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Differential coral response to algae contact: Porites tissue loss, praise for Halimeda interaction at southeast coast of India Full text
2019
Thinesh, Thangadurai | Jose, Polpass Arul | Ramasamy, Pasiyappazham | Meenatchi, Ramu | Selvan, K Muthamizh | Selvin, Joseph
Worldwide, reef building corals are being degraded due to increasing anthropogenic pressure, and as a result, macroalgal cover is being increased. Hence, mechanism of coral–algal interaction, differential coral response to algal overgrowth, is critical from every geographical location to predict future coral dynamics. This paper documents the frequency of coral–algal (Halimeda) interactions, differential coral response to algal interaction. We found difference in susceptibility among coral genera to competitive effects. Out of 970 coral colonies surveyed, 36.7% were in contact with Halimeda sp. Most frequent contact was observed in Porites (57%) followed by Favites 28% (n = 60), Acropora 26% (n = 48), Platygyra 5% (n = 5) and Symphyllia 4.2% (n = 3). Frequent discoloration and tissue loss were only observed in Porites. Continuous monitoring revealed that long-term algal physical contact prevents light required for polyp for photosynthesis and stops coral feeding ability. In this study, we also found mutual exclusion between Halimeda and coral recruit. Out of 180 coral colonies (size class between 5 and 15 cm) comprised of Favites (n = 74), Acropora (n = 20), Favia (n = 79) and Porites (n = 7) surveyed, none of them were found in Halimeda-dominated sites. The documented effects of recruitment exclusion and tissue mortality followed by algal interaction on major reef building corals (Porites) could affect replenishing process and health of the remaining healthy corals in the Palk Bay reef if algal proliferation rate is not controlled through proper management strategies.
Show more [+] Less [-]New Optical Tools for Water Quality Diagnostics Full text
2019
Varotsos, Costas A. | Krapivin, Vladimir F. | Mkrtchyan, Ferdenant A.
New optical tools are proposed for the real-time diagnosis of water quality without traditional sampling and laboratory physico-chemical analysis. In particular, the optical decision-making system is developed as an operational tool for in-situ assessment of water quality in natural water areas. Specifically, three versions of this system are analyzed using 8-channel and 35-channel photometric devices and a 128-channel spectroelipsometric device. The spectral images obtained from these devices are the basis for the diagnosis of water quality by using new algorithms to detect these spectral images. In more detail, four algorithms are developed to identify optical spectral images of water objects. The effectiveness of these optical tools is demonstrated in experimental water quality control sites in water systems operating under different climatic conditions. Finally, the results for the determination of the various pollutants at the surface of these water bodies are presented.
Show more [+] Less [-]Dispersion of Gravel Road Fine-Fractions as Influenced by Oil-Well Produced Water and Simulated Solutions of Various SAR, EC, and Ca/Mg Ratios Full text
2019
Graber, Kayla | Hargiss, Christina L. M. | DeSutter, Thomas | He, Yangbo | Norland, Jack E.
In the northern Great Plains, a potential road dust abatement is the application of oil-well produced water, also known as “brine.” However, little is known about the effectiveness of brine or its potential impacts on dispersion of road materials and the creation of dusts. This study aimed to investigate how sodium adsorption ratios (SAR), electrical conductivity (EC), and Ca/Mg ratios of simulated and non-simulated brine influenced dispersive reactions of three mineralogically different gravel road fine fractions. Ca/Mg ratios had little to no significant influence on the outcome of dispersion. Irrespective of the SAR or clay mineralogy, a threshold EC of 4 dS m⁻¹ was sufficient to control road fine fraction dispersion. Actual oil-well produced water effect on dispersion followed the same order as that treated by simulated solution and the dispersion value can be well-predicted from EC. This information is useful to managers, regulators, scientists, and industry professionals considering the use of brine as a road dust control abatement.
Show more [+] Less [-]Native Plants for Revegetation of Mercury- and Arsenic-Contaminated Historical Mining Waste—Can a Low-Dose Selenium Additive Improve Seedling Growth and Decrease Contaminant Bioaccumulation? Full text
2019
Chapman, E. Emily V. | Moore, Christine | Campbell, Linda M.
Highly contaminated exposed legacy gold mine tailings from the late 1800s are present in many locations throughout North America and other parts of the world that experienced gold rushes at that time. Those tailing fields can pose risks to human health and the environment. Revegetation of tailing fields can reduce dust generation and other risks associated with these sites. The objective of this study was to investigate if native rapid-growing plants could be successfully germinated in mercury (Hg) and arsenic (As) contaminated legacy mine tailings, both untreated and treated with a low dose of sodium selenite (Na₂SeO₃) to promote growth and decrease bioaccumulation of contaminants. After screening many candidates, four wide-spread North American native plant species were selected, Juncus tenuis, Anaphalis margaritacea, Symphotrichum novi-belgii, and Panicum virgatum for their tolerance, presence near legacy gold mine sites, and ability to germinate rapidly in harsh conditions. Three of these species germinated and grew well in untreated tailings except for S. novi-belgii. The selenite treatment increased biomass, emergence, shoot height, and root length in J. tenuis; emergence in A. margaritacea; and root lengths in P. virgatum. This treatment also decreased shoot [Hg] and [As] in P. virgatum by 36% and 40%. Low-dose selenite treatments hold promise for supporting germination and growth of native plants in Hg- and As-contaminated tailing fields.
Show more [+] Less [-]Applicability of Coal Bottom Ash from Thermoelectric Power Plant as an Alternative Heterogeneous Catalyst in Photo-Fenton Reaction Full text
2019
Drumm, Fernanda Caroline | Grassi, Patrícia | Sulkovski, Aline Alexia | Franco, Dison Stracke Pfingsten | Georgin, Jordana | Dotto, Guilherme Luiz | Foletto, Edson Luiz | Jahn, Sérgio Luiz
In this work, coal bottom ash, a residue generated in thermoelectric power plant, was employed as an alternative catalyst in photo-Fenton reaction for the degradation of sunset yellow dye from liquid solution under visible irradiation. The residue was characterized by techniques such as XRD, XRF, N₂ adsorption/desorption isotherms, SEM/EDS, and FT-IR. The influence of reaction parameters such as solution pH, catalyst dosage, and H₂O₂ concentration on dye removal was analyzed by a central composite rotatable design 2³. According to the characterization results, the presence of iron in the material was confirmed by analysis of chemical composition by XRF, presenting 5.5 wt% in terms of iron oxide. Through the response surface methodology, it was possible to adjust the polynomial model and determine the optimum region of dye removal. The regression model was predictive and significant, with a coefficient of determination (R²) equivalent to 91%, showing a good fit between the experimental and theoretical values. The optimum region reaching a color removal of 91% has a pH level of 2.7, catalyst dosage of 0.9 g L⁻¹, and H₂O₂ concentration of 10 mmol L⁻¹. Therefore, coal bottom ash, an abundant residue with low cost, showed to be a potential catalyst in a photo-Fenton process for the removal of organic contaminant from liquid solution.
Show more [+] Less [-]Concentrations of cadmium and lead, but not zinc, are higher in red fox tissues than in rodents—pollution gradient study in the Małopolska province (Poland) Full text
2019
Ziętara, Joanna | Wierzbowska, Izabela A. | Gdula-Argasińska, Joanna | Gajda, Agnieszka | Laskowski, Ryszard
The main purpose of our research was to assess the chronic exposure of red foxes to Cd, Pb and Zn. We have determined concentrations of these metals in the kidney, liver and muscle of 36 red foxes hunted between December 2002 and March 2003 in differently polluted areas in southern Poland. Tissue concentrations of Pb and Cd in the red foxes significantly co-varied with concentrations of these elements in the soil, and differed between the tissues. We compared concentrations of Pb, Cd, and Zn in red foxes with two rodent species, Apodemus flavicollis and Myodes glareolus, trapped simultaneously in the same area. Concentrations of Pb and Cd appeared significantly higher in the red foxes than in the rodents, but the slopes of the relationship between metal concentrations in tissues and in soil were similar in all species. This indicates that extrapolation from results of monitoring studies conducted on rodents to mammalian carnivores is possible but requires applying an extrapolation factor.
Show more [+] Less [-]Silicon-mediated role of 24-epibrassinolide in wheat under high-temperature stress Full text
2019
Hussain, Muzaffer | Khan, Tanveer Alam | Yusuf, Mohammad | Fariduddin, Qazi
High temperature poses a severe extortion to productivity of many crops like wheat. Therefore, well documented roles of brassinosteroid (BR) and silicon (Si) in terms of abiotic stress tolerance, the current study was designed to evaluate the response of wheat (Triticum aestivum L. Var. PBW-343) to 24-epibrassinolide (EBL) mediated by silicon grown under high temperature stress. At 10- and 12-day stage after sowing, the seedlings were administered Si (0.8 mM) through the sand, and the plants at 20, 22, or 24 days after sowing (DAS) were given EBL (0.01μM) through foliage. Plants were treated to high-temperature stress (35/28 or 40/35 °C), for 24 h with 12-h photoperiod in plant growth chamber at 25- and 26-day stage of growth. High temperatures cause significant reduction in growth performance and photosynthesis-related attributes at 35 days after sowing. However, antioxidant enzymes and proline content also augmented substantially with increasing temperature. BR and Si enhanced antioxidant activity and proline content, which was earlier increased by the high temperature. It is established that interaction of EBL and Si considerably improved the growth features, photosynthetic efficacy, and several biochemical traits under high-temperature stress through elevated antioxidant system and osmoprotectant.
Show more [+] Less [-]Environmental exposure and health effects in a highly polluted area of Northern Italy: a narrative review Full text
2019
Alias, Carlotta | Benassi, Laura | Bertazzi, Luca | Sorlini, Sabrina | Volta, Marialuisa | Gelatti, Umberto
Human health and well-being are strongly linked to the state of the environment. The high industrial pressure present in the Province of Brescia, located in Northern Italy, produced strong environmental and health concerns. This narrative review of the literature aims at identifying the studies focused on the association between exposure to environmental pollutants and health effects in the population living in this area. Thirteen papers fitted the inclusion criteria: five were focused on the connection among pollutants present in air matrix and health effects, seven on both air and soil, and one on soil. No study investigated the relationship with water pollution. The great variability in the analyzed end-points made it difficult to draw precise conclusions, but the fact that, in almost all the studies, the investigated health effects have a positive association with the exposure to different kinds of pollutants, allows us to hypothesize that the considered population is living in an area where the “environmental pressure” could produce significant health effects in the future.
Show more [+] Less [-]RETRACTED ARTICLE: Immobilization of Heavy Metals in e-Waste Contaminated Soils by Combined Application of Biochar and Phosphate Fertilizer Full text
2019
Huang, Ling | Liu, Chong | Liu, Xiaowen | Chen, Zhiliang
This paper reports the effects of single and combined application of biochar and phosphate fertilizer on immobilization of heavy metals in e-waste-contaminated soils. The results showed that combined amending biochar and phosphate fertilizer improved physical and chemical characteristics of soil but resulted in ammonium nitrogen loss. Biochar combined with phosphate fertilizer increased shoot biomass of lettuce while biochar applied alone could inhibit the growth of lettuce. A distinct decrease of heavy metal concentrations in lettuce was observed in phosphate fertilizer + biochar (3.0%) treatments while highest heavy metal concentrations in shoots and roots were observed in control treatments. In phosphate fertilizer (0.8%) + biochar (3.0%) treatment, Cd, Cu, Pb, and Zn concentrations of lettuce leaf were reduced by 34.78%, 29.37%, 46.59%, and 40.95%, respectively. Biochar + phosphate fertilizer and biochar both reduced bioconcentration of Cd, Cu, Pb, and Zn in different tissues of lettuce while transshipment of Cd, Cu, Pb, and Zn from root to shoot increased after combined amendment of biochar with phosphate fertilizer. Application of phosphate fertilizer + biochar enhanced the immobilization of Cd, Cu, Pb, and Zn by decreasing the exchangeable Cd, Cu, Pb, and Zn in the soil. Precipitation, adsorption, ionic exchange, and chelation contributed to the good immobilization capacity of biochar + phosphate fertilizer on Cd, Cu, Pb, and Zn in e-waste-contaminated soils.
Show more [+] Less [-]Tea Residue Boosts Dye Decolorization and Induces the Evolution of Bacterial Community Full text
2019
Xie, Xuehui | Zheng, Xiulin | Yu, Chengzhi | Zhang, Qingyun | Wang, Yiqin | Cong, Junhao | Liu, Na | He, Zhenjiang | Yang, Bo | Liu, Jianshe
Considerable researches on removal of azo dyes have been reported in recent years, but few researchers have documented adsorption and/or transformation of anthraquinone dyes by physical, chemical, or biological treatment methods due to their fused aromatic structures. In this study, tea residue was found to have significant enhancement effect on the decolorization of anthraquinone dye reactive blue 19. This effect worked on different dye decolorizing bacterial florae and the natural bacterial flora from surface water and exhibited universal feature. Six single bacterial strains were isolated from bacterial flora DDMY2. Unexpectedly, all of them had poor decolorization capacity. High-throughput sequencing results revealed the community evolution of bacterial flora DDMY2 cultured with tea residue after 6 months and 12 months. It was found that the community structure changed dramatically because the influence of tea residue and the dominant functional genera, such as unclassified_o_Pseudomonadales, Stenotrophomonas, Bordetella, and Brevibacillus, was significantly enriched. Meanwhile, the evolved community structure could keep stable for a long time, resulting in the decolorization effect stabilized for a long time. This study provides the tea residue as the bioactivator that can be applied to boost the decolorization of dyes by various potential bacterial florae. It also enlarges our knowledge of making full use of biowaste in biological wastewater treatment.
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