Vegetation is a natural tie that connects the atmosphere, hydrosphere, biosphere, and pedosphere. Quantitatively evaluating the variability of vegetation coverage and exploring its associated influence factors are essential for ecological security and sustainable economic development. In this paper, the spatiotemporal variation of vegetation coverage and its response to climatic factors and land use change were investigated in the Yangtze River Delta (YRD) from 2001 to 2015, based on normalized difference vegetation index (NDVI) data, vegetation type data, climate data, and land use/cover change (LUCC) data. The results indicated that the annual mean vegetation coverage revealed a nonsignificant decreasing trend over the whole YRD. Areas characterized by significant decreasing (P < 0.05) trends were mainly concentrated on the central and northern part of the YRD, and significant increasing (P < 0.05) trends were mainly located in the southern part of the study area. Except for grassland and cultivated crops, vegetation coverage of the other types of vegetation was all exhibiting increasing trends. Temperature has a more pronounced impact on vegetation growth than precipitation at both the annual and monthly scales. Furthermore, vegetation growth exhibited a time lag effect for 1~2 months in response to precipitation, while there was no such phenomenon with temperature. Land use change caused by urbanization is an important driving factor for the decrease of vegetation coverage in the YRD, and the effect of land use change on the vegetation dynamic should not be overlook.

Over the past years, there were dramatic improvements in identifying and assessing various feedstocks for the production of biodiesel fuels. To promote a particular feedstock as a renewable source of energy, it is important to analyze their energy, economic, and engine performance characteristics. The current work attempts to evaluate the net energy and economic indices for both fossil diesel and coconut-blended diesel (B20) considering the diesel consumption by the Indian railways. Further, we present the experimental results of a multi-cylinder diesel engine operated with neat coconut biodiesel (B100) and fossil diesel at various load and speed conditions. The engine experiments reveal that the coconut biodiesel exhibits leaner combustion and shorter ignition delay than fossil diesel. Lower amount of carbon monoxide, hydrocarbon, and smoke emission is observed in the case of coconut biodiesel, with higher levels of nitric oxide (14%) and fuel consumption than diesel. The coefficient of variation in indicated mean effective pressure is within the range of better driveability zone for both the fuels at all test conditions. Overall the engine performance, emission and combustion results with neat coconut biodiesel are favorable with a penalty in NO emission at high load conditions. The techno-economical study highlights higher production cost per liter of B20 than the cost of fossil diesel. However, the net energy ratio (NER) for B20 is 1.021, favoring higher output than diesel and thus lowers the dependency on crude oil.

There are mounting evidences indicated that maternal exposure to outdoor air pollutants in pregnancy affects children’s neural development, but the researches on children’s behavioral difficulties are seldom. We explored the association between maternal exposure to outdoor air pollution during different trimesters of pregnancy and the prevalence of behavioral difficulties among 657 preschool children aged 3–4 from three kindergartens in Wuhan, China. This is a cross-sectional study. Children’s behavioral difficulties were assessed by the Strengths and Difficulties Questionnaire (SDQ) (reported by parents). Maternal exposure to outdoor air pollutants during pregnancy were estimated based on the daily average measured concentration levels from ground monitoring stations. Potential confounding factors including children-related, maternal, and socio-economic status (SES) were adjusted in the study. We calculated the prevalence of each type of behavioral difficulties and used binary logistic regression method to estimate the crude odds ratio (cOR), adjusted odds ratio (aOR), and corresponding 95% confidence intervals (95% CIs) for 1 μg/m³ increase in each air pollutant during every exposure window in single- and two-pollutant models. The prevalence of participants’ total behavioral difficulties was 9.6%. In single-pollutant models, during full gestation, positive associations were observed between exposure to NO₂ (aOR = 1.204, 95% CI 1.042, 1.392), particle matter (PM)₁₀ (aOR = 1.070, 95% CI 1.018, 1.125), PM₂.₅ (aOR = 1.095, 95% CI 1.021, 1.176) and total difficulties, exposure to PM₁₀ (aOR = 1.040, 95% CI 1.001, 1.081), PM₂.₅ (aOR = 1.053, 95% CI 1.000, 1.109) and prosocial behavior, respectively. In the first trimester, exposure to SO₂ (aOR = 1.047, 95% CI 1.009, 1.086), NO₂ (aOR = 1.039, 95% CI 1.013, 1.066), PM₁₀ (aOR = 1.013, 95% CI 1.004, 1.023), and PM₂.₅ (aOR = 1.016, 95% CI 1.004, 1.028) were all positively associated with total difficulties. The associations between second and third trimesters’ exposure to all pollutants and outcomes were not statistically significant. However, in the two-pollutant models, second trimester exposure to PM₂.₅ (aOR = 1.078, 95%CI 1.023, 1.137) was positively associated with total behavioral difficulties after adjusting for PM₁₀. Exposure to outdoor air pollutants SO₂, NO₂, PM₁₀, and PM₂.₅ during pregnancy may be associated with behavioral difficulties, especially in the first trimester.

The occurrence of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in the atmosphere of six sites with different emission sources in the province of Córdoba, Argentina, was analyzed. The sites included urban, industrial, agricultural, and mountain areas. Samples were collected using passive air samplers (PAS) consisting of polyurethane foam disks (PUF). Samples were analyzed for 12 PAHs, 31 polychlorinated biphenyls (PCBs), 12 organochlorine pesticides (OCPs), and 11 polybrominated diphenyl ethers (PBDEs). The concentrations of PAHs in the atmosphere were elevated at urban sites and were even higher at the industrial site. With respect to OCPs, it was observed that the concentrations of endosulfan were greater at the agricultural site (AGR) (416 ± 4 pg m⁻³). For hexachlorocyclohexanes (HCHs), only the alpha isomer was detected and there were minimal differences between the different sampling sites (5.9–13.3 pg m⁻³). In the case of dieldrin, the highest concentrations (33.6 pg m⁻³) were found at the mountain site, which may have been due to its use for insect control. Although heptachlor epoxide was not detected, the concentration of heptachlor was significantly higher at the agricultural and downtown sites (∼ 3.6 pg m⁻³). Regarding DDTs, the isomers p,p′-DDT and p,p′-DDE showed the highest concentrations at the mountain site (ΣDDT 120 ± 12 pg m⁻³) and downtown site (ΣDDT 157 ± 62 pg m⁻³). The relationship between the isomers suggested that at the downtown site, the contribution of this pesticide to the environment was recent, probably for the control of diseases vectors. The congener pattern of PBDEs was dominated by BDE-47, and BDE-99 at all sites, with the downtown site having the highest concentrations of compound esters (ΣPBDEs 118 ± 38 pg m⁻³). Finally, high concentrations of PCBs were found at the industrial site (ΣPCBs 1677 ± 134 pg m⁻³), and the predominating homologs were 5-Cl and 6-Cl, in contrast to the other sites where PCBs were dominated by 3-Cl and 4-Cl. This is the first study of POPs carried out in the province of Córdoba.

The purpose of this study is to evaluate the health effect of heavy metal pollution in air pollutants on traffic policemen. This study will facilitate the scientific evaluation of health status of traffic policemen. PM₁₀ samples were collected from industrial area, congested traffic area and residential area respectively in Nanchang City, and the concentrations of heavy metals were analyzed. The traffic policemen were examined through chest X-rays. The total of 637 urine samples and 142 blood samples have been collected, and the concentrations of Pb in samples were detected. Vehicle flux data of Nanchang City were collected from the Department of Transport’s Traffic Management. Statistic analyses were carried out by statistics software of Excel 2003 and SPSS20.0, and the health effect of heavy metal pollution of PM₁₀ on the traffic policemen was evaluated. The discharge of pollutants from enterprises is an important reason for the high content of heavy metals in urban air pollution. With the rapid growth of urban traffic flow, Bayi Bridge becomes an important transportation hinge in Nanchang City, and the bidirectional traffic flow rate through the bridge at peak hours reached 99 vehicles per minute. The latent hazard of occupational harm on the traffic policemen caused by automobile exhaust is increasing. The concentration of Pb in the urine and blood samples from traffic policemen working in Nanchang City was 268.310 ± 177.031 and 22.873 ± 21.137 μg/L, respectively. Both results (2.04% of Pb in urine and 18.31% of Pb in blood) exceeded the highest limit of observed occupationally outdoor workers. This study provides an initial contribution for the assessment of city air pollution, esp. the health effect of heavy metal (Pb) pollution on traffic policemen.

Monitoring the amount and composition of airborne particulate matter (PM) in the urban environment is a crucial aspect to guarantee citizen health. To focus the action of stakeholders in limiting air pollution, fast and highly spatially resolved methods for monitoring PM are required. Recently, the trees’ capability in capturing PM inspired the development of several methods intended to use trees as biomonitors; this results in the potential of having an ultra-spatially resolved network of low-cost PM monitoring stations throughout cities, without the needing of on-site stations. Within this context, we propose a fast and reliable method to qualitatively and quantitatively characterize the PM present in urban air based on the analysis of tree leaves by scanning electron microscopy combined with X-ray spectroscopy (SEM/EDX). We have tested our method in the Real Bosco di Capodimonte urban park (Naples, Italy), by collecting leaves from Quercus ilex trees along transects parallel to the main wind directions. The coarse (PM₁₀–₂.₅) and fine (PM₂.₅) amounts obtained per unit leaf area have been validated by weighting the PM washed from leaves belonging to the same sample sets. PM size distribution and elemental composition match appropriately with the known pollution sources in the sample sites (i.e., traffic and marine aerosol). The proposed methodology will then allow the use of the urban forest as an ultra-spatially resolved PM monitoring network, also supporting the work of urban green planners and stakeholders.

This paper investigates the impact of tourism investments on energy efficiency across the transportation and residential sectors of 32 Organization for Economic Co-operation and Development economies. Using annual data from 1995 to 2012, we employ various panel econometric techniques to achieve the study objectives. Given the nature of variables, the paper applies panel autoregressive distributed lag models to estimate the long-run elasticities of energy intensity. The long-run estimates confirm that tourism investments play an essential role in improving energy efficiency across the transportation and residential sectors. Furthermore, the results show that both the foreign direct investment inflows and trade openness also play a considerable role in reducing energy uses across these sectors. Finally, the findings suggest that the tourism investments Granger cause energy efficiency of transportation and residential sectors in the short-run. Given these findings, the paper adds considerable value to the empirical literature and also provides various policy- and practical implications.

The objective of this paper was to study the pore-size distribution of municipal solid waste (MSW) and provide a basis for understanding the mechanism of preferential flow in MSW. Two methods were used to investigate the pore-size distribution in MSW. The first was an indirect method based on the soil-water characteristic curve (SWCC) and the second was a direct method using nuclear magnetic resonance (NMR). Samples taken from different depths of a landfill were used. In the SWCC method, SWCCs of the matrix region were obtained by a pressure plate extractor and SWCCs of the macropore region were determined by water breakthrough tests. A SWCC equation is proposed by modifying the Van Genuchten equation to consider the dual-porosity feature of MSW and the pore-size distribution was obtained based on the Young–Laplace equation. In the NMR method, the pore-size distribution of MSW was obtained by analyzing the T₂ curves. The results of the two methods were qualitatively similar and both showed a dual-porosity characteristic of MSW. The average macropore radii of shallow, middle, and deep MSWs obtained from the SWCC method are 0.193, 0.184, and 0.173 mm, and those obtained from the NMR method are 0.213, 0.138, and 0.145 mm, respectively. The proportion of macropores decreases with depth. The average micropore radii given by the SWCC method are 0.022, 0.011, and 0.008 mm, and those given by the NMR method are 0.013, 0.011, and 0.008 mm, respectively. As the depth and fill age increase, the average micropore size becomes smaller and the proportion of micropores increases. The volume ratios of macropores obtained by the two methods are quantitatively quite different. The discrepancy is mainly caused by the different test principles adopted by the two methods.

In this paper, a new magnetic polymer–supported phosphate adsorbent MPVC-EDA-Ce was prepared by loading cerium (hydr)oxides onto ethylenediamine-functionalized polyvinyl chloride for the first time. MPVC-EDA-Ce showed excellent adsorption performances towards phosphate and easy recovery. The adsorption isotherm and kinetics of MPVC-EDA-Ce followed Langmuir monolayer model and the pseudo-second-order model, respectively. The pH results demonstrated that the MPVC-EDA-Ce could effectively remove phosphate in a wide range of pH with insignificant cerium leaching. Furthermore, analyses on adsorption mechanism and effect of competing anions demonstrated the formation of strong inner-sphere complexation between cerium (hydr)oxides and phosphate, which was a selective adsorption process, while positively charged quaternary ammonium groups adsorbed phosphate via relatively weak electrostatic attraction which was a non-selective adsorption process. The study provided a good reference to design novel phosphate adsorbents with two even more functional adsorption sites and a deep insight to investigate the adsorption mechanism towards phosphate.