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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:1
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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Altitudinal patterns of plant diversity, cover, and life forms in a warm arid mountain: Insights from Sierra de Velasco, Argentina
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作者 Sofia V.LIZARRAGA Omar VARELA Julieta CARILLA 《Journal of Mountain Science》 2025年第3期873-887,共15页
Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored varia... Mountains are important reservoirs of biodiversity and endemism on a global scale, but little is known about the altitudinal configuration of this diversity and its driving factors in arid mountains. We explored variations in composition, diversity, cover,and life forms of vascular plants along a complete altitudinal gradient(1300-4000 m a.s.l) in Sierra de Velasco, an arid mountain in northwestern Argentina.We evaluated the influence of environmental variables on plant diversity and cover. Field sampling was conducted in the northern sector of the Sa. de Velasco,on the western slope in eight 50 m wide altitudinal bands at 400 m elevation intervals. We used rectangular plots(20 × 4 m;n:10/altitudinal band) to register the vascular plants of all the growth forms, and linear transects(20 m long.;n:30/altitudinal band) to quantify the vegetation cover using the point intercept method. Diversity was calculated using hill numbers.Data analysis included non-metric multidimensional scaling(NMDS), indicator species analysis,generalized linear models(GLMs), and variance partitioning analysis. A total of 232 species from 51families and 158 genera were registered. Species composition showed greater similarity at intermediate elevations. Plant diversity and cover exhibited a unimodal distribution, peaking at intermediate elevations(2100-2500 m). In contrast, life forms' distribution showed divergent patterns. Therophytes and succulents predominated at low altitudes,phanerophytes and hemicryptophytes at medium altitudes, and chamaephytes and geophytes at high altitudes. The altitudinal patterns of plant diversity and cover were primarily driven by climatic factors.Conservation efforts in the Sierra de Velasco should focus on the middle and upper zones due to their high biodiversity and vulnerability to climate change. 展开更多
关键词 Elevation gradient Plant diversity life forms Arid mountains Diversity pattern Climatic drivers
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Variations of plant life form diversity along the Northeast China Transect and its direct gradient analysis 被引量:2
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作者 WANGRen-zhong GAOQiong2 TANGHai-ping: 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第4期547-551,共5页
Plant life form diversity and its direct gradient analysis on a larger scale climate change gradient were tested, based on the data from Northeast China Transect platform. The results showed that the species numbers, ... Plant life form diversity and its direct gradient analysis on a larger scale climate change gradient were tested, based on the data from Northeast China Transect platform. The results showed that the species numbers, life form richness and life form diversity were relative higher at the eastern forests and the ecotone between typical vegetation, while those on the meadow grasslands and typical steppes were lower. Although plant life forms can reflect the climate variations, life form diversity is not consistent with the major global gradient along the NECT. 展开更多
关键词 northeast China transect plant life form diversity ECOTONE gradient analysis
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Life form and geographical distribution of plants in Posthband region,Khonj,Fars Province,Iran 被引量:2
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作者 Gholamhosein Moradi Mohammad Reza Marvie Mohadjer +2 位作者 Ghavamodin Zahedi Amiri Anoushirvan Shirvany Nosratollah Zargham 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期201-206,I0006,共7页
A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'3... A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'34"-53°22'30").In total,95 species belonging to 29 families and 69 genera of flora were surveyed and identified from December 2006 to June 2008.Composite and Gramineae were important families in terms of species frequency.According to Raunkiaer's system and using X^2 tests,the life-form spectrum showed that therophytes accounted for 47% of all species,and hemicryptophytes for 31%,phanerophytes for 12%,chamaeophyte for 7%,and cryptophytes for 3%.In geographical distribution,29% species with the most frequency belonged to Irano-Torunian region.Results show that therophytes were more than normal spectrum and phaneropytes were less than normal spectrum,which was in agreement with data obtained in arid climate. 展开更多
关键词 geographical distribution life form Khalije-omani forest FLORA Posthband
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Antioxidant systems of aquatic macrophytes in three life forms:a case study in Lake Erhai,China 被引量:1
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作者 YUAN Changbo ZHU Tianshun +3 位作者 CAO Te XI Yilong ZHANG Xiaolin NI Leyi 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期665-674,共10页
Antioxidant systems are vital in life activities of macrophytes.Species with diff erent life forms need to cope with distinct environments by modifying physiological characters,especially antioxidant systems.In order ... Antioxidant systems are vital in life activities of macrophytes.Species with diff erent life forms need to cope with distinct environments by modifying physiological characters,especially antioxidant systems.In order to find diff erences among life forms and consequence of lake eutrophication,we studied three antioxidant enzymes activity(superoxide dismutase(SOD),ascorbate oxidase(APX)and catalase(CAT))and total soluble phenolics(TP)content in leaves of 26 macrophyte species in September 2013 in Lake Erhai,China.We found that antioxidation varied accordingly with life forms.The activities of SOD and APX in emergent macrophytes(EM)and floating-leaved macrophytes(FM)were much lower than those of submerged macrophytes(SM).On the contrary,TP content was much higher in EM and FM species.There was a negative correlation between TP and antioxidant enzyme activities(CAT and APX).The results suggested that EM and FM species rely on phenolics might to adapt to adverse environments(higher herbivores predation pressure and UV radiation intensity),while SM species more rely on antioxidant enzymes possibly due to lower demand for antioxidation and/or lack of light and inorganic C availability for phenolics synthesis.We also found FM species represent highest fitness in term of antioxidant system,which would lead to overgrowth of FM species and littoral zone bogginess during lake eutrophication.Finally,it is necessary to carry out the verification experiment under the control condition in the later stage,especially for the dominant ones in eutrophic lakes,to understand the exact adaptive mechanisms of them. 展开更多
关键词 MACROPHYTES life forms phenolics antioxidant enzymes EUTROPHICATION
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Ecological biomass allocation strategies in plant species with different life forms in a cold desert, China 被引量:6
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作者 FAN Lianlian DING Junxiang +1 位作者 MA Xuexi LI Yaoming 《Journal of Arid Land》 SCIE CSCD 2019年第5期729-739,共11页
Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in a... Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants. 展开更多
关键词 above-ground BIOMASS BELOW-GROUND BIOMASS plant life forms HERBACEOUS species ALLOMETRIC HYPOTHESIS ISOMETRIC HYPOTHESIS Gurbantunggut Desert
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Characteristics of life-form and growth-form of plant species in an alpine ecosystem of North-West Himalaya 被引量:4
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作者 R. K. Vashistha Neelam Rawat +3 位作者 A. K. Chaturvedi B. P. Nautiyal P. Prasad M. C. Nautiyal 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期501-506,共6页
The present study was conducted in the alpine pastures of Tungnath (30° 14' N and 79° 13' E) to observe life-form and growth-form patterns of alpine plant species under grazed and ungrazed conditions and... The present study was conducted in the alpine pastures of Tungnath (30° 14' N and 79° 13' E) to observe life-form and growth-form patterns of alpine plant species under grazed and ungrazed conditions and to work out the plant life form spectrum. Species were categorized as plant habit, height and length of growth-cycle and life-form classes according to Raunkiaer's system. The results show that in total of 68 species at grazed site, hemicryptophytes (He) accounted for 50.00% species, followed by cryptophytes (26.47%), chamaephytes (16.18%), phanemphytes (4.41%) and therophytes (2.94%). At the ungrazed site in 65 plant species, hemicryptophytes (He) accounted fo'r 49.23% species, cryptophytes (26.15%), chamaephytes (15.38%), phanerophytes (6.15%) and ther6phytes (3.08 % species). In general, hemicrptophyte are dominant^in both sites i.e. graged and ungrazed. Growth form categories were classified as forbs, shrubs, grasses and sedges'and undershrubs, according to plant habit and height. On the basis of length of the growth cycle, species were categorized as plant species of short growth cycle, intermediate growth cycle and long growth cycle. The short forbs of plant habit and height, had the highest emergence, and grasses and sedges had the lowest emergence in representative species. Percentage of species with long growth cycle was highest in both sites. 展开更多
关键词 ALPINE biological spectrum growth form HIMALAYA life
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Functional Enrichment of Utopian Distribution of Plant Life-Forms
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作者 James N. Furze Quanmin Zhu +1 位作者 Feng Qiao Jennifer Hill 《American Journal of Plant Sciences》 2013年第12期37-48,共12页
Adaptive fuzzy neural inference systems are used to illustrate the primary nodal number of plant life-forms. Categorization of two candidate areas is carried out using the water-energy dynamic (for Ecuador, South Amer... Adaptive fuzzy neural inference systems are used to illustrate the primary nodal number of plant life-forms. Categorization of two candidate areas is carried out using the water-energy dynamic (for Ecuador, South America) and Macedonia, Southern Europe), within which the life-form spectra are distributed. Genetic optimization methods are used to expand the primary nodal number to the complete number of life-form categories. The distribution of the elements exhibits a stochastic, binomial distribution and the utopia line and curve are summarized which enhance accuracy of the climatic data and of the consequent numbers of plant species occurrences. Expansion of the distribution of each life-form category is approximated within the Z utopia hyperplane with use of the functional approximation algorithm. This process gives additional structure and informative value to the Z plane, enhancing our ability to make informed policy decisions concerning species and ecosystem conservation. 展开更多
关键词 Adaptive Neural Fuzzy Inference System PLANT life-form Genetic Optimization Stochastic UTOPIA FUNCTIONAL Approximation Algorithm
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呼伦贝尔草原外来植物种类调查
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作者 李杰 黄学文 +1 位作者 肖燕子 特喜铁 《草原与草坪》 2025年第4期75-82,共8页
【目的】掌握呼伦贝尔草原外来植物种类组成、生活型、原产地、引入途径等,为今后该地区外来植物的管理与防控奠定理论基础。【方法】在野外调查的基础上,通过查阅相关文献,对呼伦贝尔草原区外来植物进行调查和统计。【结果】呼伦贝尔... 【目的】掌握呼伦贝尔草原外来植物种类组成、生活型、原产地、引入途径等,为今后该地区外来植物的管理与防控奠定理论基础。【方法】在野外调查的基础上,通过查阅相关文献,对呼伦贝尔草原区外来植物进行调查和统计。【结果】呼伦贝尔草原区共有外来植物50种,隶属于17科43属,其中,种数排名前三位的分别为菊科11种,占总种数的22%,禾本科9种,占总种数的18%,苋科5种,占总种数的10%;生活型方面,一年生草本植物最多,共有28种,占总种数的56%;原产地为美洲的物种最多,为17种,占总种数的36%;引入途径中,有意引进和无意引进分别占总种数的52%和48%。【结论】呼伦贝尔草原区外来植物种类较多,以菊科、苋科和禾本科为主;生活型组成以一年生植物为主,原产自美洲的种类最多;科的分布区类型以热带成分为主,属的层面上以温带成分为主。 展开更多
关键词 呼伦贝尔草原 外来植物 生活型 引入途径 原产地 区系
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Climate space,traits,and the spread of nonnative plants in North America
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作者 Qinfeng Guo Hong Qian Shenhua Qian 《Plant Diversity》 2025年第2期255-263,共9页
The future distribution of invading species depends on the climate space available and certain life history traits that facilitate invasion.Here,to predict the spread potential of plant species introduced in North Ame... The future distribution of invading species depends on the climate space available and certain life history traits that facilitate invasion.Here,to predict the spread potential of plant species introduced in North America north of Mexico(NAM),we compiled distribution and life history data(i.e.,seed size,life form,and photosynthetic pathways)for 3021 exotic plant species introduced to NAM.We comparatively examined the species’range size and climate space in both native and exotic regions and the role of key life history traits.We found that large climate space for most exotic plants is still available in NAM.The range sizes in global exotic regions could better predict the current range sizes in NAM than those in global native regions or global native plus exotic regions.C3 species had larger ranges on average than C4 and CAM plants,and herbaceous species consistently showed stronger relationships in range size between native and exotic regions than woody species,as was the case within the C3 species group.Seed size was negatively related to range size both in native regions and in NAM.However,seed size surprisingly showed a positive correlation with global exotic range size and no correlation with the current actual global(native plus exotic)range size.Our findings underline the importance of species’native distribution and life history traits in predicting the spread of exotic species.Future studies should continue to identify potential climate space and use underappreciated species traits to better predict species invasions under changing climate. 展开更多
关键词 Climate-matching Biological invasion life form NICHE Photosynthetic pathway Seed size
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Assessment of plant diversity in the Surkhan-Sherabad Region,Uzbekistan by grid mapping
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作者 Inom JURAMURODOV Rustam URALOV +6 位作者 Dilmurod MAKHMUDJANOV LU Chunfang Feruz AKBAROV Sardor PULATOV Bakhtiyor KARIMOV Orzimat TURGINOV Komiljon TOJIBAEV 《Journal of Arid Land》 2025年第3期394-410,共17页
In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a th... In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups. 展开更多
关键词 grid mapping species richness collection density TAXONOMY dominant species life form therophyte Central Asia
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Influence of nitrogen inputs on biomass allocation strategies of dominant plant species in sandy ecosystems
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作者 CHENG Li ZHAN Jin +1 位作者 NING Zhiying LI Yulin 《Journal of Arid Land》 2025年第8期1118-1146,共29页
Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a va... Understanding how dominant plants respond to nitrogen(N)addition is critical for accurately predicting the potential effects of N deposition on ecosystem structure and functionality.Biomass partitioning serves as a valuable indicator for assessing plant responses to environmental changes.However,considerable uncertainty remains regarding how biomass partitioning shifts with increasing N inputs in sandy ecosystems.To address this gap,we conducted a greenhouse N fertilization experiment in April 2024,using seeds from 20 dominant plant species in the Horqin Sandy Land of China representing 5 life forms:annual grasses,annual forbs,perennial grasses,perennial forbs,and shrubs.Six levels of N addition(0.0,3.5,7.0,14.0,21.0,and 49.0 g N/(m2•a),referred to as N0,N1,N2,N3,N4,and N5,respectively)were applied to investigate the effects of N inputs on biomass partitioning.Results showed that for all 20 dominant plant species,the root biomass:shoot biomass(R:S)consistently declined across all N addition treatments(P<0.050).Concurrently,N addition led to a 23.60%reduction in root biomass fraction,coupled with a 12.38%increase in shoot biomass fraction(P<0.050).Allometric partitioning analysis further indicated that N addition had no significant effect on the slopes of the allometric relationships(leaf biomass versus root biomass,stem biomass versus root biomass,and shoot biomass versus root biomass).This suggests that plants can adjust resource investment—such as allocating more resources to shoots—to optimize growth under favorable conditions without disrupting functional trade-offs between organs.Among different life forms,annual grasses,perennial grasses,and annual forbs exhibited increased allocation to aboveground biomass,enhancing productivity and potentially altering community composition and competitive hierarchies.In contrast,perennial forbs and shrubs maintained stable biomass partitioning across all N addition levels,reflecting conservative resource allocation strategies that support long-term ecosystem resilience in nutrient-poor environments.Taken together,these findings deepen our understanding of how nutrient enrichment influences biomass allocation and ecosystem dynamics across different plant life forms,offering practical implications for the management and restoration of degraded sandy ecosystems. 展开更多
关键词 N addition biomass accumulation biomass partitioning fraction allometric relationship plant life form sandy ecosystems Horqin Sandy Land
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福建省城市绿地入侵植物物种多样性及分布格局 被引量:1
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作者 林松昆 叶宝鉴 +2 位作者 常梦琳 付新闻 陈世品 《生物学杂志》 北大核心 2025年第4期88-92,100,共6页
为了查清福建省城市绿地入侵植物的种类和分布状况,对福建省9个市区的42个县级建成区绿地开展入侵植物调查,并分析其物种组成、区系特征、生活型、原产地及入侵危害程度。结果表明,福建省共计有入侵植物130种,隶属于38科89属,其中,菊科(... 为了查清福建省城市绿地入侵植物的种类和分布状况,对福建省9个市区的42个县级建成区绿地开展入侵植物调查,并分析其物种组成、区系特征、生活型、原产地及入侵危害程度。结果表明,福建省共计有入侵植物130种,隶属于38科89属,其中,菊科(Asteraceae)物种数量最多,共31种(占总种数的23.85%);生活型以草本植物为主,共117种(占90.00%);原产地以美洲为主,共97种(占67.83%);入侵植物在科属地理成分上均表现出显著的热带性质;重度威胁类32种(占24.62%),中度危险类29种(占22.31%);沿海福州、莆田、宁德、泉州、漳州和厦门等6市入侵植物共117种,内陆南平、三明、龙岩等3市共97种,两者物种相似系数达0.58。 展开更多
关键词 入侵植物 城市绿地 植物区系 生活型 分布格局
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坡向对高寒草甸植被特征和群落构建的影响 被引量:1
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作者 郭倩 王博 +4 位作者 王平芳 樊勇明 卢培培 张魁 王喜龙 《草业科学》 北大核心 2025年第5期1152-1161,共10页
在局域尺度上,坡向变化引起微环境异质性,从而影响植物群落构建过程、群落结构和物种多样性。通过对青藏高原东缘高寒草甸阴坡和阳坡的植被调查,探讨了坡向对高寒草甸植被特征(功能群、物种多样性和群落组成)和群落构建的影响。结果表明... 在局域尺度上,坡向变化引起微环境异质性,从而影响植物群落构建过程、群落结构和物种多样性。通过对青藏高原东缘高寒草甸阴坡和阳坡的植被调查,探讨了坡向对高寒草甸植被特征(功能群、物种多样性和群落组成)和群落构建的影响。结果表明:1)该地植物以杂类草、直立型和地面芽植物为主。杂类草、莲座型、匍匐型、地上芽和一/二年生植物的物种数比例均表现为阴坡<阳坡(P<0.05),菊科、直立型、丛生型、地面芽和地下芽植物的物种数比例均表现为阴坡>阳坡(P<0.05);2)物种多样性表现为阴坡>阳坡(P<0.01);3)坡向显著影响植物群落组成(P=0.001),相似性百分比分析表明坡向对植物群落组成差异的解释比例超过40%;4)Raup-Crick相异指数表明阴坡植物群落构建主要由随机过程驱动,而阳坡植物群落构建主要受到确定性过程影响。上述结果为当地高寒草甸管理和利用提供了理论依据。 展开更多
关键词 功能群 植物群落组成 物种多样性 生活型 生长型 随机过程 确定性过程
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北京东北部山区不同生活型木本植物叶功能性状特征及其权衡关系
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作者 郭文俊 李鑫豪 +8 位作者 田赟 孙艳丽 房新民 代远萌 陈文婧 李廷山 刘鹏 贾昕 查天山 《林业科学》 北大核心 2025年第9期70-80,共11页
【目的】探究北京东北部山区不同生活型木本植物的叶功能性状及其性状组合,以系统分析该区域内优势木本植物的生态策略差异,为阐明不同生活型木本植物的环境适应机制提供参考。【方法】选取北京东北部山区19个典型木本植物群落中的20种... 【目的】探究北京东北部山区不同生活型木本植物的叶功能性状及其性状组合,以系统分析该区域内优势木本植物的生态策略差异,为阐明不同生活型木本植物的环境适应机制提供参考。【方法】选取北京东北部山区19个典型木本植物群落中的20种优势木本植物,通过野外调查和理化分析相结合的方法,基于植物生活型分类,系统分析灌木、落叶阔叶乔木和针叶乔木3种生活型木本植物的12个典型叶功能性状特征及其关系,分析各生活型间木本植物的权衡策略。【结果】1)针叶乔木的叶面积(LA)、比叶面积(SLA)、叶氮含量(LNC)和叶磷含量(LPC)显著小于落叶阔叶乔木和灌木,叶厚(LT)、叶碳含量(LCC)、碳氮比(C∶N)和碳磷比(C∶P)显著大于落叶阔叶乔木和灌木,表明针叶乔木叶片的构建成本和氮、磷利用效率较高。2)20种优势木本植物的SLA与叶干物质含量(LDMC)呈负相关关系,LNC与LPC呈正相关关系,表明叶片在生长繁殖和增强防御能力间呈权衡关系,且氮、磷元素协同促进植物生长,植物在相似生境中对氮、磷元素的需求不随生活型产生特异性变化。3)LT与LDMC在落叶阔叶乔木间呈极显著正相关关系,在针叶乔木间呈显著负相关关系,而在灌木间不相关。这主要是因为落叶阔叶乔木较厚的叶片通常需要较大的LDMC提供物理结构支撑;而针叶乔木的针形叶虽然较厚,但其叶片中营养物质含量较少且气孔开放程度和水分散发量偏低,导致其LDMC较低。4)通过主成分分析和置换多元方差分析发现,不同生活型木本植物在化学性状轴和结构性状轴间均呈极显著差异(P<0.01),前两轴解释率为63.84%。这表明灌木倾向于高LNC、LPC,低LCC的性状组合,针叶乔木倾向于低LNC、LPC与高LCC的性状组合,而落叶阔叶乔木则沿着更大LA、LDMC以及更小LT的方向变化。【结论】不同生活型木本植物的部分叶功能性状存在显著差异,灌木和落叶阔叶乔木叶片倾向于“快速投资-收益型”策略,针叶乔木叶片倾向于“缓慢投资-收益型”策略。研究结果可为该区域植物资源获取-适应策略及生物多样性保护提供基础数据。 展开更多
关键词 叶功能性状 生活型 叶经济谱 权衡策略 木本植物
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短视频使用对农村中老年人生活满意度的影响机制探究 被引量:2
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作者 陆杰华 张宇昕 李偲廷 《人口与发展》 北大核心 2025年第1期127-138,149,共13页
在信息化与老龄化交汇的时代背景下,互联网不断深入中老年人的日常生活。其中,短视频以便捷娱乐的鲜明特点得到了迅速推广,尤其深受中老年人的喜爱。然而,以短视频为代表的互联网技术产品,一方面无差别地对所有人开放,另一方面也可能加... 在信息化与老龄化交汇的时代背景下,互联网不断深入中老年人的日常生活。其中,短视频以便捷娱乐的鲜明特点得到了迅速推广,尤其深受中老年人的喜爱。然而,以短视频为代表的互联网技术产品,一方面无差别地对所有人开放,另一方面也可能加剧原有的不平等结构。因此,研究旨在探究短视频使用对农村中老年人生活满意度的影响,以及该影响的群体差异与作用机制。基于2023年全国代表性农村地区中老年人短视频使用抽样调查,研究主要采用OLS回归模型分析了短视频使用频率对农村中老年人生活满意度的影响及其群体差异,并进一步考察了社会联结的中介效应和孤独感的门槛效应。研究发现,短视频使用对农村中老年人的生活满意度有着显著的正向影响,短视频使用频率越高,其生活满意度也越高。分群体来看,这种影响在中年群体和中老年女性中更为显著,但在老年群体和中老年男性中却不具有统计显著性。就作用机制来看,社会联结而非社会网络发挥了部分中介效应。就作用条件来看,家庭子女数和孤独感知度分别发挥了单一门槛效应。可以预见,推广以短视频为代表的互联网技术产品使用,将成为数字时代实现积极老龄化的必经之路。 展开更多
关键词 短视频 生活满意度 社会联结 孤独感
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白音敖包国家级自然保护区典型乔、灌木叶、枝及细根生态化学计量特征
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作者 杨昕瑜 张硕 +3 位作者 张曦文 郑青山 苏日力格 谷加存 《植物研究》 北大核心 2025年第5期795-806,共12页
为揭示半干旱地区木本植物的养分限制因子与养分利用策略,研究了内蒙古白音敖包国家级自然保护区6种典型木本植物(乔木和灌木各3种)叶、枝、吸收根和运输根碳(C)、氮(N)、磷(P)化学计量特征的差异和相关性。结果表明:6种木本植物叶平均C... 为揭示半干旱地区木本植物的养分限制因子与养分利用策略,研究了内蒙古白音敖包国家级自然保护区6种典型木本植物(乔木和灌木各3种)叶、枝、吸收根和运输根碳(C)、氮(N)、磷(P)化学计量特征的差异和相关性。结果表明:6种木本植物叶平均C/N(质量比)和C/P(质量比)显著低于枝、吸收根和运输根,而吸收根平均N/P(质量比)则显著高于叶、枝和运输根(P<0.05)。乔木叶和枝平均C含量显著高于灌木,而吸收根和运输根C含量显著低于灌木(P<0.05)。乔木叶平均C/N(22.45)、C/P(291.04)分别高于灌木叶C/N(16.16)、C/P(153.70),乔木枝、吸收根和运输根平均C/N(43.84、24.56和43.56)与C/P(369.27、555.20和800.79)则分别低于灌木(C/N为61.97、32.31和52.69;C/P为542.75、725.56和813.76)。乔木仅叶平均N/P(14.12)显著高于灌木(9.53)(P<0.05)。叶C含量与枝C、P含量极显著正相关(P<0.01),吸收根与运输根N、P、C/N和C/P间显著正相关(P<0.05),而地上与地下器官间的相关性相对较弱。综上,乔木叶表现出较高的养分利用效率,而灌木地下器官则具有更高的养分利用效率,叶和枝在C分配上、吸收根和运输根在N、P分配及利用上均表现出协同关系。 展开更多
关键词 生态化学计量学 器官 生活型 沙地云杉 半干旱森林生态系统
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林下植被叶际微生物群落对生活型与光照的响应
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作者 张子璇 孟晓倩 +4 位作者 张新娜 徐程扬 陈涛 王文学 宁秋玲 《北京林业大学学报》 北大核心 2025年第9期67-79,共13页
【目的】叶际微生物群落对森林生态系统稳定性和植物健康具有重要影响。本研究旨在揭示光照和植物生活型对林下植被叶际微生物群落的影响,为城市森林生态管理及生态系统稳定性维持提供理论支撑。【方法】以北京西山国家森林公园油松人... 【目的】叶际微生物群落对森林生态系统稳定性和植物健康具有重要影响。本研究旨在揭示光照和植物生活型对林下植被叶际微生物群落的影响,为城市森林生态管理及生态系统稳定性维持提供理论支撑。【方法】以北京西山国家森林公园油松人工林下典型灌木和草本植物为研究对象,以光合有效辐射为指标,设置低(<500μmol/(m^(2)·s))、中(500~1000μmol/(m^(2)·s))和高(>1000μmol/(m^(2)·s))3个光照梯度,基于高通量测序技术,分析叶际细菌与真菌群落的多样性、组成结构及扩增子序列变体(ASV)特异性响应特征。【结果】(1)光照强度对细菌和真菌群落α多样性影响不显著,而植物生活型对群落多样性和结构具有显著影响,特别是在真菌群落中更为突出。草本植物真菌群落的Chao1、Observed_species和Good's_coverage指数均显著高于灌木(p<0.05),PERMANOVA分析表明,生活型对细菌和真菌群落变异的解释率分别约为3.83%和3.70%(p<0.001)。(2)群落结构分析表明,细菌群落主要由变形菌门主导,优势属分布稳定;而真菌群落在属水平随光照和植物类型变化明显,低光下以茎点球属为主,中高光下以横断孢属为主。PCoA与PERMANOVA结果进一步验证生活型对群落结构影响显著(p<0.001),而光照影响不显著。(3)ASV分析表明,不同生活型和植物物种间存在较高特异性,真菌群落中灌木与草本共有ASV仅占18.6%,而细菌为11.47%;在植物物种水平,ASV多为物种特有类型,不同植物间共享的ASV极少,表现出较强的宿主专一性。【结论】植物生活型是影响林下植被叶际微生物群落结构的关键因子,其调控效应显著高于光照,且真菌群落对植物宿主属性和环境变化的敏感性更高。研究揭示了植物生活型在微生物群落构建过程中的生态作用,为基于微生物生态的城市森林植物配置策略提供了新视角。 展开更多
关键词 叶际微生物 林下植被 生活型 光照强度 城市森林
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基于天然草地12种根茎禾草种群构件年龄结构与衰老过程的趋同适应普遍模式
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作者 韩大勇 杨允菲 +1 位作者 李海燕 张维 《草业学报》 北大核心 2025年第11期217-226,共10页
根茎禾草是典型的无性系植物,其生活型为地下芽植物,也是北方草原广泛分布的优势植物。将多种根茎禾草研究的零散报道加以集成,从其共同特征中寻找普遍模式,揭示同一生活型植物趋同适应的生物学与生态学机理及进化意义。在近30年相关研... 根茎禾草是典型的无性系植物,其生活型为地下芽植物,也是北方草原广泛分布的优势植物。将多种根茎禾草研究的零散报道加以集成,从其共同特征中寻找普遍模式,揭示同一生活型植物趋同适应的生物学与生态学机理及进化意义。在近30年相关研究成果中,选用具代表性并且数据丰富的12种根茎禾草,每种均选用放牧场、割草场和围栏封育草地3种利用方式,进行了种群构件年龄结构与衰老过程的比较与理论分析。主要发现包括:1)所有12种根茎禾草构件的寿命均具有限性,分蘖节最多可繁殖4个世代,最长寿命为5年,根茎的最长寿命为4年;2)3种构件(分蘖株、根茎和芽)的数量除了个别放牧场为稳定型年龄结构外,其余均为增长型年龄结构;3)分蘖节大多从2龄级开始迅速衰老,根茎的衰老过程相对缓慢。根茎禾草在趋同适应过程中所形成的以根茎芽补充更新1龄级分蘖株的繁殖方式,具有两个进化意义:对于个体,成功地实现了种子实生苗一旦定居,其基株基因便长寿乃至永生的进化极致;对于种群,不仅维持了构件的增长型年龄结构,也扩展了生长空间,减少了根茎芽形成的分蘖株与亲株分蘖节芽形成的不同龄级分蘖株之间的竞争。这些适应对种群的生存与发展具有重要的进化意义。 展开更多
关键词 生活型 无性系植物 营养繁殖 构件 年龄谱 分蘖株生产力 根茎贮藏力
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