Κυριακή 8 Σεπτεμβρίου 2019

Effect of using public resources and training for the sustainable development of Brazilian municipalities

Abstract

The aim of this study was to analyze the effect of using public resources and training for the sustainable development of Brazilian municipalities. To reach this objective, the data from 5569 municipalities in 2017 were analyzed. The data were collected in the IBGE (Brazilian Institute of Geography and Statistics) census and analyzed using structural equation modeling with PLS (Partial Least Squares). PLS is a structural equation modeling method that enables you to work with complex models on more than one level of latent variables. The results show that municipal resources have a positive impact on sustainable development. This means that the municipalities whose permanent employees socially participate in forums and workplace environment committees, which have specific financial resources for sustainability, present better economic and social performance. Such social participation also has positive effects on environmental performance in these municipalities. The study also showed that the training of government employees is fundamental for the implementation of environmental management programs and for improving the social performance of Brazilian municipalities.

Mycoremediation: a treatment for heavy metal-polluted soil using indigenous metallotolerant fungi

Abstract

Bioleaching of heavy metals from industrial contaminated soil using metallotolerant fungi is the most efficient, cost-effective, and eco-friendly technique. In the current study, the contaminated soil samples from Hattar Industrial Estate revealed a total lead (Pb) and mercury (Hg) concentration of 170.90 mg L−1 and 26.66 mg L−1, respectively. Indigenous metallotolerant fungal strains including Aspergillus niger M1, Aspergillus fumigatus M3, Aspergillus terreus M6, and Aspergillus flavus M7 were isolated and identified by pheno- and genotyping. A. fumigatus and A. flavus of soil sample S1 showed higher efficiency for Pb removal (99.20% and 99.30%, respectively), in SDB medium. Likewise, A. niger and A. terreus of soil sample S2 showed higher efficiency for Hg removal (96% and 95.50%, respectively), in YPG medium. Furthermore, the maximum uptake efficiency for Pb removal (8.52 mg g−1) from soil sample S1 was noticed for A. fumigatus in YPG medium, while the highest uptake efficiency (4.23 mg g−1) of A. flavus M2 strain was observed with CYE medium. Similarly, the maximum uptake efficiency of 0.41 mg g−1 and 0.44 mg g−1 for Hg removal from soil sample S2 was found for A. niger and A. terreus strains, respectively, in CYE medium. Thus, in order to address the major issue of industrial waste pollution, indigenous fungal strains A. fumigatus (M1) and A. terreus (M7), isolated in this study, could be used (ex situ or in situ) to remediate soils contaminated with Pb and Hg.

Valuation methodology of laminar erosion potential using fuzzy inference systems in a Brazilian savanna

Abstract

This study presents an approach on the evaluation of potential laminar erosion in the Ribeirão Sucuri Grande watershed. It is located in the northeast of the state of Goiás, Brazil, a conservation area under strong anthropogenic pressure. A Mamdani fuzzy inference system was designed using linguistic variables, pertinence functions, and a set of rules associated to a traditional laminar erosion prediction model through the environmental conditioners slope, erodibility, and degree of soil protection. The laminar erosion prediction model associated with fuzzy logic is a qualitative evaluation of erosive potential capable of being spatialized with a greater level of detail, increasing the traditional classification by two levels. The processing of environmental and soil conditioning factors using the fuzzy logic resulted in values between 2.5 and 9.1, which places the basin at a low to very high laminar erosion potential. The results indicate areas that demand a greater attention regarding soil management; 56.89% of the area has a medium to high laminar erosion and high to very high erosion (6.99%).

Adsorptive removal of lead (Pb), copper (Cu), nickel (Ni) and mercury (Hg) ions from water using chitosan silica gel composite

Abstract

Silica gel chitosan composite was prepared to perform adsorptive experiment of different heavy metal ion solutions. The characterization of chitosan + silica gel (Ch + Sg) composite was done by FTIR and SEM–EDS to understand the presence of active sites and to have an insight on the surface morphology. The adsorption study of heavy metal ions by Ch + Sg composite gives maximum removal percent for Cu, Pb and Ni which were obtained at pH 5 and for Hg at pH 6.The trend of removal by Ch + Sg signifies that maximum removal percent was attained at 120 min. The surface of Ch + Sg is heterogeneous for the adsorption of Hg, Ni and Cu and homogeneous for Pb adsorption. The values obtained for Pb signify that its adsorption best fitted to pseudo first order with the R2 value of 0.986, whereas pseudo second order best fitted to the experimental data of Cu, Ni and Hg as R2 values which are 0.983, 0.819 and 0.957 respectively. The values of change in entropy (⊿S) obtained for Pb, Cu, Ni and Hg are − 69.33, − 118, − 63.33 and − 98.52 J/mol K respectively. Negative values of change in enthalpy, ⊿H in (kJ/mol) are in the range of − 18.2 to − 37.66 which indicates both physical and chemical adsorption involves in the process of adsorption.

Determination of pendimethalin in water, sediment, and Procambarus clarkii by high performance liquid chromatography-triple quadrupole mass spectrometry

Abstract

We established a high-performance liquid chromatography-triple quadrupole mass spectrometry method for the analysis of pendimethalin residues in water, sediments, and Procambarus clarkii (Louisiana crayfish) tissues. Water samples were concentrated on a HLB solid-phase extraction column and eluted with dichloromethane and acetone (1:1). After drying under a stream of nitrogen gas, the sample volume was adjusted to 1 mL with the mobile phase solvent methanol/water/acetic acid (8:20:0.1). Pendimethalin was extracted with ethyl acetate containing 0.1% acetic acid, after rotary evaporation to dryness at 35 °C, the residue was dissolved in mobile phase solvent, purified by a neutral alumina column and graphitized carbon black powder (0.1 g). The mass characterization was conducted in positive ion mode, and the corresponding ions were detected in multi-reaction monitoring mode. The linear equations were y = 1 × 106x + 14275, at pendimethalin levels of 0.05–20 μg L−1 and y = 691029 × − 414368 for 20–200 μg L−1. The detection limits of pendimethalin in water, sediments, and P. clarkii tissues were 1.0 × 10−4μg L−1 , 5.0 × 10−3μg kg −1 and 5.0 × 10−3 μg kg −1, respectively. The spiked recoveries ranged from 81.6 to 106.3%, and the relative standard deviations ranged from 4.58 to 13.6% (n = 6). The method provided an efficient and low-cost extraction and purification procedure that enabled a sensitive determination of pendimethalin in water as well as complex matrices.

Experimental design of switchable solvent–based liquid phase microextraction for the accurate determination of etrimfos from water and food samples at trace levels by GC-MS

Abstract

Presented in this study is a simple but efficient switchable polarity solvent microextraction strategy for etrimfos preconcentration from water and food samples for quantification by gas chromatography mass spectrometry. Repeatability of the extraction process and instrumental measurements were enhanced by using deuterated bisphenol A as internal standard. Significant parameters of the extraction method were fitted into an experimental design model to study the effects of parameters on extraction output, as well as mutual effects of combined parameters. The design model was formed with 51 experimented data obtained from the combination of sodium hydroxide volume, switchable solvent volume, and vortex period at three levels. The method was validated by applying optimum conditions attained from the model predictor. The detection limit was found to be 1.3 ng/mL and it corresponded to an enhancement factor of about 54 folds when compared to direct GC-MS measurement. Etrimfos was not detected in the water and food samples tested but the results (92–107%) obtained from spiked recovery experiments established that etrimfos when present in the selected matrices can be accurately and precisely quantified.

Economic value of regulating ecosystem services: a comprehensive at the global level review

Abstract

This study is the first meta-regression analysis of the economic value of regulating ecosystem services at the global level. Most of the regulating ecosystem services have not been properly estimated in terms of economic value and are also ignored in the everyday decision-making process. This study has reviewed 100 publications and included 275 economic value estimates. This study includes explanatory variables in the meta-analysis to account for these influences on the estimated economic value of regulating ecosystem services. This study has estimated the economic value of regulating ecosystem services at US$29.085 trillion for 2015. This study also has found that the values of climate and water regulations are the highest contributors to the total value of regulating ecosystem services. This study indicates that the results of meta-analysis might be helpful to decision-making with respect to three aspects: first, planning and management of urban green cover for sustainable cities; second, integration of the economic value of all the regulating ecosystem services; third, budget allocation for conservation and improvement of regulating ecosystem services for the present and future generations.

Potential impacts of climate change on groundwater level through hybrid soft-computing methods: a case study—Shabestar Plain, Iran

Abstract

Groundwater aquifers have always been confronted with significant challenges around the world such as climate change, over-extraction, pollution by wastewaters, and saltwater intrusion in coastal areas. Prediction of groundwater level under the effects of climate change is more important in water resource management. This study has therefore been evaluated the effects of two climate parameters (i.e., precipitation and temperature) in groundwater level for the Shabestar Plain, Iran. For this end, four models from General Circulation Models (GCM) were then used to evaluate future climate change scenarios of the Representative Concentration Pathway (i.e., RCP2.6, RCP4.5, RCP8.5). In the next phase, to reduce the spatial complexity of observation wells, clustering analysis was used. In case of groundwater level modeling, time series in the base period, Least Square Support Vector Machine (LSSVM), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Nonlinear Autoregressive Network with Exogenous inputs (NARX) were also used. To improve the prediction accuracy, time series preprocessing made by wavelet-based de-noising approach was used. Analysis of the results illustrates an increase in temperature and a decrease in precipitation for study region in the future period times. The results also reveal that hybrid techniques of the wavelet-NARX give best results in comparison with the other models. A simulation result illustrates that the groundwater level declines in RCP2.6, 4.5, and 8.5, which gives average levels of 0.61, 0.81, and 1.53 m, respectively, for the future period years (i.e., 2020–2024). These results would lead to continuous groundwater depletion. These findings emphasize the necessity of the importance of extraction policies in water resource management.

Civilian science: the potential of participatory environmental monitoring in areas affected by armed conflicts

Abstract

Legal and policy initiatives to address the environmental dimensions of armed conflicts and their impact on people, ecosystems and sustainable development are highly dependent on the availability of environmental data from conflict-affected areas. Socio-political and security conditions in these areas often impede data collection, while traditional models of post-conflict environmental assessments are limited in scope. In response, an increasing range of actors is utilising remote sensing and open source data collection to identify and estimate health and ecological risks during and after conflicts. This paper considers the role of participatory citizen science methodologies in complementing both remote monitoring and post-conflict assessments. It examines existing models and mechanisms for environmental data collection and utilisation in conflict contexts, and the extent to which the core values and principles of citizen science are transferable. We find that ‘civilian science’ is feasible and could be well-suited to conflict conditions. In addition to addressing gaps in data collection, it may also empower communities affected by environmental degradation, enhance their environmental human rights, supplement the often limited monitoring capacity of governmental agencies and facilitate cooperation and peacebuilding. The paper concludes by proposing methodological approaches for three common forms of environmental degradation associated with armed conflicts.

Spatial patterns, geochemical evolution and quality of groundwater in Delta State, Niger Delta, Nigeria: implication for groundwater management

Abstract

Delta State of the Niger Delta, Nigeria, is an oil exploration and production region that is characterized by huge revenue generation but with its attendant waste generation and oil spillage that impact the environment. The variability in the hydrochemical characteristics, hydrochemical controlling processes and quality in space has been investigated. The pH of the groundwater samples ranged from slightly acidic to slightly alkaline nature. Biological oxygen demand and chemical oxygen demand of the coastal area are higher than those of the inland area indicating more domestic and industrial contamination. Total dissolved solid values across the region indicated fresh and brackish water for the coastal area and fresh water only for the inland area. The orders of abundance of the cations and anions for the coastal and inland areas are Ca>Mg>Na>K/Cl>HCO3>SO4>NO3 and Na>Ca>K>Mg/HCO3>Cl>NO3>SO4 respectively. A Piper diagram identified four hydrochemical facies, namely CaHCO3, NaHCO3, NaCl and CaMgClSO4. Ionic cross plots and correlation matrix revealed that the groundwater chemistry of the inland area is predominantly influenced by silicate weathering and ion exchange processes while those of the coastal area are influenced by silicate weathering, ion exchange processes and seawater tidal flushing. The groundwater from the coastal area is more polluted by heavy metals than those from the inland area. The observed variability may be attributed to effects of industrial wastes and exploration activities. In terms of water quality for domestic and irrigation, the groundwater of the coastal and the inland areas are not generally potable and suitable as drinking and irrigation water sources.

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