The current studies had already revealed the hydrocarbons could migrate from relatively high hydrocarbon potential stratum to shallow groundwater by corrosion emission and extraction emission in karst area and further impact on human health. Then, the comprehensive experiments were used to understand the mechanism and process of hydrocarbon emission as a continuation of a long-term study on original high hydrocarbon groundwater in shallow Triassic aquifer, taking northwest Guizhou, China, as a reference. The results determined water-rock interaction that lead to the hydrocarbon emission into groundwater with salinity acting as the main driving force. Relatively high salinity promotes the rock corrosion and hydrocarbon emission in the study area. The hydrocarbon emission process varied with different strata, as the results show that the hydrocarbon uniformly distributed in T₂g³ than that in T₁yn⁴. Furthermore, the stratum with uniformly distributed hydrocarbon would likely contain high hydrocarbon groundwater, as determined by the process of sedimentation. In addition, “corrosion rate estimation method” and “mineral constituent estimation method” were firstly employed to estimate the hydrocarbon concentration in groundwater to date. Compared with the hydrocarbon concentration of local groundwater samples (0 to 0.14 mg L⁻¹), the result of “mineral constituent estimation method” was analogous to measured value of groundwater samples in the area (0.05 to 0.50 mg L⁻¹), indicating the concentration of hydrocarbon could be estimated by mineral constitutions of groundwater, which was related to the concentration of Ca²⁺ and Mg²⁺. Based on the methods and theories in this study, the concentration of original hydrocarbon in shallow groundwater could be estimated and help to understand the mechanism of water-rock interaction in shallow aquifer and original high hydrocarbon groundwater strategic assessment.

This paper searches the role of financial sector development in energy sector and therefore in climate changes in the case of developing and developed countries. Panel data ranging from 1960 to 2014 on an annual basis has been selected from 176 countries. Results suggest that carbon dioxide emissions in developed and developing countries are in long-term equilibrium relationship with financial sector; trade and finance sectors have long-term significant impacts on carbon emissions and therefore carbon emissions converge to their long-term equilibrium levels through the channels of finance and trade sectors. Impulse response analyses proved that finance and trade sectors have negative (reducing) impact on the emission levels in the case of developed economies while they have positive impact in the case of developing economies. These sectors exert significant effects on energy consumption of countries as well. Results confirm that developed countries are more successful in energy conservation policies compared to developing countries. Therefore, authorities in developing countries need to implement conservation policies effectively by mainly encouraging and supporting investments in alternative energy uses in order to prevent increases in emission levels through expansion in financial and trade sectors.

The article Cellular distribution of cadmium in two amaranth (Amaranthus mangostanus L.) cultivars differing in cadmium accumulation, written by Keyu Chi, Rong Zou, Li Wang, Wenmin Huo and Hongli Fan, was originally published electronically on the publisher’s internet portal (currently SpringerLink)

Water environment monitoring is of great importance to human health, ecosystem sustainability, and water transport. Unlike traditional water quality monitoring problems, this paper focuses on visual perception of water environment. We first introduce the development of a customized aquatic sensor node equipped with an embedded camera sensor. Based on this platform, we present an efficient and holistic contamination detection approach, which can automatically adapt to the detection of floating debris in dynamic waters or the identification of salient regions in static waters. Our approach is specifically designed based on compressed sensing theory to give full consideration to the unique challenges in water environment and the resource constraints on sensor nodes. Both laboratory and field experiments demonstrate the proposed method can fast and accurately detect various types of water pollutants and is a better choice for camera sensor-based water environment monitoring compared with other methods.

We compared the concentrations of 17 heavy metals and essential elements in post-hatching eggshells of two waterbirds, the obligate piscivorous great cormorant Phalacrocorax carbo (GCM) and the more omnivorous grey heron Ardea cinerea (GHR), breeding sympatrically in eight mixed colonies in Poland. We found significant inter-species and inter-colony differences in the levels of most of the elements. GHR had significantly higher concentrations of Al, which can be explained by its very low stomach pH: an acidic environment favours the release of Al compounds. Differences in Mn, Ni, Cu, Se and Hg concentrations can be attributed to the various contributions of fish and other aquatic organisms to the diet, and to the exploration of different habitats (GCM exclusively aquatic, GHR a wider range) and microhabitats (GCM, in contrast to wading GHR, dive for food, exploring the whole depth range of water bodies), differently exposed to contamination by those elements from sediments. Inter-colony differences were related to the level of industrialisation. We recorded higher levels of some elements in the eggshells (Fe, Mn in both species and Cr, Ni and Zn in GCM) collected in industrialised areas, which may be associated with the negative environmental impact of industrial areas.

Düzce is one of the cities located in the western Black Sea region of Turkey with a population of 377,610 in 2017 (TUIK, 2017). There is no satisfying scientific information available to address the contribution of primary and secondary sources of carbonaceous aerosols to the observed PM₁₀ levels in the city. The main objective of the study is to determine the levels and sources of carbonaceous aerosols in PM₁₀. For this purpose, PM₁₀ samples were collected at urban and suburban locations in Düzce during winter and summer season in 2015. Average summer OC and EC concentrations in the urban area were 9.5 and 1.3 μg m⁻³, respectively, while the corresponding concentrations were observed as 28.5 and 2.3 μg m⁻³, respectively for winter season. Summer mean OC and EC levels at the suburban site were 5.46 and 0.37 μg m⁻³, respectively, while those for winter were found as 6.68 and 0.61 μg m⁻³.The contributions of OC and EC to measured PM₁₀ levels were found in the range of 10% to 60% and 1% to 7%, respectively, at the urban station while the associated contributions were in the range of 10% to 50% and 0.6% to 6%, respectively, at the suburban station. The concentrations measured during winter months in both areas were found to be higher than those measured during summer months. The EC tracer method was used in order to estimate the SOC contribution. The contribution of SOC concentrations to the total PM₁₀ mass was found to be higher during winter in the urban area and during summer in the suburban area.

The liver is one of the vital and sensitive organs which are usually exposed against the toxicity of mercury (Hg) and cadmium (Cd). The main objective of the current study was to evaluate the potential toxicological effects of both Cd and Hg as individual and combined. Hepatotoxicity was evaluated by monitoring the biochemical parameters of the liver and their accumulation in the liver as well as therapeutic role of vitamin C in said toxicity in rabbits (Oryctolagus cuniculus). In this research, cadmium chloride (1.5 mg/kg), mercuric chloride (1.2 mg/kg), and vitamin C (150 mg/kg of body weight) were orally administered to treatment groups of the rabbits for 28 alternative days. Various biochemical parameters of the liver such as lactate dehydrogenase (LDH), aspartate aminotransferase (ASAT), bilirubin, alanine aminotransferase (ALAT), total protein, and gamma glutamyl transferase (GGT) were estimated using blood samples. Some biochemical parameters like ASAT, ALAT, LDH, GGT, and bilirubin were significantly elevated (P ≤ 0.001) in individual Cd and Hg treatment groups, while the level of total protein was found to be significantly declined. The effects of Cd and Hg in the presence of vitamin C on these biochemical parameters were low as compared to metals-treated groups. Similar results were found when rabbits were treated with co-administration of both metals and vitamin C. Accumulation of Cd and Hg found to be higher in the liver. However, chemoprevention and chemotreatment with vitamin C significantly (P ≤ 0.01) minimized the toxicological effects of both metals but not regained the accumulation similar to that of the control group. The findings of this study provide awareness on accumulation of metals in the liver in rabbits and their toxicity tested through biochemical parameters as well as the therapeutic role of vitamin C in such alterations.

The sorption/desorption behaviors of benzene, toluene, ethylbenzene, and xylene (BTEX) on soil organic matter (SOM) have a significant influence on their fate and bioavailability in soil. Humic acid (HA) is a major fraction of SOM. And due to its various structural properties and chemical composition, the sorption/desorption characteristics and mechanisms of HA are diverse for organic contaminants. In this study, batch experiments were conducted to investigate the sorption/desorption behavior of benzene on HA at different conditions (temperature, pH, and ionic strength). The particle size of HA increased at lower initial pH which promoted sorption capacity for benzene, illustrating that HA with larger particle size may develop preferential chemical conformation for benzene sorption at lower pH. Sorption isotherms indicated that the sorption of benzene on HA is an exothermic and spontaneous physical process. And kinetic studies showed that the sorption of benzene on HA is controlled by the diffusion process and the availability of sorption sites. Meanwhile, weak sorbent-sorbate interaction is presented in the desorption experiment. There was no obvious effect of ionic strength on benzene sorption, suggesting that the sorption process is not controlled by ion-exchange or electrostatic interaction. Combined with FTIR analysis, the hydrophobic partitioning and π-π conjugative interaction are the possible sorption mechanisms of benzene on HA.

In this study, MODerate resolution Imaging Spectroradiometer (MODIS) Collection 6.1 (C6.1) level-2 Dark Target (DT) Aerosol Optical Depth (AOD) observations at 550 nm (AOD₅₅₀) for the highest quality flag assurance (QA = 3) were obtained to analyze spatiotemporal variations of aerosol optical properties over the Yellow and the Bohai Sea from 2002 to 2017. Spectral AOD observations at 470 nm (AOD₄₇₀) and 660 nm (AOD₆₆₀) were obtained to calculate Angstrom Exponent (AE₄₇₀–₆₆₀) and classify the aerosol types including clean continental (CC), clean maritime (CM) biomass and urban industrial (BUI), dust (D), and mixed (MXD) aerosol types. Results showed a very distinct spatial pattern of AOD distribution over the Bohai Sea which looks suspicious, i.e., high aerosol loadings (AOD > 0.8) throughout the entire time period, whereas relative low AOD distribution was observed over the adjacent land pixels especially in autumn and winter, which suggested that the DT algorithm might be influenced by a large number of sediments located in the Bohai Sea. Significant differences in spatial distributions were found in different seasons in terms of area coverage as a maximum number of pixels were available during autumn, and regional high and low aerosol loadings were observed during autumn and summer, respectively. Trend analysis from 2002 to 2017 showed that AOD was increased up to 0.04 over the Bohai Sea and decreased up to 0.04 over the Yellow Sea, and this trend varies from month to month. Aerosol classification showed significant contributions of BUI and CC over the region, and contributions of CM, DUST, and MXD aerosols over the Yellow Sea were relatively high compared to the Bohai Sea.

Carbon monoxide (CO) emission inventory data are crucial for air quality control. However, the emission inventories are labor-intensive and time-consuming and generally have large uncertainties. In this study, we developed a new regional data assimilation system (TracersTracker) for estimating the surface CO emission flux from continuous mixing ratio observations using the proper orthogonal decomposition (POD)-based four-dimensional variational (4D-VAR) data assimilation method (POD-4DVar) and a coupled regional model (Weather Research and Forecasting model (WRF) with the Models-3 Community Multi-scale Air Quality (CMAQ) model). This system was applied to estimate CO emissions in Xuzhou city, China. An experiment was conducted with the continuous hourly surface CO mixing ratio observations from 21 monitoring towers in January and July of 2016. The experimental results of the system were examined and compared with the continuous surface CO observations (a priori emission). We found that the retrieved CO emission fluxes were higher than the a priori emission and were mainly distributed in urban and industrial areas, which were 104% higher in January (winter) and 44% higher in July (summer).