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Comparing the Effect of CHL Background on Chinese Receptive Vocabulary Breadth Between Indonesian and Thai CS/FL Learners:A Mixed-Methods Study
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作者 Haiwei Zhang Peng Sun +1 位作者 Winda Widiawati Yaowaluk Bianglae 《Chinese Journal of Applied Linguistics》 2025年第2期241-265,321,共26页
The advantage of Chinese-as-a-heritage-language(CHL)learners in acquiring Chinese has been widely recognized.However,it is still unclear whether the effect of CHL background on Chinese receptive vocabulary breadth var... The advantage of Chinese-as-a-heritage-language(CHL)learners in acquiring Chinese has been widely recognized.However,it is still unclear whether the effect of CHL background on Chinese receptive vocabulary breadth varies across different countries.To address this gap,the present study recruited 232 Chinese language learners(half were CHL learners)from Indonesia and Thailand and administered a Chinese vocabulary proficiency test.The results of regression analysis revealed an interaction effect between country and CHL background on vocabulary breadth,with the contribution of CHL background to vocabulary breadth more robust in the Indonesian group than that in the Thai group.Interviews were then conducted to explore the factors that might influence such an interaction effect.Analysis of the interview data found that the influencing factors could be categorized into four themes,including individual differences,family background,Chinese language education and socio-cultural factors.The overall results were discussed within the framework of ecological system theory,and pedagogical implications for CHL learners were proposed. 展开更多
关键词 Chinese as a heritage language Chinese as a second/foreign language vocabulary breadth vocabulary size Thailand Indonesia
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Global, regional, and cladistic patterns of variation in climatic niche breadths in terrestrial elapid snakes 被引量:3
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作者 Long-Hui Lin Xia-Ming Zhu +2 位作者 Yu Du Meng-Chao Fang Xiang Ji 《Current Zoology》 SCIE CAS CSCD 2019年第1期1-9,共9页
We obtai ned geo-refere need occurre nee and climatic data from in dividual localities for 59 species of terrestrial elapid snakes, used phylogenetic generalized least squares regression to investigate spatial and cla... We obtai ned geo-refere need occurre nee and climatic data from in dividual localities for 59 species of terrestrial elapid snakes, used phylogenetic generalized least squares regression to investigate spatial and cladistic patter ns of variation in climatic niche breadths, and compared patter ns within and across regions and clades to see if they parallel or differ from each other. Specifically, we test (1) whether a species' climatic niche breadth on a given niche axis relates to its position along that axis, and to its climatic niche breadth on another niche axis, and (2) whether variation in niche breadths among species is explained by within-locality variation in climatic conditions or by among-locality variation. We found that:(1) there is an overall global patter n, and patter ns in individual regi ons or clades gen erally parallel each other and global patter ns;(2) species in wanner environments have narrower temperature niche breadths (TNBs);(3) precipitation niche breadth (PNB) and position are positively related;⑷ TNB and PNB are not related;and ⑸ within-locality variation in climatic conditions explains most variation in TNBs, whereas among-locality variation explains most variation in PNBs. Our results are consistent with those reported for lizards of the families Phrynosomatidae and Varanidae, con firm the importance of withi n-locality n iche breadth to species n iche breadth, and show a more im porta nt role of amon g-locality n iche breadth in affecting species niche breadth in terrestrial elapids than in lizards. 展开更多
关键词 climate ELAPIDAE NICHE breadth NICHE position NICHE variance precipitation temperature
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Investigations on Fluid Resonance Within A Narrow Gap Formed by Two Fixed Bodies with Varying Breadth Ratios 被引量:2
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作者 GONG Shu-kai GAO Jun-liang MAO Hong-fei 《China Ocean Engineering》 SCIE EI CSCD 2023年第6期962-974,共13页
The resonant motion of the fluid inside a narrow gap between two fixed boxes induced by incident regular waves with various wave heights is investigated by adopting a two-dimensional numerical wave flume based on an o... The resonant motion of the fluid inside a narrow gap between two fixed boxes induced by incident regular waves with various wave heights is investigated by adopting a two-dimensional numerical wave flume based on an opensourced CFD package,OpenFOAM.The two boxes have identical draft and height,but the upstream box has a variable breadth.This article focuses on the influences of the breadth ratio,defined as the ratio of the breadth of the upstream box to that of the downstream box,on the following three aspects of hydrodynamic characteristics of gap resonance:(1)the wave height amplifications inside the gap,and in front and at the rear of the structure system,(2)the reflection,transmission,and energy loss coefficients of the structure system,and(3)the response and damping time of the fluid resonance.It is found that the fluid resonant frequency,the amplification factor of the resonant wave height inside the gap and the maximum energy loss coefficient of the structure system are shown to gradually decrease with the increase of the breadth ratio.The response time of gap resonance is shown to first increase and then decrease with the breadth ratio overall,regardless of the incident wave height,and the configuration that the two boxes have the same breadth would bring the largest response time of gap resonance. 展开更多
关键词 gap resonance wave amplification varying breadth ratios OPENFOAM
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Macroecological Patterns of Climatic Niche Breadth Variation in Lacertid Lizards 被引量:1
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作者 Mengchao FANG Xiaming ZHU +2 位作者 Yu DU Lin ZHANG Longhui LIN 《Asian Herpetological Research》 SCIE CSCD 2019年第1期41-47,共7页
Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in cl... Measuring climatic niche position and breadth may help to determine where species can occur over space and time. Using GIS-based and phylogenetic comparative methods, we investigated global patterns of variation in climatic niche breadth in lacertid lizards to test the following three hypotheses about climatic niche widths. First, does a species' temperature or precipitation niche breadth relate to its temperature or precipitation niche position(the mean value of annual mean temperature or annual precipitation across sampled localities in the range of each species)? Second, are there trade-offs between a species' temperature niche breadth and precipitation niche breadth? Third, does a species' temperature or precipitation niche breadth relate to altitude or latitude? We expect that:(1) species distributed in cold regions are specialized for low-temperature environments(i.e. narrow niche breadth center around low temperatures);(2) a negative relationship between species niche breadth on temperature and precipitation axes according to the tradeoff hypothesis(i.e. species that tolerate a broad range of precipitation regimes cannot also tolerate a broad range of temperatures);(3) precipitation niche breadth decreases with altitude or latitude, whereas temperature climatic niche breadth increases with altitude or latitude. Based on the analytical results we found that:(1) temperature niche breadth and position are negatively related, while precipitation niche breadth and position are positively related;(2) there is no trade-off between temperature and precipitation niche breadths; and (3) temperature niche breadth and latitude/altitude are positively related, but precipitation niche breadth and latitude/altitude are not significantly related. Our results show many similarities with previous studies on climatic niche widths reported for amphibians and lizards, which provide further evidence that such macroecological patterns of variation in climatic niche breadths may be widespread. 展开更多
关键词 Macroecological pattern CLIMATIC NICHE breadth CLIMATIC NICHE POSITION LACERTIDAE
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Kinematical system of breadth cam profile design 被引量:1
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作者 SHIN Joong-ho 李琳 +1 位作者 YANG Hyun-dai KWON Soon-man 《Journal of Central South University》 SCIE EI CAS 2011年第2期451-457,共7页
The design solutions for breadth cam mechanism was presented. The main topics of the shape design for breadth cam was to calculate the coordinate at each contact point to determine the cam profile. The proposed method... The design solutions for breadth cam mechanism was presented. The main topics of the shape design for breadth cam was to calculate the coordinate at each contact point to determine the cam profile. The proposed method according to velocity and geometric relationships of instant velocity centers can easily determine each contact point at any instant moment. The cam profile was defined by contouring of the contact points. And also a program was developed by using Microsoft Visual C++ program,which can quickly and easily draw a 2D cam profile through the displacement diagram. Finally,the program was used to confirm the accuracy on the breadth cam profile design by computer animation graphically. 展开更多
关键词 cam profile breadth cam reciprocating follower oscillating follower instant velocity center
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Network Defense Methodology: A Comparison of Defense in Depth and Defense in Breadth 被引量:2
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作者 Lance Cleghorn 《Journal of Information Security》 2013年第3期144-149,共6页
The defense in depth methodology was popularized in the early 2000’s amid growing concerns for information security;this paper will address the shortcomings of early implementations. In the last two years, many suppo... The defense in depth methodology was popularized in the early 2000’s amid growing concerns for information security;this paper will address the shortcomings of early implementations. In the last two years, many supporters of the defense in depth security methodology have changed their allegiance to an offshoot method dubbed the defense in breadth methodology. A substantial portion of this paper’s body will be devoted to comparing real-world usage scenarios and discussing the flaws in each method. A major goal of this publication will be to assist readers in selecting a method that will best benefit their personal environment. Scenarios certainly exist where one method may be clearly favored;this article will help identify the factors that make one method a clear choice over another. This paper will strive not only to highlight key strengths and weaknesses for the two strategies listed, but also provide the evaluation techniques necessary for readers to apply to other popular methodologies in order to make the most appropriate personal determinations. 展开更多
关键词 DEFENSE in DEPTH DEFENSE in breadth Network DEFENSE SECURITY Architecture DEFENSE METHODOLOGY Information ASSURANCE
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Occurrence data may provide unreliable thermal preferences and breadth of species
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作者 Sara VILLEN-PEREZ Luis M. CARRASCAL 《Current Zoology》 SCIE CAS CSCD 2015年第6期972-982,共11页
Accurate information on the thermal preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to climate change. Here we estimate the position and... Accurate information on the thermal preference and specialization of species is needed to understand and predict spe- cies geographical range size and vulnerability to climate change. Here we estimate the position and breadth of species within thermal gradients based on the shape of the response curve of species abundance to temperature. The objective of the study is to compare the measurements of this approach based on abundance data with those of the classical approach using species' occur- rence data. The relationship between species' relative abundance and minimum winter temperature of 106 bird species wintering in the Iberian Peninsula is modeled at 100 Km2 resolution with quadratic logistic regressions. From these models we calculated the preferred temperature of species as the temperature at which the abundance is maximized, and the thermal breadth of species as the relative area under the temperature-abundance curve. We also estimated the thermal preferences and breadth of species as the average temperature and temperature range of the UTM cells in which the species are present. The abundance-temperature response curves reveal that birds prefer higher temperatures to overwinter, and are more thermally selective, than is measured by the classical approach. Moreover, response curves detect a higher inter-specific variability in both thermal preferences and ther- mal breadth of species. As occurrence data gives the same weight to cells with one or many individuals, the average temperature of the cells in which the species is present roughly reflects the average temperature in the region of study and not the environ- mental preferences of species . 展开更多
关键词 Abundance-temperature response curve BIRDS Species occurrence Thermal breadth Thermal preferences WINTER
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Financial depth or breadth:What really matters for fighting air pollution in China?
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作者 Wen Chen Huizhong Lu +1 位作者 Xuan Liu Ding Li 《Chinese Journal of Population,Resources and Environment》 2020年第4期331-341,共11页
China's rapid economic development leads to a series of environmental problems in the long run,such as air pollution.Environmental pollution has become a bottleneck restricting the sustainable development of China... China's rapid economic development leads to a series of environmental problems in the long run,such as air pollution.Environmental pollution has become a bottleneck restricting the sustainable development of China's economy.As such,pollution has become a key issue for China as让tries to continuously improve environmental quality and establish a harmonious coexistence between man and nature.This paper uses spatial econometric analysis to empirically test the existence of the Environmental Kuznets Curve(EKC)in China while also examining the impact of financial development on its inflection point by applying Air Quality Index and PM_(2.5) data of 283 prefecture-level cities in China from 2015 to 2017.Findings from this study indicate that the EKC of air pollution in the whole country presents an inverted U-shape based on both the traditional and new EKC models.After testing the sub-sample in different areas,the EKC still presents an inverted U-shape based on the new EKC model in the eastern and central areas,though not in the western area.In considering the moderating role of financial development based on the new EKC model,we find that the increase of financial depth will cause the EKC inflection point to shift to the left on the national scale and in the eastern region,while the effect of the financial breadth will be largely insignificant.With regard to the central area,both the breadth and the depth of financial development will significantly shift the inflection point to the right,delaying the arrival of the EKC inflection point.Therefore,the local authority of each area should formulate differentiated financial development policies to promote the early arrival of the EKC inflection point. 展开更多
关键词 EKC inflection point Air quality index Financial depth Financial breadth Regional differences
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BRI Develops in Depth and Breadth
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作者 HOU RUILI 《China Today》 2019年第5期2-2,共1页
The Second Belt and Road Forum of International Cooperation was held in Beijing in late April. Thousands of representatives from more than 100 countries around the world discussed new strategies for achieving high-qua... The Second Belt and Road Forum of International Cooperation was held in Beijing in late April. Thousands of representatives from more than 100 countries around the world discussed new strategies for achieving high-quality development of the Belt and Road Initiative (BRI) and shared cooperation experience. 展开更多
关键词 BRI Develops DEPTH breadth
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Research on Knight Covering Based on Breadth First Search Algorithm
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作者 feng wei 《International Journal of Technology Management》 2014年第7期44-45,共2页
This paper introduces the general process of the search algorithm Structure through the knight problem. According to the characteristics of the problem, we detailed discuss the DFS(Depth First Search) algorithm and ... This paper introduces the general process of the search algorithm Structure through the knight problem. According to the characteristics of the problem, we detailed discuss the DFS(Depth First Search) algorithm and BFS(Breadth First Search) algorithm, and combine the two algorithms together to solve the knights coverage problem. This article has a good reference for the mixed-use scenarios which requires a variety of search algorithms. 展开更多
关键词 Search algorithms BFS(breadth First Search) DFS(Depth First Search)
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Seasonal resource use and niche breadth in an assemblage of coexisting grazers in a fenced Park
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作者 Shem M.Mwasi Sipke E.Van Wieren +1 位作者 Ignas M.A.Heitkonig Herbert H.T.Prins 《Open Journal of Ecology》 2013年第6期383-388,共6页
Many small Parks inKenyaare being fenced to control human-wildlife conflict. Some of these Parks have a diversity of large herbivores which might increase in density in the wake of fencing and subsequent compression o... Many small Parks inKenyaare being fenced to control human-wildlife conflict. Some of these Parks have a diversity of large herbivores which might increase in density in the wake of fencing and subsequent compression of their home ranges due to closure of their migratory routes. It is important to understand the consequences of such an increase on the structuring of insularised herbivore assemblages in such Parks. We studied seasonal resource segregation and niche breadth variation as mechanisms of coexistence in a high density grazer assemblage inLakeNakuruNational Parkwhich is small and completely fenced. Diet composition and habitat use were considered as variables of resource use. We predicted that overlap in resource use and niche breadth would be the smallest among grazers with similar body weights in the dry season which is the most resource limiting for grazers in East Africa. Our results were contrary to the predictions because of lack of seasonal differentiation in the overlap of diet composition and habitat use, and in niche breadth. Overlaps in resource use were consistently high during both the wet and dry seasons, and niche breadth contraction during the dry season was not possible probably because of lack of species-specific niches during the dry season. Our results suggest that there might be competitive interactions in this grazer assemblage which is an important parameter to consider in the management of the Park. 展开更多
关键词 Niche breadth Diet Composition COEXISTENCE Habitat Use OVERLAP SEASON GRAZER Competitive Interactions
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数字经济发展对企业动态能力的影响及其机制研究——基于国家大数据综合试验区的准自然实验
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作者 焦豪 匡明慧 李楠 《科学管理研究》 北大核心 2026年第1期132-141,共10页
在市场动态变化与制度环境日益复杂的背景下,动态能力作为企业应对环境不确定性、实现资源重构与持续创新的能力体系,其影响因素成为管理学领域的研究热点。基于国家大数据综合试验区政策这一准自然实验,探讨数字经济发展对企业动态能... 在市场动态变化与制度环境日益复杂的背景下,动态能力作为企业应对环境不确定性、实现资源重构与持续创新的能力体系,其影响因素成为管理学领域的研究热点。基于国家大数据综合试验区政策这一准自然实验,探讨数字经济发展对企业动态能力的影响效应和作用机制。研究发现:数字经济发展显著提升企业动态能力,且研究结论通过平行趋势检验、PSM-DID检验和安慰剂检验等一系列稳健性检验后依然成立。路径分析表明,数字经济发展通过推动技术扩散广度和技术应用深度来提升企业动态能力。异质性分析表明,企业生命周期、生产要素密集度及政府财政补贴对数字经济发展与企业动态能力间关系存在差异性影响。从数字经济发展的角度深入剖析企业动态能力的影响机制,为企业在不确定性环境中培育和发展动态能力提供实践启示。 展开更多
关键词 数字经济发展 动态能力 技术扩散广度 技术应用深度 国家大数据综合试验区
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Assessing the Roles of Breadth and Depth of Vocabulary Knowledge in Chinese EFL Learners' Listening Comprehension 被引量:4
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作者 文卫霞 《Chinese Journal of Applied Linguistics》 2014年第3期358-372,F0003,共16页
This study intends to investigate the effects of receptive vocabulary breadth and depth on listening comprehension by college students. The experimental results indicate that both the breadth and depth have a signific... This study intends to investigate the effects of receptive vocabulary breadth and depth on listening comprehension by college students. The experimental results indicate that both the breadth and depth have a significant correlation with listening comprehension; vocabulary breadth contributes more to EFL learners' listening comprehension. The findings of this study give pedagogical implications for the teaching of listening in China. 展开更多
关键词 breadth of vocabulary knowledge depth of vocabulary knowledge listening comprehension
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黄土丘陵沟壑区不同恢复年限的林下草地与撂荒草地的群落结构特征
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作者 刘世鹏 冯艺伟 +3 位作者 李江文 野起瑞 裴婧宏 房美艳 《植物科学学报》 北大核心 2026年第1期30-40,共11页
本研究以黄土丘陵沟壑区不同恢复年限(10、20、30、40 a)的林下草本层草地(简称林下草地)和撂荒草地为对象,基于植物高度和Levins生态位宽度指数(B)分析植物群落结构特征及物种丰富度的影响因素。结果显示:试验区60个物种按生态位宽度分... 本研究以黄土丘陵沟壑区不同恢复年限(10、20、30、40 a)的林下草本层草地(简称林下草地)和撂荒草地为对象,基于植物高度和Levins生态位宽度指数(B)分析植物群落结构特征及物种丰富度的影响因素。结果显示:试验区60个物种按生态位宽度分为4类,特化种(B=1)数量最多,长期恢复阶段优势度显著提升,而泛化种(B>5)在短期恢复中占优。20 a撂荒草地的物种丰富度显著高于其他年限。植物高度分层与生态位宽度分类下的物种分布差异显著,低矮物种(≤16 cm)在撂荒草地早期丰富度较低,中等高度(>16~32 cm)在演替中期占优。物种丰富度与植物高度及Levins生态位宽度指数均呈显著单峰非线性关系,植物高度和生态位宽度指数对物种丰富度的影响更为显著,撂荒草地的丰富度始终高于林下草地。 展开更多
关键词 黄土丘陵沟壑区 恢复年限 物种多样性 植物群落结构 Levins生态位宽度指数
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人工智能影响国有企业原创技术突破的机制与效应
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作者 刘和东 谭舒尹 《科学管理研究》 北大核心 2026年第1期142-150,共9页
将人工智能与国企原创技术突破纳入统一框架,从知识宽度、资源适配等多因素分析人工智能对国企原创技术突破的影响机制;选取2013-2024年国有上市企业为研究对象,测算人工智能对其原创技术突破的影响效应。发现:①人工智能通过知识宽度... 将人工智能与国企原创技术突破纳入统一框架,从知识宽度、资源适配等多因素分析人工智能对国企原创技术突破的影响机制;选取2013-2024年国有上市企业为研究对象,测算人工智能对其原创技术突破的影响效应。发现:①人工智能通过知识宽度与资源适配显著正向影响国企原创技术突破。②整合能力显著正向调节人工智能对国企原创技术突破的促进作用。③异质性分析中,地方国企、高技术行业国企与商业一类国企的人工智能应用对原创技术突破的正向影响效应更大。研究为推进人工智能战略、促进国企原创技术突破提供理论支撑、事实检验与政策启示。 展开更多
关键词 人工智能 知识宽度 资源适配 整合能力、国企原创技术突破
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数智化转型能提升OFDI深度和广度吗?——基于价值驱动视角的实证研究 被引量:1
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作者 邓豪瀛 衣长军 张吉鹏 《外国经济与管理》 北大核心 2026年第1期132-152,共21页
面对复杂多变的国际环境,数智化转型为外向型企业提供了新增长极,通过驱动“价值跃迁”优化企业海外投资结构。以2010—2024年存在过对外直接投资(OFDI)的沪深A股上市公司为样本,在价值驱动视角下探究数智化转型对企业OFDI深度与广度的... 面对复杂多变的国际环境,数智化转型为外向型企业提供了新增长极,通过驱动“价值跃迁”优化企业海外投资结构。以2010—2024年存在过对外直接投资(OFDI)的沪深A股上市公司为样本,在价值驱动视角下探究数智化转型对企业OFDI深度与广度的影响与作用机制。研究结果表明:数智化转型作为重塑企业内部价值链的重要组织升级过程,能显著提升OFDI深度与广度;机制检验表明,数智化转型能促进企业“微笑曲线”两端进一步抬升,即通过提升企业技术价值与品牌价值来提高OFDI深度与广度。当企业将战略重心聚焦于价值创造活动,及管理层具备长期导向时,数智化转型对OFDI二元边际的促进作用将显著增强。异质性分析表明,数智化转型对OFDI二元边际的促进作用在非国有、高对外开放区域及高市场势力的企业中受益更明显。非高新技术企业数智化转型下有助于OFDI深度提高,高新技术企业在数智化转型下则更易提升OFDI广度。本研究结论为优化中国企业全球布局及实现高质量“走上去”战略提供了理论依据与实践启示。 展开更多
关键词 数智化转型 OFDI深度和广度 二元边际 微笑曲线 价值驱动
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放牧强度对羊草草甸草原植物群落组成及生态位的影响
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作者 毕鑫 俞天琦 +4 位作者 侍梦圆 辛晓平 张智涛 闫瑞瑞 韩国栋 《草地学报》 北大核心 2026年第2期403-414,共12页
为探究羊草(Leymus chinensis)草甸草原不同放牧强度下植物群落物种多样性与生态位的变化与联结,为草地资源合理利用提供依据,本研究以不同放牧强度(禁牧作为对照组G_(0)=0 cow.AU·hm^(-2),轻度放牧G_(1)=0.23cow.AU·hm^(-2)... 为探究羊草(Leymus chinensis)草甸草原不同放牧强度下植物群落物种多样性与生态位的变化与联结,为草地资源合理利用提供依据,本研究以不同放牧强度(禁牧作为对照组G_(0)=0 cow.AU·hm^(-2),轻度放牧G_(1)=0.23cow.AU·hm^(-2),轻中度放牧G_(2)=0.34 cow.AU·hm^(-2),中度放牧G_(3)=0.46 cow.AU·hm^(-2),中重度放牧G_(4)=0.69cow.AU·hm^(-2),重度放牧G_(5)=0.92 cow.AU·hm^(-2))下的羊草草甸草原植物群落为材料,通过植物群落调查,计算多样性指数及生态位指数。结果表明,随着放牧强度增加,多样性指数先升后降,在中度放牧达峰值;各处理物种重要值变化显著,羊草优势地位被寸草(Carex duriuscula)取代;重要值与生态位宽度正相关,并在轻中度放牧、中度放牧相关性最强;生态位重叠值先增后减,轻中度放牧、中度放牧种间竞争压力平稳。因此,根据物种生态位宽度与重叠值控制放牧家畜头数,进而使草地生态系统趋于稳定,有助于实现草地可持续利用。 展开更多
关键词 放牧强度 物种多样性 生态位宽度 生态位重叠 草甸草原
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酸性土和碱性土珍稀濒危植物四药门花群落乔木层主要物种生态位与种间联结差异
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作者 贾敬鹏 俞筱押 程承 《四川农业大学学报》 北大核心 2026年第1期114-121,共8页
【目的】揭示珍稀濒危植物四药门花(Loropetalum subcordatum)在酸性与碱性土壤生境中的资源利用能力与生存状态,是该物种保育、森林生态系统管理的必要支撑。【方法】整合已发表的酸性赤红壤(广东五桂山)、用相同的方法调查并计算碱性... 【目的】揭示珍稀濒危植物四药门花(Loropetalum subcordatum)在酸性与碱性土壤生境中的资源利用能力与生存状态,是该物种保育、森林生态系统管理的必要支撑。【方法】整合已发表的酸性赤红壤(广东五桂山)、用相同的方法调查并计算碱性石灰土(贵州茂兰)的四药门花群落重要值,选取乔木层重要值排名前10的物种为主要物种,采用Levins(Bi)与Shannon-Weiner(Bs)生态位宽度、Pianka(O_(ik))生态位重叠、方差比率(VR)、Pearson相关和Spearman秩相关系数等指标比较其生态位和种间联结特征。【结果】(1)四药门花的生态位宽度Bi与Bs在酸性土(4.19,1.51)均低于碱性土(4.32,1.53),说明其在酸性土资源利用范围较小;(2)四药门花与酸性土乔木层主要物种的生态位重叠平均值为0.74,≥0.90的高生态位重叠值物种占22.22%;碱性土生态位重叠平均值为0.79,≥0.90的高生态位重叠值物种占11.11%;(3)酸性土和碱性土四药门花群落乔木层主要物种总体关联均为不显著正关联(VR>1,P>0.05),物种间趋于独立,群落处于演替中期。Pearson关联性显示酸性土乔木层主要物种以竞争为主(正关联51.11%)而碱性土以互补为主(负关联64.44%),但显著或极显著关联种对少;Spearman秩相关则均为互补为主(均为51.11%),显著或极显著相关种对也少。【结论】综合生态位与联结特征,四药门花对碱性土具有更强适应性与竞争力,而在酸性土处于相对劣势,建议保育实践优先关注酸性种群的生境改良与种间竞争调控。 展开更多
关键词 珍稀濒危植物 生态位宽度 生态位重叠 种间关联 保护植物
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