Developing of theoretical tools can be very helpful for supporting new pollutant detection. Nowadays, a combination of mass spectrometry and chromatographic techniques are the most basic environmental monitoring methods. In this paper, two organochlorine compound mass spectra classification systems were proposed. The classification models were developed within the framework of artificial neural networks (ANNs) and fast 1D and 2D molecular descriptor calculations. Based on the intensities of two characteristic MS peaks, namely, [M] and [M-35], two classification criterions were proposed. According to criterion I, class 1 comprises [M] signals with the intensity higher than 800 NIST units, while class 2 consists of signals with the intensity lower or equal than 800. According to criterion II, class 1 consists of [M-35] signals with the intensity higher than 100, while signals with the intensity lower or equal than 100 belong to class 2. As a result of ANNs learning stage, five models for both classification criterions were generated. The external model validation showed that all ANNs are characterized by high predicting power; however, criterion I-based ANNs are much more accurate and therefore are more suitable for analytical purposes. In order to obtain another confirmation, selected ANNs were tested against additional dataset comprising popular sunscreen agents disinfection by-products reported in previous works.

Ozone (O₃) is an adverse environmental factor posing damage to ornamental plants. Thus, it is important to seek an effective way of enhancing plant tolerance to O₃-induced damage. Methyl jasmonate (MJ) and melatonin (MT) are plant growth regulators (PGRs) involved in plant abiotic stress responses. In this study, compared with the control group of plants without ozone, the influence of exogenous MJ (0, 10, 50, 100, and 150 μM) and MT (0, 0.1, 0.5, 2.5, and 12.5 μM) on the resistance of Malus crabapple ‘Hong Jiu’ was evaluated under O₃ stress (100 ± 10 nL/L for 3 h). Our data revealed that levels of MDA were significantly enhanced following O₃ treatment compared with plants without O₃. O₃ induced the activities of antioxidant enzymes and the accumulation of non-enzymatic antioxidants. While lower malondialdehyde (MDA) content, greater activities of antioxidant enzymes, and higher levels of soluble protein and non-enzymatic antioxidants were observed in PGRs-pretreated plants than in non-PGRs-pretreated plants under O₃ stress. Based on the above results and air pollution tolerance index (APTI), an exogenous supply of MJ and MT to Malus crabapple ‘Hong Jiu’ seedlings was protective for O₃-induced toxicity. The present study provides new insights into the mechanisms of MJ and MT amelioration of O₃-induced oxidative stress damages in Malus crabapple ‘Hong Jiu.’

Mosses can be used as biomonitors to monitor radionuclide deposition and heavy metal pollution in cities, forests, and grasslands. The aims of this work were to determine the activity concentrations of natural (²¹⁰Po, ²¹⁰Pb or ²¹⁰Pbₑₓ (excess ²¹⁰Pb is defined as the activity of ²¹⁰Pb minus the activity of ²²⁶Ra), ⁷Be, ⁴⁰K, ²²⁶Ra, ²³⁸U, and ²³²Th) and anthropogenic radionuclides (¹³⁷Cs) in moss body profiles and in situ underlying soils of moss samples and to assess/determine the distribution features and accumulation of these radionuclides. Activity concentrations of radionuclides in the samples were measured using a low-background gamma spectrometer and a low-background alpha spectrometer. Consistent with their source, the studied radionuclides in the moss samples and underlying soils were divided according to the principal component analysis (PCA) results into an airborne group (²¹⁰Po, ²¹⁰Pb (²¹⁰Pbₑₓ), ⁷Be, and ¹³⁷Cs) and a terrestrial group (⁴⁰K, ²³⁸U, ²²⁶Ra, and ²³²Th). The activity concentrations of ²¹⁰Po and ²¹⁰Pbₑₓ in moss body profiles were mainly concentrated in the stems–rhizoid parts, in which we measured some of the highest ²¹⁰Po and ²¹⁰Pbₑₓ levels compared to the results in the literature. ⁷Be mainly accumulated in the leaves–stem parts. Different positive correlations were observed between ²¹⁰Po and ²¹⁰Pb and between ⁷Be and ²¹⁰Pb, which indicated that the uptake mechanisms of ²¹⁰Po, ²¹⁰Pb, and ⁷Be by moss plants were different, to some extent. ¹³⁷Cs was detected only in some moss samples, and the fraction of ¹³⁷Cs in the underlying soils was much lower than that in the moss, suggesting that mosses were protecting the underlying soils from further pollution. Except for ⁴⁰K, the terrestrial radionuclide (²³⁸U, ²²⁶Ra, and ²³²Th) content in mosses was predominantly at low levels, which indicated not only the inability of mosses to use those elements for metabolic purposes but also the rather poor capability of mosses to directly mobilize, absorb, and transport elements (U, Ra, or Th) not dissolved in water.

Toxic metal contamination in food products and the environment is a public health concern. Therefore, understanding human exposure to cadmium (Cd), lead (Pb), cobalt (Co), and copper (Cu) levels in the general population of Taiwan is necessary and urgent. We aimed to establish the human biomonitoring data of urine toxic metals, exposure profile changes, and factors associated with metal levels in the general population of Taiwan. We randomly selected 1601 participants older than 7 years of age (36.9 ± 18.7 years (7–84 years)) from the Nutrition and Health Survey in Taiwan (NAHSIT) conducted during 1993–1996 (93–96) and 2005–2008 (05–08) periods and measured the levels of four metals in the participants’ urine samples using inductively coupled plasma-mass spectrometry. The median (range) levels of urinary Cd, Pb, Co, and Cu in participants from the NAHSIT 93–96 (N = 821)/05–08 (N = 780) were 0.60 (ND–13.90)/0.72 (ND–7.44), 2.28 (ND–63.60)/1.09 (0.04–48.88), 0.91 (0.08–17.30)/1.05 (0.05–22.43), and 16.87 (2.62–158.28)/13.66 (1.67–189.70) μg/L, respectively. We found that the urinary median levels of Pb and Cu in our participants were significantly lower in the NAHSIT 05–08 (Pb 1.09 μg/L, Cu 13.66 μg/L) than in the NAHSIT 93–96 (Pb 2.28 μg/L, Cu 16.87 μg/L; P < 0.01), whereas those of Cd and Co were significantly higher in the NAHSIT 05–08 (Cd 0.72 μg/L, Co 1.05 μg/L; P < 0.01). Youths had higher exposure levels of Pb, Co, and Cu than adults. Participants with alcohol consumption, betel quid chewing, or cigarette smoking had significantly higher median levels of urinary Pb or Cu (P < 0.01) than those without. Principal components and cluster analysis revealed that sex had different exposure profiles of metals. We concluded that levels of urinary Cd, Pb, Co, and Cu exposure in the general Taiwanese varied by age, sex, and lifestyles.

The port regions of the Amazon are subject to environmental impacts high shipping traffic. In October 2015, a cargo ship containing 5000 oxen sank in the Port of Vila do Conde, northern Brazil, releasing large amounts of organic matter and diesel oil into the aquatic environment. We evaluated the consequences of this shipwreck on the zooplankton community. Sampling was carried out using a phytoplankton net (64 μm) at two locations close to the port. We calculated the frequency of occurrence, relative abundance, and trophic state index and performed a canonical redundancy analysis of zooplankton in this area. Total density values ranged from 371 to 8600 organisms/m³, with minimum values being recorded during the period of the shipwreck and maximum values after the shipwreck. The areas categorized as super eutrophic had the lowest density values. The most abundant species/groups were nauplii and copepodites of the orders Cyclopoida and Calanoida. Of the environmental variables, only biochemical oxygen demand, chemical oxygen demand, and total dissolved solids were selected by the redundancy canonical analysis. The environmental conditions of the region and the ongoing environmental impacts might substantially influence the structure of the zooplankton community. The predominance of these organisms, in addition to the high densities of nauplii and copepodites, was likely related to the large amounts of nutrients generated by the shipwreck.

Climate change adversely affects food security all over the world, especially in developing countries where the increasing population is confronting food insecurity and malnutrition. Crop models can assist stakeholders for assessment of climate change in current and future agricultural production systems. The aim of this study was to use of system analysis approach through CSM-CERES-Millet model to quantify climate change and its impact on pearl millet under arid and semi-arid climatic conditions of Punjab, Pakistan. Calibration and evaluation of CERES-Millet were performed with the field observations for pearl millet hybrid 86M86. Mid-century (2040–2069) climate change scenarios for representative concentration pathway (RCP) 4.5 and RCP 8.5 were generated based on an ensemble of selected five general circulation models (GCMs). The model was calibrated with optimum treatment (15-cm plant spacing and 200 kg N ha⁻¹) using field observations on phenology, growth and grain yield. Thereafter, pearl millet cultivar was evaluated with remaining treatments of plant spacing and nitrogen during 2015 and 2016 in Faisalabad and Layyah. The CERES-Millet model was calibrated very well and predicted the grain yield with 1.14% error. Model valuation results showed that there was a close agreement between the observed and simulated values of grain yield with RMSE ranging from 172 to 193 kg ha⁻¹. The results of future climate scenarios revealed that there would be an increase in Tₘᵢₙ (2.8 °C and 2.9 °C, respectively, for the semi-arid and arid environment) and Tₘₐₓ (2.5 °C and 2.7 °C, respectively, for the semi-arid and arid environment) under RCP4.5. For RCP8.5, there would be an increase of 4 °C in Tₘᵢₙ for the semi-arid and arid environment and an increase of 3.7 °C and 3.9 °C in Tₘₐₓ, respectively, for the semi-arid and arid environment. The impacts of climate changes showed that pearl millet yield would be reduced by 7 to 10% under RCPs 4.5 and 8.5 in Faisalabad and 10 to 13% in Layyah under RCP 4.5 and 8.5 for mid-century. So, CSM-CERES-Millet is a useful tool in assessing the climate change impacts.

The original publication of this paper contains a mistake. Unfortunately, an author was inadvertently missed out, Constanza Arriagada had participated in the operation of the anaerobic digesters cited in the work and now as a PhD student, she is involved in the production of other publication

Diclofenac (DCF), a widely used non-steroidal anti-inflammatory drug, has been detected in effluents of conventional wastewater treatment plants worldwide. The presence of this compound in various water resources even at very low concentrations poses a big threat both to human health and aquatic ecosystems. In this study, the removal of diclofenac from aqueous solution using Fe–Mn binary oxide (FMBO) adsorbents was investigated. FMBO adsorbents were prepared at varying Fe/Mn molar ratios (1:0, 3:1, and 1:1) through simultaneous oxidation and co-precipitation methods. Batch adsorption experiments were conducted to evaluate the effects of important parameters, such as initial DCF concentration, FMBO dosage, solution pH, and Fe/Mn molar ratio, on DCF removal. Acidic to neutral pH conditions were more favorable for DCF adsorption, while increasing initial DCF concentration and adsorbent dosage resulted in higher DCF removal efficiencies for the three oxides. Lower Fe/Mn molar ratio during FBMO synthesis favored higher DCF removals of up to 99% within a wide pH range. Optimization of operating parameters (initial DCF concentration, FMBO dosage, and solution pH) by Box–Behnken design resulted in up to 28.84 mg g⁻¹ DCF removal for 3:1 FMBO. Freundlich isotherm best described the experimental data, indicating that adsorption occurred on heterogeneous adsorbent surface. Chemisorption was the rate-limiting step of the DCF removal, as best described by the pseudo-second-order kinetic model.

Increasing agricultural production requires the application of more chemical inputs during the growth of different crops. This study aims at assessing the energy indicators and environmental impacts during the initial 7-year growth of orange orchards. Through the life cycle assessment (LCA) technique, the hotspots in 11 environmental indicators of the orange orchard growth were determined for different years. The system boundaries were considered to be the orange orchard gates, and the functional units were 1 kg of orange and 1-h orange orchard. The energy input of nitrogen fertilizer, diesel, and human labor has the biggest share in the total energy inputs. The total average energy input and energy output (in 7 years) were calculated as 62,917.027 MJ/ha and 47,618.17 MJ/ha, respectively. The results showed that the energy indices (energy efficiency and net energy) were increasing from year first to seventh and also the share of renewable energy increased. According to the results, with respect to the highest share for production of 1 kg orange in different criteria, nitrogen fertilizer was the main contributor to abiotic depletion and human toxicity, orchard field emissions and nitrogen fertilizer had the highest shares in global warming and photochemical oxidation, fossil fuels and nitrogen fertilizer were the highest contributors to ozone layer depletion, whereas ecotoxicity was mainly affected by chemical fertilizers and orchard surface emissions. Finally, the main contributor for acidification and eutrophication was surface emissions. In the study of environmental impacts from the first to the seventh year, it should be noted that if the functional unit is considered mass based (1 kg orange), due to the unproductive of the trees in the first to third years (low fruit production), the environmental effects are high and then it decreases after the third year due to increasing the yield of the product. Generally, with consideration of the tree growth period, the useful data of energy and environmental impacts for production horticultural products can be provided so that we can avoid multiple interpretations of results associated to reporting annual energy and environmental impact variations.

Karst processes play an important role in the global carbon cycle. Aquatic phototrophs can transform bicarbonate, which is mainly derived from the weathering of carbonates, into organic carbon. Carbonate mineral weathering coupled with aquatic photosynthesis can be considered a stable and durable carbon sink process. In this study, we addressed seasonal variations in water chemistry in the Lijiang River Basin, which is a typical karst basin, through a comprehensive geochemical study of the river water in four seasons. The parameters were measured in situ, including major ions and isotopes of inorganic and organic carbon. The results showed that (1) DIC was mainly derived from the weathering of carbonates; (2) the transformation from bicarbonate to organic carbon by aquatic phototrophs was evident, and the water chemistry changed, especially in spring and autumn and in the mainstream from Guilin to Yangshuo, which benefited the growth of aquatic phototrophs; and (3) the organic carbon derived from bicarbonates by aquatic phototrophs was nearly half the total organic carbon and 8% of the dissolved inorganic carbon. These results imply that aquatic phototrophs in karst basins can significantly stabilize carbon originating from carbonate rock weathering processes in karst areas.