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Differences in isoprene and monoterpene emissions from cold-tolerant eucalypt species grown in the UK
2020
Purser, Gemma | Heal, Mathew R. | White, Stella | Morison, James I.L. | Drewer, Julia
The UK may be required to expand its bioenergy production in order to make a significant contribution towards the delivery of its ‘net zero’ greenhouse gas emissions target by 2050. However, some trees grown for bioenergy are emitters of volatile organic compounds (VOCs), including isoprene and terpenes, precursors in the formation of tropospheric ozone, an atmospheric pollutant, which require assessment to understand any consequent impacts on air quality. In this initial scoping study, VOC emission rates were quantified under UK climate conditions for the first time from four species of eucalypts suitable for growing as short-rotation forest for bioenergy. An additional previously characterised eucalypt species was included for comparison. Measurements were undertaken using a dynamic chamber sampling system on 2-3 year-old trees grown under ambient conditions. Average emission rates for isoprene, normalised to 30 °C and 1000 μmol m⁻² s⁻¹ PAR, ranged between 1.3 μg C gdw⁻¹ h⁻¹ to 10 μg C gdw⁻¹ h⁻¹. All the eucalypt species measured were categorised as ‘medium’ isoprene emitters (1–10 μg C gdw⁻¹ h⁻¹). Total normalised monoterpene emission rates were of similar order of magnitude to isoprene or approximately one order of magnitude lower. The composition of the monoterpene emissions differed between the species and major compounds included eucalyptol, α-pinene, limonene and β-cis-ocimene. The emission rates presented here contribute the first data for further studies to quantify the potential impact on UK atmospheric composition, if there were widespread planting of eucalypts in the UK for bioenergy purposes.
Show more [+] Less [-]Seasonal effects of atmospheric particulate matter on performance of different types of photovoltaic modules in sanliurfa, Turkey
2020
Dogan, Tuba Rastgeldi | Beşli, Nurettin | Aktacir, Mehmet Azmi | Dinç, Merve Nur | İlkhan, Mehmet Akif | Öztürk, Fatma | Yıldız, Melek
In Turkey, Southeastern Anatolia region is the highest in terms of solar radiation level. However, the provinces in the region are subject to Particulate Matter (PM) coming from the Sahara desert, the Syrian Desert and the Arabian Desert by atmospheric transport. The daily limit of PM₁₀ and PM₂.₅ set by WHO for health is often exceeded in Sanliurfa. PM₁₀ and PM₂.₅ pollutants also accumulate on the Photovoltaic (PV) panels and cause loss of PV panel performance. In this study, the effects of atmospheric dust deposition on the performance of PV panel was determined for both monocrystalline and polycrystalline technologies under Sanliurfa atmospheric conditions. Two panels with the same characteristics were used for each PV panel group from 2 different PV technologies. One of the panels in the group was cleaned by washing with distilled water every Monday while the other was not cleaned. Thus, the effect of the dust accumulation on the PV panel was determined by comparison to the cleaned PV panel. PV panel power is measured with I–V meter. Panel surface temperature, solar radiation and other meteorological parameters are measured simultaneously. The measurements were done every Monday, Wednesday and Friday at 12:00 am from May 1 to December 31, 2019. It is observed that the dust accumulation reduces the PV power output up to 8% depending on the amount of radiation. During the summer months, the power loss on the average is 4.33% for monocrystalline and 4.57% for polycrystalline. In the autumn months, it is less than 1.77%.
Show more [+] Less [-]Contents, distribution and sources of lanthanoid elements in rural and urban atmospheric particles in Cienfuegos (Cuba)
2020
Morera-Gómez, Yasser | Alonso-Hernández, Carlos Manuel | Widory, David | Lasheras, Esther | Santamaría, Jesús Miguel | Elustondo, David
This study investigates the contents, distribution patterns, and sources of lanthanoid elements (La to Lu) in aerosols with an aerodynamic diameter ≤10 μm (PM₁₀) in a coastal Caribbean region in order to better constrain the origin of the atmospheric PM contamination. We sampled and analysed PM₁₀ aerosols during 2015 simultaneously at a rural and an urban site in Cienfuegos (Cuba) as well as particles samples from regional contamination sources. Results showed that the sum of the studied lanthanoids concentrations ranged from 0.03 to 13.42 ng m⁻³ and from 0.51 to 18.75 ng m⁻³ at the rural and the urban site, respectively. Time variations for the lanthanoid concentrations displayed similar trends and showed that the highest concentrations corresponded to the influence of the African dust for both sites, but presented distinct variability and lower concentrations when dust intrusions were less frequent. The lanthanoid distribution patterns in the rural and urban sites were significantly different, due to the impact of different local combustion sources. Our results were comforted by comparing the degree of fractionation of the lighter and heavier lanthanoids and the δEu and δCe anomalies between our PM₁₀ samples and those of the local sources of contamination. Ultimately, we highlight the added value of lanthanoid elements as reliable indicators for discriminating emission sources and for tracking the origin of atmospheric particulate matter.
Show more [+] Less [-]Ionic composition of PM2.5 particle fraction at a coastal urban background site in Croatia
2020
Gluščić, Valentina | Čačković, Mirjana | Pehnec, Gordana | Bešlić, Ivan
The mass concentrations and content of water-soluble anions (Cl⁻, NO₃⁻, SO₄²⁻) and cations (Na⁺, NH₄⁺, K⁺, Mg²⁺, Ca²⁺) in the PM₂.₅ particle fraction were measured, and an investigation of their relationship and their contribution to the total PM₂.₅ mass measured was conducted at an urban background site as part of the Croatian monitoring network for air quality located in Rijeka, Croatia. Daily samples of PM₂.₅ particle fraction were collected over 2017 on PTFE filters using a low volume sampler Sven Leckel SEQ 47/50. Mass concentrations of the PM₂.₅ particle fraction were determined by gravimetry according to the standard HRN EN 12341:2014 (EN 12341:2014). The content of water-soluble inorganic anions and cations were determined using a Thermo Scientific ICS-5000 capillary ion chromatograph. Results show that the annual average PM₂.₅ mass concentration was 9.65 μg m⁻³ and did not exceed the limit value of 25 μg m⁻³ given by the Regulation on the level of pollutants in air (OG No. 117/12). The annual average mass concentrations of ions in PM₂.₅ particle fraction was SO₄²⁻> NH₄⁺> NO₃⁻ > Ca²⁺> K⁺> Na⁺> Cl⁻ > Mg²⁺. The contributions of total anion mass and total cation mass to the total PM₂.₅ mass were 25.4% and 12.8%, respectively. The acidic property of PM₂.₅ was obtained in spring and winter and slightly acidic in summer and autumn. For a prediction of the pollutant sources, we ran a factor analysis which was performed using the statistical packages STATISTICA 13.0. After varimax rotation, the obtained four principal component factors were found to account for 86% of the variance. Factor loadings > 0.7 were considered significant.
Show more [+] Less [-]Evaluation of hourly-based precipitation chemistry in suburban site of Bolu
2020
Karadeniz, Hatice | Yenisoy-Karakaş, Serpil
Precipitation chemistry is important for understanding atmospheric chemistry and transportation mechanism for a region. Therefore, 6-h rain samples were collected manually on the Black Sea Region of Turkey between March 2019 and May 2019. Totally, 21 wet deposition samples were collected in 12 rainy days. The collected rain samples were analyzed by ion chromatography for ions, including Cl⁻, NO₂⁻, NO₃⁻, SO₄²⁻, Na⁺, Ca²⁺, Mg²⁺, K⁺, NH₄⁺. Volume weighted mean (VWM) concentrations of ions were calculated and were in the order of Na⁺ > Ca²⁺ > Cl⁻ > SO₄²⁻ > NO₃⁻ > Mg²⁺ > K⁺ > NH₄⁺> NO₂⁻. The pH values of individual precipitation varied from 4.70 to 8.07. Anion to cation ratio was 0.74 ± 0.34 thus it was an indication of anion deficiency. A strong correlation between NH₄⁺ and SO₄²⁻, NH₄⁺ and NO₃⁻, Ca²⁺ and SO₄²⁻, Ca²⁺, and NO₃⁻ was found in the samples due to the neutralization process. The back trajectory model was used to find the long-range sources and the influence of air masses coming from Saharan, Europe, and the Black Sea. Calcium ion was found to be an effective ion in the neutralization processes by analysis of multiple linear regression and neutralization factor calculation. Approximately 79.5% of SO₄²⁻ and 59.7% of NO₃⁻ were neutralized by Ca²⁺ and NH₄⁺. The washout mechanism for Na⁺, Mg²⁺, Ca²⁺, and K⁺ was dominantly observed on the March 12, 2019. Rainout mechanism was seen on the April 13, 2019 rain event due to the long-range transportation from Saharan Dust.
Show more [+] Less [-]Mass concentrations and lung cancer risk assessment of PAHs bound to PM1 aerosol in six industrial, urban and rural areas in the Czech Republic, Central Europe
2020
Křůmal, Kamil | Mikuška, Pavel
The daily concentrations of 15 polycyclic aromatic hydrocarbons (PAHs) in PM₁ aerosol samples, including 7 carcinogenic PAHs, were determined in six urban/rural areas in the Czech Republic in winter seasons between 2013 and 2017. The PM₁ aerosol was collected on quartz fibre filters using high-volume samplers for 24 h and PAHs were analysed by GC-MS. The highest concentrations of PAHs were found in the industrial city Ostrava (60.8 ng m⁻³), which is one of the most polluted areas in the Czech Republic, while the lowest concentrations were obtained in the small town Čelákovice (11.7 ng m⁻³) and in the background rural area Košetice (12.3 ng m⁻³). Carcinogenic PAHs formed 43.9%–57.8% of total analysed PAHs.The toxic equivalence factors for individual PAHs adopted from literature and two unit risks (Cal-EPA and WHO) were used for the evaluation of carcinogenic risk of PAHs exposure. The inhalation cancer risk models assume a lifetime exposure (70 years), whereas our measurement was realized for a relatively short duration in winters where concentrations of PAHs are usually high. The average of PAHs concentrations will be lower for the whole year resulting in lower lung cancer risk values. The calculated lifetime lung cancer risk of PAHs exposure for the measured winter periods suggested 1545 cases per 1 million people in Ostrava (industrial area), 192–456 cases per 1 million people in other four investigated cities/towns and 182 cases per 1 million people in Košetice (rural area). The calculated lifetime lung cancer risk values are related only to ambient concentrations of PAHs in atmospheric aerosols. Nevertheless, other factors can influence and increase the lung cancer risk, e.g., occupation, smoking, indoor emissions of coal/wood combustion in stoves or genetic factors of individuals. Our results can also be underestimated due to the determination of PAHs only in PM₁ aerosol.
Show more [+] Less [-]Recycled moisture in an enclosed basin, Guanzhong Basin of Northern China, in the summer: Contribution to precipitation based on a stable isotope approach
2020
Li, Xiaofei | Lu, Aigang | Feng, Qi | Li, Zhi | Liu, Weiguo | Wang, Shengjie | Tripathee, Lekhendra | Wang, Xiaoyan | Cao, Junji
Recycled moisture, mainly originated from evapotranspiration (surface evaporation and transpiration), is the main sources of precipitation. Influenced on the different regional/local environments, the contributions of recycled moisture to precipitation present as different proportions. Recycled moisture has an important impact on the hydrological cycle, further occurred a series of environmental effect for regional/local. Aimed to estimate the contribution of recycled moisture to precipitation in an enclosed basin, Guanzhong Basin of northern China, precipitation and lake/reservoir samples were collected. The isotope ratio analysis was done for the summer season, and a three-component mixing model based on the stable hydrogen and oxygen isotopes was applied. The results indicated that the averaged contribution of recycled moisture to precipitation was 17.44% in Guanzhong Basin of northern China, while the mean proportions of surface evaporation moisture and transpiration moisture were found to be 0.38% and 16.97%, respectively. Comparatively, most of the recycled moisture mainly comes from transpiration moisture rather than evaporation moisture, suggesting that transpiration moisture from cropland, vegetation, and plants instead of evaporation is dominant in moisture recycling of the Guanzhong Basin.
Show more [+] Less [-]Exposure to the herbicide 2,4-dichlorophenoxyacetic acid impairs mitochondrial function, oxidative status, and behavior in adult zebrafish
2020
Thiel, Nathana Andressa | Sachett, Adrieli | Schneider, Sabrina Ester | Garbinato, Cristiane | Decui, Laura | Eichwald, Tuany | Conterato, Greicy M. M. | Latini, Alexandra | Piato, Angelo | Siebel, Anna Maria
2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most commonly used herbicides worldwide. While the effects of 2,4-D in target organisms are well known, its consequences in nontarget organisms are not fully explained. Therefore, the purpose of this study was to investigate the effects of the herbicide on mitochondrial energy metabolism, oxidative status, and exploratory behavior in adult zebrafish. Animal exposure to 2,4-D increased cytochrome c oxidase and catalase activities and reduced SOD/CAT ratio, moreover, increased the total distance traveled and the number of crossings. Finally, animals exposed to 2,4-D spent more time in the upper zone of the tank and traveled a long distance in the upper zone. Overall, our results indicate the 2,4-D can provoke disabling effects in nontarget organisms. The obtained data showed that exposure to 2,4-D at environmentally relevant concentrations alters mitochondrial metabolism and antioxidant status and disturbs the zebrafish innate behavior.
Show more [+] Less [-]Biosurfactant electrospun nanofibers exhibit minimal side effects on the structure and function of the liver tissue in male rat model
2020
Ebaid, Hossam Abd Rabou | Abdel-Mageed, Ahmed | Al-Tamimi, Jameel Homoud | Hassan, Iftekhar | Rady, Ahmed Mostafa | El-Newehy, Mohamed Hassan | Mashaly, Ashraf Mohamed | Abdel-Megeed, Ahmed AbdelFattah Mahmoud | Alhazza, Ibrahim | Abdel-Halim, Essam Sayed | Salem, Abdelfattah Zeidan Mohamed
Oil spills can result in significant damage to marine estuaries, rivers, lakes, wetlands, and shorelines. Electrospun nanofibers containing biosurfactant (ENFs) can be used to clean oil spills up and protect the environmental biology. Present work aimed to study the side-effects of prepared nanofibers on animal models. Screening of the prepared ECNFs on animals showed that three of them (PVA-5, PEO-1, and PEO-5) are safe to hepatic tissues and liver functions. Furthermore, oxidative stress did not change after using these nanofibers. The PVA-1 nanofibers, however, were found to cause major pathological changes in the liver tissue. In addition, PVA-1 nanofibers were proved to alter the total white blood count and the neutrophil percentages significantly in comparison to the control. In conclusion, PVA-5, PEO-1, and PEO-5 are safe to hepatic tissues and liver functions.
Show more [+] Less [-]Analysis of the interannual variation characteristics of the northernmost drift position of the green tide in the Yellow Sea
2020
Li, Dongxue | Gao, Zhiqiang | Zheng, Xiangyang | Wang, Nanyu
The green tide in the Yellow Sea is the world’s largest macroalgal bloom. The maximum area affected by green tide can reach tens of thousands of square kilometers. Previous studies have shown that green tide drifts northward during the outbreak, yet the location of its northernmost drift and the characteristics of interannual variations have not been explored in detail. In this paper, we use the Moderate Resolution Imaging Spectrometer (MODIS) data, GaoFen-1 (GF-1) satellite data, unmanned aerial vehicle (UAV) aerial data, and field trips for extraction and monitoring of green tide and then analyze the emergence, development, and dissipation of the green tide in Rongcheng coastal waters and the change of the northernmost drift position and its related factors from the year of 2013 to 2018. The results show that green tide have drifted to the Rongcheng coastal area over the years and the northernmost drift position can reach 37.662° N in 2014. Interannual difference of the northernmost position of the drift of the green tide is obvious, it is mainly affected by the wind, and there is no certain connection with the maximum coverage area, the coverage area when reaching the northernmost position, and the existence days of the green tide. These results can help to understand the drift range and dissipation process of green tide in the Yellow Sea.
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