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1.
Sébastien Gogo Jean-Baptiste Paroissien Fatima Laggoun-Défarge Jean-Marc Antoine Léonard Bernard-Jannin Guillaume Bertrand Philippe Binet Stéphane Binet Guillaume Bouger Yohann Brossard Thierry Camboulive Jean-Pierre Caudal Stéphane Chevrier Geneviève Chiapiuso Benoît D'Angelo Pilar Durantez Chris Flechard André-Jean Francez Didier Galop Laure Gandois Daniel Gilbert Christophe Guimbaud Louis Hinault Adrien Jacotot Franck Le Moing Emilie Lerigoleur Gaël Le Roux Fabien Leroy Alexandre Lhosmot Qian Li Elodie Machado Da Silva Jean-Sébastien Moquet Juanita Mora-Gomez Laurent Perdereau Thomas Rosset Marie-Laure Toussaint 《水文研究》2021,35(6):e14244
Mitigating and adapting to global changes requires a better understanding of the response of the Biosphere to these environmental variations. Human disturbances and their effects act in the long term (decades to centuries) and consequently, a similar time frame is needed to fully understand the hydrological and biogeochemical functioning of a natural system. To this end, the ‘Centre National de la Recherche Scientifique’ (CNRS) promotes and certifies long-term monitoring tools called national observation services or ‘Service National d'Observation’ (SNO) in a large range of hydrological and biogeochemical systems (e.g., cryosphere, catchments, aquifers). The SNO investigating peatlands, the SNO ‘Tourbières’, was certified in 2011 ( https://www.sno-tourbieres.cnrs.fr/ ). Peatlands are mostly found in the high latitudes of the northern hemisphere and French peatlands are located in the southern part of this area. Thus, they are located in environmental conditions that will occur in northern peatlands in coming decades or centuries and can be considered as sentinels. The SNO Tourbières is composed of four peatlands: La Guette (lowland central France), Landemarais (lowland oceanic western France), Frasne (upland continental eastern France) and Bernadouze (upland southern France). Thirty target variables are monitored to study the hydrological and biogeochemical functioning of the sites. They are grouped into four datasets: hydrology, fluvial export of organic matter, greenhouse gas fluxes and meteorology/soil physics. The data from all sites follow a common processing chain from the sensors to the public repository. The raw data are stored on an FTP server. After operator or automatic processing, data are stored in a database, from which a web application extracts the data to make them available ( https://data-snot.cnrs.fr/data-access/ ). Each year at least, an archive of each dataset is stored in Zenodo, with a digital object identifier (DOI) attribution ( https://zenodo.org/communities/sno_tourbieres_data/ ). 相似文献
2.
Izmailov I. S. Shakht N. A. Polyakov E. V. Gorshanov D. L. Pogodin M. A. 《Astrophysics》2021,64(2):160-171
Astrophysics - This paper is a continuation of our earlier work devoted to determining the orbit and mass of the star 61 Cyg and the changes in the photometric characteristics of its components.... 相似文献
3.
Sherri L. Johnson Don Henshaw Greg Downing Steve Wondzell Mark Schulze Adam Kennedy Greg Cohn Stephanie A. Schmidt Julia A. Jones 《水文研究》2021,35(5):e14187
The H. J. Andrews Experimental Forest (HJA) encompasses the 6400 ha Lookout Creek watershed in western Oregon, USA. Hydrologic, chemistry and precipitation data have been collected, curated, and archived for up to 70 years. The HJA was established in 1948 to study the effects of harvest of old-growth conifer forest and logging-road construction on water quality, quantity and vegetation succession. Over time, research questions have expanded to include terrestrial and aquatic species, communities and ecosystem dynamics. There are nine small experimental watersheds and 10 gaging stations in the HJA, including both reference and experimentally treated watersheds. Gaged watershed areas range from 8.5 to 6242 ha. All gaging stations record stage height, water conductivity, water temperature and above-stream air temperature. At nine of the gage sites, flow-proportional water samples are collected and composited over 3-week intervals for chemical analysis. Analysis of stream and precipitation chemistry began in 1968. Analytes include dissolved and particulate species of nitrogen and phosphorus, dissolved organic carbon, pH, specific conductance, suspended sediment, alkalinity, and major cations and anions. Supporting climate measurements began in the 1950s in association with the first small watershed experiments. Over time, and following the initiation of the Long Term Ecological Research (LTER) grant in 1980, infrastructure expanded to include a set of benchmark and secondary meteorological stations located in clearings spanning the elevation range within the Lookout Creek watershed, as well as a large number of forest understory temperature stations. Extensive metadata on sensor configurations, changes in methods over time, sensor accuracy and precision, and data quality control flags are associated with the HJA data. 相似文献
4.
应用PLAXIS 2D/3D有限元分析软件,对某黄土洞室进行了二维、三维分步掘进、三维一次掘进等工况的弹塑性有限元分析,研究分析了不同工况下洞室围岩位移的变化规律,并对掌子面的空间效应进行了分析。分析结果表明,二维与三维分步计算的最终位移基本一致,可以用二维的计算结果来估算洞室开挖的最终位移。三维分步掘进的分析表明,不同埋深的洞室其位移比的变化规律基本一致,当L/B<1时(L为掘进深度,B为洞室跨度),位移比呈线性增加;当L/B>1时,位移比呈非线性增加;当L/B>3时,其最大位移接近最终位移。掌子面的空间效应分析表明,在掌子面处的位移约为最终位移的1/3,距掌子面0.5倍跨度处的位移约为最终位移的2/3,距掌子面2.5倍跨度处的位移基本达到了最终位移。 相似文献
5.
Pevzner M. M. Lebedev V. A. Kuscheva Yu. V. Volynets A. O. Tolstykh M. L. Babansky A. D. 《Doklady Earth Sciences》2020,490(1):1-3
Doklady Earth Sciences - A first set of K–Ar isotopic ages obtained, which allowed to estimate the age of the largest volcanoes of the Anaunsky Dol (3.2, 2.2 and 1.9 Ma) and eruptive centers... 相似文献
6.
Chen Qiong Liu Fenggui Chen Ruijie Zhao Zhilong Zhang Yili Cui Peng Zheng Du 《地理学报(英文版)》2019,29(11):1859-1875
Journal of Geographical Sciences - The risk posed by natural disasters can be largely reflected by hazard and vulnerability. The analysis of long-term hazard series can reveal the mechanisms by... 相似文献
7.
水声目标识别技术是水声信号处理的重要组成部分,是水声信息获取与水声信息对抗的重要技术支撑。针对水声目标识别时探测数据量大、自动化程度不高、识别效率低下等问题,研究了深度学习在水声目标识别中的应用。首先,介绍了水声目标识别技术的研究现状及当前形势下面临的挑战。然后,对深度学习的网络结构原理及改进型进行了分析,并分别对深度学习在水声声信号识别领域和水声图像信号识别领域的应用现状做了阐述。最后,指出了由于受当前技术条件和水下复杂环境的制约,此方法尚且存在着不足之处。该方法为进一步优化深度学习算法、拓展深度学习技术应用范畴、提升水声目标识别效率提供了参考。 相似文献
8.
狮吼山矿区是江西省内规模最大的矽卡岩型硫铁多金属矿床,伴生W、Cu、Au多种成矿元素,成矿作用与矿区出露的茶山迳复式花岗岩体有关。岩体主要包括茶山迳似斑状黑云母二长花岗岩和莲湖细粒二长花岗岩两期,为研究成矿岩体的侵位时代、岩石成因及与成矿的关系,本次工作进行了U-Pb锆石定年、岩相学和岩石地球化学等测试分析。结果表明:岩体具有高硅、高钾、富铝的特征,属高钾钙碱性系列花岗岩;轻重稀土元素分馏明显,均为右倾型,弱Eu负异常,以富集Cs、Rb、Th、U、Pb,亏损Ba、Nb、Sr、和Ti等元素为主要特征,属于低Ba-Sr壳源花岗岩类;锆石具较好晶形,具典型岩浆锆石特征,利用LA-ICP-MS进行U-Pb测年,获得谐和年龄为(162.4±0.6)Ma(MSWD=1.8),加权平均年龄为(162.4±1.4)Ma(MSWD=1.4),谐和年龄与加权平均年龄在误差范围内高度一致,表明茶山迳复式岩体侵位于燕山早期中侏罗世;综合考虑岩体矿物组合、主微量元素及高分异特征,认为其成因分类应属于S型花岗岩;对比中国花岗岩成矿元素平均含量,茶山迳两期花岗岩均具有较高的W、Mo、Bi、Pb等成矿元素含量,可同时为成矿作用提供热源、流体及物质。 相似文献
9.
Andreev A. O. Nefedyev Yu. A. Demina N. Yu. Nefediev L. A. Petrova N. K. Zagidullin A. A. 《Astronomy Reports》2020,64(9):795-803
Astronomy Reports - The initial form of present-day space optical observations contain considerable geometrical and brightness distortions. This problem can be solved based on geometrical... 相似文献
10.
黔北镇远牛蹄塘组黑色页岩沉积环境与有机质富集关系 总被引:1,自引:0,他引:1
通过矿物组分、主量元素、微量元素、碳氧同位素等特征,分析了黔北地区镇远县ZX井牛蹄塘组黑色页岩的岩相类型和不同岩相页岩的沉积环境及其与有机质富集间的关系。结果表明,牛蹄塘组下段以硅质页岩为主,TOC含量4. 96%~10. 10%;上段以富泥硅质页岩为主,TOC含量1. 43%~9. 04%。下段硅质页岩沉积于水流停滞的深水陆棚环境,沉积古水体为贫氧的还原状态;上段富泥硅质页岩沉积时期,仍为贫氧的还原环境,但水体滞留程度、还原性较下段硅质页岩沉积期弱。贫氧的还原环境是影响牛蹄塘组黑色页岩有机质富集的主要因素,热液作用和陆源碎屑对牛蹄塘组黑色页岩有机质富集的影响较小。 相似文献