Уточнить поиск
Результаты 2231-2240 из 7,290
Managing beyond ecosystem limits at the land-sea interface: The case of sandy beaches Полный текст
2022
Jorge-Romero, Gabriela | Elliott, Michael | Defeo, Omar
Sandy beaches are part of an integral social-ecological system whose management has to encompass the natural and societal features of the catchment and the adjacent marine area, as well as the beach itself. Using a multi-use and complex beach system in Uruguay, the La Coronilla and Barra del Chuy resort, we interrogate those natural and societal features by employing the DAPSI(W)R(M) cause-consequence-response cycle and pathways. This identifies the Drivers, Activities, Pressures, State change on the natural system, Impacts (on the Welfare of the human system), and the Responses (requiring management Measures). We contend that this approach is needed for the sustainable development and use of this ecosystem and its biodiversity protection. This also indicates the importance of a holistic and systems approach, which is necessary, valid and valuable for sandy beaches worldwide.
Показать больше [+] Меньше [-]Operationalizing the Exposome Using Passive Silicone Samplers Полный текст
2022
Fuentes, Zoe Coates | Schwartz, Yuri Levin | Robuck, Anna R. | Walker, Douglas I.
The exposome, which is defined as the cumulative effect of environmental exposures and corresponding biological responses, aims to provide a comprehensive measure for evaluating non-genetic causes of disease. Operationalization of the exposome for environmental health and precision medicine has been limited by the lack of a universal approach for characterizing complex exposures, particularly as they vary temporally and geographically. To overcome these challenges, passive sampling devices (PSDs) provide a key measurement strategy for deep exposome phenotyping, which aims to provide comprehensive chemical assessment using untargeted high-resolution mass spectrometry for exposome-wide association studies. To highlight the advantages of silicone PSDs, we review their use in population studies and evaluate the broad range of applications and chemical classes characterized using these samplers. We assess key aspects of incorporating PSDs within observational studies, including the need to preclean samplers prior to use to remove impurities that interfere with compound detection, analytical considerations, and cost. We close with strategies on how to incorporate measures of the external exposome using PSDs, and their advantages for reducing variability in exposure measures and providing a more thorough accounting of the exposome. Continued development and application of silicone PSDs will facilitate greater understanding of how environmental exposures drive disease risk, while providing a feasible strategy for incorporating untargeted, high-resolution characterization of the external exposome in human studies.
Показать больше [+] Меньше [-]Spatiotemporal evaluation of water quality and risk assessment of heavy metals in the northern Caspian Sea bounded by Kazakhstan Полный текст
2022
Ramazanova, Elmira | Bahetnur, Yingkar | Yessenbayeva, Kadisha | Lee, Seung Hwan | Lee, Woojin
The water quality of the northern Caspian Sea has not been well-known, and its contamination can adversely affect the health of swimmers and seashore residents. The study sought to determine the contamination state of the Caspian Sea in Kazakhstan and quantify human health risks coming from the existing heavy metals concentration. The Caspian Sea was found to be “fairly to marginally” contaminated (24 < CCME-WQI < 64), with Cd influencing the index significantly. Concentrations of Cd and Pb increase over time (seasonal Kendall test, p-values = 2–4 %) in sites near oil fields and ports, suggesting the significant role of anthropogenic sources in causing diverse pollution events. Pb demonstrated the highest variability and number of outliers (4.3 % of all samples with coefficients of variation reaching up to 175 %). The principal component analysis further revealed that various discharges from oilfields and upstream transport could contribute to the contamination by heavy metals and their concentrations. Contamination is associated with up to 6 % cancer risk for adults. The long exposure duration of swimmers in water increases risks by up to 18 %, indicating the local population is at a higher risk. In conclusion, statistical tests and analysis indicate the presence of anthropogenic sources, and risk assessment reveals swimming can contribute to cancer risk.
Показать больше [+] Меньше [-]Oxidative stress, apoptosis, and transcriptional responses in Acropora microphthalma under simulated diving activities Полный текст
2022
Zhang, Yu | Chen, Rou-Wen | Liu, Xiangbo | Zhu, Ming | Li, Zhuoran | Wang, Aimin | Li, Xiubao
This study simulated the effects of diving activities on the physiology, enzymatic, and transcriptional responses of Acropora microphthalma. Touching had less impact on Fv/Fm, but a few zooxanthellae were decreased and minor MDA was elevated. Caspase 3 was activated to remove damaged cells, and SOD was increased to alleviate oxidative damage. Under double or triple diving stress, we observed mass loss of zooxanthellae and Fv/Fm, a significant increase in MDA, and SOD, CAT was activated in response to oxidative stress. Transcriptome analyses showed that corals activated immune signaling pathways, anti-oxidation pathways, lysosomal, phagosomal, and cellular autophagy pathways to manage oxidation stress. Moreover, it up-regulated carbohydrate metabolisms, as well as lipopolysaccharide metabolism, glycosphingolipid biosynthesis, photorespiration, amino acid metabolism, and fatty acid beta-oxidation, but down-regulated fatty acid biosynthesis to answer energy insufficiency. This research supported that even in a short time, improper diving activities could have a serious impact on coral health.
Показать больше [+] Меньше [-]Variability of trace metals in coastal and estuary: Distribution, profile, and drivers Полный текст
2022
Harmesa, | Wahyudi, A'an Johan | Lestari, | Taufiqurrahman, Edwards
Ongoing global changes such as increasing sea-surface temperatures, decreasing acidity levels, and expanding oxygen-minimum zone may impact on the biogeochemical cycles of trace metals in ocean systems. Each trace metal has unique characteristics and a distinctive distribution pattern controlled by chemical, biological, and physical processes that occur in ocean systems. The correlations of variability drivers in trace metals are interesting topics for investigation. Following up on ocean research in the coastal and estuary area, we specifically review the distribution of trace metals in seawater and suspended and surface sediment. The marginal seas usually feature significant terrestrial inputs accompanied by several active water-mass currents. The purpose of this review is to provide an overview of variability related to trace-metal distribution in coastal and estuary systems and to specifically describe the distribution, profile and drivers that affect trace metals variability.
Показать больше [+] Меньше [-]Distribution, source identification and environmental risk assessment of potentially toxic elements (PTEs) in the surface sediment of Sanmen Bay, Zhejiang Province, China Полный текст
2022
Wang, Weili | Lin, Cai | Jiang, Ronggen | Liu, Yang | Sun, Xiuwu | Lin, Hui | Chen, Jinmin
In this paper, the distribution, degree of pollution and sources of Cu, Pb, Zn, Cd, Cr, As, Co, Ni and Hg in the surface sediment of Sanmen Bay were studied. The average concentrations of the identified potentially toxic elements (PTEs) were in the following order: Zn > Ni > Cr > Cu > Pb > Co > As>Cd > Hg. Almost all PTEs had a significant positive correlation with TOC, clay and Al; Cr had no significant correlations. Apart from Hg, the contamination levels of 8 PTEs were at those considered to be low-to-no pollution. Comparatively, the contamination level of Hg was much higher than the background value, which indicated moderate pollution. The source of this pollution may have included industrialization, urbanization and/or transport of industrial waste materials. Both geoaccumulation index (Igₑₒ) and potential ecological risk (RI) values suggested that Hg was the major contributor to the ecological risk posed by the selected PTEs.
Показать больше [+] Меньше [-]Effects of pile driving sound playbacks and cadmium co-exposure on the early life stage development of the Norway lobster, Nephrops norvegicus Полный текст
2022
Stenton, C.A. | Bolger, E.L. | Michenot, M. | Dodd, J.A. | Wale, M.A. | Briers, R.A. | Hartl, M.G.J. | Diele, K.
There is an urgent need to understand how organisms respond to multiple, potentially interacting drivers in today's world. The effects of the pollutants anthropogenic sound (pile driving sound playbacks) and waterborne cadmium were investigated across multiple levels of biology in larval and juvenile Norway lobster, Nephrops norvegicus under controlled laboratory conditions. The combination of pile driving playbacks (170 dBₚₖ₋ₚₖ re 1 μPa) and cadmium combined synergistically at concentrations >9.62 μg[Cd] L⁻¹ resulting in increased larval mortality, with sound playbacks otherwise being antagonistic to cadmium toxicity. Exposure to 63.52 μg[Cd] L⁻¹ caused significant delays in larval development, dropping to 6.48 μg[Cd] L⁻¹ in the presence of piling playbacks. Pre-exposure to the combination of piling playbacks and 6.48 μg[Cd] L⁻¹ led to significant differences in the swimming behaviour of the first juvenile stage. Biomarker analysis suggested oxidative stress as the mechanism resultant deleterious effects, with cellular metallothionein (MT) being the predominant protective mechanism.
Показать больше [+] Меньше [-]Benthic impact assessment of a dredge sediment disposal in a dynamic resilient environment Полный текст
2022
Dauvin, Jean-Claude | Baux, Noémie | Lesourd, Sandric
The eastern part of the Bay of Seine (English Channel) is highly impacted by harbour activities and the dumping of dredged sediment by the port authorities of Le Havre (GPMH) and Rouen (GPMR). Sediment dredged by the GPMH (2–2.5 millions of m³ per year) has been disposed at the subtidal Octeville site since 1947. Since the 2000s, mainly fine sediment (80% of fine particles <63 μm) has been disposed using alternate mosaic boxes with limited thickness (0.2 to 0.6 m per box per year), preventing the accumulation of disposed sediment in some parts of the dumping site. During the period August 2016 to September 2017, an experimental study was set up to identify the spatio-temporal changes of the macrobenthos collected at ten stations on six dates: three stations where different volumes of sediments were dumped (from 41,000 to 186,000 m³), two stations located within the Octeville site but without dumping operations during the study and five stations outside the disposal site (northern and southern zones). The Taxonomic Richness, total abundance and abundances of the polychaete Owenia fusiformis show negative correlations with the volumes of deposited sediment, whereas use of the AMBI (AZTI's Marine Biotic Index) and B2OA (Benthic Opportunist Annelids Amphipods) indices does not allow us to distinguish the impacted zone. Our study shows that the impact of dumping remains local and the benthic habitats display a high degree of resilience with rapid recovery of the community after the cessation of disturbance. Recommendations on the future long-term strategy are proposed to improve assessment and minimise the impact of dumping sediment on this benthic habitat.
Показать больше [+] Меньше [-]Spatial and temporal trends of polycyclic aromatic hydrocarbons in sediment cores of Brunei Bay, East Malaysia Полный текст
2022
Pang, Swee Yun | Suratman, Suhaimi | Tay, Joo Hui | Tan, Hock Seng | Mohd Tahir, Norhayati
The spatial and temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in three sediment cores from Brunei Bay, Southern South China Sea was investigated. The total concentrations of 16 priority PAHs (∑PAH₁₆) and their alkyl-substituted derivatives ranged from 10.4 to 376 ng g⁻¹ and 30.7 to 2263 ng g⁻¹, respectively. PAH biomarker diagnostic ratios and principal component analysis (PCA) combined with absolute principal component score (APCS) and multiple linear regression (MLR) were performed to apportion the source contribution. The results revealed mixed inputs of fuel combustion residues and uncombusted petrogenic products. The downcore PAH profile revealed that the highest peaks could be related to past human activities using biofuel and coal during the industrialization/agriculture revolution period. The 1,7/(2,6+1,7)-dimethylphenanthrene ratio also highlighted wood combustion during forest fire outbreaks, which appeared to coincide with the past climate events.
Показать больше [+] Меньше [-]Mercury contamination of sediments in an open coastal area of the Hupo Basin, East Sea, Korea Полный текст
2022
Joe, Dong Jin | Choi, Man Sik | Um, In Kwon | Choi, Seong Hu | Park, So Jung
Mercury (Hg) contamination in open coastal areas has attracted public concern regarding safe fish consumption and management of the coastal environment, especially in areas of accidental Hg spills on inland coasts. This study investigated the temporal and spatial distribution of Hg in sediments of Youngil Bay and the Hupo Basin, East Sea, Korea; it also discussed the sources and transport of anthropogenic Hg. Hg hot spots were found in the northern Hupo Basin (elevated by 2–3×) and the river mouth area in Youngil Bay (elevated by approximately 70×). The river mouth contamination resulted from the destruction of a dam impounding landfill waste, while the basin contamination was attributed to atmospheric deposition and Hg enrichment associated with increased organic carbon concentrations driven by high biological production in the coastal upwelling area. Spilled Hg was transported to open coastal areas up to 36.6°N.
Показать больше [+] Меньше [-]