خيارات البحث
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Correction to: From legacy pollutants to emerging contaminants: recent inputs from the 2018 conference of EcoBIM network النص الكامل
2020
Auffret, Michel | Cachot, Jérôme | Saint-Louis, Richard
The original publication of this paper contains a mistake.
اظهر المزيد [+] اقل [-]Multifunctional metal-organic frameworks in oil spills and associated organic pollutant remediation النص الكامل
2020
Ejeromedoghene, Onome | Oderinde, Olayinka | Kang, Mengmeng | Agbedor, Solomon | Faruwa, Ajibola R. | Olukowi, Olubunmi M. | Fu, Guodong | Daramola, Michael O.
The release of toxic organic compounds into the environment in an event of oil spillage is a global menace due to the potential impacts on the ecosystem. Several approaches have been employed for oil spills clean-up, with adsorption technique proven to be more promising for the total reclamation of a polluted site. Of the several adsorbents so far reported, adsorbent-based porous materials have gained attention for the reduction/total removal of different compounds in environmental remediation applications. The superior potential of mesoporous materials based on metal–organic frameworks (MOFs) against conventional adsorbents is due to their intriguing and enhanced properties. Therefore, this review presents recent development in MOF composites; methods of preparation; and their practical applications towards remediating oil spill, organic pollutants, and toxic gases in different environmental media, as well as potential materials in the possible deployment in reclaiming the polluted Niger Delta due to unabated oil spillage and gas flaring.
اظهر المزيد [+] اقل [-]Assessment of climate change impacts on water quality parameters of Lake Burullus, Egypt النص الكامل
2020
Shalby, Ahmed | Elshemy, Mohamed | Zeidan, Bakenaz A.
Egyptian Mediterranean coast hosts five shallow lagoons which play a vital role in the national economy. Lake Burullus is the second largest one that is located in the Nile Delta and is connected to the Mediterranean by a narrow outlet. This lagoon faces various anthropogenic-induced implications that threat its ecosystem and biodiversity. The prime objective of this study is investigating the impacts of future climate change (CC) on its characteristics. A 2-D hydro-ecological modeling for the lagoon was implemented, using MIKE21FM. The proposed model was calibrated and validated against the collected water quality records, for two successive years (2011–2013), at twelve monitoring stations throughout the lagoon. The simulations were executed for various parameters, including water depth, salinity, DO, BOD, and nutrient components. Six simulations from different regional climate models (RCMs) were obtained and examined to extract the most accurate climatic projections for the lagoon coordinates. These climatic estimates cover three Representative Concentration Pathways (RCPs) scenarios according to the IPCC’s Fifth Assessment Report (AR5). A moderate sea level rise (SLR), locally projected offshore from the Nile Delta coast, was obtained. The validated model was forced with the climatic and SLR projections of 2 years representing the mid and long-term future of the twenty-first century. The model results showed that the developed model is an efficient tool to simulate the lagoon characteristics. The results of the modified model showed that CC has the potential to radically alter the physical and chemical structure of Lake Burullus. The results emphasized that the lagoon is expected to be warmer and more saline. The risk of oxygen depletion is firmly predictable with significant spatial differences of DO decreasing. A prolonged residence time is expected, accompanied by an increasing trend of phosphate and chlorophyll-a and a decreasing trend of nitrate. CC impacts on Lake Burullus should be considered in its urgently required management plan.
اظهر المزيد [+] اقل [-]Drainage water salinity and quality across nested scales in the Nile Delta of Egypt النص الكامل
2020
El-Agha, Doaa E. | Molle, François | Rap, Edwin | El Bialy, Maha | El-Hassan, Waleed Abou
Drainage water salinity and quality across nested scales in the Nile Delta of Egypt النص الكامل
2020
El-Agha, Doaa E. | Molle, François | Rap, Edwin | El Bialy, Maha | El-Hassan, Waleed Abou
Improving water management depends on understanding the functioning of irrigation and drainage systems across different environmental scales. For this purpose, this study in the Nile Delta of Egypt particularly examines the spatial and temporal variation of drainage water salinity from the system to the plot level. A better understanding of this variation across nested scales is crucial to refine the government’s drainage reuse strategy and reduce the adverse effects on agricultural productivity, lagoon ecology, and human health. The study investigates the drainage system of the Meet Yazid study area (82,740 ha) located in the upper central part of the Nile Delta. The parameters measured were electrical conductivity (EC), dissolved oxygen (DO), pH, and temperature. Results showed that salinity and quality of drainage water in the Nile Delta vary highly with space and time. The secondary drains exhibited the highest variability of salinity compared with main drains and subsurface drainage collectors because they accumulate salts from deeper soil layers and seepage of saline groundwater at the time of low flow discharge. In secondary drains, the salinity increased up to four times that of drainage water coming from the collectors. Moreover, DO values were most of the time not meeting standards for reuse in irrigation, especially at main drains that collect not only agricultural drainage but also untreated household sewage water.
اظهر المزيد [+] اقل [-]Drainage water salinity and quality across nested scales in the Nile Delta of Egypt النص الكامل
2020
El-Agha, Doaa, E | Molle, François | Rap, Edwin | El Bialy, Maha | El-Hassan, Waleed, Abou | Institut de Recherche pour le Développement (IRD [Bolivie]) | Gestion de l'Eau, Acteurs, Usages (UMR G-EAU) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-AgroParisTech-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro - Montpellier SupAgro ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | Institute for Water Education (IHE Delft) | Australian Centre for International Agricultural Research (ACIAR) - LWR/2011/045
International audience | Improving water management depends on understanding the functioning of irrigation and drainage systems across different environmental scales. For this purpose, this study in the Nile Delta of Egypt particularly examines the spatial and temporal variation of drainage water salinity from the system to the plot level. A better understanding of this variation across nested scales is crucial to refine the government's drainage reuse strategy and reduce the adverse effects on agricultural productivity, lagoon ecology, and human health. The study investigates the drainage system of the Meet Yazid study area (82,740 ha) located in the upper central part of the Nile Delta. The parameters measured were electrical conductivity (EC), dissolved oxygen (DO), pH, and temperature. Results showed that salinity and quality of drainage water in the Nile Delta vary highly with space and time. The secondary drains exhibited the highest variability of salinity compared with main drains and subsurface drainage collectors because they accumulate salts from deeper soil layers and seepage of saline groundwater at the time of low flow discharge. In secondary drains, the salinity increased up to four times that of drainage water coming from the collectors. Moreover, DO values were most of the time not meeting standards for reuse in irrigation, especially at main drains that collect not only agricultural drainage but also untreated household sewage water.
اظهر المزيد [+] اقل [-]Analysis of the PM2.5 emission inventory and source apportionment in Jilin City, Northeast of China النص الكامل
2020
Fang, Chunsheng | Wang, Liyuan | Gao, Hanbo | Wang, Ju
This study collected and compiled statistical data on atmospheric pollution in Jilin City, China during 2013–2014, using models and methods to calculate the source proportion of PM₂.₅ emitted by various sources. The statistical activity levels and emission factors of various pollution sources were found to be key parameters for obtaining the total amount of PM₂.₅ in the exhaust gas emitted from all types of pollution sources using an emissions model. In this study, relevant data were collected by the top-down method, and pollutant emission was calculated by the emission factor method to establish the PM₂.₅ pollution emission inventory of Jilin City. The source apportionment was calculated using the Chemical Mass Balance (CMB) model. Industrial process source and fixed combustion source are the largest sources of PM₂.₅ emission from all sources, respectively. Among the two calculation results, the results of pollution emission inventory are more accurate. The PM₂.₅ emission inventory in Jilin was established and countermeasures were proposed focused on the coordinated control of air pollution and the prevention and control of industrial dust pollution sources, as well as environmental management and impact assessment.
اظهر المزيد [+] اقل [-]Insight into nitrogen and phosphorus enrichment on cadmium phytoextraction of hydroponically grown Salix matsudana Koidz cuttings النص الكامل
2020
Kong, Xiangshi | Zhao, Yunxia | Tian, Kai | He, Xingbing | Jia, Yanyan | He, Zaihua | Wang, Wenwen | Xiang, Changguo | Tian, Xingjun
Cadmium (Cd) has already caused worldwide concern because of its high biotoxicity to human and plants. This study investigated how nitrogen (N) and phosphorus (P) enrichment alter the toxic morpho-physiological impacts of and accumulation of Cd in hydroponically grown Salix matsudana Koidz cuttings. Our results showed that Cd significantly depressed growth and induced a physiological response on S. matsudana cuttings, exhibiting by reduced biomass, decreased photosynthetic pigment concentrations, and increased soluble protein and peroxidase activity of shoots and roots. N and P enrichment alleviated the Cd toxic effects by increasing production of proline which prevented cuttings from damage by Cd-induced ROS, displaying with decreased malondialdehyde concentration, and stimulated overall Cd accumulation. Enrichment of N and P significantly decreased the upward Cd transfer, combing with enhanced root uptake (stimulated root activity) and retranslocation from stem, resulted in extensive Cd sequestration in S. matsudana roots. In both root and xylem, concentration of Cd is positively correlated with N and P. The improved phytoextraction potential by N and P enrichment was mainly via elevating Cd concentration in roots, probably by increased production of phytochelatins (e.g., proline) which form Cd chelates and help preventing damage from Cd-induced ROS. This study provides support for the application of S. matsudana in Cd phytoextraction even in eutrophic aquatic environments.
اظهر المزيد [+] اقل [-]Exogenous abscisic acid (ABA) promotes cadmium (Cd) accumulation in Sedum alfredii Hance by regulating the expression of Cd stress response genes النص الكامل
2020
Lu, Qinyu | Chen, Shimiao | Li, Yanyan | Zheng, Fuhai | He, Bing | Gu, Minghua
Sedum alfredii Hance is a zinc (Zn) and cadmium (Cd) hyperaccumulator plant. However, the regulatory role of plant hormones in the Zn or Cd uptake and accumulation of S. alfredii remains unclear. In this work, the growth, Cd accumulation, abscisic acid (ABA) synthesis and catabolism, malonaldehyde (MDA) content, and transcriptional level of some Cd stress response genes under ABA and Cd co-treatment were investigated to reveal the impact of ABA on Cd resistance and Cd accumulation of S. alfredii. The results show that 0.2 mg/L ABA and 100 μmol/L Cd co-treatment enhanced Cd accumulation and growth in S. alfredii, whereas lower or higher ABA concentrations weaken or even reverse this effect, which was positively correlated with endogenous ABA content. The increase in endogenous ABA content might be the results of the increasing ABA synthetase activities and decreasing ABA lytic enzyme, which was induced by the application of 0.2 mg/L ABA under 100 μmol/L Cd treatment. Principal component analysis (PCA) indicated that ABA impacted the expression pattern of Cd stress response genes, which coincided with the Cd accumulation pattern in the shoots of S. alfredii. Cross-over analysis of partial least squares-discriminant analysis (PLS-DA) and correlation analysis indicated that HsfA4c, HMA4 expression in roots, and HMA2, HMA3, CAD, NAS expression in shoots were correlated with endogenous ABA, which suggests that endogenous ABA improves Cd resistance of seedlings, switches the root-to-shoot transporter from HMA2 to HMA4, and transports more Cd into apoplasts to promote Cd accumulation in the shoots of S. alfredii. Taken together, ABA plays an essential role not only in Cd resistance but also in Cd transport from root to shoot in S. alfredii under Cd stress.
اظهر المزيد [+] اقل [-]Phytoremediation of cadmium-contaminated wetland soil with Typha latifolia L. and the underlying mechanisms involved in the heavy-metal uptake and removal النص الكامل
2020
Yang, Yan | Shen, Qianyong
The effects of Typha latifolia L. on the remediation of cadmium (Cd) in wetland soil were studied using greenhouse pot culture, with soil Cd concentrations of 0, 1, and 30 mg/kg. The T. latifolia showed excellent tolerance to the low and high concentrations of Cd in soil. A higher bioaccumulation of Cd was observed in roots, with bioconcentration factor values of 51.6 and 9.30 at 1 and 30 mg/kg of Cd stress, respectively; Cd concentration in T. latifolia was 77.0 and 410.7 mg/kg, and Cd content was 0.11 and 0.22 mg/plant at the end of the test period. The soil enzyme activities (urease, alkaline phosphatase, and dehydrogenase) exposed to 0, 1, and 30 mg/kg Cd were measured after 0-, 30-, 60-, and 90-day cultivation period and showed an increasing trend with exposure time. Metabolite changes were analyzed using liquid chromatography-mass spectrometry, combined with principal component analysis and orthogonal partial least squares discrimination analysis. Among 102 metabolites, 21 compounds were found and identified, in response to treatment of T. latifolia with different Cd concentrations. The results showed that T. latifolia had a good remedial effect on Cd-contaminated soil. The metabolites of T. latifolia changed with different Cd concentration exposures, as a result of metabolic response of plants to Cd-contaminated soils. Analysis of metabolites could better reveal the pollution remediation mechanism involved in different Cd uptake and accumulate properties.
اظهر المزيد [+] اقل [-]How do FDI and technical innovation affect environmental quality? Evidence from China النص الكامل
2020
Hao, Yu | Wu, Yerui | Wu, Haitao | Ren, Siyu
Foreign direct investment (FDI) is an important driving force for economic growth and technological innovation, but it also brings environmental pollution problems along with economic development. From the perspective of technological innovation, the impact of FDI on China’s environmental pollution deserves further study. With the spatial econometric tools employed to account for the potential spatial dependence of environmental pollution, this study uses the panel data of 30 province-level units in China from 1998 to 2016 to investigate the impact of FDI and technological innovation on environmental pollution. The results show that increased FDI can reduce environmental pollution, confirming the existence of the “pollution halo hypothesis”; technological innovation can reduce the emissions of sulfur dioxide and smoke dust but increase the chemical oxygen demand. Therefore, vigorous introduction of foreign capital is good for sustainable development for government, but it is also necessary to pay attention to screening and identifying environment-friendly enterprises with advanced production technology and management experience and to reject high-pollution and high-energy-consuming enterprises eliminated by developed countries.
اظهر المزيد [+] اقل [-]Plastic floating debris along a summer-winter estuarine environmental gradient in a coastal lagoon: how does plastic debris arrive in a conservation unit? النص الكامل
2020
Lorenzi, Luciano | Reginato, Bruna Conte | Mayer, Devon Gebauer | Dantas, David Valença
Improper management of plastic waste is an important contributor to the pollution in water bodies. However, how floating plastic debris is transported to coastal lagoons and marine conservation units is still poorly understood. This work determined the level of contamination due to floating plastic debris in Acaraí Lagoon by establishing density distribution patterns along the lagoon ecocline in the winter and summer. Four areas were chosen that followed the estuarine gradient of the lagoon (external, lower, middle, and upper), and in each area, three samples of were collected by trawling with a plankton net. The plastic debris was classified into paint fragments, hard solids, plastic filaments, and soft plastics, and the plastic debris density and surface area were determined in each sampling area. The concentrations of the plastics in the downstream and upstream areas resulted from the high density of debris that occurred during the winter due to the absence of rain and the entry of coastal waters into the lagoon. The reduced abundance and surface area of the plastics in the summer were related to the substantial output of water from the interior of the lagoon to the mouth of the lagoon due to high rainfall during this season. The absence of plastic waste management actions and developed areas at the mouth of the lagoon that were associated with the spatial and temporal fluctuations in the environmental variables favored the occurrence and high abundance of plastic debris in the water column, contaminating the entire system of Acaraí State Park.
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