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Coordinated development of economic growth and ecological efficiency in Jiangsu, China 全文
2020
Wang, Shijin | Hua, Guihong | Yang, Lizhu
In order to realize sustainable development, ecological efficiency is particularly important and deserving of further study and discussion in China. Thus, the study proposed a comprehensive index for ecological efficiency in Jiangsu and evaluated the ecological efficiency of 13 cities in the year of 2007, 2012, and 2017 by using entropy-weighting TOPSIS method. Based on coupling model, the study discussed the interaction between economic growth and ecological efficiency in Jiangsu. The results indicated that the ecological efficiency of Jiangsu in these three years differed considerably. Ecological efficiency is the highest in central Jiangsu, whereas ecological efficiency in the northern and southern parts of Jiangsu is relatively low from the perspective of horizontal space. In terms of coupling, Wuxi and Suzhou were the stablest in southern Jiangsu. Economic growth in the central Jiangsu fluctuated, Suqian lagged. Furthermore, based on the findings, the industrial structure should be adjusted to improve ecological efficiency. In addition, the use of innovation and rational foreign direct investment and other measures should be promoted. These proposals aim at improving ecological efficiency and achieving overall sustainable development in Jiangsu, China.
显示更多 [+] 显示较少 [-]2,4-Dichlorophenoxyacetic acid herbicide effects on zebrafish larvae: development, neurotransmission and behavior as sensitive endpoints 全文
2020
Gaaied, Sonia | Oliveira, Miguel | Domingues, Inês | Banni, Mohamed
Assessment of pesticides toxicity using zebrafish early life stages is relevant for aquatic systems safety. This study aimed to evaluate the short-term effects of 2,4-dichlorophenoxyacetic acid (2,4-D) on zebrafish (Danio rerio) embryos from 3 h post fertilization to 96 hpf. A set of 2,4-D concentrations ranging from 0.32 to 80 mg/L were tested and median lethal concentration (LC₅₀) at 96-h was calculated as 2.86 mg/L. A sub-teratogenic concentrations range from 0.02 to 0.8 mg/L was then used to assess effects at ontogenic, biochemical, and behavioral levels. The main developmental defects were tail deformities and pericardial edema at concentrations equal or above 0.32 mg/L. Cholinesterase activity (at 96 hpf) and larvae swimming behavior (at 120 hpf) were affected even at the lowest tested dose (0.02 mg/L). The behavior analysis was a sensitive endpoint, with a decrease in the swimming distance of exposed larvae during light period. The effect of 2,4-D in ChE was translated by an inhibition of the enzyme activity in all treated groups. These findings demonstrate that 2,4-D can alter the cholinergic system by affecting ChE activity which may be involved in the locomotion reduction of exposed larvae and emphasize the potential of neurotransmission and behavioral endpoints as early warning signs of herbicides contamination in aquatic ecosystems.
显示更多 [+] 显示较少 [-]Spatiotemporal variation and determinants of population’s PM2.5 exposure risk in China, 1998–2017: a case study of the Beijing-Tianjin-Hebei region 全文
2020
Jin, Ning | Li, Junming | Jin, Meijun | Zhang, Xiaoyan
PM₂.₅ pollution has emerged as a global human health risk. The best measure of its impact is a population’s PM₂.₅ exposure (PPM₂.₅E), an index that simultaneously considers PM₂.₅ concentrations and population spatial density. The spatiotemporal variation of PPM₂.₅E over the Beijing-Tianjin-Hebei (BTH) region, which is the national capital region of China, was investigated using a Bayesian space-time model, and the influence patterns of the anthropic and geographical factors were identified using the GeoDetector model and Pearson correlation analysis. The spatial pattern of PPM₂.₅E maintained a stable structure over the BTH region’s distinct terrain, which has been described as “high in the northwest, low in the southeast”. The spatial difference of PPM₂.₅E intensified annually. An overall increase of 6.192 (95% CI 6.186, 6.203) ×10³ μg/m³ ∙ persons/km² per year occurred over the BTH region from 1998 to 2017. The evolution of PPM₂.₅E in the region can be described as “high value, high increase” and “low value, low increase”, since human activities related to gross domestic product (GDP) and energy consumption (EC) were the main factors in its occurrence. GDP had the strongest explanatory power of 76% (P < 0.01), followed by EC and elevation (EL), which accounted for 61% (P < 0.01) and 40% (P < 0.01), respectively. There were four factors, proportion of secondary industry (PSI), normalized differential vegetation index (NDVI), relief amplitude (RA), and EL, associated negatively with PPM₂.₅E and four factors, GDP, EC, annual precipitation (AP), and annual average temperature (AAT), associated positively with PPM₂.₅E. Remarkably, the interaction of GDP and NDVI, which was 90%, had the greatest explanatory power for PPM₂.₅E ′ s diffusion and impact on the BTH region.
显示更多 [+] 显示较少 [-]Multivariate spatial analysis for the identification of criticalities and of the subtended causes in river ecosystems 全文
2020
Bellino, Alessandro | Alfani, Anna | De Riso, Laura | Baldantoni, Daniela
In statistics, the identification of environmental criticalities, one of the primary goals of environmental monitoring and management, translates into the detection of spatial outliers. Detected in relation to purposely defined sets of indicators, both global and local outliers are pivotal in the identification not only of the severity and spread of criticalities, but also of their nature and causes. The present research exemplifies a procedural framework to identify environmental criticalities, using two different approaches for the detection of spatial outliers in river ecosystems related to several sets of parameters (organic C, inorganic C, Ca, Co, Cr, Fe, K, Mg, Mn, N, Na, P, S, Si, V, Zn, Cl⁻, F⁻, NO₃⁻, SO₄²⁻, chlorophyll a, chlorophyll b, pheophytin a, pheophytin b, total carotenoids, pH, and electrical conductivity), including emerging contaminants. To this end, indicator sets diagnostic for specific criticalities, derived from an empirical dataset of water quality parameters, were employed, using detection techniques based on geographically weighted principal component analysis and a modified pairwise Mahalanobis distance–based algorithm. Clear and accurate criticality scenarios were derived, highlighting both the strengths and the limitations of the proposed approach, especially in relation to the classic threshold-based methods.
显示更多 [+] 显示较少 [-]Spatial and temporal variability in concentration and characteristics of aerosols at Visakhapatnam (east) and Goa (west) coasts of India 全文
2020
Yadav, K. | Sarma, V. V. S. S. | Dileep Kumar, M.
Knowledge on the variability in quantity and compositions of various size groups of aerosols is important to understand their sources and their role in biogeochemical and climate processes. Here, we studied total suspended particles (TSP), PM₁₀ and PM₂.₅ for their quantitative and water soluble compositional (F⁻, Cl⁻, SO₄²⁻, NO₃⁻, NH₄⁺, Na⁺, K⁺, Ca²⁺, and Mg²⁺) distributions, and to understand their nature and potential sources at Goa and Visakhapatnam on the west and east coasts, respectively, of India. While the mean concentrations of TSP were found to be 117 ± 44 and 85 ± 51 μg/m³ its maximal levels occurred in spring intermonsoon (SIM; 141 ± 52) and winter monsoon (WM; 155 ± 145 μg/m³) seasons at Goa and Visakhapatnam, respectively. PM₁₀ and PM₂.₅ exhibited higher ranges at Visakhapatnam than Goa. The increase in PM₂.₅ abundance from WM to SIM at Visakhapatnam seems to occur in coincidence with decrease in TSP favored by topography and ambient meteorological conditions. Locally released and seasonally transported (from land and sea) constituents contributed to the observed variability in aerosol compositions. Sulphate dominated the aerosol composition at both Goa (57–64%) and Visakhapatnam (43–55%) followed by NO₃⁻ (5–16% and 6–18%, respectively) where the former component was higher in PM₁₀ and PM₂.₅. The NO₃⁻ was more in TSP. Relations between SO₄²⁻ and NH₄⁺ suggested possible presence of NH₄HSO₄. Examination of ionic ratios and balance suggested near neutrality in PM₁₀ and PM₂.₅ while TSP was acidic at the both locations. Notable relations between Ca²⁺ and NO₃⁻, particularly in PM₁₀ at Goa, indicated their release from mining related activities.
显示更多 [+] 显示较少 [-]Understanding boosting selenium accumulation in Wheat (Triticum aestivum L.) following foliar selenium application at different stages, forms, and doses 全文
2020
Wang, Min | Ali, Fayaz | Wang, Mengke | Dinh, Quang Toan | Zhou, Fei | Bañuelos, Gary S. | Liang, Dongli
There are a lack of systematic studies comparing the effects of foliar-applied selenium (Se) with different Se sources at different growth stages in wheat. Herein, we biofortified wheat via the foliar application of selenite and selenate at different rates and different stages under field conditions. Results showed that foliar-applied selenate and selenite had no significant effect either on wheat biomass or grain yield (p < 0.05). Selenium distribution in different parts of wheat plant ranked decrease as leaf > root > grain > glume > stem with selenite treatment, and it appeared in the decline order as leaf > grain > glume > stem > root with selenate treatment. These results suggested that biofortification with selenate caused, relatively to selenite, a higher accumulation of Se in grains. Foliar application of Se of either selenate or selenite at pre-filling stage was superior in improving the Se concentration of wheat grains than application at pre-flowering stage. Meanwhile, organic Se comprised about 72–93% of total Se in wheat grains, which was reduced by 5.8% at high Se rate (100 g ha⁻¹), irrespective of the forms of Se or stages applied. The organic Se proportion in wheat grains was 9% higher with the selenate treatment than with the selenite treatment. Selenomethionine (SeMet) was the main organic species (67–86%) in wheat grains, followed by selenocysteine (SeCys₂). In summary, our results indicate that Se biofortification of wheat is most effective with 20 g ha⁻¹ selenate foliar-applied at pre-filling stage.
显示更多 [+] 显示较少 [-]Adsorption and reduction of Cr(VI) by hydroxylated multiwalled carbon nanotubes: effects of humic acid and surfactants 全文
2020
Huang, Yu | Song, Ke | Luo, Wei | Yang, Jiewen
The present study investigated the impacts of humic acid (HA) and surfactants (SDBS and CTAB), which were ubiquitously found in the aquatic environments, on the removal of Cr(VI) by the hydroxylated MWCNTs-OH. The results showed that MWCNTs-OH could remove Cr(VI) from aqueous solution via adsorption coupled with reduction, and the kinetics followed the pseudo-first-order model with the rate of 3.5 × 10⁻³ h⁻¹. In the presence of anionic SDBS, the removal percentage of Cr(VI) was greatly inhibited because the hydrophobic interaction and π-π interaction between SDBS and MWCNTs-OH surfaces not only decreased the adsorption sites for Cr(VI) but also made the surfaces more negatively charged. On the contrary, the existence of cationic CTAB could lead to the surfaces more positively charged, which consequently enhance the electrostatic attraction between Cr(VI) and the surfaces as well as the removal of Cr(VI). Noticeably, the presence of HA could promote the removal of Cr(VI), which was attributed to the reduction of Cr(VI) by the adsorbed HA. The ESR spectra indicated the existence of π-type radicals in HA structure and conduction electrons in MWCNTs-OH, and then the π-π interaction between MWCNTs-OH and adsorbed HA possibly increase the electron-donating ability of HA. Moreover, the promotive effect of HA could be enhanced with the addition of Ca²⁺. This study was helpful for us to understand the role of MWCNTs-OH in controlling the fate of Cr(VI) when HA and surfactants were present.
显示更多 [+] 显示较少 [-]Tanning process promotes abiotic humification: separation and characterization of humic acid-like polymers complex 全文
2020
Zhu, Chao | Wang, Huiqin | Ma, Hongrui | Yang, Yonglin | Li, Fan
Humic-like substances are essential components of soluble organic matter in tannery wastewater. However, the tannery process can promote the abiotic humification in wastewater. Therefore, it is of great significance to clarify the pathway and degree of abiotic humification and the properties of the as-derived humic acid-like (HAL) complex polymers in the tannery process in order to control the refractory organic compounds. In the present study, considering the catechol-Maillard system and commercial humic acid (HA) as control, the polyphenol-Maillard humification in the tannery process was simulated under the catalysis of MnO₂. Moreover, physicochemical and spectroscopic techniques were used to characterize the separated fractions of HAL further. As a result, it was found that the catechol-Maillard system with small molecule organic matter as precursor had higher humification degree. Furthermore, the ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), and excitation-emission matrix (EEM) fluorescence spectrum of humic acid-like 0 (HAL0) derived from it was different from those of humic acid-like 1 and 2 (HAL1 and HAL2) of polyphenol-Maillard system, indicating the differences of polymer structure between them. In the polyphenol-Maillard system, tannin was the skeleton of polymerization or polycondensation reaction, and the high content of N and the H/C value of HAL2 indicated that in adding to amino acids, proteins promoted the humification, forming industry-specific HAL polymers with a high degree of aliphatic nature. Therefore, it can be concluded that controlling the raw materials in the tannery process (especially tannins), in order to reduce the occurrence of abiotic humification may be the key to improve the efficiency of wastewater treatment.
显示更多 [+] 显示较少 [-]Environmental risks among rice farmers and factors influencing their risk perceptions and attitudes in Punjab, Pakistan 全文
2020
Ahmad, Dilshad | Afzal, Muhammad | Rauf, Abdur
Farming community confronted with sundry type of risks while production and environmental risks are more significant. Farms management decisions and operations are considerably influenced by farmers’ perceptions and attitude to risks. Risk management issues specific to cereals crops not properly focused in developing countries specifically to Pakistan, so this gap tried to address in this study. This research work was spotlighted to quantify farmers’ perception and attitude of diverse form of risks toward rice crop in Pakistan. The present study used cross-sectional data of 450 rice farmers categorized as low, medium, and high production base six rice districts of Punjab, Pakistan. In attempting to identify farmers attitude to risk, the study used Equally Likely Certainty Equivalent approach, as farmers’ perception were ranked in four catastrophic risk basis, rice diseases, high input prices, drought, and heavy rainfall and hail, by risk matrix. In estimating the factors influencing farmers’ attitude and perceptions to risk, the study used Probit model. Farmers believe heavy rainfall and hails, high input prices, drought, and rice disease major threats for rice crop while mostly farmer is risk-averse behavior as indicated in the results of the study. Estimates of the study signified as education, gender, size of farm, religious, age, credit, off-farm income, farmer livestock, and experience of farming significantly influences farmer risk perception and risk attitude. This research provided applied and suitable investigation for farming community, extension services, researchers, agricultural policymakers, and insurance institutions. Farmers confronting risk and their attitude need to understand by researcher and policymakers’ access them accurate information regarding sophisticated tools of risk management and risks to make sure the provision of advance extension services and agricultural finance. In formulating applied policy measures, it is prerequisite for researchers and policymakers to accurate understanding of local environmental conditions, crop-related threats, and farmers’ perceptions and attitude.
显示更多 [+] 显示较少 [-]An environmentally realistic pesticide and copper mixture impacts embryonic development and DNA integrity of the Pacific oyster, Crassostrea gigas 全文
2020
Mai Hương, | Cachot, Jérôme | Clérandeau, Christelle | Martin, Caroline | Mazzela, Nicolas | Gonzalez, Patrice | Morin, Bénédicte
An environmentally realistic pesticide and copper mixture impacts embryonic development and DNA integrity of the Pacific oyster, Crassostrea gigas 全文
2020
Mai Hương, | Cachot, Jérôme | Clérandeau, Christelle | Martin, Caroline | Mazzela, Nicolas | Gonzalez, Patrice | Morin, Bénédicte
Frequent occurrences of pesticides in the environment have raised concerns that combined exposure to these chemicals may result in enhanced toxicity through additive or synergistic interaction between compounds. Spermatozoa and embryos of the Pacific oyster, Crassostrea gigas, were exposed to different concentrations of a pesticide mixture with and without copper, mimicking the cocktail of pollutants occurring in the oyster culture area of Arcachon Bay. For the 1× exposure condition, measured concentration corresponds to a total concentration of 1.083 μg L⁻¹ for the mixture of 14 pesticides and to 6.330 μg L⁻¹ for copper (Cu). Several endpoints including larval abnormalities, DNA damage to spermatozoa and embryo and gene expression in D-larvae were investigated. Results demonstrated that pesticide mixtures in combination with or without copper induced a dose-dependent increase in embryotoxic and genotoxic effects on D-larvae from the lowest tested dose of 0.1×. Transcription of genes involved in anti-oxidative stress (cat), respiratory chain (coxI), metal detoxification (mt1 and mt2), and cell cycle arrest and apoptosis (p53) was found to be significantly downregulated while the xenobiotic biotransformation gene gst was significantly upregulated in embryos exposed to pesticide mixture with and without Cu. These findings raise the question of the possible impacts of mixtures of pesticides and metals on wild or farmed oyster populations from polluted coastal marine areas.
显示更多 [+] 显示较少 [-]An environmentally realistic pesticide and copper mixture impacts embryonic development and DNA integrity of the Pacific oyster, Crassostrea gigas 全文
2020
Mai, Huong | Cachot, Jérôme | Clérandeau, Christelle | Caroline, Martin | Mazzella, Nicolas | Gonzalez, Patrice | Morin, Bénédicte | Environnements et Paléoenvironnements OCéaniques (EPOC) ; Observatoire aquitain des sciences de l'univers (OASU) ; Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Centre National de la Recherche Scientifique (CNRS) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
[Departement_IRSTEA]Eaux [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Frequent occurrences of pesticides in the environment have raised concerns that combined exposure to these chemicals may result in enhanced toxicity through additive or synergistic interaction between compounds. Spermatozoa and embryos of the Pacific oyster, Crassostrea gigas, were exposed to different concentrations of a pesticide mixture with and without copper, mimicking the cocktail of pollutants occurring in the oyster culture area of Arcachon Bay. For the 1× exposure condition, measured concentration corresponds to a total concentration of 1.083 μg L−1 for the mixture of 14 pesticides and to 6.330 μg L−1 for copper (Cu). Several endpoints including larval abnormalities, DNA damage to spermatozoa and embryo and gene expression in D-larvae were investigated. Results demonstrated that pesticide mixtures in combination with or without copper induced a dose-dependent increase in embryotoxic and genotoxic effects on D-larvae from the lowest tested dose of 0.1×. Transcription of genes involved in anti-oxidative stress (cat), respiratory chain (coxI), metal detoxification (mt1 and mt2), and cell cycle arrest and apoptosis (p53) was found to be significantly downregulated while the xenobiotic biotransformation gene gst was significantly upregulated in embryos exposed to pesticide mixture with and without Cu. These findings raise the question of the possible impacts of mixtures of pesticides and metals on wild or farmed oyster populations from polluted coastal marine areas.
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