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Organic carbon concentration profiles in recent cave sediments: records of agricultural pollution or diagenesis?.
1996
Bottrell S.H.
Ozone alters carbon allocation in loblolly pine: assessment with carbon-11 labeling.
1990
Spence R.D. | Rykiel E.J. Jr. | Sharpe P.J.H.
The carbon budget of Canadian forests: A sensitivity analysis of changes in disturbance regimes, growth rates, and decomposition rates.
1994
Kurz W.A. | Apps M.J.
Uptake of terbuthylazine and its medium polar metabolites into maize plants.
1995
Gayler S. | Trapp S. | Matthies M. | Schroll R. | Behrendt H.
Carbonaceous aerosol at urban and rural sites in the United States.
1986
Shah J.J. | Johnson R.L. | Heyerdahl E.K. | Huntzicker J.J.
Dissolved organic carbon in the unsaturated zone under land irrigated by wastewater effluent.
1990
Amiel A.J. | Magaritz M. | Ronen D. | Lindstrand O.
Blood mercury concentrations in four sympatric gull species from South Western France: Insights from stable isotopes and biologging
2022
Jouanneau, William | Sebastiano, Manrico | Rozen-Rechels, David | Harris, Stephanie M. | Blévin, Pierre | Angelier, Frédéric | Brischoux, François | Gernigon, Julien | Lemesle, Jean-Christophe | Robin, Frédéric | Cherel, Yves | Bustamante, Paco | Chastel, Olivier
Mercury (Hg) is a toxic trace element widely distributed in the environment, which particularly accumulates in top predators, including seabirds. Among seabirds, large gulls (Larus sp) are generalist feeders, foraging in both terrestrial and marine habitats, making them relevant bioindicators of local coastal Hg contamination. In the present study, we reported blood Hg concentrations in adults and chicks of four different gull species breeding on the French Atlantic coast: the European herring gull (Larus argentatus), the Lesser black-backed gull (L. fuscus), the Great black-backed gull (L. marinus) and the Yellow-legged gull (L. michahellis). We also investigated the potential role of foraging ecology in shaping Hg contamination across species, using the unique combination of three dietary tracers (carbon, nitrogen and sulfur stable isotopes) and biologging (GPS tracking). A high concentration of Hg was associated with high trophic position and a marine diet in gulls, which was corroborated by birds’ space use strategy during foraging trips. Adults of all four species reached Hg concentrations above reported toxicity thresholds. Specifically, adults of Great black-backed gulls had a high trophic marine specialized diet and significantly higher Hg concentrations than the three other species. Blood Hg was 4–7 times higher in adults than in chicks, although chicks of all species received mainly marine and high trophic position prey, which is expected to be the cause of blood Hg concentrations of toxic concern. By using both stable isotopes and GPS tracking, the present study provides compelling insights on the main feeding habits driving Hg contamination in a seabird assemblage feeding in complex coastal environments.
Показать больше [+] Меньше [-]Inhalation bioaccessibility of multi-class organic pollutants associated to atmospheric PM2.5: Correlation with PM2.5 properties and health risk assessment
2022
Sánchez-Piñero, Joel | Novo-Quiza, Natalia | Pernas-Castaño, Cristina | Moreda-Piñeiro, Jorge | Muniategui-Lorenzo, Soledad | López-Mahía, Purificación
Inhalation exposure to fine particulate matter (PM₂.₅) represents a global concern due to the adverse effects in human health. In the last years, scientific community has been adopted the assessment of the PM₂.₅-bound pollutant fraction that could be released (bioaccessible fraction) in simulated lung fluids (SLFs) to achieve a better understanding of PM risk assessment and toxicological studies. Thus, bioaccessibility of 49 organic pollutants, including 18 polycyclic aromatic hydrocarbons (PAHs), 12 phthalate esters (PAEs), 11 organophosphorus flame retardants (OPFRs), 6 synthetic musk compounds (SMCs) and 2 bisphenols in PM₂.₅ samples was evaluated. The proposed method consists of a physiologically based extraction test (PBET) by using artificial lysosomal fluid (ALF) to obtain bioaccessible fractions, followed by a vortex-assisted liquid-liquid microextraction (VALLME) and a final analysis by programmed temperature vaporization-gas chromatography-tandem mass spectrometry (PTV-GC-MS/MS). The highest inhalation bioaccessibility ratio was found for bisphenol A (BPA) with an average of 83%, followed by OPFRs, PAEs and PAHs (with average bioaccessibilities of 68%, 41% and 34%, respectively). Correlations between PM₂.₅ composition (major ions, trace metals, equivalent black carbon (eBC) and UV-absorbing particulate matter (UVPM)) and bioaccessibility ratios were also assessed. Principal Component Analysis (PCA) suggested that PAHs, PAES and OPFRs bioaccessibility ratios could be positively correlated with PM₂.₅ carbonaceous content. Furthermore, both inverse and positive correlations on PAHs, PAEs and OPFRs bioaccessibilites could be accounted for some major ions and metal (oid)s associated to PM₂.₅, whereas no correlations comprising considered PM₂.₅ major ions and metal (oid)s contents and BPA bioaccessibility was observed. In addition, health risk assessment of target PM₂.₅-associated PAHs via inhalation was assessed in the study area considering both total and bioaccessible concentrations, being averaged human health risks within the safe carcinogenic and non-carcinogenic levels.
Показать больше [+] Меньше [-]Nano agrochemical zinc oxide influences microbial activity, carbon, and nitrogen cycling of applied manures in the soil-plant system
2022
Shah, Ghulam Mustafa | Ali, Hifsa | Ahmad, Iftikhar | Kāmrān, Muḥammad | Hammad, Mohkum | Shah, Ghulam Abbas | Bakhat, Hafiz Faiq | Waqar, Atika | Guo, Jianbin | Dong, Renjie | Rashid, Muhammad Imtiaz
The widespread use of nano-enabled agrochemicals in agriculture for remediating soil and improving nutrient use efficiency of organic and chemical fertilizers is increasing continuously with limited understanding on their potential risks. Recent studies suggested that nanoparticles (NPs) are harmful to soil organisms and their stimulated nutrient cycling in agriculture. However, their toxic effects under natural input farming systems are just at its infancy. Here, we aimed to examine the harmful effects of nano-agrochemical zinc oxide (ZnONPs) to poultry (PM) and farmyard manure (FYM) C and N cycling in soil-plant systems. These manures enhanced microbial counts, CO₂ emission, N mineralization, spinach yield and N recovery than control (unfertilized). Soil applied ZnONPs increased labile Zn in microbial biomass, conferring its consumption and thereby reduced the colony-forming bacterial and fungal units. Such effects resulted in decreasing CO₂ emitted from PM and FYM by 39 and 43%, respectively. Further, mineralization of organic N was reduced from FYM by 32%, and PM by 26%. This process has considerably decreased the soil mineral N content from both manure types and thereby spinach yield and plant N recoveries. In the ZnONPs amended soil, only about 23% of the applied total N from FYM and 31% from PM was ended up in plants, whereas the respective fractions in the absence of ZnONPs were 33 and 53%. Hence, toxicity of ZnONPs should be taken into account when recommending its use in agriculture for enhancing nutrient utilization efficiency of fertilizers or soil remediation purposes.
Показать больше [+] Меньше [-]Evaluating the influence of constant source profile presumption on PMF analysis of PM2.5 by comparing long- and short-term hourly observation-based modeling
2022
Xie, Mingjie | Lu, Xinyu | Ding, Feng | Cui, Wangnan | Zhang, Yuanyuan | Feng, Wei
Hourly PM₂.₅ speciation data have been widely used as an input of positive matrix factorization (PMF) model to apportion PM₂.₅ components to specific source-related factors. However, the influence of constant source profile presumption during the observation period is less investigated. In the current work, hourly concentrations of PM₂.₅ water-soluble inorganic ions, bulk organic and elemental carbon, and elements were obtained at an urban site in Nanjing, China from 2017 to 2020. PMF analysis based on observation data during specific pollution (firework combustion, sandstorm, and winter haze) and emission-reduction (COVID-19 pandemic) periods was compared with that using the whole 4-year data set (PMFwₕₒₗₑ). Due to the lack of data variability, event-based PMF solutions did not separate secondary sulfate and nitrate. But they showed better performance in simulating average concentrations and temporal variations of input species, particularly for primary source markers, than the PMFwₕₒₗₑ solution. After removing event data, PMF modeling was conducted for individual months (PMFₘₒₙₜₕ) and the 4-year period (PMF₄₋yₑₐᵣ), respectively. PMFₘₒₙₜₕ solutions reflected varied source profiles and contributions and reproduced monthly variations of input species better than the PMF₄₋yₑₐᵣ solution, but failed to capture seasonal patterns of secondary salts. Additionally, four winter pollution days were selected for hour-by-hour PMF simulations, and three sample sizes (500, 1000, and 2000) were tested using a moving window method. The results showed that using short-term observation data performed better in reflecting immediate changes in primary sources, which will benefit future air quality control when primary PM emissions begin to increase.
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