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Biochemical and Physiochemical Assessment of Air Pollution Tolerance Index of Selected Plant Species at Ikpoba Okha Gas Flaring Site, Edo State, Nigeria
2021
Akande, Anthony | Dada, Esther | Olusola, Johnson | Adeyemi, Moyosola
The Air Pollution Tolerance index (APTI) of six plants located within Ikpoba Okha gas flaring site in Oredo Local Government Area of Edo State, Nigeria during wet and dry seasons were assessed. Plant samples for this research work were randomly collected from the vicinity of the flaring site. Six (6) sample of each plant was used for laboratory analysis. The plant parameters assessed include relative water content (RWC), the ascorbic acid content (AAC), total leaf chlorophyll (TLC) and pH extract of the leaves and were used to compute the Air pollution tolerance indices (APTI). Based on the analyzed result, the RWC in Drypetes leonensis, Ficus exasperata Vahl, Chromolaena odorata (Linn) and Gmelina arborea Roxb. ex Smith species in dry season were higher than those in wet season. Icacina tricantha showed a relatively high level of acidity when compared to others. A. boonei De Wild has the highest ascorbic acid content in the leaves in both seasons. The highest level of chlorophyll contents was recorded in the dry season with Drypetes leonensis having the highest, followed by Icacina trichantha. There was no statistically significant difference in pH and total chlorophyll contents between samples collected in wet and dry season; however, there were significant difference observed in ascorbic acid and RWC in both seasons. APTI in wet and dry season showed a statistically significant difference. This study recommends planting of tolerant species that can acts as bio-indicators especially in gas flaring stations in Nigeria.
Afficher plus [+] Moins [-]Structural and biological trait responses of diatom assemblages to organic chemicals in outdoor flow-through mesocosms
2014
Bayona, Yannick | Roucaute, Marc | Cailleaud, K. | Lagadic, Laurent | Basseres, A. | Caquet, Thierry | Écologie et santé des écosystèmes (ESE) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Service environnement ; Pôle d'Etude et de Recherche de Lacq [Total] (PERL) | Serv ice environnement ; Pôle d'Etude et de Recherche de Lacq [Total] (PERL) | Service environnement ; TOTAL Pôle d'Etude et de Recherche de Lacq | Total S.A.
The sensitivity of diatom taxonomy and trait-based endpoints to chemicals has been poorly used so far in Environmental Risk Assessment. In this study, diatom assemblages in outdoor flow-through mesocosms were exposed to thiram (35 and 170 mu g/L), and a hydrocarbon emulsion (HE; 0.01, 0.4, 2 and 20 mg/L). The effects of exposure were assessed for 12 weeks, including 9 weeks post-treatment, using taxonomic structure and diversity, bioindication indices, biological traits, functional diversity indices, indicator classes and ecological guilds. For both chemicals, diversity increased after the treatment period, and responses of ecological traits were roughly identical with an abundance increase of motile taxa tolerant to organic pollution and decrease of low profile taxa. Bioindication indices were not affected. Traits provided a complementary approach to biomass measurements and taxonomic descriptors, leading to a more comprehensive overview of ecological changes due to organic chemicals, including short- and long-term effects on biofilm structure and functioning. (C) 2014 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Occurrence and indicators of pharmaceuticals in Chinese streams: A nationwide study
2018
Yao, Bo | Yan, Shuwen | Lian, Lushi | Yang, Xin | Wan, Chunli | Dong, Hengtao | Song, Weihua
Pharmaceutically active compounds (PhACs) are excreted by humans and animals and released into the aquatic environment through wastewater, which can have potential negative impacts on ecological systems. To conduct a nationwide investigation of the occurrence of PhACs in water resources in China, an analytical procedure based on solid-phase extraction (SPE) and LC-MS/MS was used to measure 45 PhACs in surface water samples from a network of 29 rivers across 31 provinces in China in 2014 and 2015. PhACs were prevalent in all sampled streams. The concentrations of commonly detected PhACs were comparable to those detected in other countries. High total concentrations (mean > 1 μg L−1) of all tested PhACs were primarily detected in areas under extreme water stress, specifically northern and eastern coastal areas. Source apportionment based on the profiles of the target compounds found that 54% of the PhACs in China originated from freshly discharged untreated sewage. Metformin (MET) and its biodegradation product, guanylurea (GUL), were used as a pair of indicators to predict PhAC contamination levels and differentiate between biotreated and unbiotreated wastewater. High MET/GUL can be used to indicate untreated wastewater, whereas low MET/GUL values are a strong indicator of treated wastewater. Furthermore, wastewater biotreatment ratios were calculated. We estimated that the biotreatment ratios of most of the provinces in China were less than 50%. We conclude that more attention should be paid to untreated sewage water, especially water in rural areas rather than the existing concentration on urban sewage treatment-oriented management.
Afficher plus [+] Moins [-]Bibliometric study of the toxicology of nanoescale zero valent iron used in soil remediation
2019
Vanzetto, Guilherme Victor | Thomé, Antonio
The application of nanoscale zero-valent iron is one of the most widely used remediation technologies; however, the potential environmental risks of this technology are largely unknown. In order to broaden the knowledge on this subject, the present work consists of a bibliometric study of all of publications related to the toxicity of zero-valent iron nanoparticles used in soil remediation available from the Scopus (Elsevier) and Web of Science (Thompson Reuters) databases. This study presents a temporal distribution of the publications, the most cited articles, the authors who have made the greatest contribution to the theme, and the institutions, countries, and scientific journals that have published the most on this subject. The use of bibliometrics has allowed for the visualization of a panorama of the publications, providing an appropriate analysis to guide new research towards an effective contribution to science by filling the existing gaps. In particular, the lack of studies in several countries reveals a promising area for the development of further research on this topic.
Afficher plus [+] Moins [-]Evaluation of polar organic micropollutants as indicators for wastewater-related coastal water quality impairment
2016
Nödler, Karsten | Tsakiri, Maria | Aloupi, Maria | Gatidou, Georgia | Stasinakis, Athanasios S. | Licha, Tobias
Results from coastal water pollution monitoring (Lesvos Island, Greece) are presented. In total, 53 samples were analyzed for 58 polar organic micropollutants such as selected herbicides, biocides, corrosion inhibitors, stimulants, artificial sweeteners, and pharmaceuticals. Main focus is the application of a proposed wastewater indicator quartet (acesulfame, caffeine, valsartan, and valsartan acid) to detect point sources and contamination hot-spots with untreated and treated wastewater. The derived conclusions are compared with the state of knowledge regarding local land use and infrastructure. The artificial sweetener acesulfame and the stimulant caffeine were used as indicators for treated and untreated wastewater, respectively. In case of a contamination with untreated wastewater the concentration ratio of the antihypertensive valsartan and its transformation product valsartan acid was used to further refine the estimation of the residence time of the contamination. The median/maximum concentrations of acesulfame and caffeine were 5.3/178 ng L⁻¹ and 6.1/522 ng L⁻¹, respectively. Their detection frequency was 100%. Highest concentrations were detected within the urban area of the capital of the island (Mytilene). The indicator quartet in the gulfs of Gera and Kalloni (two semi-enclosed embayments on the island) demonstrated different concentration patterns. A comparatively higher proportion of untreated wastewater was detected in the gulf of Gera, which is in agreement with data on the wastewater infrastructure. The indicator quality of the micropollutants to detect wastewater was compared with electrical conductivity (EC) data. Due to their anthropogenic nature and low detection limits, the micropollutants are superior to EC regarding both sensitivity and selectivity. The concentrations of atrazine, diuron, and isoproturon did not exceed the annual average of their environmental quality standards (EQS) defined by the European Commission. At two sampling locations irgarol 1051 exceeded its annual average EQS value but not the maximum allowable concentration of 16 ng L⁻¹.
Afficher plus [+] Moins [-]The french approach to managing water resources in the mediterranean and the new European Water Framework Directive
2003
Henocque, Yves | Andral, Bruno
The main content of the new European Water Framework Directive is presented. Within its river basin management approach, a special mention of coastal waters status is made. Among the issues at stake are the setting up of river basin management plans, including coastal waters, and water quality assessment system leading to an harmonized definition of quality objectives and their appropriate indicators. The Rhone-Mediterranean-Corsica Water Master Plan, launched in 1996, is considered to be well fitted to this river basin approach and the necessary tools which go with it. It shows up how a river quality assessment system (SEQ) can be adapted to the coastal waters and how it can progressively lead to an efficient set of publishable environmental and performance indicators. Since planning and implementation are devolved to the lowest appropriate level, a close look is then been given at how such a system can work at the local level through different selected case studies on the French Mediterranean coast. In conclusion, some guidelines are drawn up for future initiatives towards integrated coastal area and river basin management.
Afficher plus [+] Moins [-]Benthic infaunal assemblages adjacent to an ocean outfall in Australian marine waters: Impact assessment and identification of indicator taxa
2022
Andrew-Priestley, Megan | Newton, Katie | Platell, Margaret E. | Le Strange, Lisa | Houridis, Harry | Stat, Michael | Yu, Richard Man Kit | Evans, Craig | Rogers, Zoe | Pallot, Jason | Van Den Broek, Jaman | MacFarlane, Geoff R.
An impact assessment of oceanic effluent releases from Belmont wastewater treatment works (WWTW) in Newcastle, Australia, was undertaken. Benthic infaunal assemblages in sandy sediments of ~25 m water depth were examined, at sites adjacent to the release point, and at increasing distances up to 2 km in both a NE and SW direction over five consecutive years (2016–2020). Localised impacts were evident for infaunal assemblages, with sites within 20 m of the outfall (“Impact” site types) exhibiting lower taxa richness and Shannon diversity, higher abundances of polychaetes and/or nematodes, higher polychaete ratios, and shifts in assemblage composition in comparison to sites at greater distances during some years. Taxa with increased localised abundances at the outfall were identified as indicators for monitoring impacts, including deposit-feeding polychaetes (Families Polygordiidae, Paraonidae and Dorvilleidae) and Phylum Nematoda. Future infaunal monitoring could include molecular tools and paired sediment analyses.
Afficher plus [+] Moins [-]Exploring the relation between plastic ingestion in species and its presence in seafloor bottoms
2020
Alomar, Carme | Deudero, Salud | Compa, Montserrat | Guijarro, Beatriz
In order to have a wider understanding of the impacts of plastics on marine ecosystems, studies should approach different environmental compartments, such as seafloor and biota, at the same time. The aim of this research is to study the relation between microplastic ingestion in species and the amount of seafloor plastics caught in the same bottom trawls hauls of the western Mediterranean Sea to describe a potential overlap between these two indicators of plastic pollution. According to results, 15% of the sampled individuals ingested microplastics with a mean value of 0.30 ± 0.40 microplastics/individuals. Regarding seafloor plastics, these were present in 58% of the hauls with a mean value of 1.31 ± 0.09 kg/km². The highest overlap between ingestion of microplastic in species and seafloor plastics was observed in the bay of Palma, the most urbanized area, but also in areas close to Marine Protected Areas (MPAs).
Afficher plus [+] Moins [-]Individual and population indicators of Zostera japonica respond quickly to experimental addition of sediment-nutrient and organic matter
2017
Han, Qiuying | Soissons, Laura M. | Liu, Dongyan | van Katwijk, Marieke M. | Bouma, Tjeerd J.
A manipulative field experiment was designed to investigate the effects of sediment-nutrients and sediment-organic matters on seagrasses, Zostera japonica, using individual and population indicators. The results showed that seagrasses quickly responded to sediment-nutrient and organic matter loading. That is, sediment-nutrients positively impacted on seagrasses by increasing N content of leaves and roots, leaf length and belowground biomass. Sediment-organic matter loading lowered N content of seagrass leaves and belowground biomass. Negative effects of organic matter loading were aggravated during nutrient loading, by decreasing N content of leaves, P content of roots, leaf width, shoot number in the middle period of the experiment, increasing C/N ratio of leaves, C/P and N/P ratio of roots and above to belowground biomass ratio of seagrasses. Consequently, Z. japonica could be considered as a fast indicator to monitor seagrass ecosystem status in the eutrophic areas and facilitate to interpreting the response of seagrasses to multiple stressors.
Afficher plus [+] Moins [-]Assessing the progress in depolluting the Mediterranean Sea
2016
Spiteri, Claudette | Roddier-Quefelec, Cécile | Giraud, Jean-Pierre | Hema, Tatiana
The depollution of the Mediterranean Sea by 2020 is the overarching goal of Horizon 2020 Initiative (H2020). The first phase (2007–2013) tackled the main land-based pollution sources; municipal waste, urban wastewater and industrial emissions. As part of the H2020 roadmap implementation, the ENPI-SEIS project focused on the first H2020 review mechanism that included a) establishing a process for regular environmental reporting in the European Neighbourhood Policy South countries, and b) generating the knowledge necessary to assess the progress in depolluting the Mediterranean Sea. This paper reviews the process in line with the “Shared Environmental Information System” principles and its three pillars (content, cooperation, infrastructure). The main outcomes of the thematic assessment, based on a set of regional H2020 indicators, are also presented. This assessment highlights the major drivers and their implications on marine protection. It also identifies areas that require further attention in the next phase of H2020 (2014–2020).
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