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131.
E.?S.?KazakEmail author E.?G.?Kalitina N.?A.?Kharitonova G.?A.?Chelnokov E.?V.?Elovskii I.?V.?Bragin 《Moscow University Geology Bulletin》2018,73(3):287-294
This paper reports the results of the experimental determination of the coefficient of sorption of rare-earth elements and yttrium (REY) under conditions of acidic pH using several strains of heterotrophic bacteria (Microbacterium sp., Curtobacterium sp., Bacillus subtilis, Pseudomonas putida, and Bacillus pumilis) that are widespread in natural and technogenic waters of the Far East (Russia). Insignificant fractionation between heavy and light rare-earth elements, negative cerium and dysprosium anomalies, and a positive europium anomaly were revealed. The selectivity of REY biosorption by gram-positive and gram-negative bacteria, as well as inertia of the biosorption process under more acidic conditions of the medium, were shown. 相似文献
132.
V.?A.?KulikovEmail author N.?V.?Lubnina A.?Yu.?Palenov A.?V.?Solovieva 《Moscow University Geology Bulletin》2018,73(3):312-319
This work presents integrated geophysical studies that were carried out to identify the nature of the intense magnetic anomaly detected by the results of land surveying on the right bank of the Slushka River in the territory of the Yukhnovskii district of Kaluga Region. The comprehensive interpretation of the geophysical data and the laboratory measurements of the core made it possible to determine the nature and parameters of the anomaly-forming object that is located in the upper part of the section; it consists of loams that contain such magnetic minerals as greigite, pyrrhotite, and magnetite. 相似文献
133.
R.?R.?GabdullinEmail author N.?V.?Badulina E.?A.?Bakai E.?A.?Shcherbinina E.?V.?Karpova M.?A.?Varzanova A.?V.?Sergienko T.?A.?Konovalova 《Moscow University Geology Bulletin》2018,73(1):43-51
The composition and origin of the Bedenekir Formation deposits of Mountainous Crimea are detailed on the basis of our work results and analysis of both published and unpublished data. 相似文献
134.
A.?V.?StarovoitovEmail author M.?Yu.?Tokarev Ya.?E.?Terekhina N.?A.?Kozupitsa 《Moscow University Geology Bulletin》2018,73(3):295-305
The geological structure of water areas adjacent to the White Sea biological research station of Moscow State University (Rugozero Bay and Great Salma Strait; both are parts of the Kandalaksha Gulf, White Sea) was studied for the first time based on the seismoacoustic data. The morphology of the top of the Achaean basement, the structure of the Quaternary sedimentary cover, and the bottom topography were investigated. The sequence of glacial deposits dated back to the last glaciation and the compound sequence consisting of glaciolacustrine, glacial-marine, and marine sediments are distinguished. The spatial locations and changes of their thicknesses are considered. It is shown that the recent bottom topography is controlled by predominantly NW- and NE-striking faults that run through the entire sedimentary sequence, including the Holocene sediments. 相似文献
135.
E.?S.?SidkinaEmail author I.?A.?Bugaev A.?Yu.?Bychkov A.?G.?Kalmykov 《Moscow University Geology Bulletin》2018,73(4):375-379
Thermodynamic modeling of the hydrothermal exposure of the rocks of the Bazhenov Formation resulted in revealing the equilibrium mineral associations at 50–350°C and the pressure of saturated water vapor. The calculation results show that mineral parageneses varied slightly with the increase of temperature. Thus, zeolites were characterized by the stilbite–laumontite–wairakite series; kaolinite, pyrite, dolomite, and brannerite were replaced by montmorillonite and/or albite, pyrrhotite, calcite, and uraninite, respectively. The modeling results were confirmed in experiments. 相似文献
136.
T.?A.?KhusidEmail author N.?S.?Os’kina N.?P.?Lukashina I.?F.?Gablina N.?V.?Libina A.?G.?Matul 《Stratigraphy and Geological Correlation》2018,26(1):109-120
Comparison of benthic foraminiferal assemblages from the core obtained within the Peterburgskoe ore field (Mid-Atlantic Ridge) and from the core taken five kilometers away from the ore field revealed evident differences in their composition, in the appearance of their shells, and also in the benthic–plankton species ratio. It was noted that the foraminiferal assemblage from the ore-bearing sediments of the Petersburg field was characterized by a higher relative content of benthic species and a large number of chemically altered and broken shells. The first occurrence of the species Osangularia umbonifera, which is able to exist in lowoxygen and CaCO3-undersaturated bottom waters at the boundary of biogenic sediments surrounding the ore field and in the ore-bearing sediments, was established. In the core section sampled beyond the ore field, the composition of foraminiferal assemblages differs insignificantly from typical oceanic ones. 相似文献
137.
Aude?ValadeEmail authorView authors OrcID profile Sebastiaan?Luyssaert Patrick?Vallet Sylvestre?Njakou Djomo Ingride?Jesus Van Der Kellen Valentin?Bellassen 《Carbon balance and management》2018,13(1):26
Background
Concern about climate change has motivated France to reduce its reliance on fossil fuel by setting targets for increased biomass-based renewable energy production. This study quantifies the carbon costs and benefits for the French forestry sector in meeting these targets. A forest growth and harvest simulator was developed for French forests using recent forest inventory data, and the wood-use chain was reconstructed from national wood product statistics. We then projected wood production, bioenergy production, and carbon balance for three realistic intensification scenarios and a business-as-usual scenario. These intensification scenarios targeted either overstocked, harvest-delayed or currently actively managed stands.Results
All three intensification strategies produced 11.6–12.4 million tonnes of oil equivalent per year of wood-based energy by 2026, which corresponds to the target assigned to French wood-energy to meet the EU 2020 renewable energy target. Sustaining this level past 2026 will be challenging, let alone further increasing it. Although energy production targets can be reached, the management intensification required will degrade the near-term carbon balance of the forestry sector, compared to continuing present-day management. Even for the best-performing intensification strategy, i.e., reducing the harvest diameter of actively managed stands, the carbon benefits would only become apparent after 2040. The carbon balance of a strategy putting abandoned forests back into production would only break even by 2055; the carbon balance from increasing thinning in managed but untended stands would not break even within the studied time periods, i.e. 2015–2045 and 2046–2100. Owing to the temporal dynamics in the components of the carbon balance, i.e., the biomass stock in the forest, the carbon stock in wood products, and substitution benefits, the merit order of the examined strategies varies over time.Conclusions
No single solution was found to improve the carbon balance of the forestry sector by 2040 in a way that also met energy targets. We therefore searched for the intensification scenario that produces energy at the lowest carbon cost. Reducing rotation time of actively managed stands is slightly more efficient than targeting harvest-delayed stands, but in both cases, each unit of energy produced has a carbon cost that only turns into a benefit between 2060 and 2080.138.
Salim Lamine Sudhir Kumar Singh Szilárd Szabó Nour El Islam Bachari Prashant K. Srivastava 《国际地球制图》2018,33(8):862-878
This study aims to quantify the landscape spatio-temporal dynamics including Land Use/Land Cover (LULC) changes occurred in a typical Mediterranean ecosystem of high ecological and cultural significance in central Greece covering a period of 9 years (2001–2009). Herein, we examined the synergistic operation among Hyperion hyperspectral satellite imagery with Support Vector Machines, the FRAGSTATS® landscape spatial analysis programme and Principal Component Analysis (PCA) for this purpose. The change analysis showed that notable changes reported in the experimental region during the studied period, particularly for certain LULC classes. The analysis of accuracy indices suggested that all the three classification techniques are performing satisfactorily with overall accuracy of 86.62, 91.67 and 89.26% in years 2001, 2004 and 2009, respectively. Results evidenced the requirement for taking measures to conserve this forest-dominated natural ecosystem from human-induced pressures and/or natural hazards occurred in the area. To our knowledge, this is the first study of its kind, demonstrating the Hyperion capability in quantifying LULC changes with landscape metrics using FRAGSTATS® programme and PCA for understanding the land surface fragmentation characteristics and their changes. The suggested approach is robust and flexible enough to be expanded further to other regions. Findings of this research can be of special importance in the context of the launch of spaceborne hyperspectral sensors that are already planned to be placed in orbit as the NASA’s HyspIRI sensor and EnMAP. 相似文献
139.
Shahfahad Mourya Mukesh Kumari Babita Tayyab Mohammad Paarcha Aruna Asif Rahman Atiqur 《GeoJournal》2021,86(4):1607-1623
GeoJournal - The population growth in urban areas leads to the expansion of built-up area which leads to a number of serious problems like environmental pollution, destruction of urban ecology,... 相似文献
140.
Xiushu QIE Shanfeng YUAN Zhixiong CHEN Dongfeng WANG Dongxia LIU Mengyu SUN Zhuling SUN Abhay SRIVASTAVA Hongbo ZHANG Jingyu LU Hui XIAO Yongheng BI Liang FENG Ye TIAN Yan XU Rubin JIANG Mingyuan LIU Xian XIAO Shu DUAN Debin SU Chengyun SUN Wenjing XU Yijun ZHANG Gaopeng LU Da-Lin ZHANG Yan YIN Ye YU 《中国科学:地球科学(英文版)》2021,64(1):10-26
The Dynamical-microphysical-electrical Processes in Severe Thunderstorms and Lightning Hazards(STORM973)project conducted coordinated comprehensive field observations of thunderstorms in the Beijing metropolitan region(BMR)during the warm season from 2014 to 2018.The aim of the project was to understand how dynamical,microphysical and electrical processes interact in severe thunderstorms in the BMR,and how to assimilate lightning data in numerical weather prediction models to improve severe thunderstorm forecasts.The platforms used in the field campaign included the Beijing Lightning Network(BLNET,consisting of 16 stations),2 X-band dual linear polarimetric Doppler radars,and 4 laser raindrop spectrometers.The collaboration also made use of the China Meteorological Administration’s mesoscale meteorological observation network in the Beijing-Tianjin-Hebei region.Although diverse thunderstorm types were documented,it was found that squall lines and multicell storms were the two major categories of severe thunderstorms with frequent lightning activity and extreme rainfall or unexpected local short-duration heavy rainfall resulting in inundations in the central urban area,influenced by the terrain and environmental conditions.The flash density maximums were found in eastern Changping District,central and eastern Shunyi District,and the central urban area of Beijing,suggesting that the urban heat island effect has a crucial role in the intensification of thunderstorms over Beijing.In addition,the flash rate associated with super thunderstorms can reach hundreds of flashes per minute in the central city regions.The super(5%of the total),strong(35%),and weak(60%)thunderstorms contributed about 37%,56%,and 7%to the total flashes in the BMR,respectively.Owing to the close connection between lightning activity and the thermodynamic and microphysical characteristics of the thunderstorms,the lightning flash rate can be used as an indicator of severe weather events,such as hail and short-duration heavy rainfall.Lightning data can also be assimilated into numerical weather prediction models to help improve the forecasting of severe convection and precipitation at the cloud-resolved scale,through adjusting or correcting the thermodynamic and microphysical parameters of the model. 相似文献