, 33.0%), (PP, 52.5%), and (PS, 8.2%). In the sludge cake, the distribution is (PE, 40.8%), (PP, 27.6%), (PS, 18.7%) and (PET, 8.0%). The results of this study show that MPs are removed from wastewater with high efficiency by treatment processes and a significant amount accumulates in the sludge. Therefore, it is suggested that to integrate advanced treatment processes into urban WWTPs and use effective sludge disposal management practices to reduce the amount of MP released into the environment with effluent and sludge.
Afficher plus [+] Moins [-]Microplastic abundance, distribution and composition in the mid-west Pacific Ocean
2020
Wang, Sumin | Chen, Hongzhe | Zhou, Xiwu | Tian, Yongqing | Lin, Cai | Wang, Weili | Zhou, Kaiwen | Zhang, Yuanbiao | Lin, Hui
Microplastic pollution is widespread across most ocean basins around the world. Microplastics (MPs) are small plastic particles that have a significant impact on the marine environment. Various research on plastic pollution have been conducted in several regions. However, currently, there is limited data on the distribution and concentration of MPs in the mid-west Pacific Ocean. Therefore, this study we investigated the abundance, distribution, characteristics, and compositions of MPs in this region. Sea surface water samples collected from 18 stations showed a microplastic concentration range of 6028–95,335 pieces/km² and a mean concentration of 34,039 ± 25,101 pieces/km². Highest microplastic concentrations were observed in the seamount region of western Pacific. We observed a significant positive correlation between microplastic abundance and latitude across the study region. It was observed that microplastic concentrations decreased with increasing offshore distance at sites located on a 154° W transect. Fibres/filaments were the dominant microparticles observed in this study (57.4%), followed by fragments (18.3%). The dominant particle size range was 1–2.5 mm (35.1%), followed by 0.5–1 mm (28.5%), and the dominant particle colour was white (33.8%), followed by transparent (31.0%) and green (24.6%). The most common polymer identified by μ-Raman was polypropylene (39.1%), followed by polymethyl methacrylate (16.2%), polyethylene (14.1%) and polyethylene terephthalate (14.2%). The possible sources and pathways of microplastics in the study area were proposed based on the morphological and compositional characteristics of particles, their spatial distribution patterns, and shipboard current profiling (ADCP). Our study contributes to the further understanding of MPs in remote ocean areas.
Afficher plus [+] Moins [-]Research and management of plastic pollution in coastal environments of China
2019
Wang, Mary H. | He, Yaodong | Sen, Biswarup
Marine plastic waste has become an ever-increasing environmental threat in the world’s ocean largely due to their unique properties and ubiquitous occurrence. They include diverse forms of land- and ocean-based sources of plastics and are estimated to account for up to 85% of marine debris worldwide. As secondary pollutants, marine microplastic particles (<5 mm) are derived from pellet loss and degradation of macroplastics. Up to now, several reports have proposed negative impacts of both macro-sized and micro-sized plastics on marine biota. As one of the rapidly growing economies, China is the topmost contributor of plastic waste in the world. China’s massive impact on the plastic levels of the ocean are a definite cause of concern and is developing multiple economic, environmental and biological complications. The research of plastics impact on coastal environments in China is only incipient. Here we review the available information on plastic waste, their impacts on marine biota and human health, and Chinese government policies and management initiatives. Although Chinese coastal environments (surface water, coastal sediments, water column) are affected by microplastics pollution, both from land-based and sea-based activities, their impacts on marine biota remain to be elucidated. Though national-level policies are modern and well suited for minimizing the impacts of plastic pollution, there is hardly any legislation for containment of microplastic pollution. Our objective is to review and summarize the information about the occurrence, impacts, and management of plastic pollution in the Chinese coastal environments in order to comprehend their widespread repercussions.Microplastics are increasingly being detected and quantified in Chinese coastal environments and legislation for containment of such pollution is highly recommended.
Afficher plus [+] Moins [-]First record of microplastic occurence at the commercial fish from Orontes River
2022
Kiliç, Ece | Yücel, Nebil | Mübarek Şahutoğlu, Seycan
Freshwater environments are more sensitive to anthropogenic influences and usually contain higher concentrations of pollutants than marine environments. Microplastic pollution causes additional stress on freshwater animals; yet, studies evaluating the microplastic occurrence in freshwater biota are still limited. In this study, microplastic occurrence in the gastrointestinal tracts (GIT) and gill of commercial fish species (Prussian carp Carassius gibelio (Bloch, 1782); Abu mullet Planiliza abu (Heckel, 1843); Common carp Cyprinus carpio Linnaeus, 1758; European ell Anguilla Anguilla (Linnaeus, 1758); North African catfish Clarias gariepinus (Burchell, 1822); Goldfish Carassius auratus (Linnaeus, 1758) were reported from Orontes River. MPs abundance in the GIT and gill of six species were found as 5.1 ± 2 MPs fish⁻¹ and 4.4 ± 2 MPs fish⁻¹ with an occurrence of 95% and 74%, respectively. The majority of extracted microplastics were fiber, black and less than 1000 μm in size. FTIR analysis determined the main polymer types as polyester (50%), high-density polyethylene (HDPE) (10%), polypropylene (PP) (8%) and polyethylene terephthalate (PET) (5%). High MPs abundance and frequency of occurence indicate the exposure of microplastic pollution in freshwater biota which could threat the health of both individuals and consumers. Results obtained in this study will increase the acknowledgement of MPs pollution in the Orontes River. Also, this study will provide data to the administrators to set up necessary legislations in freshwater ecosystems.
Afficher plus [+] Moins [-]Occurrence of microplastics in gastrointestinal tracts and gills of fish from Beibu Gulf, South China Sea
2020
Koongolla, J Bimali | Lin, Lang | Pan, Yun-Feng | Yang, Chang-Ping | Sun, Dian-Rong | Liu, Shan | Xu, Xiang-Rong | Maharana, Dusmant | Huang, Jian-Sheng | Li, Heng-Xiang
Microplastics are widespread across the global oceans, yet the potential risks of the ubiquitous environmental contaminant to marine organisms has been less known. Accumulation of microplastics and associated contaminants in marine fish, may pose adverse impacts to human health via seafood consumption. This study evaluated microplastic contamination in 24 fish species collected from Beibu Gulf, one of the world’s largest fishing grounds in South China Sea. Microplastics were detected in 12 fish species at an abundance of 0.027–1.000 items individual⁻¹ and found in fish stomach, intestines and gills with the count percentage of 57.7%, 34.6% and 7.7%, respectively. Transparent fibers were observed as the predominant microplastics, which might be ingested accidently by fish or transferred through other animals at lower trophic levels. Majority of microplastics were identified as polyester (44%) and nylon (38%), whereas polypropylene (6%), polyethylene (6%), and acrylics (6%) were also found. Relatively, higher microplastic abundances were found in demersal fish compared to the pelagic species. Overall, the abundance of microplastics was documented as relatively low in the commercial fish collected from the open water of Beibu Gulf, South China Sea.
Afficher plus [+] Moins [-]Distribution characteristics of microplastics in Zhubi Reef from South China Sea
2019
Wong, David Yau-kar | Yan, Muting | Xu, Kaihang | Nie, Huayue | Gong, Han | Wang, Jun
As a new type of emerging pollutant in the ocean, microplastics have received global attention in recent years. Considering the increasing amount of human activities around the South China Sea, it is important to determine the current status of microplastic pollution in this region. In this study, we analyzed the abundance and distribution of microplastics at Zhubi Reef in the South China Sea. Microplastic abundance ranged from 1,400 to 8,100 items/m3 of surface water, which was much higher than the values reported from other ocean areas. About 80% of the microplastics were smaller than 0.5 mm in size. Fibers and pellets comprised the most common microplastic types. The dominant microplastics were transparent or blue in color. The main polymer types were polypropylene (25%) and polyamide (18%). In general, our results revealed Zhubi Reef was contaminated with microplastics, which were likely derived from the intensive fisheries in the area and emissions from coastal cities. This study also provides baseline data that are useful for additional studies of microplastics in the South China Sea.
Afficher plus [+] Moins [-]