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[en] During recent field surveys, a new Ceylon iron wood (Manilkara hexandra) population was discovered in the Upper Ganga Ramsar Site, Uttar Pradesh (UP), India. The largest specimen located at Van Khan-deshwar partially collapsed in 2012, which led to a canopy impairment. The rupture enabled direct extraction of samples close to the pith of the main stem. The radiocarbon date of the oldest sample was 361 ± 23 BP, which corresponds to a calibrated age of 525 ± 25 cal yr. The results indicate the Ceylon iron wood of Narora, UP is the oldest dated extant M. hex-andra with a calculated age of 550 ± 50 yr. Several protection measures are presented and urgent action is required to prevent the total collapse of this ancient tree. (author)
[en] In this study, radon (222Rn) measurements were taken at compacted uranium tailings with cover materials by a self-developed coupling testing system under different low-frequency vibration loads and gas seepage rates. The maximum measured value appears at 0.723 Bq m-2 s-1, which is close to the upper limit value of national standard of China (0.74 Bq m-2 s-1). A vibration load significantly damages the compacted uranium tailings sample structure, resulting in a marked increase in the porosity of the porous media thus forming a channel for radon migration. The results presented here may provide a workable approach for simulating geological dynamic load conditions for radon exhalation studies on uranium tailings impoundment. (author)
[en] Non-Aqueous Phase Liquids (NAPLs) compounds are complex mixtures of organic liquids derived from petroleum or other industrial activities. Contamination of soils and groundwater by NAPLs can generate health and economic problems by compromising water resources, restrict soil use, and cause damage to the public and private patrimony and the environment. In the last decades, there has been an increase in areas contaminated by different types of NAPLs, a cause of great concern worldwide, mainly due to the difficulty of locating and quantifying contamination. These issues are majors obstacles that prevent the cleaning of soils and groundwater in affected locations. This work aims to use the concentrations of the Radon gas in the soil to identify areas contaminated by NAPL. The high affinity of the Radon for NAPLs causes a Radon deficit in soil gas in relation to the background observed in the studied region. After understanding the Radon affinity between soil gas, groundwater and NAPLs, a known contaminated area with diesel oil from a gas station spill was chosen to validate the methodology. Measurements of the Radon concentration were carried out with the AlphaGUARD® Radon monitor. These measurements confirmed the deficit in Radon concentration, which demonstrated the ability of this radionuclide to be used as a tracer for NAPL contamination, contributing to plans for remediation and control of pollution, as well as studies of oil wells on-shore. (author)
[en] Two articles comment the emergence of several technologies and demonstrators for the capture of CO2 where it is highly concentrated: in industrial smokes. A first article evokes projects and demonstrators based on the use of liquid solvents (a technology which is more advanced than the others), on kinetic and chemical innovations, on the emergence of the use of solid sorbents, on the potential of membranes and cryogenics. It also evokes another possibility: the modification of industrial processes for an easier or more efficient CO2 capture. The second article briefly evokes technologies of CO2 capture directly in the air which have now reached the industrial stage, but without having actually demonstrated their benefit for the climate
[en] The inflow of Atlantic Water to the Arctic Ocean is a crucial determinant for the future trajectory of this ocean basin with regard to warming, loss of sea ice, and ocean acidification. Yet many details of the fate and circulation of these waters within the Arctic remain unclear. Here, we use the two long-lived anthropogenic radionuclides I and U together with two age models to constrain the pathways and circulation times of Atlantic Water in the surface (10– 35 m depth) and in the mid-depth Atlantic layer (250–800m depth). We thereby benefit from the unique time-dependent tagging of Atlantic Water by these two isotopes. In the surface layer, a binary mixing model yields tracer ages of Atlantic Water between 9–16 years in the Amundsen Basin, 12–17 years in the Fram Strait (East Greenland Current), and up to 20 years in the Canada Basin, reflecting the pathways of Atlantic Water through the Arctic and their exiting through the Fram Strait. In the mid-depth Atlantic layer (250–800 m), the transit time distribution (TTD) model yields mean ages in the central Arctic ranging between 15 and 55 years, while the mode ages representing the most probable ages of the TTD range between 3 and 30 years. The estimated mean ages are overall in good agreement with previous studies using artificial radionuclides or ventilation tracers. Although we find the overall flow to be dominated by advection, the shift in the mode age towards a younger age compared to the mean age also reflects the presence of a substantial amount of lateral mixing. For applications interested in how fast signals are transported into the Arctic’s interior, the mode age appears to be a suitable measure. The short mode ages obtained in this study suggest that changes in the properties of Atlantic Water will quickly spread through the Arctic Ocean and can lead to relatively rapid changes throughout the upper water column in future years.
[en] The rare earth elements (REE) in the clay fraction of sediments in 15 rivers and their estuaries along the east coast of India were analysed in this study. The to-tal REE content (∑REE) varied from 130.98 to 289.85 μg/g and from 70.89 to 352.61 μg/g in rivers and estuaries respectively. The ∑REEs of estuarine clays (except the Brahmani and Baitarani) was lower than in rivers. The Post-Archean average Australian Shale-normalized REE patterns in rivers and estu-aries were similar and categorized into three types. The REE patterns reflect the composition of dominant geological formations in river basins and extent of sediment mixing from different sources during trans-port. Hydrodynamic conditions controlled the abun-dance and fractionation of REE in the estuaries. The Sm/Nd ratios of clays were largely controlled by mineral composition and Y/Ho ratios were affected by sedimentary processes in the estuaries. (author)
[en] In 2020, Total produced 447 units of fossil fuels for every 1 unit of renewable energy. Nonetheless, despite its desire to rename itself Total Energies, the major continues to invest heavily in the development of new fossil energy projects, such as the highly controversial EACOP oil project such as the highly controversial EACOP oil project in Uganda and Tanzania, or in the Arctic. 90% of its capital expenditure remains oriented towards fossil fuels and the trends in its hydrocarbon production could result in an increase of more than 50% between 2015 and 2030. Thus, the way French financial players are adapting their relationship with Total SE, in a context of climate emergency, is a good indicator of the sincerity of their commitments, and of the challenges related to their success. This briefing takes stock of Total SE's climate promises and of the way financial players have treated such a heavyweight in the energy sector until now. It also sketches out possible courses of action. The first follows a global approach that extends across the entirety of financial actors' portfolios and the companies they support. The second follows a sector-based approach aimed at finding immediate solutions for the most polluting sectors, which also turn out to involve the heaviest ESG and financial risks. For an oil and gas company, these are unconventional hydrocarbons - shale gas and oil, oil sands and drilling in the Arctic and deep waters. While acting on the first axis will only end up having an impact after several years, targeting the most polluting sectors makes it possible to meet the scientific imperative of reducing our greenhouse gas emissions by 7.6% every year until 20301. The actions to be taken on both axes must of course be based on science, which stipulates that oil production must be reduced by 4% and gas production by 3% per year by 2030 in order to meet the 1.5 deg. C objective.
[fr]En 2020, Total a produit 447 unites d'energies fossiles pour 1 d'energies renouvelables. Or malgre sa volonte de se renommer TotalEnergies, la major continue d'investir massivement dans le developpement de nouveaux projets d'energies fossiles, comme le tres controverse projet petrolier d'EACOP entre l'Ouganda et la Tanzanie, ou des projets d'energies fossiles en Arctique. 90% de ses depenses d'investissements demeurent orientees vers les energies fossiles et l'evolution de sa production d'hydrocarbures nous amene vers une augmentation de plus de 50% de cette derniere entre 2015 et 2030. Ainsi, la maniere dont les acteurs financiers francais adaptent leur relation a Total SE dans un contexte d'urgence climatique est un bon indicateur de la sincerite de leurs engagements precites, et des defis lies a leur succes. Ce briefing analyse les promesses climatiques du groupe, ainsi que la maniere dont les acteurs financiers ont jusqu'a present traite un tel poids lourd du secteur energetique. Il presente enfin les pistes d'actions possibles. Le premier suit une approche globale qui couvre l'integralite des portefeuilles des acteurs financiers et des entreprises qu'ils soutiennent. Le deuxieme suit une approche sectorielle visant a trouver des solutions immediates pour les secteurs les plus polluants, lesquels s'averent concentrer aussi les plus lourds risques ESG et financiers. Pour une entreprise gaziere et petroliere, il s'agit des hydrocarbures non conventionnels - gaz et petrole de schiste, sables bitumineux et forages en Arctique et en eaux tres profondes. Alors qu'agir sur le premier axe ne pourra produire des impacts qu'au bout de quelques annees, viser les secteurs les plus polluants permet de repondre a l'imperatif scientifique de baisser tous les ans nos emissions de gaz a effet de serre de 7,6% jusqu'en 20301. Les actions a mener sur les deux axes doivent bien entendu etre fondees sur la science, laquelle stipule qu'il faut baisser de 4% la production petroliere et de 3% la production gaziere par an d'ici 2030 afin de tenir l'objectif de 1,5 deg. C.
[en] The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture launched a new Coordinated Research Project (D1.50.19) called “Monitoring and Predicting Radionuclide Uptake and Dynamics for Optimizing Remediation of Radioactive Contamination in Agriculture'', in October 2019. Within the CRP, the high-throughput characterization of soil properties and the estimation of soil-to-plant transfer factors of radionuclides are of critical importance. As already highlighted in Soils Newsletter Vol. 43, No. 1, July 2020, for several decades, soil researchers have been successfully using near and mid-infrared spectroscopy (MIRS) techniques to estimate a wide range of soil properties (Carbon, Nitrogen, CEC, Clay, Sand, pH, ...). In recent years, soil science researchers are increasingly shifting their focus from traditional modeling techniques such as PLSR (Partial Least Squares Regression) to new classes of algorithms, such as Ensemble Learning (Random Forest, Boosting, …) or Deep Learning (Convolutional Neural Networks), that have proven to outperform PLSR on most (if not all) soil properties prediction in a large data regime.
[en] Under the CRP D1.50.19 focusing on the optimization of remediation of radioactive contaminated agricultural land, one important objective is to update the existing decision support system DSS4NAFA to support data management during remediation activities in the aftermath of a nuclear emergency affecting food and agriculture. During remediation, the need exists for keeping an overview of the remediation activities and, in particular, where, when and how these activities are carried out. Further, it is imperative to keep track of the efficiency and effectiveness of remediation activities (e.g. reduction of soil and food contamination). At this moment the workflow for the remediation module is being developed in close collaboration with the CRP D1.50.19 research partners from across the world for addressing the above-mentioned needs for enhanced data management during remediation.
[en] Wastewater management is one of the biggest challenges in the world due to increase in population and industrialization. In Faisalabad (FSD), wastewater treatment is being done through Wastewater Stabilization Ponds (WSPs) at Chokera, which is one of the most economical methods of Wastewater Treatment (WWT). Various parameters were examined to check wastewater treatment efficiency of the ponds under diverse climatic conditions. These included Biochemical Oxygen Demand (BOD), pH, Chemical Oxygen Demand (COD), Turbidity, Copper, Total Solids (TS), Total Dissolved Solids (TDS) and Lead. Six locations which were selected for monitoring treatment efficiency, included inlet and outlet of treatment plant, influent of anaerobic ponds, effluent of anaerobic ponds, effluent of facultative ponds, and Pharang drain before and after blending with treated sewage. The testing was performed in two seasons (i.e. Winter 2015 and Summer 2016) in Environmental Engineering Laboratory, Department of Civil Engineering, The University of Lahore, Pakistan. BOD5 removal efficiency of the treatment plant was found 30.08% in winter and 51.74% in summer against designed value of 90% removal. Most of the parameters of the effluent were not meeting the Punjab Environmental Quality Standards (PEQS). The reasons of low efficiency are; variation in climatic conditions (i.e. less solar heat intensity, wind speed and ceased microbial activity in winter), lack of funds by government, increased population, mixing of industrial sewage with domestic sewage and less attention being paid to maintain the performance of Ponds. The study was carried out to assess and compare the efficiency of treatment plant with PEQS in two climatic conditions. (author)