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Increased precipitation magnifies the effects of N addition on performance of invasive plants in subtropical native communities

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Journal of Plant Ecology 2022年第3期15卷 473-484页

作者： Xiang-Qin Li sai-Chun tang Yu-Mei Pan Chun-Qiang Wei Shi-Hong Lü Guangxi Key Laboratory of Plant Conservation and Restoration Ecology in Karst Terrain Guangxi Institute of BotanyGuangxi Zhuang Autonomous Region and Chinese Academy of SciencesGuilin 541006China Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhou 318000China

Nitrogen(N)deposition,precipitation and their interaction affect plant invasions in temperate ecosystems with limiting N and water resources,but whether and how they affect plant invasions in subtropical native communities with abundant N and precipitation remains *** constructed in situ artificial communities with 12 common native plant species in a subtropical system and introduced four common invasive plant species and their native counterparts to these *** compared plant growth and establishment of introduced invasive species and native counterparts in communities exposed to ambient(CK),N addition(N+),increased precipitation(P+)and N addition plus increased precipitation(P+N+).We also investigated the density and aboveground biomass of communities under such conditions.P+alone did not enhance the performance of invasive species or native counterparts.N+enhanced only the aboveground biomass and relative density of invasive species.P+N+enhanced the growth and establishment performance of both invasive species and native *** growth and establishment parameters of invasive species were greater than those of native counterparts under N+,P+and P+N+*** density and aboveground biomass of native communities established by invasive species were significantly lower than those of native communities established by native counterparts under P+N+*** results suggest that P+may magnify the effects of N+on performance of invasive species in subtropical native communities where N and water are often abundant,which may help to understand the effect of global change on plant invasion in subtropical ecosystems.

关键词： community aboveground biomass community density growth and establishment increased precipitation invasive plants nitrogen addition subtropical native communities

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关于樟科润楠属和鳄梨属的分类界线问题

植物分类学报 2006年第4期44卷 437-442页

作者：韦发南唐赛春广西壮族自治区中国科学院广西植物研究所桂林541006

讨论了润楠属MachilusNees与鳄梨属PerseaMill.的分类界线,认为两属的主要区别如下:在润楠属中,花被裂片相等或近相等,极少外轮明显短于内轮,在果期为纸质,极少为薄革质,伸长,强度反曲,极少张开与不反曲,几乎宿存,极少脱落,如果脱落时... 详细信息

讨论了润楠属MachilusNees与鳄梨属PerseaMill.的分类界线,认为两属的主要区别如下:在润楠属中,花被裂片相等或近相等,极少外轮明显短于内轮,在果期为纸质,极少为薄革质,伸长,强度反曲,极少张开与不反曲,几乎宿存,极少脱落,如果脱落时则内、外轮从基部完全脱落;花柱早落;分布亚洲热带及亚热带地区。而在鳄梨属中,花被裂片极不相等,外轮明显短于内轮,很少近相等,在果期为革质到木质,很少为薄革质,张开或直立,几乎不反曲,绝大部分宿存或内轮在距基部的1/3到1/2处脱落;花柱有时宿存;分布美洲。两属的界线清楚,不宜合并。把产于越南北部的PerseabalansaeAiryShaw和产于苏门答腊的***.转移到Machilus中,从而提出Machilusbalansae(AiryShaw)***&***和***(Kosterm.)***&***两个新组合。

关键词：樟科润楠属鳄梨属属的分类界线新组合

Relationship Between Credit Access and Agri-economy

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Journal of Northeast Agricultural University(English Edition) 2008年第1期15卷 91-96页

作者： tang sai WANG Jiheng PAN Wenhua WANG Tingrui ZUO Hong College of Economics and Management Northeast Agricultural University Harbin 150030 China

With the rapid development of Chinese economy, the question of credit is becoming more and more important. Especially in China rural area, building a new socialist countryside needs the support of finance. While as we all known, the financial system in rural area is not effective enough to promote the productivity and the level of welfare of household.

关键词： credit access China rural area formal finance informal finance

Distinct MLT asymmetry of auroral kilometric radiation observed by the FAST satellite

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Earth and Planetary Physics 2025年第1期9卷 188-193页

作者： JiaWen tang sai Zhang FuLiang Xiao HongMing Yang Si Liu YiHua He Chang Yang YuYue Jin ZhouKun Deng Ping Li Archie James Johnston School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hunan Province Higher Education Key Laboratory of Modeling and Monitoring on the Near-Earth Electromagnetic Environments Changsha University of Science and TechnologyChangsha 410114China School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China

Auroral Kilometric Radiation (AKR) is a common radio emission,which can contribute to the magnetosphere-ionosphereatmosphere co u *** emissions have been observed in all magnetic planet magnetospheres of the solar *** this study,using observations from the FAST satellite from 30 August 1996 to 9 September 2001,the distribution of AKR in altitude=500-4500 km and invariant latitude (|ILAT|)=60°-80°has been analyzed.63045 AKR samples have been identified with~48%(52%) samples on the dayside (nightside).Of considerable interest,there is a distinct MLT asymmetry with the high occurrence rate in MLT=05-08 and 18-22(02-05 and 12-17) in the northern (southern) *** distinct MLT asymmetry is associated with the direction of Bxof the interplaneta ry magnetic *** addition,the occurrence rate on the nightside clearly increases as the AE^(*) index *** study further enriches the information and understanding of AKR in the magnetosphere as well as other similar radio emissions.

关键词： asymmetry auroral kilometric radiation interplanetary magnetic field

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融安黄竹小穗和小花的形态发育

植物分类学报 2006年第5期44卷 551-558页

作者：唐赛春夏念和林汝顺中国科学院华南植物园

运用扫描电镜对融安黄竹Dendrocalamusronganensis的小穗和小花的发生发育及形态结构进行了研究。其小穗的发育过程是:小穗原基→第一颖片原基→第二颖片原基→第一朵小花的外稃原基→第一朵小花原基→第二朵小花的外稃原基→第二朵小... 详细信息

运用扫描电镜对融安黄竹Dendrocalamusronganensis的小穗和小花的发生发育及形态结构进行了研究。其小穗的发育过程是:小穗原基→第一颖片原基→第二颖片原基→第一朵小花的外稃原基→第一朵小花原基→第二朵小花的外稃原基→第二朵小花原基。小穗为由2个颖片和1–2朵小花组成的假小穗。其小花发育的过程是:内稃原基→雄蕊原基→雌蕊原基。内稃在发生上由彼此独立的两个突起形成,随着发育逐渐愈合。观察结果支持内稃是双起源的说法。雄蕊原基近两轮发生。雌蕊原基由小花原基的中央部分直接发育而成。在小花的发育过程中,未观察到鳞被原基的发生。该种的小花是无花被的,结构较为简化,为外稃和内稃包裹的雄蕊和雌蕊组成的结构。与近缘类群做比较,探讨了小穗和小花在竹亚科中的演化。

关键词：竹亚科融安黄竹发育演化小穗小花

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中国广西苦苣苔科一新种——灵川小花苣苔

植物分类学报 2006年第3期44卷 340-344页

作者：刘演韦毅刚唐赛春广西壮族自治区中国科学院广西植物研究所桂林541006

报道了在广西岩溶洞穴发现的苦苣苔科Gesneriaceae小花苣苔属Chiritopsis一新种——灵川小花苣苔***&***。本种因聚伞花序花稀疏,花冠白色,明显二唇形,上唇比下唇短3倍以上,退化雄蕊3而与羽裂小花苣苔***相近,区别在于前者叶不裂,雄蕊... 详细信息

报道了在广西岩溶洞穴发现的苦苣苔科Gesneriaceae小花苣苔属Chiritopsis一新种——灵川小花苣苔***&***。本种因聚伞花序花稀疏,花冠白色,明显二唇形,上唇比下唇短3倍以上,退化雄蕊3而与羽裂小花苣苔***相近,区别在于前者叶不裂,雄蕊被短柔毛。本种在叶形上还与小花苣苔***相近,不同在于后者花冠不明显二唇形,上下唇近等长,雄蕊无毛,退化雄蕊2。灵川小花苣苔的分布范围狭窄,目前仅见于一个岩溶洞穴的近洞口段,具明显的洞生习性。

关键词：小花苣苔属灵川小花苣苔苦苣苔科新种岩溶洞穴广西中国

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广西润楠属一新种—狭基润楠(英文)

热带亚热带植物学报 2008年第6期16卷 567-570页

作者：唐赛春韦发南广西壮族自治区中国科学院广西植物研究所广西桂林541006

报道了润楠属一新种，狭基润楠Machilus attenuata ***＆***。本种与形态上相似的定安润楠*** ***＆***的区别在于叶先端尾状渐尖或长渐尖，基部渐狭并略下延，幼叶上面无毛，下面疏被短柔毛；与西畴润楠*** ***的区别在于叶较小，薄革... 详细信息

报道了润楠属一新种，狭基润楠Machilus attenuata ***＆***。本种与形态上相似的定安润楠*** ***＆***的区别在于叶先端尾状渐尖或长渐尖，基部渐狭并略下延，幼叶上面无毛，下面疏被短柔毛；与西畴润楠*** ***的区别在于叶较小，薄革质，倒披针形或椭圆形，长8～13cm，宽2．2～4cm，基部渐狭，侧脉在上面明显或略明显，下面明显。

关键词：樟科润楠属狭基润楠广西中国新种