The use of lichens as ecological surrogates has been an important tool to evaluate the impact of air pollution in both ecosystem and human health but remains underused in the subtropics due to lack of knowledge. Aiming to support the application of lichen as ecological surrogates of the effects of air pollution in the subtropics, we hypothesized that urbanization was an important driver of changes on lichen diversity, composition, and vitality. For that, we quantified several lichen diversity metrics (richness, cover, and community composition) and photobiont vitality in relation to atmospheric pollution or its surrogates (modeled pollutant gases, pollutants in lichen thallus, and land cover). We confirmed that air pollution was a key driver for lichen diversity. Changes in lichen community composition and vitality were very significantly related to air pollution and integrated the effect of multiple stressors (particulate matter, NOx, and Cu), thus being powerful ecological indicators of air pollution in the subtropics.

Rare earth (Dy³⁺ and Sm³⁺)-doped sodium magnesium borate (NaMgBO₃) is synthesized by solution combustion synthesis method keeping their thermoluminescence properties in mind. The reaction produced very stable crystalline NaMgBO₃:RE (RE = Dy³⁺, Sm³⁺) phosphors. The phosphors are exposed to ⁶⁰Co gamma-ray radiations dose of varying rate from 5 to 25 Gy, and their TL characteristics with kinetic parameters are studied. NaMgBO₃:Dy³⁺ phosphor shows two peaks for lower doping concentration of Dy³⁺ while it reduced to single peak for the higher concentrations of activator Dy³⁺. NaMgBO₃:Dy³⁺ shows the major glow peak around 200 °C while NaMgBO₃:Sm³⁺ phosphors show two well-separated glow peaks at 200 and 332 °C respectively. The thermoluminescence intensity of these phosphors was compare with the commercially available TLD-100 (Harshaw) phosphor. The TL responses for gamma-ray radiations dose were found to be linear from 5 to 25 Gy for both phosphors while the fading in each case is calculated for the tenure of 45 days.

Chlordecone, an organochlorine insecticide, pollutes soils and contaminates crops and water resources and is biomagnified by food chains. As chlordecone is partly trapped in the soil, one possible alternative to decontamination may be to increase its containment in the soil, thereby reducing its diffusion into the environment. Containing the pesticide in the soil could be achieved by adding compost because the pollutant has an affinity for organic matter. We hypothesized that adding compost would also change soil porosity, as well as transport and containment of the pesticide. We measured the pore features and studied the nanoscale structure to assess the effect of adding compost on soil microstructure. We simulated changes in the transport properties (hydraulic conductivity and diffusion) associated with changes in porosity. During compost incubation, the clay microstructure collapsed due to capillary stresses. Simulated data showed that the hydraulic conductivity and diffusion coefficient were reduced by 95 and 70 % in the clay microstructure, respectively. Reduced transport properties affected pesticide mobility and thus helped reduce its transfer from the soil to water and to the crop. We propose that the containment effect is due not only to the high affinity of chlordecone for soil organic matter but also to a trapping mechanism in the soil porosity.

This study investigated the treatment performance for aging leachate containing refractory organic pollutants by TiO₂-organobentonite photocatalyst combined with polyaluminum chloride (PAC) coagulant. TiO₂ was immobilized on organobentonite granules as a supporter modified by cetyltrimethylammonium chloride (CTAC). The prepared catalysts were characterized by ESEM, FTIR, and XRD analysis, which showed that TiO₂-organobentonite catalyst had uniform coating of TiO₂ on support. Chemical oxygen demand (COD) and NH₃-N removal rates by combination of TiO₂-CTAC2.0 photocatalysis and PAC coagulation were evaluated, optimized, and compared to that by either treatment alone, with respect to TiO₂-CTAC2.0 dose, photocatalytic contact time, pH, and PAC dose. Furthermore, higher removal rates (COD 80 %; NH₃-N 46 %) were achieved by response surface methodology (RSM) when TiO₂-CTAC2.0 photocatalysis was followed by PAC coagulation at optimized conditions. The optimized experimental conditions were TiO₂-CTAC2.0 dosage of 5.09 g/L, at pH 5.53, photocatalytic contact time for 180 min, and PAC dosage of 1062 mg/L.

Shifting cultivation (jhum) is a major land use practice in Mizoram. It was considered as an eco-friendly and efficient method when the cycle duration was long (15–30 years), but it poses the problem of land degradation and threat to ecology when shortened (4–5 years) due to increased intensification of farming systems. Studying beetle community structure is very helpful in understanding how shifting cultivation affects the biodiversity features compared to natural forest system. The present study examines the beetle species diversity and estimates the effects of shifting cultivation practices on the beetle assemblages in relation to change in tree species composition and soil nutrients. Scarabaeidae and Carabidae were observed to be the dominant families in the land use systems studied. Shifting cultivation practice significantly (P < 0.05) affected the beetle and tree species diversity as well as the soil nutrients as shown by univariate (one-way analysis of variance (ANOVA), correlation and regression, diversity indices) and multivariate (cluster analysis, principal component analysis (PCA), detrended correspondence analysis (DCA), canonical variate analysis (CVA), permutational multivariate analysis of variance (PERMANOVA), permutational multivariate analysis of dispersion (PERMDISP)) statistical analyses. Besides changing the tree species composition and affecting the soil fertility, shifting cultivation provides less suitable habitat conditions for the beetle species. Bioindicator analysis categorized the beetle species into forest specialists, anthropogenic specialists (shifting cultivation habitat specialist), and habitat generalists. Molecular analysis of bioindicator beetle species was done using mitochondrial cytochrome oxidase subunit I (COI) marker to validate the beetle species and describe genetic variation among them in relation to heterogeneity, transition/transversion bias, codon usage bias, evolutionary distance, and substitution pattern. The present study revealed the fact that shifting cultivation practice significantly affects the beetle species in terms of biodiversity pattern as well as evolutionary features. Spatiotemporal assessment of soil–plant–beetle interactions in shifting cultivation system and their influence in land degradation and ecology will be helpful in making biodiversity conservation decisions in the near future.

Vanadium oxide-based catalysts were developed for the destruction of vapour phase PCDD/Fs (polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans). A vapour phase PCDD/Fs generating system was designed to supply stable PCDD/Fs steam with initial concentration of 3.2 ng I-TEQ Nm⁻³. Two kinds of titania (nano-TiO₂ and conventional TiO₂) and alumina were used as catalyst supports. For vanadium-based catalysts supported on nano-TiO₂, catalyst activity is enhanced with operating temperature increasing from 160 to 300 °C and then reduces with temperature rising further to 350 °C. It is mainly due to the fact that high volatility of organic compounds at 350 °C suppresses adsorption of PCDD/Fs on catalysts surface and then further inhibits the reaction between catalyst and PCDD/Fs. The optimum loading of vanadium on nano-TiO₂ support is 5 wt.% where vanadium oxide presents highly dispersed amorphous state according to the Raman spectra and XRD patterns. Excessive vanadium will block the pore space and form microcrystalline V₂O₅ on the support surface. At the vanadium loading of 5 wt.%, nano-TiO₂-supported catalyst performs best on PCDD/Fs destruction compared to Al₂O₃ and conventional TiO₂. Chemical states of vanadium in the fresh, used and reoxidized VOx(5 %)/TiO₂ catalysts at different operating temperature are also analysed by XPS.

The greater the use of energy in the transportation sectors, the higher the emission of carbon monoxide (CO), and hence inevitable harm to environment and human health. In this concern, measuring and predicting of CO emission from transportation sector—especially large cities—is important as it constitute 90 % of all CO emission. Many urban cities in developing world have not properly experienced such measurements or predictions. In this paper, for the first time, field measurements of traffic characteristics data and corresponding CO concentration have been performed for developing a model for predicting CO emissions from transportation sector for New Borg El Arab (NBC), Egypt. The performance of Swiss-German Handbook Emission Factors for Road Transport (HBEFA v3.1) model has been assessed for predicting the CO concentration at roadside in the study area. Results indicated that HBEFA v3.1 underestimate emission figures. The developed CO dynamic emission model involves the traffic flow characteristics with roadside CO concentrations. Acceptable representation of measured CO concentration has been shown by the developed dynamic CO emission model which introduces R ² = 0.77, mean biases and frictional biases of −0.27 mg m⁻³ and 0.09, respectively. A comparison between predicted CO concentrations using HBEFA v3.1 and the promoted dynamic model indicate that HBEFA v3.1 estimates CO emission concentrations in the study area with a mean error and frictional biases 159.26 and 233.33 %, respectively, higher than those of the developed model.

The present study used commercial feeds, food waste feeds, Napier grass, and mixed feeds (food waste feed to Napier grass ratio, 1:10) to feed grass carp (Ctenopharyngodon idellus). The results indicated that grass carp fed with food waste feeds and mix feeds achieved growth performance (based on specific growth rate and feed conversion ratio) that was similar to commercial feeds (p > 0.05). Concentrations of metalloid/metals in food waste feeds and polycyclic aromatic hydrocarbons (PAHs) in Napier grass were relatively higher than other types of fish feeds (p < 0.05). However, most of the metalloid/metals and PAH levels in fish fed with four types of fish feeds were not significantly different (p > 0.05). These findings show that food waste feeds are suitable for using in the production of fish feed and Napier grass can be served as supplemental feeds for grass carp, and hence reducing the production cost.

The tannery industry is a major source of anthropogenic chromium (Cr) contamination due to the large amounts of solid waste produced and its problematic management. The unique composition of tannery waste, usually high concentrations of Cr and other metals as well as organic matter and nutrients, makes it a great risk for soil and water environment but also a possible effective fertilizer for non-food plants that can tolerate metals. The goal of this study was to understand the adaptation mechanism of Salix viminalis to growth on Cr-rich tannery waste from an active landfill. We used a proteomic approach to identify leaf and fine roots proteins altered by tannery waste as compared to control soil conditions. We found no obvious symptoms of oxidative stress in leaves or fine roots. Proteomic results indicated some changes in metabolism, with increases in energy production processes and their greater efficiency for leaves rather than root development. Comparison between S. viminalis and P. × canescens response to tannery waste suggested that S. viminalis is not suitable for remediation of Cr-contaminated areas of a tannery waste landfill site.

Surface sediment-associated synthetic pyrethroid insecticides (SPs) are known to pose high risks to the benthic organisms in Chaohu Lake, a shallow lake of Eastern China. However, the pollution status of the lake’s tributaries and estuaries is still unknown. The present study was conducted to investigate the occurrence, compositional distribution, and toxicity of 12 currently used SPs in the surface sediments from four important tributaries, as well as in the sediment cores at their estuaries, using GC-MS for quantification. All SPs selected were detectable, with cypermethrin, es/fenvalerate, and permethrin dominant in both surface and core sediments, suggesting that these compounds were extensively applied. Urban samples contained the highest summed concentrations of the 12 SPs analyzed (Σ₁₂SP) in both surface and core sediments compared with rural samples, suggesting that urban areas near aquatic environments posed high risks for SPs. The mean concentration of Σ₁₂SP in surface sediments of each river was generally higher than that found in core sediments from its corresponding estuary, perhaps implying recent increases in SP usage. Surface sediments were significantly dominated by cypermethrin and permethrin, whereas core sediments were dominated by permethrin and es/fenvalerate. The compositional distributions demonstrated a spatial variation for surface sediments because urban sediments generally contained greater percentages of permethrin and cypermethrin, but rural sediments had significant levels of es/fenvalerate and cypermethrin. In all sediment cores, the percentage of permethrin gradually increased, whereas es/fenvalerate tended to decrease, from the bottom sediments to the top, indicating that the former represented fresh input, whereas the latter represented historical residue. Most urban samples would be expected to be highly toxic to benthic organisms due to the residue of SPs based on a calculation of toxic units (TUs) using toxicity data of the amphipod Hyalella azteca. However, low TU values were found for the samples from rural areas. These results indicate that the bottom sediments were exposed to high risk largely by the residual SPs from urban areas. The summed TUs were mostly attributable to cypermethrin, followed by λ-cyhalothrin and es/fenvalerate. Despite permethrin contributing ∼28.7 % of the Σ₁₂SP concentration, it only represented 6.34 % of the summed TUs. Therefore, our results suggest that high levels of urbanization can increase the accumulation of SPs in aquatic environments.