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Combined effects of goethite nanoparticles with metallic contaminants and an organophosphorus pesticide on Eisenia andrei Full text
2020
Cáceres-Wenzel, Marcela I. | Fuchs, Julio S. | Bernassani, Florencia N. | Cochón, Adriana C.
The effects of mixtures of nanoparticles (NPs) and other chemicals have been poorly studied in terrestrial invertebrates. In this study, we investigated the effects of binary mixtures of goethite (α-FeOOH) NPs and metallic (Cd and Pb) or organic (chlorpyrifos, CPF) contaminants in Eisenia andrei earthworms. We used the filter paper contact test to evaluate (i) the uptake of NPs in organisms exposed to the mixtures of NPs+Metals and NPs+CPF and (ii) the potential effects of the mixture of NPs+CPF on the CPF-induced inhibition of the biomarker enzymes acetylcholinesterase (AChE) and carboxylesterases (CES). We used the artificial soil test to deepen the study on joint effects of NPs+CPF. All compounds were applied separately and in binary mixtures. In the single exposure treatment, Fe levels decreased significantly in organisms exposed to NPs on filter paper, suggesting systemic effects aimed at eliminating Fe incorporated through NPs. Conversely, earthworms exposed to binary mixtures showed Fe levels similar (NPs+Metals) to or higher (NPs+CPF) than controls. The earthworms single exposed to NPs presented no changes in AChE and CES activities. In the artificial soil test, the only treatment that showed AChE inhibition after 72 h was single CPF exposure, while no significant changes were observed in CES activity. However, after 7-day exposure in artificial soil or 72-h exposure on filter paper, the mixture of NPs+CPF induced a similar degree of AChE and CES inhibition as single CPF exposure. All these suggested that NPs did not produce neurotoxic effects, and that the inhibition of the enzymes’ activities in all cases was due to the presence of the pesticide. On the other hand, the differences in the pattern of Fe accumulation in the earthworms indicate that the presence of other contaminants in the exposure media can modify the uptake and/or the excretion of Fe and evidence the interactions that may be found in binary mixtures of metal oxide NPs and other pre-existing contaminants in the soil ecosystem.
Show more [+] Less [-]Differences of the microbial community structures and predicted metabolic potentials in the lake, river, and wetland sediments in Dongping Lake Basin Full text
2020
Fang, Jiaohui | Yang, Ruirui | Cao, Qingqing | Dong, Junyu | Li, Changchao | Quan, Quan | Huang, Miansong | Liu, Jian
In freshwater ecosystems, wetlands are generally distinguished from deep-water ecosystems by 2-m water level as boundary. However, the difference of sediment microbial communities between wetlands and deep-water ecosystems is still unclear. We combined 16S rRNA gene sequencing and community metabolic prediction to compare sediment microbial communities and predicted metabolic genes of wetlands (natural and constructed wetlands) and deep-water ecosystems (river and lake) along with environmental factors in summer and autumn in Dongping Lake Basin. Results showed that the deep-water ecosystems had significantly higher community richness than the wetlands in autumn in the freshwater basin, which was mostly related to the pH of sediments. However, no significant difference in community richness was found in summer. Besides, the composition of both predicted metabolic genes and microbial communities was significantly affected by dissolved organic carbon (DOC) and dissolved oxygen (DO). The wetlands exhibited high predicted gene abundances related to xenobiotic biodegradation possibly due to the high DOC or DO level. Compared with the wetlands, most of the deep-water ecosystems exhibited high predicted gene abundances related to element (carbon, nitrogen, and sulfur) metabolism possibly due to the low DOC and DO levels in the freshwater basin. This study can expand the knowledge of ecological function distribution and detoxification mechanism of microbial communities in freshwater ecosystems.
Show more [+] Less [-]Evaluation of urban comprehensive carrying capacity: case study of the Beijing–Tianjin–Hebei urban agglomeration, China Full text
2020
Zhao, Lingling | Li, Jiaying | Shao, Qinglong
An evaluation indexing system based on the theory of coordination was constructed to estimate the urban carrying capacity (UCC) of the Beijing–Tianjin–Hebei (BTH) region with four subsystems: social, economic, environmental, and transportation. This indexing system revealed the interactions between “supply” and “demand.” The improved entropy method was adopted to calculate the weight of 17 indicators and evaluate the comprehensive UCC of 13 cities in the BTH region using data covering the period 1990–2018. The results showed that two cities, Tangshan (UCC of − 0.0021) and Handan (UCC of − 0.0009), were “overloaded” in 2018, while the other 11 cities were “loadable.” The social and transportation subsystems played the most crucial roles in the evaluation. Based on the results, Baoding achieved the highest UCC, while that of Tangshan was the lowest. The results could play a significant role in decision-making relating to the sustainable development of the BTH region. Three policy implications are proposed based on these findings: (i) the efficiency of resource utilization and scientific allocation should be enhanced and industrial optimization and upgrading should be promoted, (ii) the coordinated development of urbanization and environment in the region should be improved, and (iii) the integration of traffic decongestion measures should be faster, and industrial docking systems should be enhanced.
Show more [+] Less [-]Pig barns ammonia and greenhouse gas emission mitigation by slurry aeration and acid scrubber Full text
2020
Mostafa, Ehab | Selders, Anne | Gates, Richard S. | Buescher, Wolfgang
Livestock production is associated with several gaseous pollutant emissions to the environment. These emissions can degrade local and regional air quality, contribute to surface water eutrophication and acid rain, and contribute to the greenhouse gas footprint of the production sector. Modern production systems must balance animal welfare and environmental pollution potential with economic reality, which is a great challenge to maintain as global demand for animal protein increases. Accordingly, gaseous emission technologies were the main target for this research, in which mitigating gas emissions of ammonia, nitrous oxide, and methane from pig production facilities via slurry aeration system was tested. Five treatments with different airflow rates in the test room were examined continuously over a period of 6 weeks and the results were compared with the control room. Test results indicate that the highest mitigation potentials were 12, 57.6, and 10.4% for nitrous oxide, methane, and ammonia, respectively. Subsequently directing exhaust air into a sulfuric acid air scrubber at 3.0 pH further reduced total ammonia emissions by 80 to 87%.
Show more [+] Less [-]Groundwater pollution source apportionment using principal component analysis in a multiple land-use area in southwestern China Full text
2020
Li, Qiling | Zhang, Han | Guo, Shanshan | Fu, Kang | Liao, Lei | Xu, Yi | Cheng, Siqian
Identification of different pollution sources in groundwater is challenging, especially in areas with diverse land uses and receiving multiple inputs. In this study, principal component analysis (PCA) was combined with geographic information system (GIS) to explore the spatial and temporal variation of groundwater quality and to identify the sources of pollution and main factors governing the quality of groundwater in a multiple land-use area in southwestern China. Groundwater samples collected from 26 wells in 2012 and 38 wells in 2018 were analyzed for 13 water quality parameters. The PCA results showed that the hydro-geochemical process was the predominant factor determining groundwater quality, followed by agricultural activities, domestic sewage discharges, and industrial sewage discharges. Agriculture expansion from 2012 to 2018 resulted in increased apportionment of agricultural pollution. In contrast, economic restructure and infrastructure improvement reduced the contributions of domestic sewage and industrial pollution. Anthropogenic activities were found the major causes of elevated nitrogen concentrations (NO₃⁻, NO₂⁻, NH₄⁺) in groundwater, highlighting the necessity of controlling N sources through effective fertilizer managements in agricultural areas and reducing sewage discharges in urban areas. The applications of GIS and PCA successfully identified the sources of pollutants and major factors driving the variations of groundwater quality in tested years.
Show more [+] Less [-]Climate change impacts and adaptations for fine, coarse, and hybrid rice using CERES-Rice Full text
2020
Nasir, Irfan Rasool | Rasul, Fahd | Ashfaq, Ahmad | Asghar, Hafiz Naeem | Hoogenboom, Gerrit
Climate change has become a threatening issue for major field crops of Pakistan, especially rice. A 2 years’ (2014 and 2015) field trial was conducted on fine, coarse, and hybrid rice at Research Area, Department of Agronomy, University of Agriculture, Faisalabad following the split-plot design. Data of growth, yield, and yield components were collected to calibrate and evaluate the CERES-Rice model under Decision Support System for Agro-technology Transfer (DSSAT). Two cultivars of each type of fine, coarse, and hybrid rice were transplanted with interval of fortnight from May to September during 2014 and 2015. The model was calibrated with non-stressed sowing data during the year 2014 and evaluated with the data of 2015. Climate change scenarios were generated for mid-century (2040–2069) under representative concentration pathway (RCP8.5) using different general circulation models (GCMs) (baseline, cool dry, hot dry, cool wet, hot wet, and middle) were using different General Circulation Models (GCMs). CERES-Rice calibration and evaluation results were quite good to simulate impacts of climate change and to formulate adaptations during 2040–2069 (mid-century). Simulations of all GCMs showed an average increase of 3 °C in average temperature as compared to baseline (1980–2010). Likewise, there would be an average increase of 107.6 mm in rainfall than baseline. The future rise in temperature will reduced the paddy yield by 10.33% in fine, 18–54% in coarse and 24–64% in hybrid rice for mid-century under RCP8.5. To nullified deleterious effects of climate change, some agronomic and genetics adaptation strategies were evaluated with CERES-rice during mid-century. Paddy yield of fine rice was increased by 15% in cool dry and 5% in hot dry GCM. Paddy yield of coarse rice was improved by 15% and 9% under cool dry and hot dry climatic conditions, respectively, with adaptations. For hybrid rice, paddy yield was enhanced by 15% and 0.3% with cool wet and hot dry climatic conditions, respectively. Hot dry climatic conditions were the most threatening for rice crop in rice producing areas of Punjab, Pakistan.
Show more [+] Less [-]In situ stabilization of heavy metals in a tailing pond with a new method for the addition of mineral stabilizers—high-pressure rotary jet technology Full text
2020
Ma, Bo | Wang, Zhe | Yuan, Xin | Cen, Kuang | Li, Jie | Yang, Ning | Zhu, Xiaohua
As the demand for metal minerals grows, the number of mine tailings increases dramatically worldwide. Toxic heavy metals (HMs) in tailings tend to migrate into the environment and cause serious damage to the surroundings. Possible eco-friendly solutions for the in situ stabilization of HMs in tailing ponds are required to reduce their mobility. Leaching tests were performed with attapulgite, zeolite, and bentonite to determine which stabilizer is more efficient. As a result, attapulgite has more significant effect with certain dose on metal mine tailings than zeolite or bentonite, especially in a strongly acidic environment. In addition, an in situ stabilization experiment was performed by adding a stabilizer to a lead-zinc mine tailing pond with high-pressure rotary jet technology. The field experiment indicated that the concentrations of HMs in the leachate substantially decreased (30.5% for Cr, 43.1% for Cu, 87.8% for Zn, 82.9% for Cd, and 42.4% for Pb) after the HMs were stabilized by high-pressure rotary jet technology. A set of parameters for the rotary jet process was obtained when the in situ stabilization experiment was carried out.
Show more [+] Less [-]Factor decomposition and decoupling analysis of air pollutant emissions in China’s iron and steel industry Full text
2020
Wang, Xiaoling | Gao, Xuena | Shao, Qinglong | Wei, Yawen
With its major influences on economic growth, energy consumption, and environmental quality, the iron and steel (IS) industry plays an important role in achieving green growth of the national economy. It is also the main air pollutant emitter compared with other industries. Therefore, this study first investigates the influencing factors of air pollutant emissions of the IS industry from dimensions of environmental regulation effect, pollutant generation intensity effect, energy structure effect, technological progress effect, and scale effect using the logarithmic mean Divisia index (LMDI) method. Additionally, decoupling effort values are further calculated to obtain the efforts made in different historical stages to achieve decoupling between the growth of the IS industry and its pollutant emissions. Three main conclusions can be summarized based on the empirical analysis of China’s IS industry from 2005 to 2015. First, environmental regulation plays a decisive role in mitigating air pollution in the IS industry. Second, environmental regulation and technological progress both exert inhibitory effects on air pollutant emissions, whereas the intensity effect of pollutant generation and scale effect promote emissions to some extent. The role of energy structural effect is unstable, yet the cumulative effect analysis shows that the effect exerts greater impacts on emission reduction during the recent period. Third, decoupling efforts of the industry gradually changed from weak to strong. In specific, the effects of environmental regulation and technological progress both promote decoupling. Conclusions are made, and suggestions are highlighted based on the research findings.
Show more [+] Less [-]Synthesis of zeolite NaY supported Mn-doped ZnS quantum dots and investigation of their photodegradation ability towards organic dyes Full text
2020
Ahmadi, Zahra | Ramezani, Hamed | Azizi, Seyed Naser | Chaichi, Mohammad Javad
In this work, Mn-doped ZnS quantum dots capped by L-cysteine (Mn@ZnS/L-cyst) and polyethylene glycol (Mn@ZnS/PEG) and also Mn-doped ZnS on zeolite NaY (Mn@ZnS/Y) were synthesized. These compounds were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and ultraviolet-visible and fluorescence spectroscopy. Then, the photodegradation ability of these three photocatalysts was investigated for degradation of 4′,5′-dibromofluorescein dye under ultraviolet irradiation. In the next stage, the different effective parameters on degradation performance, such as pH, catalyst dosage, and initial dye concentration, were studied. Results demonstrated that the optimum initial concentration was 40 mg L⁻¹ for all three catalysts. The optimum catalyst dosage for both Mn-doped ZnS quantum dots capped by L-cysteine and Mn-doped ZnS on zeolite NaY was 0.017 g L⁻¹ and for Mn-doped ZnS quantum dots capped by polyethylene glycol was 0.033 g L⁻¹. The degradation efficiency of 97% for all three photocatalysts was achieved; therefore, by considering the higher production yield of quantum dots onto zeolite and also the more convenient recovery of the Mn-doped ZnS on zeolite NaY from the solution, it seems synthesis of quantum dots onto the zeolites is a reasonable strategy.
Show more [+] Less [-]Establishment of resveratrol and its derivatives as neuroprotectant against monocrotophos-induced alteration in NIPBL and POU4F1 protein through molecular docking studies Full text
2020
Yadav, Ruchi | Srivastava, Prachi
Monocrotophos (MCP) is a broad spectrum organophosphorus insecticide, which is widely used as foliar spray to the different important crops. MCP may reach the soil and the aquatic environment directly or indirectly during and after the application, which leads to the different environmental issues. MCP is found to be associated with neurotoxicity and its toxic effects have been monitored during different stages of neuronal development. Identification of gene expression in MCP-induced neurotoxicity during neuronal developmental stage is a major area of genomic research interest. In accordance with this identification, screening of potential neuroprotective, natural resources are also required as a preventive aspects by targeting the impaired genes. In this current course of work, microarray experiment has been used to identify genes that were expressed in monocrotophos (MCP)-induced mesenchymal stem cells (MSC) and also the neuroprotectant activity of RV on MCP-exposed MSCs. Microarray experiment data have been deposited in NCBI’s Gene Expression Omnibus database and are accessible through GEO Series accession number GSE121261. In this paper, we have discussed two important genes NIPBL (nipped-B-like protein) and POU4F1 (POU domain, class 4, transcription factor 1). These genes were found to be significantly expressed in MCP-exposed MSC and show minimum expression in presence of RV. Homology modelling and docking study was done to identify the interaction and binding affinity of resveratrol and its derivatives with NIPBL and POU4F1 protein. Docking analysis shows that RV and its derivatives have strong interaction with NIPBL and POU4F1 protein hence proves the significance of resveratrol as potential neuroprotectant. This paper highlights the hazardous impact of MCP on neuronal development disorders and repairing potentiality of RV and its derivatives on altered genes involved in neuronal diseases. Graphical Abstract
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