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Earth: Review Article
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期31-51,共21页
Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the ... Every year on 22 April, we have celebrated Earth Day and the beautiful planet we call home. Earth Day, established in 1970, has been used to highlight our planet’s environmental challenges and raise awareness of the importance of protecting our world for future generations [1]. To provide the protection of our planet, we should explain Earth’s environmental challenges to the best of our knowledge in frames of contemporary Geophysics. This paper gives a short overview of the developed Hypersphere World-Universe Model (WUM) and pay particular attention to the principal role of Dark Matter (DM) in the Earth’s life. In this manuscript, we discuss different aspects of the Earth: a condition of Young Earth before the Beginning of life on It;Internal Structure;“The 660-km Boundary” that we named Geomagma;Random Variations of Earth’s Rotational Speed on a daily basis;Origin of Moon;Expanding Earth;Internal Heating;Faint Young Sun paradox;Geocorona and Planetary Coronas;High-Energy Atmospheric Physics. WUM proposed principally different ways to solve the problems of Internal Heating, Origin of the Moon, and Faint Young Sun paradox based on DM core of the Earth. The Model revealed the fact that the Sun Activity causes the Geomagma Activity and, as a consequence, Random Variations of Earth’s Rotational Speed by the varying Sun’s magnetic field. 展开更多
关键词 Internal Structure 660-km Boundary Internal Heating Faint Young Sun Paradox Origin of Moon Expanding earth Random Variations of earth’s Rotational Speed
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基于GEOVIS Earth Studio的高中地理教学案例开发——以“河流地貌”为例
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作者 陈奕文 吕红梅 +1 位作者 杨广斌 李亦秋 《地理教学》 北大核心 2024年第2期42-46,共5页
信息技术与教学的融合发展是教育改革发展的方向,地理信息技术在教育信息化2.0时代给地理教育提供了丰富的教学资源,可有效提高教学效果。本文通过挖掘GEOVIS Earth Studio平台在地理教学中的功能优势,构建其教学应用模式,以人教版必修... 信息技术与教学的融合发展是教育改革发展的方向,地理信息技术在教育信息化2.0时代给地理教育提供了丰富的教学资源,可有效提高教学效果。本文通过挖掘GEOVIS Earth Studio平台在地理教学中的功能优势,构建其教学应用模式,以人教版必修《地理1》“河流地貌”为例阐明平台操作过程并进行案例教学设计,创新地理教学技术手段,促进中学地理教学的信息化进程。 展开更多
关键词 GEOVIS earth Studio 高中地理 虚拟动画 河流地貌
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基于Google earth engine渭-库绿洲果园遥感提取
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作者 盛艳芳 买买提·沙吾提 +1 位作者 何旭刚 李荣鹏 《江苏农业学报》 CSCD 北大核心 2024年第1期103-111,共9页
针对干旱区果园大面积遥感提取困难、识别精度低等问题,本研究基于GEE(Google earth engine)平台,综合应用Sentinel-1/Sentinel-2影像构建特征集。通过对比原始特征组合、Jeffries-Matusita(J-M)距离、属性重要度3种优化方式,结合随机森... 针对干旱区果园大面积遥感提取困难、识别精度低等问题,本研究基于GEE(Google earth engine)平台,综合应用Sentinel-1/Sentinel-2影像构建特征集。通过对比原始特征组合、Jeffries-Matusita(J-M)距离、属性重要度3种优化方式,结合随机森林(Random forest,RF)分类方法,对比得到最佳优化方式,探索果园最优分类特征集。结果表明:识别效果最好的方案为G17 JM,总体精度为91.25%,kappa系数为0.89,面积精度为82.55%。最优特征集为B8_asm、B8_ent、B8_idm、NDVI re3、B6、B7、a、e、b、EVI、B11、B8A、B8、VV。使用J-M距离进行特征集优化,有效降低数据量、提高计算效率,更有利于精确遥感识别果园种植面积。表明GEE快速、准确获取果园种植面积的可行性,为获取果园动态变化提供强有力的基础。 展开更多
关键词 Google earth engine(GEE) 特征优化 J-M距离 特征集
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基于Google Earth Engine的洱海流域建成区范围及生态质量变化分析
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作者 郑舒元 陈星宇 +1 位作者 海燕 王建雄 《湖北农业科学》 2024年第2期199-204,共6页
以洱海流域为研究区,借助Google Earth Engine云平台,利用Landsat 8 OLI系列影像,合成研究区域的增强的指数型建筑指数(EIBI)并对洱海流域建成区进行提取,再对研究区域遥感生态指数进行合成,通过对建成区范围与流域范围内遥感生态指数... 以洱海流域为研究区,借助Google Earth Engine云平台,利用Landsat 8 OLI系列影像,合成研究区域的增强的指数型建筑指数(EIBI)并对洱海流域建成区进行提取,再对研究区域遥感生态指数进行合成,通过对建成区范围与流域范围内遥感生态指数进行空间相关分析,从而对2014—2021年洱海流域及其建成区进行生态评估。结果表明,EIBI可有效增强建筑信息,使用EIBI可有效、准确地提取研究区域建成区,经过EIBI提取,洱海流域2014—2021年建成区扩张面积共14.712 km2;2014—2021年洱海流域生态明显改善,遥感生态指数增加0.008,其上升速率为0.001/年,流域内超过65%的区域生态得到改善;洱海流域建成区与生态未得到改善区域大致匹配,建成区经过生态修复后生态质量未见显著提升,且建成区生态质量呈逐年下降趋势,说明建成区对环境改善具有阻力。 展开更多
关键词 洱海流域 增强的指数型建筑指数 遥感生态指数 Google earth Engine 流域环境
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基于Google Earth Engine遥感大数据云平台的盐城盐沼植被精细分类研究
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作者 吕林 易文彬 +3 位作者 崔丹丹 王楠 张东 谢正磊 《海洋通报》 CAS CSCD 北大核心 2024年第1期114-126,共13页
江苏省自1982年开始引种互花米草以来,滨海盐沼植被景观格局发生了巨大变化,芦苇和互花米草面积不断增长,挤占了碱蓬生态位,破坏了生态系统平衡。滨海盐沼湿地是三大蓝碳生态系统之一,具有高固碳和缓解温室效应的生态功能。利用遥感云... 江苏省自1982年开始引种互花米草以来,滨海盐沼植被景观格局发生了巨大变化,芦苇和互花米草面积不断增长,挤占了碱蓬生态位,破坏了生态系统平衡。滨海盐沼湿地是三大蓝碳生态系统之一,具有高固碳和缓解温室效应的生态功能。利用遥感云平台手段监测滨海盐沼植被时空动态变化规律,可为滨海盐沼湿地生态系统保护以及修复提供科学支撑。本文选取植被类型丰富的江苏沿海地区为研究区,基于Google Earth Engine(GEE)平台,选取2000-2020年的Landsat 5、Landsat 7、Landsat 8以及Sentinel-2影像,提出了一种湿地植被提取方法。首先,构建盐城盐沼湿地地表覆盖分类体系,选取样本点,计算特征指数,进行地物分类;然后,利用时间谐波分析法对盐沼植被归一化植被指数(NDVI)变化特征进行分析,确定三类盐沼植被的物候差异;最后,基于物候特征,利用随机森林(Random Forest,RF)分类法提取盐城滨海湿地盐沼植被地表覆盖信息。结果表明:(1)相较传统监测方法,本文所构建的滨海盐沼植被精细化提取方法能够对滨海盐沼植被进行有效细分和监测;(2)2000-2020年,芦苇和互花米草面积呈扩张趋势,碱蓬面积不断缩减;(3)盐城三种典型盐沼植被NDVI值呈现不同变化特征;(4)降水对盐沼植被生长的影响较为显著,气温对盐沼植被生长的直接影响较小。研究结果可为盐城盐沼湿地自然遗产保护以及湿地生态可持续发展提供科学支撑。 展开更多
关键词 Google earth Engine 盐沼植被 特征提取 随机森林分类法 时间谐波分析
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Effect and Mechanism of Rare Earth Hydrotalcite Inhibiting Coal Spontaneous Combustion
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作者 张小娟 LIU Bo +1 位作者 罗振敏 SUN Lu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期50-59,共10页
A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition... A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%. 展开更多
关键词 rare earth HYDROTALCITE coal spontaneous combustion MECHANISM
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Note on:“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”
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作者 Andreas Heine Matthias Wickert 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期607-609,共3页
A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the ... A recently published modeling approach for the penetration into adobe and previous approaches implicitly criticized are reviewed and discussed.This article contains a note on the paper titled“Ballistic model for the prediction of penetration depth and residual velocity in adobe:A new interpretation of the ballistic resistance of earthen masonry”(DOI:https://doi.org/10.1016/j.dt.2018.07.017).Reply to the Note from Li Piani et al is linked to this article. 展开更多
关键词 ADOBE PREDICTION earth
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Wetting front migration model of ion-adsorption rare earth during the multi-hole unsaturated liquid injection
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作者 Yu Wang Xiaojun Wang +8 位作者 Yuchen Qiu Hao Wang Gang Li Kaijian Hu Wen Zhong Zhongqun Guo Bing Li Chunlei Zhang Guangxiang Ye 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期483-496,共14页
In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distanc... In the process of ion-adsorption rare earth ore leaching,the migration characteristics of the wetting front in multi-hole injection holes and the influence of wetting front intersection effect on the migration distance of wetting fronts are still unclear.Besides,wetting front migration distance and leaching time are usually required to optimize the leaching process.In this study,wetting front migration tests of ionadsorption rare earth ores during the multi-hole fluid injection(the spacing between injection holes was 10 cm,12 cm and 14 cm)and single-hole fluid injection were completed under the constant water head height.At the pre-intersection stage,the wetting front migration laws of ion-adsorption rare earth ores during the multi-hole fluid injection and single-hole fluid injection were identical.At the postintersection stage,the intersection accelerated the wetting front migration.By using the Darcy’s law,the intersection effect of wetting fronts during the multi-hole liquid injection was transformed into the water head height directly above the intersection.Finally,based on the Green-Ampt model,a wetting front migration model of ion-adsorption rare earth ores during the multi-hole unsaturated liquid injection was established.Error analysis results showed that the proposed model can accurately simulate the infiltration process under experimental conditions.The research results enrich the infiltration law and theory of ion-adsorption rare earth ores during the multi-hole liquid injection,and this study provides a scientific basis for optimizing the liquid injection well pattern parameters of ion-adsorption rare earth in situ leaching in the future. 展开更多
关键词 Ion-adsorption rare earth ore Multi-hole unsaturated liquid injection In situ leaching Intersection effect Calculation model
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Differential Expression Analysis of Proteins Regulated by Rare Earth Cerium in Soybean Leaves at Seedling Stage
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作者 Ren Hongyu Zhang Tianren +3 位作者 Miao Yanli Li Haoyang Zhang Shuying Zhang Xingwen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期42-52,共11页
This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, ... This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, Dongnong 42 was used as material, and 30 mg·L^(-1) CeCl_(3) solution was sprayed on soybean leaves at the seedling stage. Tandem mass tag(TMT) quantitative proteomics technique and bioinformatics analysis were used to identify soybean leaf proteins. A total of 8 510 proteins were identified, and 127 differentially expressed proteins(DEPs) in response to rare earth cerium regulation were identified, among which 64 were upregulated and 63 were down-regulated. The gene ontology(GO) annotation indicated that DEPs were mainly involved in metabolic process, cellular process, response to stimulus, biological regulation, and response to a stimulus;DEPs in cell module categories were mainly involved in cells, cell part, organelle, membrane, membrane part, organelle par, and protein-containing complex;DEPs in molecular functional categories were mainly involved in catalytic activity, binding and antioxidant activity. Kyoto encyclopedia of genes and genomes(KEGG) pathway significantly enriched starch and sucrose metabolism, glycolysis/gluconeogenesis, galactose metabolism, pentose phosphate pathway, and MAPK signaling pathway-plant. These DEPs were mainly involved in photosynthesis, glucose metabolism and stress response. Forty-six differential protein interaction networks were identified by protein interaction network analysis. This experiment provided a reference for studies of the mechanism of rare earth cerium regulating soybean leaf function from the proteomic perspective. 展开更多
关键词 rare earth soybean proteomics tandem mass tag(TMT)
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Effects of Desalination Processes on the Water Circulation and Earth System
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作者 Jae-Woo Choi 《Journal of Environmental Protection》 2024年第3期338-342,共5页
Desalination is emerging as a promising alternative among various technologies to resolve water shortage. However, desalination requires a sufficient energy and cooling device and therefore poses limitations for its i... Desalination is emerging as a promising alternative among various technologies to resolve water shortage. However, desalination requires a sufficient energy and cooling device and therefore poses limitations for its installation and application. In particular, many countries suffering water deficits are economically underdeveloped and cannot afford the technology. As this technology, which changes seawater into freshwater, has little environmental impact, developed countries will need to assist less developed countries to introduce this technology as a humanitarian effort. This will help reduce the number of countries that have experienced difficulty with development. 展开更多
关键词 DESALINATION earth System Humanitarian Effort Water Shortage
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Investigation of the Fermentation Mode of Rice Husk for the Stabilization of Earth Plaster
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作者 Nafissatou Savadogo Yasmine Binta Traore +2 位作者 Nathael Lankoande Philbert Nshimiyimana Adamah Messan 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期17-36,共20页
Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented ... Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented RH and to evaluate their influence on the behavior of raw earth for application in plaster. The influences of two types of RH are evaluated: granular rice husk (RHg) and powdered RH (RHp). The clay mainly consists of clay (40%), silt (22%), and sand (38.4%), with a small proportion of gravel (0.24%). Its liquidity limit is 40% and the plasticity index is 26.5%. The mixtures were designed using earth and each of the two rice husks at the volumetric content of 10%, 15% and 20% of the total volume mixed with water 36.5%, 38.5% and 40.3% and fermented for three weeks. Each fermented mixture was added to the soil to form the paste, and 40 × 40 × 160 mm<sup>3</sup> test speciments were made for characterization. The results generally show an improvement in the physico-mechanical properties and water resistance of the mortars containing fermented RH, with an optimal content between 10% and 15%. The powdered RH improved the performance of the mortar better than granular RH. 展开更多
关键词 earth Plaster Rice Husk CLAY FERMENTATION ADOBE
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Optimisation of Thermal Comfort of Building in a Hot and Dry Tropical Climate: A Comparative Approach between Compressed Earth/Concrete Block Envelopes
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作者 Arnaud Louis Sountong-Noma Ouedraogo Césaire Hema +2 位作者 Sjoerd Moustapha N’guiro Philbert Nshimiyimana Adamah Messan 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期1-16,共16页
Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid... Compressed earth blocks (CEB) are an alternative to cement blocks in the construction of wall masonry. However, the optimal architectural construction methods for adequate thermal comfort for occupants in hot and arid environments are not mastered. This article evaluates the influence of architectural and constructive modes of buildings made of CEB walls and concrete block walls, to optimize and compare their thermal comfort in the hot and dry tropical climate of Ouagadougou, Burkina Faso. Two identical pilot buildings whose envelopes are made of CEB and concrete blocks were monitored for this study. The thermal models of the pilot buildings were implemented in the SketchUp software using an extension of EnergyPlus. The models were empirically validated after calibration against measured thermal data from the buildings. The models were used to do a parametric analysis for optimization of the thermal performances by simulating plaster coatings on the exterior of walls, airtight openings and natural ventilation depending on external weather conditions. The results show that the CEB building displays 7016 hours of discomfort, equivalent to 80.1% of the time, and the concrete building displays 6948 hours of discomfort, equivalent to 79.3% of the time. The optimization by modifications reduced the discomfort to 2918 and 3125 hours respectively;i.e. equivalent to only 33.3% for the CEB building and 35.7% for the concrete building. More study should evaluate thermal optimizations in buildings in real time of usage such as residential buildings commonly used by the local middle class. The use of CEB as a construction material and passive means of improving thermal comfort is a suitable ecological and economical option to replace cementitious material. 展开更多
关键词 Compressed earth Blocks Hot and Dry Climate Thermal Comfort Architectural Optimization of Thermal Models Cement Blocks Empirical Validation
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Disorganizing rare earth ions may improve quantum infor mation storage
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《China Rare Earth Information》 2024年第1期30-31,共2页
A new paper in Nature Physics shows that by cramming lots of rare earth ions into a crystal,some will form pairs that act as highly coherent qubits,thus debunking the idea that solid-state qubits need to be super dilu... A new paper in Nature Physics shows that by cramming lots of rare earth ions into a crystal,some will form pairs that act as highly coherent qubits,thus debunking the idea that solid-state qubits need to be super dilute in an ultra-clean material to achieve long lifetimes.According to the study's authors,one of the major barriers to practical quantum computing has been how to make qubits that retain their quantum information long enough to be useful. 展开更多
关键词 QUANTUM RARE earth
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National Key Laboratory of Baiyun Obo RareEarthResourceeResearches and Comprehensive Utilization
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《China Rare Earth Information》 2024年第1期F0002-F0002,共1页
National Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization was approved by the Ministry of Science and Technology to be one of the national key laboratories in November 2022.The... National Key Laboratory of Baiyun Obo Rare Earth Resource Researches and Comprehensive Utilization was approved by the Ministry of Science and Technology to be one of the national key laboratories in November 2022.The laboratory was reconstructed based on former State Key Laboratory of Baiyun Obo Rare Earth Resources Researches and Comprehensive Utilization.The key laboratory takes Baotou Research Institute of Rare Earths as the main research body,cooperating with scientific and technological strength from Lanzhou University and Changsha Research Institute of Mining and Metallurgy. 展开更多
关键词 KEY earth LABORATORY
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Aspirations on the Bright Side of Humanity: It is Time to Translate Aspirations Into Actions With Establishing the Government of Earth
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作者 Nandor Ludvig 《Philosophy Study》 2024年第1期1-8,共8页
The thesis of this paper is that the digital noosphere of the World Wide Web and its users,the borderless move of virtually all resources of the planet,and the consequent globalization of most aspects of national poli... The thesis of this paper is that the digital noosphere of the World Wide Web and its users,the borderless move of virtually all resources of the planet,and the consequent globalization of most aspects of national politics,economy,and culture,along with the increasing difficulty of controlling the related high-tech military conflicts,human-made environmental crises,and the abnormal migrations of abused people now make it inevitable to leave behind the competitive international chaos rooted in humankind’s animal past and turn to the cooperative social spirit recommended by Aristotle,Lao Tzu,Jesus,Dante,H.G.Wells,Martin Luther King Jr.,John Lennon,Nicholas Hagger,and others to finally translate their aspirations into actions via establishing the Government of Earth for the decent and free.The paper presents a five-step,15-year,~$25B plan to start this process.That this plan has nothing to do with the Godless work of secret societies,the authoritarian urges of renewed fascism or the political absurdities of Marxism-Leninism it is relayed by the envisioned Intercontinental Education System of the outlined Government of Earth to teach every child on the planet-via a new community of digitally linked extraordinary teachers-for the beauty of lifelong learning,tolerance,duty,honor,free cooperation,and artful communication for divine missions. 展开更多
关键词 humankind Soul of Multiverse cosmological neuroscience Government of earth
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Dark Galaxies, Sun-Earth-Moon Interaction, Tunguska Event—Explained by WUM
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期836-853,共18页
Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fa... Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fact, an object the size of a galaxy, made entirely of dark matter. They found that the speed of the Earth’s rotation varies randomly each day. 115 years ago, the Tunguska Event was observed, and astronomers still do not have an explanation of It. Main results of the present article are: 1) Dark galaxies explained by the spinning of their Dark Matter Cores with the surface speed at equator less than the escape velocity. Their Rotational Fission is not happening. Extrasolar systems do not emerge;2) 21-cm Emission explained by the self-annihilation of Dark Matter particles XIONs (5.3 μeV);3) Sun-Earth-Moon Interaction explained by the influence of the Sun’s and the Moon’s magnetic field on the electrical currents of the charged Geomagma (the 660-km layer), and, as a result, the Earth’s daylength varies;4) Tunguska Event explained by a huge atmospheric explosion of the Superbolide, which was a stable Dark Matter Bubble before entering the Earth’s atmosphere. 展开更多
关键词 World-Universe Model Dark Stars Dark Galaxies 21-cm Emission Formation of Macrostructures Sun-earth-Moon Interaction Tunguska Event Dark Matter
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We Live on a Small Space Comet: The Third Extraordinary Motion of Earth towards the North Pole and Its Various Effects
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作者 Walid Nabil 《Advances in Aerospace Science and Technology》 2023年第3期21-33,共13页
The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibratio... The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibrations of traffic, and we listed successive scientific confirmations to indicate the rotation of the planet in a regular movement around its axis once every 24 hours, and it is running in another second movement around the sun once every 365¼ days, so are they only two movements, no more?! Is it possible for him to run at a regular speed in an additional direction? 展开更多
关键词 The Third Additional Regular Movement of the Planet earth towards the North Pole The Movement of the Planet earth in Space The Spiral Path of the earth The Speed of the Planet 1.3 Kilometers per Second The Planet earth A Small Space Comet
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基于GoogleEarthEngine的黄土高原植被覆盖度时空变化特征分析
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作者 姚楠 董国涛 薛华柱 《水土保持研究》 CSCD 北大核心 2024年第1期260-268,共9页
[目的]探究黄土高原植被覆盖度变化的时空特征,揭示植被对气候因子变化的时滞效应,进而为地区生态保护与高质量发展提供数据支撑。[方法]基于2001年至2020年的黄土高原地区NDVI数据、气温和降水数据,利用像元二分法、一元线性回归和时... [目的]探究黄土高原植被覆盖度变化的时空特征,揭示植被对气候因子变化的时滞效应,进而为地区生态保护与高质量发展提供数据支撑。[方法]基于2001年至2020年的黄土高原地区NDVI数据、气温和降水数据,利用像元二分法、一元线性回归和时滞偏相关分析等方法,开展地区植被与气候因子变化关系的研究。[结果]过去20年间,黄土高原植被覆盖度以0.076/10 a的速率增加,在空间上主要呈现极显著增加,但占总面积38.29%的区域植被覆盖变化波动较大。黄土高原月植被覆盖度与气温和降水呈现显著正相关关系,其中降水是影响植被变化的主要因素。植被对降水的响应滞后时间主要集中在3个月,而气温的滞后时间在空间上存在较大差异,东南部植被主要滞后0至1个月,而西北部植被主要滞后2至3个月。[结论]黄土高原植被变化主要受降水影响,20年间植被恢复情况良好,但变化波动较大,未来应继续生态保护工作进行巩固。 展开更多
关键词 植被覆盖度 GEE 时滞相关 气候变化 黄土高原
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A review of the 19th International Symposium on geodynamics and earth tide, Wuhan 2021
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作者 Xiaodong Chen Heping Sun +2 位作者 Carla Braitenberg Wei Feng Xiaoming Cui 《Geodesy and Geodynamics》 CSCD 2023年第1期4-14,共11页
Modern geodetic technologies such as high-precision ground gravity measurements,satellite gravity measurements,the global navigation satellite system,remote sensing methods,etc.provide rich observation data for monito... Modern geodetic technologies such as high-precision ground gravity measurements,satellite gravity measurements,the global navigation satellite system,remote sensing methods,etc.provide rich observation data for monitoring various geodynamic processes of the global Earth and its surface.The 19th International Symposium on Geodynamics and Earth Tides brought together scientific researchers from 26 countries around the world,shared the application of various measurements in different geoscience issues,covering Earth tidal deformation,oceanic and atmospheric loading effects,earthquake cycle,hydrology,Earth rotation changes,etc.,and provided a precious exchange platform for global peers. 展开更多
关键词 earth tides GRAVITY earthQUAKE earth rotation HYDROLOGY
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Possible Evolutionary Models in the Initially Hydride Earth Theory
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作者 Kudryavtsev Pavel 《International Journal of Geosciences》 CAS 2023年第5期377-426,共50页
A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we a... A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we attempted to find additional evidence for this hypothesis and show additional effects that flow from it. The effect of the physical properties of atoms and ions on their behavior during the formation of the Earth was studied. The maximum contribution to the distribution of elements was made by those elements whose content in the original protoplanets of the disk was the maximum. Correlation dependence is obtained, which allows one to calculate the distribution of elements in the protoplanetary disk. It was shown that hydrogen was the main element in the proto substance located in the zone of the Earth’s formation. In this case, various chemical compounds formed, most represented by hydrogen compounds—hydrides. Since the pressure inside the Earth is 375 GPa, this factor forces the chemical compounds to adopt stoichiometry and structure that would not be available in atmospheric conditions. It is shown that many chemical elements at high pressure in a hydrogen medium form simple hydrides and super hydrides—polyhydrides with high hydrogen content. Pressure leads to a higher density of matter inside the planet. Given the possibility of forming polyhydrides, there is the possibility of binding the initially available hydrogen in an amount that can reach 49.3 mole%. Young Earth could contain about 10.7 mass% of hydrogen in hydrides, polyhydrides, and adsorbed form is almost twice higher than previous estimates. This fact additionally confirms the theory of the original hydride Earth. In hydrides, the occurrence of the phenomenon of superconductivity was discovered. Polyhydrides were shown as potential superconductors with a high critical temperature above 200 K. We, based on these data, hypothesized the presence of superconducting properties in the Earth’s core, which explains the presence of a magnetic field in the Earth, as well as the unevenness and instability of this field and the possibility of migration of the Earth’s poles. The fact that the Earth has a hydroid core causes its change in time due to the instability of hydrides. Arranged several possible models of the destruction of the Earth’s core. The calculations showed that both models give close results. These results give predictions that can be measured. The proposed models also made it possible to estimate the initial size of the Earth. Possible ways of further testing the hypothesis of the initial hydride Earth is shown. 展开更多
关键词 Theory of the Hot Origin of the earth Magnetic Separation of Elements Atom Ionization Energy Hydrides Polyhydrides earth Expansion Superconductivity of the earth’s Core
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