Environments, Volume 6, Issue 4 (April 2019) – 9 articles

Noise pollution coming from traffic noise has become an important issue in urban areas. Road noise is one of the main sources of high-level traffic noise. Road noise depends not only on tires but on the pavement. Therefore, a study of mixture parameters should be performed to achieve good acoustic performance. Another important point which has to be taken into account is the acoustic performance durability. Gap-graded mixtures were selected for this project due to poor experiences with open-graded mixtures in terms of performance durability, where texture and clogging issues appeared a few years after paving. The LIFE SOUNDLESS project is seeking different ways to modify stone mastic asphalt mixes to improve the noise attenuation of pavements. A selection of mixes with different additives were created, where some waste materials were used. The selection of the best mixtures was done not only according to traditional mechanical parameters but also others, such as damping and dynamic stiffness. Once the best mixtures had been paved, the acoustic performances were measured several times to evaluate the performance durability. Several experimental methods like the close proximity (CPX) method and statistical pass by (SPB) method were used to check the sound generation and propagation of every pavement. The project was carried out on two roads overseen by the Junta de Andalucía in Seville (Spain). The difference between both roads was the traffic density and the average speed. The noise level has since been reduced by 3 dB and 7 dB on both sites. Full article

The increased energy demand and related environmental problems caused by burning fossil fuels have raised interest in alternative energy sources. This study investigated the wind characteristics and available wind energy for three urban regions in Northern Cyprus using the Weibull distribution function. The results illustrate that Gazimağusa is the most applicable location for harvesting the kinetic energy of the wind compared to Lefkoşa and Girne. Moreover, the solar potential at a specific location can be analyzed using a different simulation tool. In the present paper, the performance of a rooftop Photovoltaic (PV) system for household buildings in three selected is assessed. Three types of simulation software (PVGIS, PV*SOL, and PVWatts) are used to evaluate the performance of the 6.4 kWp grid-connected rooftop PV system. This study assessed the energy generation, performance ratio and capacity factor for this PV system. The results concluded that PVGIS is an easy, fast, and reliable software tool that can be used for the simulation of a solar PV system in the studied regions. Furthermore, an economic evaluation of renewable systems in the three urban regions is presented. As a result, a small-scale grid-connected solar/wind system that is able to generate electricity with an excellent percentage of clean energy was proposed and developed. The analysis indicates that the proposed PV projects showed significant potential in the studied locations. In addition, the proposed PV system is the most economical option for generating electricity compared to wind systems due to the low electricity prices and of the ability to recover the initial investment. Consequently, it is expected that the simulation results will help in demonstrating the advantages and challenges of installing grid-connected PV systems for households in Northern Cyprus in order to reduce the electricity consumption produced by fossil fuels. Full article

Ozone (O₃) pollution has become one of the most challenging problems in China, and high O₃ concentrations have been a major air quality issue in Changchun. Based on continuous observation data of surface ozone concentrations from ten automatic air monitoring stations and meteorological data from the meteorological bureau in Changchun, the temporal and spatial variations of the O₃ concentration and its relationships with meteorological factors were analyzed by correlation analysis during the period of 2013–2017. The results showed the following: A single apex model of the annual mean O₃ concentrations of the daily maximum 8 h average (MDA8) was found from the data for 2013 to 2017 in Changchun, with the highest MDA8 O₃ concentrations in 2015 and a slight decline from then until 2017. The O₃ concentrations in the suburban areas and the south of Changchun were higher than those downtown and north of the city. The seasonal variation of O₃ concentrations was obvious, following the order summer > spring > autumn > winter, which was similar to the results of neighboring cities and provinces in Changchun. The days on which O₃ concentrations exceeded the standard were concentrated in summer and spring, and the total number of ozone excess days was 91 days; the maximum number of ozone excess days was in 2015. The O₃ concentration exceeded the standard in Changchun mainly in March–August, and its monthly mean value curve showed a bimodal type in which the highest values appeared in May and July, while the lowest values appeared in December. The diurnal pattern of ozone showed a single peak mode, and the peak value usually appeared at 14:00–16:00 while the minimum value appeared at 07:00–08:00. O₃ concentrations in Changchun and the six selected pollutants CO, NO, NO₂, NOx, PM₁₀, and PM_2.5 were negatively correlated. Higher temperature is a necessary synoptic condition for ozone pollution in Changchun: when the temperature rose, O₃ concentrations increased significantly; further, O₃ concentrations were negatively correlated with relative humidity and atmospheric pressure and were positively correlated with temperature and solar radiation. The O₃ concentrations were highest when the wind scale approached 14~20 km/h and the wind direction was S. Combined with the research results in the surrounding areas of Changchun, it is indicated that there may be an ozone contribution from south of Changchun through long-range pollution transport and tropospheric subsidence. Full article

About half of the energy loss in buildings is wasted through windows. Determining the optimum window-to-wall ratio (WWR) for different building facades would reduce such energy losses. The optimum WWR is the window area that minimizes the total annual energy of cooling, heating, and lighting. The purpose of this study is to investigate the optimum WWR of different facades of an office building. For this purpose, a sample building is simulated by means of DesignBuilder software in order to investigate the annual solar heat gain, cooling load, heating load, and lighting consumption for the three cities of Bushehr, Shiraz, and Tabriz, and optimum window areas of office buildings for the three cities are determined. Based on the results, the optimum window area for the north building facade for all climates is 20–30%. This amount for the southern facade of the building in Bushehr, Shiraz, and Tabriz is, respectively, 20–30%, 10–30%, and 20–50%. The optimum window area for the eastern and western building facades in Bushehr is 30–50%; in Tabriz it is 40–70%, and in Shiraz it is 20–60% and 40–70%, respectively. The difference between the maximum and minimum energy consumption with different window areas in Bushehr and Shiraz is 20–100% and in Tabriz it is 16–25%. Full article

Digestion of wastes to produce biogas is complicated by poor degradation of feedstocks. Research has shown that waste digestion can be enhanced by the addition of low levels of aeration without harming the microbes responsible for methane production. This research has been done at small scales and without provision to retain the aeration in the digestate. In this paper, low levels of aeration were provided to poultry litter slurry through a sub-surface manifold that retained air in the sludge. Digestate (133 L) was supplied 0, 200, 800, or 2000 mL/day air in 200 mL increments throughout the day via a manifold with a volume of 380 mL. Digesters were fed 400 g of poultry litter once weekly until day 84 and then 600 g thereafter. Aeration at 200 and 800 mL/day increased biogas production by 14 and 73% compared to anaerobic digestion while aeration at 2000 mL/day decreased biogas production by 19%. Biogas quality was similar in all digesters albeit carbon dioxide and methane were lowest in the 2000 mL/day treatment. Increasing feed to 600 g/week decreased gas production without affecting biogas quality. Degradation of wood disks placed within the digesters was enhanced by aeration. Full article

Parks and protected areas are recognized for the important ecosystem services, or benefits, they provide society. One emerging but understudied component is the cultural ecosystem services that parks and protected areas provide. These cultural ecosystem services include a variety of benefits, such as cultural heritage, spiritual value, recreation opportunities, and human health and well-being. However, many of these services can only be provided if people visit these parks and protected areas through tourism opportunities. However, with this tourism use comes a variety of inevitable resource impacts. This current research connects potential impacts from tourism in parks and protected areas to the health and well-being aspect of cultural ecosystem services. We used an MTurk sample to record affective responses across a range of resource conditions. Results demonstrate that as tourism-related ecological impacts increased, positive affect decreased. Decreases in positive affect were more severe for park and protected area scenes featuring informal and/or undesignated social trails when compared to scenes with increasing levels of trampling/vegetation loss. Collectively, the results show that managing tourism in parks and protected areas in a manner that reduces impact is essential to providing beneficial cultural ecosystem services related to human health and well-being. Full article

PM_2.5 pollution is of great concern in China due to its adverse health effects. Many diseases have been proven to be associated with PM_2.5 components, but the effects of chemical characteristics of PM_2.5 on toxicological properties, especially in different human organs, are poorly understood. In this study, two seasonal PM_2.5 samples (summer and winter) were collected in Nanjing, and their chemical compositions (heavy metals, water-soluble ions, organic carbon (OC), and elemental carbon (EC)) were analyzed. Human lung epithelial carcinoma cells (A549), human hepatocellular liver carcinoma cells (HepG₂), and human neuroblastoma cells (Sh-Sy5y) were employed to evaluate the toxicological properties of the collected PM_2.5. The results showed that the average mass concentrations of PM_2.5 were lower in summer (51.3 ± 21.4 μg/m³) than those in winter (62.1 ± 21.5 μg/m³). However, the mass fractions of heavy metals, OC, and EC exhibited an opposite seasonal difference. Among all tested fractions, water-soluble ions were the major compositions of particles in both summer and winter, especially the secondary ions (SO₄²⁻, NO₃⁻ and NH₄⁺). Besides, the ratio of OC/EC in PM_2.5 was greater than two, indicating serious secondary pollution in this area. The NO₃^–/SO₄²⁻ ratio (< 1) suggested that fixed sources made important contributions. The toxicological results showed that PM_2.5 in the summer and winter significantly inhibited cell viability (p < 0.01) and induced intracellular reactive oxygen species (ROS) production (p < 0.01). Moreover, the viability inhibition in A549, Sh-Sy5y, and HepG₂ cells was more prominent in summer, especially at high PM_2.5 (400 μg/mL) (p < 0.05), and the induction of reactive oxygen species (ROS) in A549 and Sh-Sy5y cells was also more evident in summer. Such seasonal differences might be related to the variations of PM_2.5 components. Full article

Due to the particular characteristics of hospitals, these buildings are highly sensitive to environmental noise. However, they are usually located close or within urban agglomerations. Hence, hospitals are, in many cases, exposed to high levels of environmental noise. A study of one of the main hospitals in the Extremadura region (Spain) is presented here to allow a global assessment of the acoustic impact of outdoor sound sources. Both long- and short-term measurements were carried out, and a software model was developed. The measured values exceed the World Health Organisation reference value of 50 dBA for daytime and evening, and are even higher than the 55 dBA limit at which severe annoyance is generated. Taking into account the results obtained, the noise impact on this hospital is primarily influenced by three sound sources: road traffic, cooling towers of the hospital and the emergency helicopter. Their relative importance depends on the facade under consideration. It can therefore be concluded that the overall situation of the hospital needs to be improved. Thus, a series of solutions are proposed for a possible action plan based on interventions regarding the main sound sources and the location of the most sensitive areas to environmental noise. Full article

New solar energy facilities on public lands in the deserts of southern California are being monitored long-term to detect environmental impacts. For this purpose, we have developed a framework for detecting changes in vegetation cover region-wide using greenness index data sets from the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensor. This study focused on three sites, Joshua Tree National Park (JOTR), Mojave National Preserve (MOJA), and a proximal group of solar energy Development Focus Areas (DFAs). Three MODIS vegetation indices (VIs), the normalized difference (NDVI), enhanced (EVI), and soil-adjusted (SAVI), all at 250-m spatial resolution, were evaluated using the Breaks for Additive Season and Trend (BFAST) methodology to estimate significant time series shifts (“breakpoints”) in green vegetation cover, from February 2000 to May 2018. The sample cross-correlation function with local precipitation records and comparison with timing of wildfires near the study sites for breakpoint density (proportion of area with a breakpoint) showed that NDVI had the strongest response and hence greatest sensitivity to these major disturbances compared to EVI and SAVI, supporting its use over the other VIs for subsequent analysis. Time series of NDVI breakpoint change densities for individual solar energy DFAs did not have a consistent vegetation response following construction. Bootstrap-derived 95% confidence intervals show that the DFAs have significantly larger kurtosis and standard deviation in positive NDVI breakpoint distribution than protected National Park System (NPS) sites, but no significant difference appeared in the negative distribution among all sites. The inconsistent postconstruction NDVI signal and the large number of detected breakpoints across all three sites suggested that the largest shifts in greenness are tied to seasonal and total annual precipitation amounts. Further results indicated that existing site-specific conditions are the main control on vegetation response, mostly driven by the history of human disturbances in DFAs. Although the results do not support persistent breakpoints in solar energy DFAs, future work should seek to establish links between statistical significance and physical significance through ground-based studies to provide a more robust interpretation. Full article