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Classification and provenance of exotic impact glasses in Chang’e-5 lunar soil 被引量:1
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作者 YunHong Fan BiWen Wang +3 位作者 Wei Yang QiuLi Li HuiJuan Zhang ShiTou Wu 《Earth and Planetary Physics》 2025年第6期1099-1112,共14页
Lunar impact glasses have been identified as crucial indicators of geochemical information regarding their source regions. Impact glasses can be categorized as either local or exotic. Those preserving geochemical sign... Lunar impact glasses have been identified as crucial indicators of geochemical information regarding their source regions. Impact glasses can be categorized as either local or exotic. Those preserving geochemical signatures matching local lithologies (e.g., mare basalts or their single minerals) or regolith bulk soil compositions are classified as “local”. Otherwise, they could be defined as “exotic”. The analysis of exotic glasses provides the opportunity to explore previously unsampled lunar areas. This study focuses on the identification of exotic glasses within the Chang’e-5 (CE-5) soil sample by analyzing the trace elements of 28 impact glasses with distinct major element compositions in comparison with the CE-5 bulk soil. However, the results indicate that 18 of the analyzed glasses exhibit trace element compositions comparable to those of the local CE-5 materials. In particular, some of them could match the local single mineral component in major and trace elements, suggesting a local origin. Therefore, it is recommended that the investigation be expanded from using major elements to including nonvolatile trace elements, with a view to enhancing our understanding on the provenance of lunar impact glasses. To achieve a more accurate identification of exotic glasses within the CE-5 soil sample, a novel classification plot of Mg# versus La is proposed. The remaining 10 glasses, which exhibit diverse trace element variations, were identified as exotic. A comparative analysis of their chemical characteristics with remote sensing data indicates that they may have originated from the Aristarchus, Mairan, Sharp, or Pythagoras craters. This study elucidates the classification and possible provenance of exotic materials within the CE-5 soil sample, thereby providing constraints for the enhanced identification of local and exotic components at the CE-5 landing site. 展开更多
关键词 Chang’e-5 impact glass exotic materials CLASSIFICATION PROVENANCE
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Structural determination and exotic resistive behaviour ofα-RuI3 under high-pressure
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作者 Zhongxiong Sun Haili Song +2 位作者 Mei-Huan Zhao Yijie Zeng Man-Rong Li 《Chinese Journal of Structural Chemistry》 2025年第2期17-19,共3页
The exploratory synthesis and structural characterization of twodimensional(2D)honeycomb structured Ru-based compounds are key focuses in inorganic materials research,due to the various exotic electronic states arisin... The exploratory synthesis and structural characterization of twodimensional(2D)honeycomb structured Ru-based compounds are key focuses in inorganic materials research,due to the various exotic electronic states arising from the interplay of electron correlations and spinorbit coupling.Among these compounds,α-RuCl_(3) and RuBr_(3) are considered as the most promising candidates for quantum spin liquid(QSL)materials[1–3].As a homolog,α-RuI3 has attracted significant interest,but it still remains relatively unexplored.Recently,it was synthesized by high-temperature and high-pressure solid-state reaction,but reported to be different crystal structures by independent groups.Ni et al.and Nawa et al.considerα-RuI3 to be R-3(3R)and P-31c(2H)space group,respectively[4,5].Both structures have typical 2D characteristics,in which the edge-sharing RuI6 octahedra form honeycomb layers stacked along the c-axis.The primary difference lies in that the honeycomb layers stack in ABCABC mode in the 3R phase,while in ABAB mode in the 2H phase(Fig.S1).Yang et al.discussed the stability of 3R and 2H polymorphs in terms of the total energies and dynamics,finding both structures are stable.However,the total energy of the 2H phase is slightly higher,2.58 meV than that of the 3R analog[6].When it comes to the conductivity behaviour,α-RuCl3 andα-RuBr_(3) are semiconductors as normally observed in QSL materials.In contrast,α-RuI_(3) exhibits metallic response.In 2D materials,the band structure may be drastically modified by altering the stacking order[7].Hence,determining the crystal structure ofα-RuI_(3) is urgently required,which is a key step in comprehensive and in-depth analysis of its physical properties. 展开更多
关键词 high pressure two dimensional spinorbit couplingamong quantum spin exotic electronic states rui structural determination exotic resistive behaviour
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Lilium Candidum L.(Liliaceae),a New Exotic Species Reported in the Jbel Sidi Ali El Jawzi(Prerif,Morocco)
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作者 Ahmed Chriqui Ouafae Benkhnigue +4 位作者 Yassine Mouniane Issam El-Khadir Soukayna Boudik Mohammed Sghir Taleb Driss Hmouni 《Research in Ecology》 2025年第2期71-82,共12页
The genus Lilium comprises 119 taxa,primarily native to temperate and alpine regions of the Northern Hemisphere,extending to the northern Philippines.In this study,we report the first occurrence of Lilium candidum L.i... The genus Lilium comprises 119 taxa,primarily native to temperate and alpine regions of the Northern Hemisphere,extending to the northern Philippines.In this study,we report the first occurrence of Lilium candidum L.in Morocco,specifically in the jbel Sidi Ali El Jawzi area,within the territorial commune of Asjen,Ouezzane Province(Pre-Rif region).During a botanical survey conducted in May 2022,a population of L.candidum was identified,marking its first recorded presence in the country.Morphological characteristics were analyzed and compared with existing descriptions in the literature to confirm species identification.The species was found in a humid microclimate with calcareous soils,suggesting specific ecological requirements that facilitated its establishment.This unexpected discovery raises several questions regarding its biogeographical history,potential introduction pathways,and adaptation mechanisms in the Moroccan environment.Given its limited distribution and ecological specificity,its conservation status should be carefully evaluated,as human activities,habitat disturbance,and climate change may pose significant threats.Further studies,including genetic analyses and ecological monitoring,are needed to determine its origin,assess population stability,and establish conservation strategies.The presence of L.candidum in the Pre-Rif region expands the known distribution of the species and highlights the importance of continuous botanical exploration in North Africa,particularly in understudied mountainous ecosystems. 展开更多
关键词 Lilium Candidum L. LILIACEAE Exotic Flora Pre-Rif Morocco
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Species invasion and phylogenetic relatedness of vascular plants on the Qinghai-Tibet Plateau,the roof of the world
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作者 Hong Qian Tao Deng 《Plant Diversity》 2025年第6期883-888,共6页
The Qinghai-Tibet Plateau(QTP)is the highest and one of the most extensive plateaus in the world.Investigating naturalized non-native plant species composition,phylogenetic relationships among naturalized plant specie... The Qinghai-Tibet Plateau(QTP)is the highest and one of the most extensive plateaus in the world.Investigating naturalized non-native plant species composition,phylogenetic relationships among naturalized plant species,and phylogenetic relationships between native and naturalized plant species on the plateau is of great importance.Here,we analyze a comprehensive dataset including all species of native and naturalized vascular plants known to occur in the core part of the QTP.We use net relatedness index(NRI)and nearest taxon index(NTI),which reflect deep and shallow evolutionary histories,respectively,to quantify phylogenetic relatedness among angiosperm species.The QTP included in this study(1,448,815 km^(2))has 9086 and 314 species of native and naturalized non-native vascular plants,respectively.We find that the naturalized angiosperm species are phylogenetically clustered with respect to the species pool including all native and naturalized angiosperm species on the QTP included in this study,regardless of whether NRI or NTI is used.For the eight regions within the QTP included in this study,NRI and NTI of naturalized angiosperms are positive in seven regions with respect to their respective regional species pools,reflecting phylogenetic clustering.Thus,naturalized angiosperm species are a phylogenetically clustered subset of all angiosperm species on the QTP,regardless of whether the studied plateau as a whole or its constituent regions are considered. 展开更多
关键词 Community assembly Exotic species Introduced species Naturalized species Vascular plants
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A Short Review of the Vector Charmonium-Like State ψ(4230)
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作者 Qian Wang Qiang Zhao 《Chinese Physics Letters》 2025年第11期49-59,共11页
We present a concise review of the vector charmonium state ψ(4230), which was originally labelled as Y(4260)in the literature. As one of the earliest candidates for a quantum chromodynamics exotic states, its interpr... We present a concise review of the vector charmonium state ψ(4230), which was originally labelled as Y(4260)in the literature. As one of the earliest candidates for a quantum chromodynamics exotic states, its interpretation has initiated various ideas about possible manifestations of non-perturbative mechanisms in the charmonium mass regime. In this short article we briefly review the experimental status of ψ(4230) and discuss possible theoretical interpretations. We will focus on four broadly investigated scenarios, i.e., tetraquark, hybrid, hadro-quarkonium,and hadronic molecule, and highlight the key issues based on these approaches. Crucial experimental observables,e.g., mass position, lineshapes, di-lepton decay width Γ_(ee), production rates in B meson decays, dominant hadronic decay patterns, and the potential 1^(-+)and 0^(--)exotic partners, are assessed, which can provide crucial structure information for understanding this mysterious state. 展开更多
关键词 quantum chromodynamics exotic states TETRAQUARK hadro quarkonium hadronic molecule vector charmonium state hybrid y
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Production of exotic hadrons in pp and nuclear collisions
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作者 Jin-Hui Chen Feng-Kun Guo +5 位作者 Yu-Gang Ma Cheng-Ping Shen Qi-Ye Shou Qian Wang Jia-Jun Wu Bing-Song Zou 《Nuclear Science and Techniques》 2025年第4期1-22,共22页
Exotic hadrons,beyond the conventional quark model,have been discovered over the past two decades.Investigating these states can lead to a deeper understanding of the nonperturbative dynamics of the strong interaction... Exotic hadrons,beyond the conventional quark model,have been discovered over the past two decades.Investigating these states can lead to a deeper understanding of the nonperturbative dynamics of the strong interaction.In this review,we focus on the production of exotic hadrons in pp,PP^(-),and nuclear collisions.Experimental observations of light and hypernuclei as prototypes of hadronic molecules in heavy-ion collisions are also briefly discussed. 展开更多
关键词 Exotic hadrons Hadron-hadron collision Heavy-ion collision
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Perspectives for Hyperon and Hypernuclei Physics
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作者 Jin-Hui Chen Li-Sheng Geng +2 位作者 Emiko Hiyama Zhi-Wei Liu Josef Pochodzalla 《Chinese Physics Letters》 2025年第10期18-27,共10页
Hypernuclei,nuclei containing one or more hyperons,serve as unique laboratories for probing the non-perturbative quantum chromodynamics(QCD).Recent progress in hypernuclear physics,driven by advanced experimental tech... Hypernuclei,nuclei containing one or more hyperons,serve as unique laboratories for probing the non-perturbative quantum chromodynamics(QCD).Recent progress in hypernuclear physics,driven by advanced experimental techniques and theoretical innovations,is briefly reviewed with a focus on key findings and unresolved challenges,such as the precise determination of the hypertriton binding energy,investigations of charge symmetry breaking in mirror hypernuclei,and the search for exotic systems,including the neutral nnΛstate.Experimental breakthroughs,including invariant-mass analyses and femtoscopy studies in heavy-ion collisions,as well as high-resolutionγ-spectroscopy,have enabled precise studies of light hypernuclei and offered critical insights into the hyperon–nucleon interaction.Theoretical progress,including ab initio calculations based on chiral effective field theory and lattice QCD,has further enhanced our understanding of hyperon–nucleon and hyperon–hyperon interactions. 展开更多
关键词 quantum chromodynamics HYPERNUCLEI invariant mass analyses search exotic systemsincluding charge symmetry breaking hypertriton binding energyinvestigations HYPERON advanced experimental techniques
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Evidence for Mobile Gapless Spinons in a Honeycomb Lattice
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作者 Chengpeng Tu Dongzhe Dai +6 位作者 Xu Zhang Chengcheng Zhao Xiaobo Jin Bin Gao Tong Chen Pengcheng Dai Shiyan Li 《Chinese Physics Letters》 2025年第6期191-207,共17页
One important issue in current condensed matter physics is the search of quantum spin liquid(QSL),an exotic magnetic state with strongly-fluctuating and highly-entangled spins down to zero temperature without static o... One important issue in current condensed matter physics is the search of quantum spin liquid(QSL),an exotic magnetic state with strongly-fluctuating and highly-entangled spins down to zero temperature without static order.However,there is no consensus on the existence of a QSL state in any real material so far,due to inevitable disorder and intricate competing exchange interactions on frustrated spin lattices.Here we report systematic heat transport measurements on a honeycomb-lattice compound BaCo_(2)(AsO_(4))_(2),which manifests magnetic order in zero field.In a narrow in-plane field range after the magnetic order is nearly suppressed,in both perpendicular and parallel to the zigzag direction,a finite residual linear term of thermal conductivity is clearly observed,which is attributed to mobile fermionic excitations.In addition,the spin-phonon scattering rate exhibits a T-linear behavior when the order disappears.These observations suggest a partial QSL state with gapless spinon excitations in BaCo_(2)(AsO_(4))_(2),that emerges when a portion of the spins remains ordered,and vanishes as the spins become progressively polarized. 展开更多
关键词 quantum spin liquid qsl condensed matter physics competing exchange interactions systematic heat transport measurements exotic magnetic state spin latticeshere quantum spin liquid mobile gapless spinons
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椰子死亡类病毒及其传入中国的风险性分析 被引量:1
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作者 牛晓庆 朱辉 +2 位作者 余凤玉 唐庆华 覃伟权 《江西农业学报》 CAS 2010年第12期101-105,共5页
对椰子死亡类病毒(CCCVd)的国内外分布状况、潜在经济危害性、寄主植物经济重要性、传播扩散可能性和危险性管理难度等方面进行系统概述,运用多指标综合评价方法对其在我国的传播扩散风险进行评估。结果表明,CCCVd的风险性R值为2.29,属... 对椰子死亡类病毒(CCCVd)的国内外分布状况、潜在经济危害性、寄主植物经济重要性、传播扩散可能性和危险性管理难度等方面进行系统概述,运用多指标综合评价方法对其在我国的传播扩散风险进行评估。结果表明,CCCVd的风险性R值为2.29,属于高度危险入侵物种。提出了两种降低风险的备选方案,选择其中任何一种方案都能将CCCVd传入我国的风险降到最低。 展开更多
关键词 椰子 死亡 类病毒 传入中国 风险性分析 China EXOTIC SPECIES 多指标综合评价方法 传播扩散 经济危害性 系统概述 入侵物种 扩散风险 降低风险 寄主植物 管理难度 高度危险 分布状况 备选方案 危险性
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Tree species diversity, richness, and similarity between exotic and indigenous forests in the cloud forests of Eastern Arc Mountains, Taita Hills, Kenya
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作者 Loice M.A.Omoro Petri K.E.Pellikka Paul C.Rogers 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期255-264,395,共11页
Biodiversity assessment for tree species was conducted in three forest fragments ofthe Taita Hills, southeastern Kenya to compare species diversity between and within three exotic forest plantations of pine, eucalyptu... Biodiversity assessment for tree species was conducted in three forest fragments ofthe Taita Hills, southeastern Kenya to compare species diversity between and within three exotic forest plantations of pine, eucalyptus, cypress and the indigenous forests. The study sites were: Ngangao (120 ha), Chawia (86 ha), and Mbololo (185 ha). A Y-plot design was used to sample 32 plots comprising of 65 subplots. At each subplot, all juvenile trees of 5 cm and above in diameter at breast height (DBH) were enumerated and recorded by species. Tree regeneration (seedlings and saplings) was tallied by species. The Shannon-Weiner Index was used to calculate species diversity and evenness. The derived Shannon’s indices were further converted into effective numbers to show the magnitude of differences in species biodiversities. To evaluate dif-ferences in species diversities, a one way ANOVA was conducted and to separate the means, Tukey's HSD and Duncan’s tests were used for even and uneven number of samples respectively. Jaccard’s similarity index was used to assess species similarities. There were more than 58 species whose stem densities varied between 10 and 2 000 trees per hectare.There were significant differences in species diversities between forest types and sites; the indigenous forests showed higher diversities than the exotic forests. Similarly, Chawia sites had higher species diversity than both Ngangao and Mbololo. Chawia also had a higher number of regen-erated species than the two other sites, including species such as Xymalos monospora, Rapanea melanophloeos, and Syzygium guineense, which are associated with low levels of disturbance. These findings indicate that the indigenous forest is more diverse in species as would be expected in the tropics. The high species diversity in Chawia could be accounted for by the higher levels of disturbance it underwent, unlike the two other sites. The regeneration of species associated with low levels of disturbance found in the exotic plots of Chawia show the likelihood of presence of long-term soil seed banks. The low regeneration in the exotics plots observed in Ngangao and Mbololo are likely due to the absence of seed banks since some of the plantations were established on bare land (in Ngango), or the inherent physiology (allelopathy) of some of species repelling the regeneration of others. 展开更多
关键词 BIODIVERSITY forest fragments Eastern Arc Mountains DISTURBANCE exotics indigenous species
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Selection of Tree and Shrub Species for Ecological Recovery in Jari Demonstration Plot in Ethiopia
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作者 汪洋 《Journal of Landscape Research》 2010年第7期11-14,共4页
Environmental degradation and deforestation in Jari Demonstration Plot needed forestation and reforestation,and the plant species selection was a key issue in the ecological recovery.Ecological information was fully c... Environmental degradation and deforestation in Jari Demonstration Plot needed forestation and reforestation,and the plant species selection was a key issue in the ecological recovery.Ecological information was fully considered regarding each species in various agro-climatic zones,altitude ranges,specific niches in different landscapes,soil preference,drought resistance and certain other important ecological factors.The species selection model represents an idea of ecological recovery and soil erosion control in the demonstration plot. 展开更多
关键词 Jari DEMONSTRATION PLOT SPECIES SELECTION Indigenous SPECIES EXOTIC SPECIES ECOLOGICAL recovery
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Long-term monitoring revealed fish assemblage zonation in the Three Gorges Reservoir 被引量:8
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作者 LIN Pengcheng GAO Xin +2 位作者 LIU Fei LI Mingzheng LIU Huanzhang 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第4期1258-1267,共10页
Reservoirs are important artificial ecosystems that modify the hydrological and ecological characteristics of a river. Knowledge of the basic characteristics of fish assemblages in reservoirs is a first step toward th... Reservoirs are important artificial ecosystems that modify the hydrological and ecological characteristics of a river. Knowledge of the basic characteristics of fish assemblages in reservoirs is a first step toward the development of effective conservation policies. We used the information collected over a 10-year period (2006-2015) to assess the structure of the fish assemblages in the Three Gorge Reservoir (TGR) in a river-dam gradient. Three fish zones were detected in TGR. Species richness was the highest in the upper zone and lowest in the lower zone. The riverine zones were dominated by rheophilic species Coreius guichenoti and Pelteobagrus vachelli. The transitional zones were dominated by Coreius heterodon and Rhinogobio cylindricus. The lacustrine zones were dominated by eurytopic species Hypophthalmichthys molitrix, Aristichthys nobilis, Hemiculter bleekeri and Cyprinus carpio. For the functional characteristics, fish assemblages in riverine and transitional zones were dominated by insectivorous species, equilibrium strategists and rheophilic species (e.g., Coreius heterodon and Coreius guichenoti). In lacustrine zones, the fish assemblage was dominated by habitat generalists common to lakes and reservoirs (e.g., Hemiculter bleekeri, Hypophthalmichthys molitrix, Aristichthys nobilis). Moreover, 18 exotic species (e.g., Protosalanx hyalocranius, Ictalurus punctatus, Megalobrama amblycephala, Tilapia) were collected in TGR, most of which only existed in the lacustrine zone. The results highlight the importance of freely flowing riverine reaches for conserving native fish in the upper Changjiang River and adaptive management strategies for fisheries in TGR. 展开更多
关键词 longitudinal gradient IMPOUNDMENT functional GROUPS EXOTIC species DAM effects
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First proof-of-principle experiment with the post-accelerated isotope separator on-line beam at BRIF:measurement of the angular distribution of ^(23)Na+^(40)Ca elastic scattering 被引量:13
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作者 Wei Nan Bing Guo +34 位作者 Cheng-Jian Lin Lei Yang Dong-Xi Wang Yang-Ping Shen Bing Tang Bao-Qun Cui Tao Ge Yin-Long Lyu Hui-Ming Jia Yun-Ju Li Chen Chen Li-Hua Chen Qi-Wen Fan Xin-Yue Li Gang Lian Jian-Cheng Liu Tian-Peng Luo Nan-Ru Ma Rui-Gang Ma Xie Ma Ying-Jun Ma Wei-Ke Nan Dan-Yang Pang You-Bao Wang Pei-Wei Wen Feng Yang Yong-Jin Yao Sheng Zeng Hao Zhang Fu-Peng Zhong Shan-Hao Zhong Zhi-Hong Li Tian-Jue Zhang Wei-Ping Liu BRIF Collaboration 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第5期101-106,共6页
The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei... The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei.The development of rare isotope accelerators offers opportunities for such studies.To date,many relevant measurements have been performed at accelerators using the projectile fragmentation technique,while the measurements at accelerators using isotope separator on-line(ISOL)systems are still quite scarce.In this work,we present the first proof-of-principle experiment with a post-accelerated ISOL beam at the Beijing Radioactive Ion Beam Facility(BRIF)by measuring the angular distribution of elastic scattering for the stable nucleus^(23)Na from the doubly magic nucleus^(40)Ca at energies above the Coulomb barrier.The angular distribution measured by a silicon strip detector array in a scattering chamber using the ISOL beam at BRIF is in good agreement with that measured by the high-precision Q3 D magnetic spectrograph using the nonISOL beam at nearly the same energy.This work provides useful background for making BRIF a powerful tool for the investigation of the reaction dynamics of exotic nuclei. 展开更多
关键词 BRIF Exotic nuclei Elastic scattering Angular distribution
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Status and historical changes in the fish community in Erhai Lake 被引量:10
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作者 唐剑锋 叶少文 +5 位作者 李为 刘家寿 张堂林 郭志强 朱峰跃 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期712-723,共12页
Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed conside... Erhai Lake is the second largest freshwater lake on the Yunnan Plateau, Southwest China. In recent decades, a number of exotic fish species have been introduced into the lake and the fish community has changed considerably. We evaluated the status of the fish community based on surveys with multimesh gillnet, trap net, and benthic fyke-net between May 2009 and April 2012. In addition, we evaluated the change in the community using historical data (1952-2010) describing the fish community and fishery harvest. The current fish community is dominated by small-sized fishes, including Pseudorasbora parva, Rhinogobius giurinus, Micropercops swinhonis, Hemiculter leucisculus, and Rhinogobius cliffordpopei. These accounted for 87.7% of the 22 546 total specimens collected. Omnivorous and carnivorous species dominated the community. A canonical correspondence analysis (CCA) plot revealed that the distribution of fishes in the lake is influenced by aquatic plants, water temperature, pH, and season. The abundance of indigenous species has declined sharply, and a majority of endemic species have been extirpated from the lake (a decrease from seven to two species). In contrast, the number of exotic species has increased since the 1960s to a total of 22 at present. The fishery harvest decreased initially following the 1960s, but has since increased due to the introduction of non-native fish and stocking of native fish. The fishery harvest was significantly correlated with total nitrogen, not total phosphorus, during the past 20 years. Based on our results, we discuss recommendations for the restoration and conservation of the fish resources in Erhai Lake. 展开更多
关键词 Erhai Lake fish community small fishes indigenous fish species exotic fish species
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Invasive Spartina alterniflora-induced factors affecting epibenthos distribution in coastal salt marsh, China 被引量:7
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作者 XIE Wenjing GAO Shu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第2期81-88,共8页
Artificially introduced cordgrass, Spartina alterniflora, rapidly colonized the intertidal flats of the Jiangsu coast, eastern China. The epibenthos on an intertidal flat invaded by S. alterniflorawere studied, to ide... Artificially introduced cordgrass, Spartina alterniflora, rapidly colonized the intertidal flats of the Jiangsu coast, eastern China. The epibenthos on an intertidal flat invaded by S. alterniflorawere studied, to identify how local epibenthos species react to an altered environment. Epibenthic samples and surficial sediment samples were collected along a shore-normal profile in 50 quadrats at ten stations across the Spartina salt marsh; and five control quadrats for a station located on the barren sandy-mud flat. The grain size param- eters of the surficial sediments show that S. alterniflora altered the grain size gradient along the profile of the intertidal zone by trapping fine-grained sediments. Spartina alterniflora could inhabit lower elevation- s than indigenous salt marsh vegetation, thus creating larger areas of finer surficial sediments, which was suitable for not only native epibenthic species but also species which do not exist on the barren sandy-mud flat. Correlation analyses show that the epibenthos were sensitive to sediment grain size and type, on the invaded S. alterniflora salt marsh. Further, there was an interspecific relationship affecting the distribution of epibenthos. The results show that epibenthos preferred ecological niches, within the Spartina salt marsh, even in the same sampling station. 展开更多
关键词 benthos ecology exotic plant species grain size tidal-flat sedimentation Jiangsu coast
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Recent progress in two-proton radioactivity 被引量:8
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作者 Long Zhou Si-Min Wang +1 位作者 De-Qing Fang Yu-Gang Ma 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第8期118-146,共29页
During the last few decades,rare isotope beam facilities have provided unique data for studying the properties of nuclides located far from the beta-stability line.Such nuclei are often accompanied by exotic structure... During the last few decades,rare isotope beam facilities have provided unique data for studying the properties of nuclides located far from the beta-stability line.Such nuclei are often accompanied by exotic structures and radioactive modes,which represent the forefront of nuclear research.Among them,two-proton(2p)radioactivity is a rare decay mode found in a few highly proton-rich isotopes.The 2p decay lifetimes and properties of emitted protons hold invaluable information regarding the nuclear structures in the presence of a low-lying proton continuum;as such,they have attracted considerable research attention.In this review,we present some of the recent experimental and theoretical progress regarding the 2p decay,including technical innovations for measuring nucleon-nucleon correlations and developments in the models that connect their structural aspects with their decay properties.This impressive progress should play a significant role in elucidating the mechanism of these exotic decays,probing the corresponding components inside nuclei,and providing deep insights into the open quantum nature of dripline systems. 展开更多
关键词 Exotic decay Two-proton radioactivity Nucleon-nucleon correlation Experimental and theoretical development
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Differences in leaf functional traits between exotic and native Compositae plant species 被引量:5
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作者 WANG Cong-yan LIU Jun +1 位作者 ZHOU Jia-wei XIAO Hong-guang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2468-2474,共7页
This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significan... This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significantly lower than that of native species. Leaf length, specific leaf area(SLA), single-leaf wet and dry weights, leaf moisture, and leaf thickness of exotic plants were also lower than those of native species but not significantly. The leaf shape index of exotic plants was higher than that of native species but not significantly. This implies that the relatively low leaf construction cost for exotic plants may play an important role in the success of their invasions. The higher leaf shape index and lower leaf width of exotic plants can enhance the efficiency of resource capture(especially sunlight capture) via adjustments to leaf shape and size, thereby increasing the survival of exotic plants. The plasticity indices of single-leaf wet weight and leaf thickness of exotic plants were significantly lower than those of native species. The lower phenotypic plasticity of single-leaf wet weight and leaf thickness of exotic plants may be the result of a cost to plasticity. That is, if the plasticity is too high, the fitness of plant species might be reduced sharply under unfavorable environments. Thus, lower plasticity of leaf functional traits may compensate for the negative impact of adverse environments and stabilize leaf construction costs for exotic plants. Moreover, reduced phenotypic plasticity might be one of the key competitive strategies by which exotic plants successfully invade new habitats. Overall, exotic plants did not always exhibit higher values of leaf functional traits or increased phenotypic plasticity of leaf functional traits compared with native species. 展开更多
关键词 LEAF functional TRAITS specific LEAF area (SLA) PHENOTYPIC plasticity EXOTIC plants COMPOSITAE
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Urban Plant Diversity in Relation to Land Use Types in Built-up Areas of Beijing 被引量:6
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作者 GUO Peipei SU Yuebo +5 位作者 WAN Wuxing LIU Weiwei ZHANG Hongxing SUN Xu OUYANG Zhiyun WANG Xiaoke 《Chinese Geographical Science》 SCIE CSCD 2018年第1期100-110,共11页
Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field... Urban plants provide various ecosystem services and biodiversity for human well-being. It is necessary to examine the plant species and functional traits composition and the influencing factors. In this study, a field survey was conducted using the tessellation-randomized plot method to assess the plant species and functional traits variability in greenspaces across eight land use types(LUTs) in the built-up areas of Beijing, China. Results showed that the woody plants in the built-up areas of Beijing comprised 85 non-native species(57%), 21 pollen-allergenic species(14%), and 99 resistant species(67%). Residential areas, community parks and institutional areas had higher woody plant species richness than other LUTs. Native and extralimital native species were more widespread than exotic species. Proportions of species with resistances were low except for cold-and drought-resistance; consequently, a high intensity of management and maintenance is essential for survival of plants in this urban area. Caution should be exerted in selecting plant species with resistance to harsh conditions in different LUTs. Housing prices, distances from the urban center, years since the establishment of LUTs and greening rate were strongly correlated with the plant functional traits and species diversity. Urban forest managers should consider plant functional traits and LUT-specific strategies to maximize both forest and human health. 展开更多
关键词 functional trait native species extralimital native EXOTIC resistant species BEIJING
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Applications of next-generation sequencing to the study of biological invasions 被引量:5
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作者 Marc RIUS Steve BOURNE +1 位作者 Harry Guy HORNSBY Mark A. CHAPMAN 《Current Zoology》 SCIE CAS CSCD 2015年第3期488-504,共17页
Through the widespread implementation of next-generation sequencing (NGS), analyses of the whole genome (the entire DNA content) and the whole transcriptome (the genes being expressed) are becoming commonplace. ... Through the widespread implementation of next-generation sequencing (NGS), analyses of the whole genome (the entire DNA content) and the whole transcriptome (the genes being expressed) are becoming commonplace. NGS enables the analysis of a vast amount of previously unattainable genetic information. Despite this potential, NGS has yet to be widely imple- mented in genetic studies of biological invasions. The study of the genomic causes and consequences of biological invasions al- lows a deeper understanding of the molecular mechanisms underpinning the invasion process. In this review, we present a brief introduction to NGS followed by a synthesis of current research in the genomics and transcriptomics of adaptation and coloniza- tion. We then highlight research opportunities in the field, including: (1) assembling genomes and transcriptomes of non-model organisms, (2) identifying genomic regions and candidate genes underlying evolutionary processes, and (3) studying the adaptive role of gene expression variation. In particular, because introduced species face a broad range of physiological and biotic chal- lenges when colonizing novel and variable environments, transcriptomics will enable the study of gene regulatory pathways that may be responsible for acclimation or adaptation. To conclude, we identify a number of research approaches that will aid our fu- ture understanding of biological invasions 展开更多
关键词 Exotic species GENOMICS Genotype-environment interactions Invasive species Invasion genetics Invasion route Non-indigenous species Non-native species
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Genome-wide prediction for hybrids between parents with distinguished difference on exotic introgressions in Brassica napus 被引量:4
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作者 Dandan Hu Yusheng Zhao +7 位作者 Jinxiong Shen Xiangxiang He Yikai Zhang Yong Jiang Rod Snowdon Jinling Meng Jochen C.Reif Jun Zou 《The Crop Journal》 SCIE CSCD 2021年第5期1169-1178,共10页
Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can s... Extensive exotic introgression could significantly enlarge the genetic distance of hybrid parental populations to promote strong heterosis.The goal of this study was to investigate whether genome-wide prediction can support pre-breeding in populations with exotic introgressions.We evaluated seed yield,seed yield related traits and seed quality traits of 363 hybrids of Brassica napus (AACC) derived from two parental populations divergent on massive exotic introgression of related species in three environments.The hybrids presented strong heterosis on seed yield,which was much higher than other investigated traits.Five genomic best linear unbiased prediction models considering the exotic introgression and different marker effects (additive,dominance,and epistatic effects) were constructed to test the prediction ability for different traits of the hybrids.The analysis showed that the trait complexity,exotic introgression,genetic relationship between the training set and testing set,training set size,and environments affected the prediction ability.The models with best prediction ability for different traits varied.However,relatively high prediction ability (e.g.,0.728 for seed yield) was also observed when the simplest models were used,excluding the effects of the special exotic introgression and epistasis effect by5-fold cross validation,which would simplify the prediction for the trait with complex architecture for hybrids with exotic introgression.The results provide novel insights and strategies for genome-wide prediction of hybrids between genetically distinct parent groups with exotic introgressions. 展开更多
关键词 Hybrid Genome-wide prediction Exotic introgression Brassica napus HETEROSIS
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