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Using photographs to record plastic in seabird nests Полный текст
2020
Ryan, Peter G.
The incidence of plastic in seabird nests can be used to track changes in the amounts of marine debris, but large sample sizes are needed for accurate estimates. Surveys of active nests cause disturbance to breeding birds, so we need an efficient way to sample nest plastics. Photographs of brown noddy Anous stolidus nests at Ducie Atoll, southeast Pacific Ocean, allowed rapid characterisation of plastic use with limited disturbance, and showed selection for blue-green items. Plastic was more prevalent in noddy nests at Ducie Atoll (97%) than at Inaccessible Island, South Atlantic Ocean (41%), despite lower debris densities at Ducie. Differences in nesting habitat and the resultant availability of natural nesting material drive this difference in plastic loads. Using photographs to record plastic in seabird nests reduces disturbance to breeding birds and might decrease the risk of missing cryptic debris items. Photographs also provide a permanent record of pollution levels.
Показать больше [+] Меньше [-]Impact of Diuron contamination on blood cockles (Tegillarca granosa Linnaeus, 1758) Полный текст
2020
Mohamat-Yusuff, Ferdaus | Zulkarnain, Zurfatiha | Anuar, Nurul Zatul Amira | Joni, Amirul Azuan Md | Kusin, Faradiella Mohd | Mohamed, Khairul Nizam | Zulkeflee, Zufarzaana | Asha'ari, Zulfa Hanan | Zulkifli, Syaizwan Zahmir | Arshad, Aziz | Ismail, Ahmad
Examination of the impact of Diuron contamination on blood cockles (Tegillarca granosa) was conducted by combining field screening at three sampling events and a toxicity test. Diuron was extracted using the liquid–liquid extraction (LLE) technique and analyzed using HPLC-UV. The median lethal concentration (LC₅₀) of Diuron on T. granosa was tested under a 72-h exposure. Diuron in water samples ranged from not detected (ND) to 3910 ppb, which was the highest concentration detected in samples after the irrigation water was discharged from the paddy plantation. Diuron was not detected in sediment samples. Mortality of T. granosa ranged from 4.74 to 38.33% with the highest percentages recorded after the release of the irrigation water. The LC₅₀ value of Diuron was 1.84 ppm. This study suggests that irrigation water from paddy plantation that drifts to coastal areas containing Diuron harms T. granosa at the study area.
Показать больше [+] Меньше [-]A persistent increase in primary productivity east off Hainan Island (northwestern South China Sea) over the last decades as inferred from sediment records Полный текст
2020
Liu, Mingyang | Li, Chao | Zhang, Fang | Zhang, Run | Yang, Weifeng | Chen, Min | Zheng, Minfang | Qiu, Yusheng
Sediment cores were analyzed from the continental shelf of the northwestern South China Sea aiming to understand the change history of primary productivity and provide insights into key changes of environmental conditions in this region over the past ~100 years. Multiple proxies including stable carbon isotopic composition (δ¹³C) of sedimentary organic matter, diatom abundance and biogenic silica burial flux were applied along with ²¹⁰Pb chronology. Notably, these independent evidences consistently point to a steady increase of primary production in this region only after ~1960s. We propose that increasing atmospheric deposition due to dramatically enhanced human activities especially from China supplies essential nitrogen nutrients to the N-poor region and probably acts a major reason for the observed enhancement of marine primary production. Our study provides insights into better understanding how human perturbation may have profoundly impacted biogeochemical cycling in marginal seas in the last decades.
Показать больше [+] Меньше [-]Accumulation and effects of microplastic fibers in American lobster larvae (Homarus americanus) Полный текст
2020
Woods, Madelyn N. | Hong, Theresa J. | Baughman, Donaven | Andrews, Grace | Fields, David M. | Matrai, Patricia A.
The effects of microplastic fibers (MPF) on the survival, molting and oxygen consumption rates of larval (I-III) and post-larval (IV) stages of the American lobster, Homarus americanus, were quantified as a function of MPF concentration and food availability. Only the highest MPF concentration decreased early larval survival. MPF did not affect the timing or rate of molting across MPF treatments. While all larval and post-larval stages accumulated MPF under the cephalothorax carapace, stage II larvae and stage IV post-larvae showed the highest and lowest accumulation, respectively. MPF ingestion increased with larval stage and with MPF concentration; under starvation conditions, stage I larvae only ingested them at low MPF concentrations. Oxygen consumption rates were lower only in later larval stages when exposed to high MPF concentrations. Combined, our results indicate that MPF interactions and effects on American lobster larvae are dependent on larval stage, MPF concentration, and presence of food.
Показать больше [+] Меньше [-]Seagrass Cymodocea nodosa and seaweed Ulva lactuca as tools for trace element biomonitoring. A comparative study Полный текст
2020
Bonanno, Giuseppe | Veneziano, Vincenzo | Raccuia, Salvatore Antonino | Orlando Bonaca, Martina
This study compared the capacity of the seagrass Cymodocea nodosa and the green alga Ulva lactuca to sequester the trace elements Cd, Cr, Cu, Ni, Pb and Zn, in seawater and benthic sediments, under the same environmental conditions. Samples of C. nodosa leaves and U. lactuca thalli were collected in four sites off the coast of Sicily (Italy), with varying degrees of anthropogenic impact. C. nodosa accumulated generally higher levels of trace elements, suggesting a better performance in marine phytoremediation. In turn, C. nodosa and U. lactuca showed a similar performance regarding the bioindication of trace elements. Since salinity, temperature and pH had relatively constant values, their role in the accumulation processes in both species should be considered as secondary. Although C. nodosa and U. lactuca fulfill several criteria as bioindicators, including widespread distribution, abundance and tolerance to toxicity, their regular use in biomonitoring programs is still limited.
Показать больше [+] Меньше [-]Microplastics pollution with heavy metals in the aquaculture zone of the Chao Phraya River Estuary, Thailand Полный текст
2020
Ta, Anh Tuan | Babel, Sandhya
Microplastics have received special attention due to their potential risks to environments. However, data on microplastics in estuaries of the Southeast Asian region is still insufficient. This study investigated the abundance and characteristics of microplastics in the sediment and surface water of the Chao Phraya River Estuary, Thailand. Concentrations of heavy metals extracted from microplastics were also reported. The abundance of microplastics in surface water and sediment was 48 ± 8 items/m³ and 39 ± 14 items/kg, respectively. Microplastics with small sizes of 0.05–0.3 mm were predominant in all collected samples. Polypropylene and polyethylene particles were the most abundant in the surface water and sediment, respectively. Toxic metals (Cr, Cu, Ni, Pb, Cd, and Zn) were found in microplastics from surface water samples. Since Chao Phraya River Estuary is an important aquaculture zone in Thailand, the presence of microplastics in this area may severely impact on aquaculture and human health.
Показать больше [+] Меньше [-]Mysterious oil spill along Brazil's northeast and southeast seaboard (2019–2020): Trying to find answers and filling data gaps Полный текст
2020
Lourenço, Rafael André | Combi, Tatiane | Alexandre, Marcelo da Rosa | Sasaki, Silvio Tarou | Zanardi-Lamardo, Eliete | Yogui, Gilvan Takeshi
Large amounts of crude oil were found along Brazil's northeast and southeast seaboard from August 2019 to January 2020. Petroleum companies and oil tankers reported no accidents previously or during this period. The stranded oil on Brazilian beaches looks like tar; it has solid aspect and is denser than seawater. Chemical characterization of this oil showed that light hydrocarbons were still present, increasing the probability of negative effects to coastal organisms and ecosystems upon release in the water column. Diagnostic ratios, chromatogram pattern, and percentage-weathering plots proved that the oil samples share the same oil source. This work provides data for future comparison with oil samples that will likely be found stranded along the Brazilian shoreline in the years to come, helping to understand long term issues associated with the mysterious oil spill that made landfall in late 2019.
Показать больше [+] Меньше [-]Minor and trace elements in skeletons of Arctic echinoderms Полный текст
2020
Iglikowska, A. | Humphreys-Williams, E. | Przytarska, J. | Chełchowski, M. | Kukliński, P.
We report the ratios of minor (K/Ca, Na/Ca, P/Ca, S/Ca) and trace elements (Al/Ca, Ba/Ca, Fe/Ca, Mn/Ca and Zn/Ca) in skeletons of five Arctic echinoderm species representing three classes: Asteroidea, Ophiuroidea, Crinoidea. We found that skeletons of Arctic echinoderms show a unique, species-specific trace element composition that may suggest that incorporation of elements into the skeleton is biologically controlled by the organism. On the other hand, the concentration of some minor elements in skeletal parts exhibit patterns that are consistent with elemental concentrations in seawater, indicating that formation of echinoderm skeletons is environmentally controlled. Seawater is the main source of ions and compounds needed for skeletal formation and maintaining similar concentrations most likely reduces the biological cost related to selective uptake of ions. Additionally, Al, Ba, Fe, Mg and Mn showed station specific variation in elemental concentration which again suggests that accumulation of metals can be shaped by environmental concentrations.
Показать больше [+] Меньше [-]Physical characterization of litter and microplastic along the urban coast of Cagayan de Oro in Macajalar Bay, Philippines Полный текст
2020
Esquinas, Giselle Gina Marie S. | Mantala, Alma P. | Atilano, Marites G. | Apugan, Roan P. | Galarpe, Van Ryan Kristopher R.
There are limited litter and microplastic (MP) studies in the Philippines despite the fact that is has one of the longest shorelines that is possibly threatened by waste disposal. This study was carried out to determine the litter and MP in surface sand samples in a highly urbanized coastal environment of Cagayan de Oro in Macajalar Bay, Philippines. The flotation and stereomicroscope identification methods were employed to study MP, while litters were counted to extrapolate the clean coast index (CCI). Overall, MP fibers were found ubiquitously with site-specific abundance. Particularly, the residential site adjacent to the river mouth had the highest litter and MP fiber counts. The built environment like the seaport showed fragmented forms of MP. Likewise, CCI analysis showed an extremely dirty beachfront (CCI = 85) which mainly caused by plastic litters. Overall, the highly urbanized coastal environment may accumulate a distinct form of plastics. This study is preliminary and may underestimate plastic analysis owing to the limited sampling.
Показать больше [+] Меньше [-]Feeding ecology and microplastic ingestion in Chelon richardsonii (Mugilidae) associated with surf diatom Anaulus australis accumulations in a warm temperate South African surf zone Полный текст
2020
McGregor, Steven | Strydom, Nadine Amelia
The study aimed to explore ontogenetic dietary changes and microplastic ingestion in Chelon richardsonii associated with diatom Anaulus australis accumulations in a warm temperate South African surf zone. This species is commercially important and forms an important trophic link in southern African coastal waters. Postflexion larvae, juveniles and adults are dominant in surf zones and were used for comparison. Index of Relative Importance (%IRI) results showed an ontogenetic dietary shift, with postflexion larvae ingesting mostly copepods (%IRI = 52.0) and microplastic fibres (%IRI = 30.7); while older developmental stages fed predominantly on diatoms (%IRI ranging from 53.9 to 65.6) and sand (%IRI ranging from 34.2 to 46.0). Microplastic fibres were found in 40% of fish sampled, microplastic fragments in 5%, and both types were recorded across all developmental stages assessed. This study provides the first record of microplastics in C. richardsonii, adding to growing microplastic research in fishes.
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