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A feedback-controlling digital microfluidic fluorimetric sensor device for simple and rapid detection of mercury (II) in costal seawater Full text
2019
Zhang, Qian | Zhang, Xingcai | Zhang, Xiaolin | Jiang, Lan | Yin, Jingmei | Zhang, Peng | Han, Shuang | Wang, Yunhua | Zheng, Guoxia
By combination of miniaturization potential of digital microfluidics (DMF) and sensitivity of fluorescence probe, an integrated sensor device has been initially constructed for mercury detection in coastal waters. The actuation feature of the detecting target, seawater droplet, which remains unclear, was basically explored. To overcome a potential risk of driven failure, induced by diversity ion ingredients in seawater, a feedback control loop was included into control system. Analyzing method for coastal waters was well established on DMF, which showed satisfied stability and selectivity in Hg sensing under high salinity condition, with the sensitivity of Hg²⁺ at the parts per billion level and total testing time less than 20s. With the advantages of being fast, amenable to automation and low cost, this device is promising for the formation of simple and rapid sensor device, especially for a routine monitoring and emergency detection of Hg/or other metals in coastal waters.
Show more [+] Less [-]Response planning for accidental oil spills in Persian Gulf: A decision support system (DSS) based on consequence modeling Full text
2019
Amir-Heidari, Payam | Raie, Mohammad
Different causes lead to accidental oil spills from fixed and mobile sources in the marine environment. Therefore, it is essential to have a systematic plan for mitigating oil spill consequences. In this research, a general DSS is proposed for passive and active response planning in Persian Gulf, before and after a spill. The DSS is based on NOAA's advanced oil spill model (GNOME), which is now linked with credible met-ocean datasets of CMEMS and ECMWF. The developed open-source tool converts the results of the Lagrangian oil spill model to quantitative parameters such as mean concentration and time of impact of oil. Using them, two new parameters, emergency response priority number (ERPN) and risk index (RI), are defined and used for response planning. The tool was tested in both deterministic and probabilistic modes, and found to be useful for evaluation of emergency response drills and risk-based prioritization of coastal areas.
Show more [+] Less [-]Differential toxicity of functionalized polystyrene microplastics to clams (Meretrix meretrix) at three key development stages of life history Full text
2019
Luan, Liping | Wang, Xiao | Zheng, Hao | Liu, Liuqingqing | Luo, Xianxiang | Li, Fengmin
Little knowledge is available on impact of microplastics (MPs) on the bivalve larvae at different developmental stages throughout their life history, especially for metamorphic stage. Therefore, this study aims to evaluate the toxic responses of carboxylated (PS-COOH) and amino (PS-NH2) polystyrene MPs on the developing clam larvae at three key life stages, i.e., fertilized eggs, D-veliger larvae, and umbo larvae. PS-COOH and PS-NH2 significantly decreased the hatching rates by 5.79–39.5% and developmental rates by 4.78–7.86% of the clam larvae relative to the unexposed clam larvae. The toxicity of MPs followed the order: hatching stage > metamorphosis > D-veliger larvae stage, showing stage-dependent toxic effects. Moreover, PS-NH2 with a smaller hydrodynamic diameter showed a greater toxicity to the developing larvae compared to PS-COOH. Our study highlighted the stage-dependent toxic effects of MPs on the developing clam larvae, thus posing ecological risks to population succession of marine bivalves and aquatic ecosystems.
Show more [+] Less [-]Elemental geochemistry in acid sulphate soils – A case study from reclaimed islands of Indian Sundarban Full text
2019
Ghosh, Somdeep | Bakshi, Madhurima | Mitra, Shubhro | Mahanty, Shouvik | Ram, Shidharth Sankar | Banerjee, Shamayita | Chakraborty, Anindita | Sudarshan, M. | Bhattacharyya, Subarna | Chaudhuri, Punarbasu
Sundarban along with its networks of rivers, creeks and magnificent mangroves form a unique ecosystem. Acid sulphate soils have developed in this ecosystem under anoxic reducing conditions. In the present study, we have investigated the distribution of acid sulphate soils along with its elemental characterization and possible sources in four reclaimed islands of Indian Sundarban like Maushuni (I1), Canning (I2), Bally (I3) and Kumirmari (I4). Elements show moderate to strong correlation with each other (P < 0.01; P < 0.05). Except Si, Ca and Pb, a higher enrichment factor was observed for K, Cr, Mn, Fe, Ni, Cu and Zn. Geo-accumulation index values of all sampling locations reveal that Cr, Fe, Cu and Zn are in Igₑₒ class 1. The pollution load index value of the reclaimed islands of Indian Sundarban varies between 1.31 and 1.48. The observation of this study could help to strategize policies to mitigate and manage acid sulphate soils in Indian Sundarban.
Show more [+] Less [-]Building evidence around ghost gear: Global trends and analysis for sustainable solutions at scale Full text
2019
Richardson, Kelsey | Asmutis-Silvia, Regina | Drinkwin, Joan | Gilardi, Kirsten V.K. | Giskes, Ingrid | Jones, G. (Gideon) | O'Brien, Kevin | Pragnell-Raasch, Hannah | Ludwig, Laura | Antonelis, Kyle | Barco, Susan | Henry, Allison | Knowlton, Amy | Landry, Scott | Mattila, David | MacDonald, Kristen | Moore, Michael | Morgan, Jason | Robbins, Jooke | van der Hoop, Julie | Hogan, Elizabeth
Abandoned, lost or discarded fishing gear (ALDFG) comprises a significant amount of global marine debris, with diverse impacts to marine environments, wildlife, and the fishing industry. Building evidence on ALDFG is critical to holistically understand the marine debris issue, and to inform the development of solutions that reduce amounts of ALDFG sources and recover existing gear. Substantial work has been and continues to be undertaken around the world to collect data on ALDFG, much of which remains unpublished. To provide a global picture of data on ALDFG, we organized a technical session that brought together seven ALDFG leaders to share their expertise in data collection, retrieval, and awareness-raising. This paper summarizes the technical session to highlight: 1) case studies that feature innovative approaches to ALDFG data collection and retrieval; 2) examples of opportunities to fill data gaps and improve our understanding of wildlife ingestion of and entanglement in ALDFG; and 3) awareness-raising through the development of a publicly accessible global ALDFG database.
Show more [+] Less [-]Health Effects of Climate Change Through Temperature and Air Pollution Full text
2019
Lou, Jianing | Wu, Yangyang | Liu, Penghui | Kota, Sri Harsha | Huang, Lei
PURPOSE OF REVIEW: Recognizing health effects of changes in temperature caused by climate change and changes in air pollution affected by temperature changes on human health, predicting the health effects of both future temperature changes and air quality changes caused by climate change is critical to adopting a range of measures to respond to future climate change. The purpose of this review is to summarize studies on the health effects of temperature and air quality changes affected by climate change directly or indirectly, and to summarize the limitations of these studies. RECENT FINDINGS: After summarizing the main methods and results, we conclude that past temperature changes and air pollution caused by climate change directly or indirectly have a serious impact on the mortality or morbidity of human diseases, and climate change does impact human health and will exacerbate these effects. Moreover, it may have spatial and socioeconomic differences in the world. Nonetheless, these studies also indicate that policies about climate change and emission reduction can reduce these effects. The evaluation focuses on the interaction between temperature change and air quality caused by climate change and assesses the impact of both on human health. There are still some uncertainties in existing research, and future health predictions related to climate change should focus on quantitative exploration of temperature and air pollution changes, eliminate interference caused by factors such as industrialization, and demographic changes, while the choice of meteorological conditions should be further extended, not just limited to the temperature and air quality.
Show more [+] Less [-]Benthic foraminifera as potential ecological proxies for environmental monitoring in coastal regions: A study on the Beypore estuary, Southwest coast of India Full text
2019
Sreenivasulu, G. | Praseetha, B.S. | Daud, Nurul Rabitah | Varghese, Tiju I. | Prakash, T.N. | Jayaraju, N.
The benthic foraminiferal diversity index was computed from Beypore estuary sediments. The abundance and diversity of Quinqueloculina lata, Textularia agglutinans, Haplophagmoides canariensis, and Quinqueloculina stelligera were dominated by stress-tolerant taxa such as Ammonia tepida, A.parkinsoniana, Nonion grateloupi, and N. scaphum in the estuary. The small-size foraminifera probably perished in a juvenile stage because of the high temperature and low salinity that prevailed in the ecosystem. The dominance of stress tolerant benthic foraminifera and absence of Elphidium species in the estuary suggest the prevalence of hypoxic (low-oxygen) conditions. The consistent low-diversity index of foraminifera indicates that the ecosystem is moderate to highly stressed ecologically in the Beypore estuary. The application of benthic foraminifera as a bioindicator for assessing the environmental stress in the Beypore estuary is key in monitoring these fragile coastal ecosystems.
Show more [+] Less [-]Spatiotemporal distributions of halocarbons in the marine boundary air and surface seawater of the Changjiang estuary and its adjacent East China Sea Full text
2019
Yuan, Da | He, Zhen | Yang, Gui-Peng
Spatiotemporal distributions of volatile halogenated organic compounds (VHOCs) were investigated in the marine boundary air and surface seawater of the Changjiang (Yangtze River) estuary and its adjacent East China Sea in two cruises from March 11, 2015 to March 21, 2015 and from July 9, 2015 to July 20, 2015. Results revealed that the concentrations of released chlorofluorocarbons (CFCs) such as CFC-12, CFC-11, and CFC-114 in China decreased, suggesting that limitations set by the Chinese government on CFCs production and consumption have taken effect. Atmospheric concentrations of CFCs were affected by local industrial sources of emission and transport of terrestrial pollutants from coastal areas to varying degrees. Seasonal variations in atmospheric VHOCs were probably due to seasonal differences in prevalent monsoon and biogenic production. In the study periods, the investigated area was an essential source of atmospheric CH3Br and CH3I but was a net sink of CFC-12, CFC-11, and CH3Cl.
Show more [+] Less [-]Accumulation and distribution of marine debris on barrier islands across the northern Gulf of Mexico Full text
2019
Wessel, Caitlin | Swanson, Kathleen | Weatherall, Tracy | Cebrian, Just
Marine debris is an economic, environmental, human health, and aesthetic problem posing a complex challenge to communities around the globe. To better document this problem in the Gulf of Mexico we monitored the occurrence and accumulation rate of marine debris at twelve sites on nine barrier islands from North Padre Island, Texas to Santa Rosa, Florida. With this information we are investigating three specific questions: (1) what are the major types/sources of marine debris; (2) does debris deposition have seasonal oscillations; and (3) how does debris deposition change spatially? Several trends emerged; plastic composed 69–95% of debris; there was a significant increase in debris accumulation during the spring and summer seasons; accumulation rates were ten times greater in Texas than the other Gulf States throughout the year; and the amount of debris accumulating along the shoreline could be predicted with high confidence in areas with high freshwater influx.
Show more [+] Less [-]Effects of the installation of offshore pipelines on macrozoobenthic communities (northern and central Adriatic Sea) Full text
2019
Spagnolo, A. | Cuicchi, C. | De Biasi, A.M. | Ferrà, C. | Montagnini, L. | Punzo, E. | Salvalaggio, V. | Santelli, A. | Strafella, P. | Fabi, G.
Macrozoobenthos living around several pipelines placed at different depths and sediment types in the Western Adriatic Sea was investigated for three years after structures' deployment to detect possible effects due to their installation and presence. Three environmental habitats were considered based on the grain size (silty clay, clayey silt and sand). Samplings were taken within a radius of 100 m from the pipelines and at control sites. Multivariate and univariate analysis showed peculiarities of the three habitats due to the different sediment type, without differences between pipelines and controls inside each group. Silty clay and clayey silt communities appeared quite similar, being mainly represented by opportunistic species typical of the Adriatic coastal area. Benthic populations found at the offshore relict sand were characterized by a higher percentage of sensitive species. Independently of sediment typology, pipelines' installation seems to not affect the benthic populations that appear more influenced by environmental features.
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