检索结果-南通市图书馆

Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji Rolf Gaël Mabicka Obame michel mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude Geffroy Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut De Chimie Des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire Des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre De Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon

引用

Open Journal of Forestry 2024年第2期14卷 127-140页

作者： Rolf Gaël Mabicka Obame Neil-Yohan Musadji Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka michel mbina Mounguengui Claude Geffroy Dé partement de Phytotechnologie Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Dé partement des Sciences Fondamentales de l&#8217Ing&#233nieur Institut National d&#8217Agronomie et de Biotechnologies Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut Agronomiques et Forestiè res Centre National des Recherches Scientifiques et Technologiques Libreville Gabon Research Centre on the Durability and the Productivity of Industrial Plantations (CRDPI) Pointe Noire Republic of Congo Laboratoire Pluridisciplinaire des Sciences &#201cole Normale Sup&#233rieure Libreville Gabon Agence Gabonaise d’ &#201tude et d&#8217Observation Spatiale Immeuble les Arcades Libreville Gabon Dé partement de G&#233ologie Faculte des Sciences Universit&#233 des Sciences et Techniques de Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux de Poitiers (IC2MP) Universit&#233 de Poitiers Poitiers France

Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha−1. Among the different regions, SOC in northern zone was significantly (p p −1) than upper layers (55.42 ± 25.37 MgC ha−1). The study highlights that low deforestation rate have led to less CO2 (705.3 Mg CO2e ha−1 - 922.62 Mg CO2e ha−1) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha−1) than primary (20.33 ± 12.7 MgC ha−1), savanna and cropland (21.71 ± 15.10 MgC ha−1). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data.

关键词： Mangroves Forest Soil Organic Carbon Stocks Rizophora Racemose Avicenia germinans Gabon

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

引用

Open Journal of Soil Science（土壤科学期刊） 2024年第4期 237页

作者： Neil-Yohan Musadji Rolf Gaël Mabicka Obame michel mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude Geffroy

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

New Computerized Method for the Geochemical Classification of Precambrian Carbonate Rocks: Case of a Set of African Cap Carbonates

引用

International Journal of Geosciences 2013年第10期4卷 37-49页

作者： Hélène Miche Roland Simler Pascal Affaton Olivia Mickala Florent Boudzoumou michel mbina Aix-Marseille Université CNRS IRD CEREGE UM 34 Aix en Provence France Département de Géologie Faculté des Sciences et Techniques Université Marien Ngouabi de Brazzaville Brazzaville République du Congo Département de Géologie Université des Sciences et Techniques de Masuku Franceville Gabon Université d’Avignon et des pays du Vaucluse INRA EMMAH UMR 1114 LHA Avignon France

Post-sedimentary transformations have masked or completely obliterated the structures and textures of Precambrian carbonate rocks. Therefore, methods of classification of the carbonate rocks founded on the observation of primary structures or textural characteristics are ill-adapted. Consequently, only certain geochemical classification methods allow us to distinguish the various rock-types in the case of Neoproterozoic carbonates. After presenting the most suitable geochemical classifications, we propose a new classification into 14 groups based on a regular ternary diagram with computerized data input. For each sample of carbonate rock, analysis of calcium and magnesium contents allows us to calculate the input data for our diagram i.e. the percentages of Calcite, Dolomite and Insoluble Residue. To automate the application of this diagram, input parameters are created in a descriptive file “***” using an option called “Ternaires” in the “Diagrammes” software developed by Roland Simler. Thirty cap carbonates of Africa are used to validate this new method.

关键词： Carbonate Rock Cap Carbonate Ternary Diagram Software Calcite Dolomite

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon

引用

Open Journal of Forestry（林学期刊） 2024年第2期 127页

作者： Rolf Gaël Mabicka Obame Neil-Yohan Musadji Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka michel mbina Mounguengui Claude Geffroy

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Growth, Duplication and Lateral Mutual Compressive Deformation of Akouemma hemisphaeria on the Seafloor of Okondja Basin at 2.2 Ga (Gabon)

引用

International Journal of Geosciences 2017年第9期8卷 1172-1191页

作者： Ambroise Edou-Minko Mathieu Moussavou Tomohiko Sato Yusuke Sawaki Simplice Ndong Ondo Richard Maire Guillaume Fleury michel mbina Mounguengui Anders Kaestner Richard Ortega Stéphane Roudeau Asuncion Carmona Makaya Mvoubou Benjamin Musavu Moussavou Osamu Sasaki Shigenori Maruyama Université des Sciences et Techniques de Masuku Franceville Gabon Earth-Life Science Institute (ELSI) Tokyo Institute of Technology Tokyo Japan Department of Earth Science and Astronomy Graduate School of Arts and Sciences The University of Tokyo Tokyo Japan UMR 5319 Passages Maison des Suds CNRS-Université Bordeaux-Montaigne Pessac France Muséum d’Histoire Naturelle de Toulouse Toulouse France Laboratory for Neutron Scattering and Imaging Paul Scherrer Institut Villigen Switzerland CENBG Univ. Bordeaux CNRS IN2P3 UMR 5797 Gradignan France Tohoku University Museum Université de Tohoku Sendai Japan

A colony of macro-fossils Akouemma hemisphaeria has been described in the Paleoproterozoic sedimentary basin of Okondja, Gabon. These fossils are classified into two groups according to their spheroidal or elongated forms. The spheroidal shapes are similar, have a tripartite structure with two hemispheres and a median disc and gradually pass to the elongated forms. These elongated forms have a pronounced bipartite tendency to two “hemispheres” separated by a median surface, and often have several ovoid “pieces” attached. The elongated specimens show both lateral growth marks and signs of fission. Growth marks are characterized by unidirectional homogeneous side elongations and lateral bud-like protuberances. The signs of fission are marked by circular furrows perpendicular to the direction of elongation, called “constriction furrows” with varying depths depending on the degree of fission of the specimen and internal vertical “division planes”. All of these ovoid and elongated specimens have undergone significant initial deformations due mainly to mutual lateral compressions in tabular beds. The Akouemma hemisphaeria macro-organisms, which were primitive probably sessile organisms, lived on the seafloor. They provide the oldest known record of macro-organisms on Earth having vegetative growth and asexual reproduction by budding, lateral elongation and fission. Their mutual lateral deformations would result from their growth.

关键词： Paleoproterozoic Francevillian Group Okondja Basin Akouemma hemisphaeria Growth Duplication

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Spectroscopic factors of resonance states with the Gamow shell model

引用

Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 38-45页

作者： Mengran Xie Jianguo Li Nicolas michel Honghui Li Wei Zuo CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

We provide an investigation of the spectroscopic factor of resonance states in A=5-8 nuclei,utilizing the Gamow shell model(GSM).Within the GSM,the configuration mixing is taken into account exactly with the shell model framework,and the continuum coupling is addressed via the complex-energy Berggren ensemble,which treats bound,resonance,and non-resonant continuum single-particle states on an equal *** a result,both the configuration mixing and continuum coupling are meticulously considered in the *** first calculate the low-lying states of helium isotopes and isotones with the GSM,and the results are compared with that of ab initio no-core shell model(NCSM)*** results indicate that GSM can reproduce the low-lying resonance states more accurately than the *** this,we delve into the spectroscopic factors of the resonance states as computed through both GSM and NCSM,concurrently conducting systematic calculations of overlap functions pertinent to these resonance ***,the calculated overlap function and spectroscopic factor of6He(01+)■νp3/2→^(7)He(3/2_(1)-)with GSM are compared with the results from ab initio NCSM,variational Monte Carlo,and Green’s function Monte Carlo calculations,as well as available experimental *** results assert that wave function asymptotes can only be reproduced in GSM,where resonance and continuum coupling are precisely addressed.

关键词： spectroscopic factor overlap function resonance states continuum coupling isospin symmetry breaking

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Demonstrating grating-based phase-contrast imaging of laser-driven shock waves

引用

Matter and Radiation at Extremes 2024年第4期9卷 90-97页

作者： Leonard Wegert Stephan Schreiner Constantin Rauch Bruno Albertazzi Paulina Bleuel Eric Frojdh michel Koenig Veronika Ludwig Artem SMartynenko Pascal Meyer Aldo Mozzanica Michael Müller Paul Neumayer Markus Schneider Angelos Triantafyllidis Bernhard Zielbauer Gisela Anton Thilo michel Stefan Funk Plasma Physics Department GSI Helmholtzzentrum fur SchwerionenforschungPlanckstraBe 164291 DarmstadtGermany Erlangen Centre for Astroparticle Physics(ECAP) Friedrich-Alexander-Universität Erlangen-NurnbergNikolaus-Fiebiger-StraBe 291058 ErlangenGermany LULI-CNRS CEASorbonne UniversitésEcole PolytechniqueInstitut Polytechnique de ParisF-91120 Palaiseau CedexFrance Paul Scherrer Institut(Psi) Forschungsstrasse 1115232VilligenSwitzerland Karlsruhe Institute of Technology Institute of Microstructure TechnologyHermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany

Single-shot X-ray phase-contrast imaging is used to take high-resolution images of laser-driven strong shock *** a two-grating Talbot interferometer,we successfully acquire standard absorption,differential phase-contrast,and dark-field images of the shocked *** agreement is demonstrated between experimental data and the results of two-dimensional radiation hydrodynamics simulations of the laser-plasma *** main sources of image noise are identified through a thorough assessment of the interferometer’s *** acquired images demonstrate that grating-based phase-contrast imaging is a powerful diagnostic tool for high-energy-density *** addition,we make a novel attempt at using the dark-field image as a signal modality of Talbot interferometry to identify the microstructure of a foam target.

关键词： interaction shock phase

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

堆石混凝土坝概述及下一代混凝土坝施工技术展望

引用

Engineering 2024年第1期32卷 99-105页

作者： Feng Jin Duruo Huang michel Lino Hu Zhou Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China ISL Ingénierie International Commission on Large DamsParis 75016France

Over the past few decades,one of the most significant advances in dam construction has been the inven-tion of the rock-filled concrete(RFC)dam,which is constructed by pouring high-performance self-compacting concrete(HSCC)to fill the voids in preplaced large *** innovative use of large rocks in dam construction provides engineers with a material that requires less cement consumption and hydration heat while enhancing construction efficiency and environmental ***,two fundamental scientific issues related to RFC need to be addressed:namely,the pouring compactness and the effect of large rocks on the mechanical and physical properties of *** article provides a timely review of fundamental research and innovations in the design,construction,and quality control of *** for next-generation concrete dams are discussed from the perspectives of envi-ronmental friendliness,intrinsic safety,and labor savings.

关键词： Rock-filled concrete dam Pouring compactness Effect of large rocks Intelligent quality control Unmanned dam construction

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Unraveling the hydrothermal history of the Xinshuijing Na-metasomatite uranium deposit in the Longshoushan metallogenic belt， Northwest China by coupled hydrothermal zircon U–Pb and albite Ar–Ar dating

引用

Journal of Earth Science 2024年

作者： JUN ZHONG MARK MIHALASKY michel CUNEY SHENG HE JUN-JIE LI National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing， Beijing Research Institute of Uranium Geology International Atomic Energy Agency (IAEA)， Nuclear Fuel Cycle and Materials Section， Division of Nuclear Fuel Cycle and Waste Technology， Vienna International Center Université de Lorraine， GéoRessources CNRS State Key Laboratory of Lithospheric Evolution (SKLLE)， Institute of Geology and Geophysics， Chinese Academy of Sciences

Na-metasomatite uranium deposits are an important type of large-tonnage low-grade uranium deposit. They are characterized by an intimate association between uranium minerals and albite， and by the common development of syn-ore hydrothermal zircons. Similar to other types of uranium deposits， constraining an accurate age of mineralization remains a challenge for the Na-metasomatite type ones. In this study， we present for the first time， an approach that combines age dating results from the syn-ore albites (40Ar-39Ar) and hydrothermal zircons （U-Pb） for a typical Na-metasomatite uranium deposit， the Xinshuijing deposit in the Longshoushan metallogenic belt of northwest China. The hydrothermal zircon U-Pb and albite40Ar-39Ar ages are consistent with each other （378-366 Ma; within error）， but also identical to the previously reported uraninite chemical U-Pb ages （approximately 370 Ma）. The coupled application of hydrothermal zircon U-Pb and albite40Ar-39Ar age dating is thus regarded as a robust approach for constraining the age of mineralization for Na-metasomatite uranium deposits. An age gap of approximately 70 m.y. between uranium mineralization （～ 370 Ma） and host granitoid emplacement （about 440 Ma） suggests no direct genetic linkage between the two. Further exploration in the surrounding metamorphic units is therefore suggested， rather than only focusing on the host granitoids， especially where intensive wallrock alteration and structural features are pervasive. The varied hydrothermal zircon δ18O isotope compositions are attributed to the significant fluid-wallrock interaction during the uranium mineralization， which is consistent with our previous fluid inclusion and geochemical studies. Our study highlights the importance of selecting appropriate isotopic dating methods， which is informed by detailed paragenetic and geochemical analysis of dateable minerals formed before or coeval to the main-stage uranium mineralization. Moreover， it is underlined that the e

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：