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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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蓝果树在福建省的分布格局生境偏好与保护策略研究
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作者 黄华明 黄淑燕 +1 位作者 甘振栋 季恭国 《农业与技术》 2026年第1期84-89,共6页
蓝果树(Nyssa sinensis)是中国特有的珍稀树种,主要分布在长江以南地区,不仅具有重要的生态和观赏价值,同时蓝果树富含萜类化合物、黄酮类化合物、鞣质等生物活性物质,具有很高的药用潜在开发价值。本研究基于福建省森林种质资源普查数... 蓝果树(Nyssa sinensis)是中国特有的珍稀树种,主要分布在长江以南地区,不仅具有重要的生态和观赏价值,同时蓝果树富含萜类化合物、黄酮类化合物、鞣质等生物活性物质,具有很高的药用潜在开发价值。本研究基于福建省森林种质资源普查数据,分析了蓝果树的种群分布特征、生长习性及环境适应性。结果显示,蓝果树在福建省主要分布于海拔290~1310m的山区,以散生或零星方式存在,生活型以乔木为主(占比约70%),灌木为辅(30%)。其分布与海拔、地形及水源涵养区密切相关。本文建议通过加强栖息地保护和人工繁育等措施,促进蓝果树种群提升和资源的可持续利用。 展开更多
关键词 蓝果树 种群 生活型
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明清徽州女性传记的量化分析与礼教规训机制研究
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作者 赵静 《佳木斯大学社会科学学报》 2026年第3期114-118,共5页
通过对封建礼教规训下女性社会角色典型性的提炼,挑选明清时期徽州女性人物传记中的节妇、烈女、徽商妇、才媛四类女性,按守节特点、殉葬动机、经济行为、德才互构等归类,对传记的叙事模式进行量化分析和质性研究,揭示宗族伦理规范如何... 通过对封建礼教规训下女性社会角色典型性的提炼,挑选明清时期徽州女性人物传记中的节妇、烈女、徽商妇、才媛四类女性,按守节特点、殉葬动机、经济行为、德才互构等归类,对传记的叙事模式进行量化分析和质性研究,揭示宗族伦理规范如何被利用为封建礼教的控制工具;通过文本的隐含语义、感情倾向捕捉徽州女性群体与当时社会规训机制的复杂博弈,展现女性个体的生命形态,揭示明清徽州女性独特的生存现象与意识形态、社会结构的复杂关联,提供一个透视徽州社会价值观与女性地位的独特窗口。 展开更多
关键词 徽州女性 宗族伦理 社会规训 生命形态
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西藏亚高山森林土壤种子库与地上植被群落的海拔梯度分异特征
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作者 邓炜展 张艳 +5 位作者 王彬 袁旭 彭李 冀晓东 周金星 张喆 《北京林业大学学报》 北大核心 2026年第1期119-128,共10页
【目的】土壤种子库是植被群落更新与演替的潜在种源储备,研究亚高山森林生态系统中土壤种子库的分布特征及其与地上植被的关联,有助于评估生态系统的自然恢复潜力,为群落重建与生态修复实践提供科学依据。【方法】以西藏林芝市巴宜区海... 【目的】土壤种子库是植被群落更新与演替的潜在种源储备,研究亚高山森林生态系统中土壤种子库的分布特征及其与地上植被的关联,有助于评估生态系统的自然恢复潜力,为群落重建与生态修复实践提供科学依据。【方法】以西藏林芝市巴宜区海拔2300~3300 m的亚高山森林区为研究对象,采用样方法进行地上植被调查与土壤采样,并通过萌发法分析土壤种子库的物种组成、生活型构成及密度分布特征。【结果】(1)土壤种子库中共萌发30种植物,分属15科27属,主要为一年生或多年生草本植物,物种组成较地上植被群落更为单一。(2)随着海拔升高,土壤种子库与地上植被的物种丰富度均呈现“先增后降”的趋势,多年生草本植物比例增加,表现出对高海拔环境的较强适应性。(3)Margalef丰富度指数、Shannon多样性指数和Simpson多样性指数随海拔升高呈现先升后降的趋势。不同海拔高度的土壤种子库与地上植被的Sørensen相似性指数较低(0.240~0.375),并随海拔升高呈下降趋势。(4)地上植被密度与土壤种子密度呈显著正相关关系(r=0.721,P<0.01)。土壤种子密度随海拔升高呈现先增大后减小的趋势,变化范围为(47.22±2.78)粒/m^(2)~(141.67±13.89)粒/m^(2),其垂直分布具有递减趋势,表现出明显的表层(0~10 cm)富集特征。【结论】亚高山森林土壤种子库与地上植被在物种丰富度和生活型上差异显著,种子密度较低且木本成分匮乏,自然恢复能力有限。建议通过人工构建乡土物种种子库以促进生态修复。本研究为亚高山森林恢复潜力评估与修复策略制定提供了科学依据。 展开更多
关键词 海拔梯度 土壤种子库 生活型 相似性指数 西藏
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不同生活型和气孔分布类型植物叶片气孔特征差异及其与叶资源经济性状关联
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作者 刘禹含 李婷婷 +3 位作者 杨柳 李特 刘刚 王秀伟 《植物研究》 北大核心 2026年第1期131-144,共14页
为探究不同生活型(乔木、灌木)和气孔分布类型(单面气孔型、双面气孔型)植物气孔特征差异及其与叶资源经济性状的相关关系,该研究于2023年7—8月以东北林业大学校园内常见的22个树种为研究对象,通过相关分析和标准化主轴分析发现:(1)生... 为探究不同生活型(乔木、灌木)和气孔分布类型(单面气孔型、双面气孔型)植物气孔特征差异及其与叶资源经济性状的相关关系,该研究于2023年7—8月以东北林业大学校园内常见的22个树种为研究对象,通过相关分析和标准化主轴分析发现:(1)生活型和气孔分布类型都显著影响气孔特征,乔木的气孔密度(D_(S))显著高于灌木(P<0.05),而气孔开度(A_(S))较低;单面气孔型植物的D_(S)和气孔相对面积(A_(SR))显著高于双面气孔型植物(P<0.05);(2)气孔特征之间的关系在不同的生活型和气孔分布类型中存在差异,D_(S)与气孔大小(S_(S))和A_(SR)呈负相关关系,且仅在乔木和单面气孔型植物中达到显著水平(P<0.05);S_(S)和A_(S)呈正相关关系,且仅在单面气孔型植物中达到显著水平(P<0.05);(3)气孔特征与其他叶资源经济性状关系紧密,D_(S)和A_(SR)都与比叶面积(A_(S)L)和叶片氮含量(N_(L))负相关,与干物质含量(C_(LDM))正相关(P<0.05),A_(S)与N_(L)负相关。叶片性状间的协同关系在乔木和单面气孔型植物中更加稳定,而在灌木和双面气孔型植物中更趋向于独立发展。研究结果有助于进一步了解不同类别植物的气孔发育策略。 展开更多
关键词 生活型 双面气孔型 气孔特征 叶资源经济性状
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中国岛屿特有植物油叶柯群落特征与物种多样性分析
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作者 林新豪 傅可怡 +5 位作者 杨芝来 张世泓 丁明艳 马少伟 冯欣欣 施诗 《植物资源与环境学报》 北大核心 2026年第1期83-92,共10页
为探究呈岛屿间断分布的中国特有种油叶柯〔Lithocarpus konishii(Hayata)Hayata〕的群落结构、区系特征及多样性,在其分布区广东担杆岛、香港及海南文昌设置13个典型样地(总面积5800 m 2)并开展群落学调查,分析其群落的物种组成、结构... 为探究呈岛屿间断分布的中国特有种油叶柯〔Lithocarpus konishii(Hayata)Hayata〕的群落结构、区系特征及多样性,在其分布区广东担杆岛、香港及海南文昌设置13个典型样地(总面积5800 m 2)并开展群落学调查,分析其群落的物种组成、结构特征、区系特征、物种多样性及类型。结果表明:13个油叶柯样地物种组成丰富,共有维管植物200种(含种下等级,下同),隶属于74科162属,其中海南文昌样地的物种数(140种)远多于香港和广东担杆岛样地。从生活型看,13个油叶柯样地中乔木、灌木、草本和藤本分别有41、85、57和17种,占比分别为20.5%、42.5%、28.5%和8.5%。从地理成分看,13个油叶柯样地植物群落在科和属水平均以泛热带和热带亚洲分布为主,热带性质明显。多样性分析结果显示:油叶柯样地灌木层的物种多样性指数总体高于乔木层和草本层。基于乔木层重要值的聚类分析结果,13个油叶柯样地的植物群落划分为油叶柯+鹅掌柴林〔Form.L.konishii+Heptapleurum heptaphyllum(Linn.)Y.F.Deng〕、台湾相思+油叶柯林(Form.Acacia confusa Merr.+L.konishii)、油叶柯+文昌锥林(Form.L.konishii+Castanopsis wenchangensis G.A.Fu et C.C.Huang)3类,与地理分布相吻合。综上所述,油叶柯群落为具热带特性的常绿阔叶林,但因处于次生演替不稳定阶段,亟需制定针对性保护策略以维持生态系统稳态。 展开更多
关键词 油叶柯 物种组成 生活型 群落类型 物种多样性
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“具身智能体”下的“类生命”:属性、挑战与应对
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作者 刘瑞雪 李振 《长沙理工大学学报(社会科学版)》 2026年第1期53-60,共8页
具身智能体是对人类认知与行动能力的智能化模仿、延伸和创新,其实质是智能时代人类“类本质”力量在技术客体中的对象化呈现。具身智能体在拓展人类生命活动广度和深度的同时,因物质实体与智能算法的融合催生了新的“类生命”反思。在... 具身智能体是对人类认知与行动能力的智能化模仿、延伸和创新,其实质是智能时代人类“类本质”力量在技术客体中的对象化呈现。具身智能体在拓展人类生命活动广度和深度的同时,因物质实体与智能算法的融合催生了新的“类生命”反思。在“人类世”语境下,人类与智能机器“具身”生成硅基生命体,威胁人类生命的“唯一性”;强算法主导的认知替代容易引发生命责任弥散。为此,必须从回到人本身、警惕工具属性僭越、规范责任框架三个方面重构人机辩证关系,在“以人为本、人机共生”原则下释放技术潜能,维系人类生命核心价值。 展开更多
关键词 具身智能体 类生命 人机共生 硅基生命体
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浙江省开化县重点湿地维管植物区系分析
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作者 李红 刘益晨 +5 位作者 段润 王毅 任闻达 李欣竹 张现武 李伟成 《安徽农业科学》 2026年第2期106-110,125,共6页
为合理开发利用和保护植物资源,调查了浙江省开化县重点湿地区域维管植物资源并进行植物区系分析。结果发现:该区域共有野生维管植物362种,隶属于93科242属。科、属的组成以单种科(单种属)和小型科(小型属)占优势。生活类型以草本植物为... 为合理开发利用和保护植物资源,调查了浙江省开化县重点湿地区域维管植物资源并进行植物区系分析。结果发现:该区域共有野生维管植物362种,隶属于93科242属。科、属的组成以单种科(单种属)和小型科(小型属)占优势。生活类型以草本植物为主,占物种总数的74.31%。科、属的分布区类型多样,除世界广布型外,以热带分布成分为主,温带分布次之,呈现从热带向温带过渡的趋势。植物区系起源古老,保留着多种系统演化上原始的科、属及古老的孑遗植物。 展开更多
关键词 区系分布 物种组成 湿地 生活型 野生植物
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瑞丽市园林绿地园林植物资源调查与分析
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作者 段秀明 罗仁山 +3 位作者 岳正奎 蔡薇 张天谣 杨飞 《林业调查规划》 2026年第1期111-117,共7页
基于云南省德宏州城乡园林绿化提升行动,对瑞丽市公园绿地、广场绿地、道路绿地、单位附属绿地、居住区绿地共23个园林绿地进行实地调查,分析其园林植物组成、生活型、观赏特性、应用频率、本地木本植物指数。结果表明,瑞丽市共有园林植... 基于云南省德宏州城乡园林绿化提升行动,对瑞丽市公园绿地、广场绿地、道路绿地、单位附属绿地、居住区绿地共23个园林绿地进行实地调查,分析其园林植物组成、生活型、观赏特性、应用频率、本地木本植物指数。结果表明,瑞丽市共有园林植物113科311属455种;乔木、灌木、草本、藤本种类比例为22.40∶12.00∶10.10∶1.00;常绿与落叶植物比例为2.56∶1.00;观赏特性排名为:观叶植物>观花植物>观果植物>观茎植物;园林植物应用频率为:乔木植物>灌木植物>草本植物,其中应用频率最高的是三角梅和红花檵木;本地木本植物共322种,植物指数为0.91。瑞丽市园林绿地园林植物选择不够丰富,植物景观略显单一;部分植物不适应本地气候,景观效果不佳。提出提高园林绿地园林植物多样性和乡土树种应用比例,提升区域景观特色,提高园林植物养护管理水平等建议。 展开更多
关键词 园林植物 资源调查 生活型 观赏特性 应用频率 植物指数 瑞丽市
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寿命与成形性能的完美结合——PrintForm HR成形网 被引量:4
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作者 Carl J Taylor 《中华纸业》 CAS 北大核心 2007年第9期36-38,共3页
介绍了福伊特造纸织物最新开发的新产品——PrintForm HR成形网,重点论述了这一产品的经线/纬线组合、纬线结构,以及使用效果。这种成形网采用SSB技术和8梭口反面结构,与常规结构相比,可以延长成形网的使用寿命、提高脱水能力并增强横... 介绍了福伊特造纸织物最新开发的新产品——PrintForm HR成形网,重点论述了这一产品的经线/纬线组合、纬线结构,以及使用效果。这种成形网采用SSB技术和8梭口反面结构,与常规结构相比,可以延长成形网的使用寿命、提高脱水能力并增强横向挺度。对于采用高填料含量且纸页质量和留着率要求较高的纸机,这种耐用的成形网效果明显。 展开更多
关键词 经线/纬线组合 纬线结构 SSB技术 性能 寿命 成形网 福伊特织物
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Evolution from Primitive Life to Homo sapiens Based on Visible Genome Structures: The Amino Acid World 被引量:3
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作者 Kenji Sorimachi 《Natural Science》 2009年第2期107-119,共13页
It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of r... It is not too much to say that molecular biology, including genome research, has progressed based on the determination of nucleotide or amino acid sequences. However, these ap-proaches are limited to the analysis of relatively small numbers of the same genes among spe-cies. On the other hand, by graphical presenta-tion of the ratios of the numbers of amino acids present to the total numbers of amino acids presumed from the target gene(s) or genome or those of the numbers of nucleotides present to the total numbers of nucleotides calculated from the target gene(s) or genome, we can readily draw conclusions from extraordinarily huge data sets integrated by human intelli-gence. 1) Assuming polymerization of amino acids or nucleotides in a simulation analysis based on a random choice, proteins were formed by simple amino acid polymerization, while nucleotide polymerization to form nucleic acids encoding specific proteins needed certain specific control. These results proposed that protein formation chronologically preceded codon formation during the establishment of primitive life forms. In the prebiotic phase, amino acid composition was a dominant factor that determined protein characteristics;the “Amino Acid World”. 2) The genome is constructed homogeneou- sly from putative small units displaying similar codon usages and coding for similar amino acid compositions;the unit is a gene assembly en-coding 3,000 - 7,000 amino acid residues and this unit size is independent not only of genome size, but also of species. 3) In codon evolution, all nucleotide alterna-tions are correlated, not only in coding regions, but also in non-coding regions;the correlations can be expressed by linear formulas;y = ax + b, where “y” and “x” represent nucleotide con-tents, and “a” and “b” are constant. 4) The basic pattern of cellular amino acid compositions obtained from whole cell lysates is conserved from bacteria to Homo sapiens, and resembles that calculated from complete genomes. This basic pattern is characterized by a “star-shape” that changes slightly among species, and changes in amino acid composi-tion seem to reflect biological evolution. 5) Organisms can essentially be classified according to two codon patterns. Biological evolution due to nucleotide sub-stitutions can be expressed by simple linear formulas based on mathematical principles, while natural selection must affect species pre- servation after nucleotide alternations. There-fore, although Darwin’s natural selection is not directly involved in nucleotide alternations, it contributes obviously to the selection of nu-cleotide alternations. Thus, Darwin’s natural selection is doubtless an important factor in biological evolution. 展开更多
关键词 EVOLUTION PRIMITIVE life form Genome NUCLEOTIDE Content Chargaff’s PARITY Rules CODON Amino Acids Linear formula Classification
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Predictors of Chronic Physical and Mental Quality of Life Following Traumatic Brain Injury
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作者 Shahrokh Yousefzade-Chabok Sara Ramezani Kapourchali +3 位作者 Zoheir Reihanian Ehsan Kazemnezhad Leili Anoush Dehnadi Moghadam Zahra Mohtasham Amiri 《Health》 2014年第6期496-503,共8页
Objective and Background: This study aimed at determining the predictors of chronic physical and mental quality of life (QOL) in patients with traumatic brain injury (TBI) focusing on neuropsychological functions post... Objective and Background: This study aimed at determining the predictors of chronic physical and mental quality of life (QOL) in patients with traumatic brain injury (TBI) focusing on neuropsychological functions post trauma. Materials and Methods: This is a longitudinal study in which 257 patients having inclusion criteria were enrolled. Neuropsychological tasks including logical memory, verbal paired associates, visual memory, verbal expression, auditory comprehension, semantic judgment and semantic categories were implemented. The appearance of psychiatric disorder, Agnosia, Apraxia, Dysarthria and pragmatic linguistic disorder post trauma were evaluated at discharge. QOL was studied 6 months after injury by filling SF-36 questionnaire via phone interview with patients. Results: Appearance of some post-traumatic disorders including agnosia, pragmatic linguistic disorder and psychiatric disorder were significantly correlated to poor QOL. The final step of logistic regression model showed that TBI severity, verbal memory, auditory comprehension and semantic acceptability scores were predictors of unfavorable mental QOL as well as TBI severity, injury severity scale (ISS) score and multifocal lesions for unfavorable physical QOL. Discussion: Thus, it is recommended that clinicians choose medical therapeutic priorities to improve the verbal neuropsychological sequela and provide preliminaries for a chronic favorable mental QOL. Furthermore, to prevent of chronic unfavorable physical QOL, early care of organic injuries should be considered especially in patients with severe and multifocal TBI. 展开更多
关键词 TRAUMATIC Brain Injury Physical and MENTAL Quality of life Short form-36 QUESTIONNAIRE NEUROPSYCHOLOGICAL Functions
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