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A FORM FUNCTION METHOD FOR FORM FINDING OF TENSION STRUCTURE
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作者 孙宗光 赵俭斌 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第11期1277-1281,共5页
A new form function involving parameters Pi is presented. On the basis of the form function, an initial form of tension structure was Sound by interpolating through the control points on boundary of the structure. The... A new form function involving parameters Pi is presented. On the basis of the form function, an initial form of tension structure was Sound by interpolating through the control points on boundary of the structure. The form function can be controlled by changing beta (1) according to the pre-tension and the boundary of the structure. The final form of a tension structure should be an equilibrium system under the pretension. To examine the nature of the initial form, the FEM was used. Many examples show that the initial form gives a very ideal result for equal or unequal pre-tension in two directions of the structure. In general cases, there is little difference between the initial form and the final one. 展开更多
关键词 tension structure form finding form function
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Multi-group pin power reconstruction method based on colorset form functions 被引量:1
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作者 HUANG Hao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第1期60-64,共5页
A multi-group pin power reconstruction method that fully exploits nodal information obtained from global coarse mesh solution has been developed.It expands the intra-nodal flux distributions into nonseparable semi-ana... A multi-group pin power reconstruction method that fully exploits nodal information obtained from global coarse mesh solution has been developed.It expands the intra-nodal flux distributions into nonseparable semi-analytic basis functions,and a colorset based form function generating method is proposed,which can accurately model the spectral interaction occurring at assembly interface.To demonstrate its accuracy and applicability to realistic problems, the new method is tested against two benchmark problems,including a mixed-oxide fuel problem.The results show that the new method is comparable in accuracy to fine-mesh methods. 展开更多
关键词 群组管理 LWR 二维多群辐射 输运过程 原子核
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A two-grid algorithm based on Newton iteration for the stream function form of the Navier-Stokes equations 被引量:1
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作者 SHAO Xin-ping HAN Dan-fu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第3期368-378,共11页
In this paper, we propose a two-grid algorithm for solving the stream function formulation of the stationary Navies-Stokes equations. The algorithm is constructed by reducing the original system to one small, nonlinea... In this paper, we propose a two-grid algorithm for solving the stream function formulation of the stationary Navies-Stokes equations. The algorithm is constructed by reducing the original system to one small, nonlinear system on the coarse mesh space and two similar linear systems (with same stiffness matrix but different right-hand side) on the fine mesh space. The convergence analysis and error estimation of the algorithm are given for the case of conforming elements. Furthermore, the Mgorithm produces a numerical solution with the optimal asymptotic H^2-error. Finally, we give a numerical illustration to demonstrate the effectiveness of the two-grid algorithm for solving the Navier-Stokes equations. 展开更多
关键词 Two-grid algorithm Navier-Stokes equations Stream function form Reynolds number Newton iteration.
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A modeling approach for fuzzy programming with echelon form membership functions
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作者 WEN Bo LI HongGuang CHEN XiaoChun 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第1期78-83,共6页
In order to solve fuzzy mathematical programming with soft constraints,the initial models must first be converted into crisp models.Membership functions are employed to describe the fuzzy right-hand side parameters ne... In order to solve fuzzy mathematical programming with soft constraints,the initial models must first be converted into crisp models.Membership functions are employed to describe the fuzzy right-hand side parameters needed to achieve this conversion.In some cases,echelon form membership functions(EFMFs)are required to depict the actual fuzzy situation.However,due to their discrete properties,fuzzy programming problems with such membership functions cannot be modeled by traditional methods.Motivated by these challenges,this paper introduces a novel absolute value representation modeling approach to formulate fuzzy programming using EFMFs.This approach can translate a discrete model to a continuous one which can then be easily solved.Finally,by means of a numerical example,the effectiveness of our new approach is demonstrated. 展开更多
关键词 echelon form membership function fuzzy right-hand side absolute value representation
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Form and Function——An Overview
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作者 李艳 《海外英语》 2012年第18期228-229,共2页
Long before,the research of form has already entered its heyday,but the study of function is a somewhat new branch of language study.This essay is an attempt to take a brief look at the most significant distinction be... Long before,the research of form has already entered its heyday,but the study of function is a somewhat new branch of language study.This essay is an attempt to take a brief look at the most significant distinction between"form and function",and then aims at making clear the definition of"form and function"in discourse analysis. 展开更多
关键词 form function DISCOURSE ANALYSIS
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RESIDUAL A POSTERIORI ERROR ESTIMATE TWO-GRID METHODS FOR THE STEADY (NAVIER-STOKES) EQUATION WITH STREAM FUNCTION FORM
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作者 任春风 马逸尘 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第5期546-559,共14页
Residual based on a posteriori error estimates for conforming finite element solutions of incompressible Navier-Stokes equations with stream function form which were computed with seven recently proposed two-level met... Residual based on a posteriori error estimates for conforming finite element solutions of incompressible Navier-Stokes equations with stream function form which were computed with seven recently proposed two-level method were derived. The posteriori error estimates contained additional terms in comparison to the error estimates for the solution obtained by the standard finite element method. The importance of these additional terms in the error estimates was investigated by studying their asymptotic behavior. For optimal scaled meshes, these bounds are not of higher order than of convergence of discrete solution. 展开更多
关键词 two-level method Navier-Stokes equation residual a posteriori error estimate finite element method stream function form
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Plasma spray forming of functionally graded materials mould
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作者 赵紫玉 方建成 李洪友 《中国有色金属学会会刊:英文版》 CSCD 2005年第2期427-431,共5页
A new technology of functionally graded materials(FGM) mould fabricated by plasma spraying and arc spraying was developed. According to applied characteristic of plastic mould, the reasonable coatings of FGM were desi... A new technology of functionally graded materials(FGM) mould fabricated by plasma spraying and arc spraying was developed. According to applied characteristic of plastic mould, the reasonable coatings of FGM were designed and their microstructures were analyzed. At the same time, some key problems were solved including spray mould fabricating, FGM forming and demoulding, etc. The results show that the service performance of the FGM mould is much more excellent than the one composed of the traditional materials, and the life span can also be greatly increased. The technology will have a significant influence on materials development in mould industry. 展开更多
关键词 溅射成型 功能分级材料 塑料模具 等离子体
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TRANSFORMATION OF SYMMETRIC MULTIPLICATIVE FUNCTIONALS
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作者 AnHong YingJiangang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第4期451-457,共7页
In the present paper the transformation of symmetric Markov processes by symmetric martingale multiplicative functionals is studied and the corresponding Dirichlet form is formulated.
关键词 Markov processes Dirichlet forms multiplicative functional.
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FORM AND FUNCTION OF EGYPTIAN BREAD MOLDS
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作者 Sheldon Lee Gosline 《Journal of Ancient Civilizations》 1999年第0期27-44,共18页
关键词 VI IV OK form AND function OF EGYPTIAN BREAD MOLDS
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A Sociolinguistic Study of Husband-to-Wife Address Forms and Functions in Rural Jordanian Community
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作者 Awni Shati M. Etaywe 《宏观语言学》 2017年第2期84-117,共34页
关键词 语言学 民族文化 文化传统 语用学
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Grand Zero Density Estimates of L-functions Associated with Cusp Forms
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作者 LI Ying-jie 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期79-86,共8页
In this paper a zero-density estimate of the large sieve type is given for the automorphic L-function L f (s,χ),where f is a holomorphic cusp form and χ a Dirichlet character of mod q.
关键词 zero density L-function cusp form
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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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A NEW METHOD FOR ESTABLISHING PSEUDO ORTHOGONAL PROPERTIES OF EIGENFUNCTION EXPANSION FORM IN FRACTURE MECHANICS
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作者 OuZhuocheng ChenYiheng 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第4期283-289,共7页
A new and simple method is developed to establish the pseudo orthogonal properties (POP) of the eigenfunction expansion form (EEF) of crack-tip stress complex potential functions for cracked anisotropic an... A new and simple method is developed to establish the pseudo orthogonal properties (POP) of the eigenfunction expansion form (EEF) of crack-tip stress complex potential functions for cracked anisotropic and piezoelectric materials, respectively. Di?erent from previous research, the complex argument separation technique is not required so that cumbersome manipulations are avoided. Moreover, it is shown, di?erent from the previous research too, that the orthogonal properties of the material characteristic matrices A and B are no longer necessary in obtaining the POP of EEF in cracked piezoelectric materials. Of the greatest signi?cance is that the method presented in this paper can be widely extended to treat many kinds of problems concerning path- independent integrals with multi-variables. 展开更多
关键词 eigenfunction expansion form pseudo orthogonal properties Bueckner integral weight function piezoelectric material anisotropic material
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大众创作·表现大众·为了大众——关于新大众文艺若干问题的思考
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作者 王光东 《山东社会科学》 北大核心 2026年第1期33-39,共7页
新大众文艺的兴起与互联网技术的发展密切相关,呈现出大众广泛参与、创作主体多样化的“大众创作”的特点,其内容是“表现大众”的生活、表达大众的思想情感,以及彰显新时代的精神风貌。在艺术形式层面,新大众文艺既要自觉地借鉴传统文... 新大众文艺的兴起与互联网技术的发展密切相关,呈现出大众广泛参与、创作主体多样化的“大众创作”的特点,其内容是“表现大众”的生活、表达大众的思想情感,以及彰显新时代的精神风貌。在艺术形式层面,新大众文艺既要自觉地借鉴传统文艺(包括现当代文艺)形式,又要在表现大众生活、思想与情感的实践中探索和创造新的形式,最终确立起通俗易懂、兼具中国风格与中国气派的新大众文艺形态。这种“为了大众”而创作的文艺形态,其根本价值与功能在于满足人民大众日益增长的精神文化需求和审美需要,同时有效传达新时代的文明理念以及人民大众对美好生活的向往。因此,为大众创作的新大众文艺,应重视技术与文艺融合所催生的新兴文艺类型中可能存在的问题,不仅要不断完善和改进技术,而且要进一步提升大众的文化素养和审美水平,从而构建起一种技术与文化共融相伴的良性发展机制。 展开更多
关键词 新大众文艺 创作主体 内容与形式 价值与功能
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天山北坡耕地利用转型时空演变及其驱动因素研究——基于OPGD模型
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作者 马雪梦 阿依吐尔逊·沙木西 赵俊 《资源开发与市场》 2026年第1期54-64,共11页
为优化耕地利用格局,摸清耕地利用的发展态势,为天山北坡地区耕地保护提供依据。从空间与功能形态转型两个视角,运用熵值法、空间自相关与OPGD模型等方法,借助ArcGIS空间表达技术,揭示耕地利用转型的时空演变格局及其驱动因素。结果表明... 为优化耕地利用格局,摸清耕地利用的发展态势,为天山北坡地区耕地保护提供依据。从空间与功能形态转型两个视角,运用熵值法、空间自相关与OPGD模型等方法,借助ArcGIS空间表达技术,揭示耕地利用转型的时空演变格局及其驱动因素。结果表明:①从时空变化看,2000—2020年空间形态转型水平逐渐提高、功能形态转型呈平缓波动趋势,高值区由中部核心城市逐步向边缘城市扩散,综合转型指数呈上涨趋势,耕地利用转型格局形成以中部盆地平原、西部伊犁河谷平原为主的高值区与东部山地低值区并存的空间格局;②从空间集聚特征看,空间形态转型呈先减少后增加最后减少的趋势,于2010年达到峰值,聚集区域由双核逐步向多核发展,功能形态转型呈先升高后再降低最后趋于平缓的态势,聚集区总体位于中部地区;③从驱动因素看,城镇化率、地均固定资产投资与人口密度对耕地利用转型的影响更为突出。综上,天山北坡耕地利用转型结果正逐步向好,但仍存在区域间差异,应利用人口与社会经济因素对转型的驱动作用,促进耕地资源的可持续利用,实现耕地利用优化转型。 展开更多
关键词 耕地利用格局 空间形态 功能形态 驱动因素 OPGD模型 天山北坡
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黄磷生产废水中磷形态解析及分布特征
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作者 左亮 冯晓楠 +6 位作者 黄胜超 许金宝 宋珮瑶 廖良栋 卢仕玉 刘颖 罗凡 《中国给水排水》 北大核心 2026年第5期105-111,共7页
新兴行业的快速发展使得磷资源变得紧缺,同时黄磷生产急需绿色资源化改造,因此考虑对其高浓度磷酸盐生产废水进行磷资源回收。然而目前对黄磷生产废水中的复杂磷形态缺乏系统性的检测手段,资源化回收工作难以开展。为此,以湖北某黄磷企... 新兴行业的快速发展使得磷资源变得紧缺,同时黄磷生产急需绿色资源化改造,因此考虑对其高浓度磷酸盐生产废水进行磷资源回收。然而目前对黄磷生产废水中的复杂磷形态缺乏系统性的检测手段,资源化回收工作难以开展。为此,以湖北某黄磷企业生产废水为例,归纳提出不同磷形态的定性解析和定量检测方法,考察典型黄磷生产工艺不同节点的废水磷形态分布情况,提出不同磷形态转化途径,并基于密度泛函理论计算分析转化机理。结果表明,该解析和检测方法适用于复杂磷形态水样,黄磷生产废水中的磷含量最高可达40 g/L,大多数水样在17 g/L左右,其中约70%为正磷酸盐,具有较高的磷资源回收利用价值,可为黄磷化工行业的资源化提供参考。 展开更多
关键词 黄磷生产废水 磷检测 磷形态 磷回收 密度泛函理论
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基于代谢重编程探析肿瘤“体阴用阳”的病机实质
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作者 胡艳娥 文进渝 +4 位作者 何佳玮 蒋义芳 任益锋 由凤鸣 付西 《辽宁中医杂志》 北大核心 2026年第3期11-15,共5页
从“体阴用阳”出发,认为浊、痰、瘀、毒等多种病理产物凝滞胶结致有形实体为肿瘤体阴之象,癌毒挟火搏结妄动、流窜转移、噬精夺血则是肿瘤用阳的功能行为表征。代谢重编程重新定义了能量与物质在代谢网络中的流量与流向,其改变代谢模... 从“体阴用阳”出发,认为浊、痰、瘀、毒等多种病理产物凝滞胶结致有形实体为肿瘤体阴之象,癌毒挟火搏结妄动、流窜转移、噬精夺血则是肿瘤用阳的功能行为表征。代谢重编程重新定义了能量与物质在代谢网络中的流量与流向,其改变代谢模式倾向于生物合成以满足肿瘤物质需要是体阴的微观具象,加速攫取能量并重塑肿瘤微环境以实现快速增殖转移是用阳的直观体现。锚定肿瘤“体阴用阳”这对静与动的矛盾与代谢重编程所致物质、能量稳态失衡之间的契合性,提炼总结脾虚诱发浊邪凝滞、渐致“体阴”胶结,浊邪郁滞脾胃气机、引动“阴火”渐生,痰瘀挟火搏结走窜,终致“用阳”妄动为肿瘤递演的关键病机;进一步提出以扶正健脾化痰瘀祛“体阴”之形,补中升阳散阴火遏“用阳”之势,制方尚“和”复稳态平“阴阳”之偏为基本治则,尝试探讨调控代谢重编程阻延肿瘤进程的中医药理论模式,以期为肿瘤的中医药防治体系提供新见解。 展开更多
关键词 肿瘤 代谢重编程 体阴用阳 物质 能量
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车载香氛产品发展现状与创新方向
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作者 任红 屠国民 +5 位作者 姜宇翔 刘佳良 胡晓燕 王爽爽 徐智超 陈琼 《中国洗涤用品工业》 2026年第2期159-166,共8页
随着智能座舱与健康出行理念的普及,车载香氛将从附属品升级为重要车载配件,其发展现状与趋势值得深入研究。目前,市场正处于高速增长期,产品形态日趋智能化,现有产品形态多样,功能混乱,标准不一,本文从配方成分、工艺形态、功能宣称与... 随着智能座舱与健康出行理念的普及,车载香氛将从附属品升级为重要车载配件,其发展现状与趋势值得深入研究。目前,市场正处于高速增长期,产品形态日趋智能化,现有产品形态多样,功能混乱,标准不一,本文从配方成分、工艺形态、功能宣称与标准法规四个维度,综述了该行业现状。分析表明,天然安全、健康功能与智能可控释放技术是产品创新的核心驱动力;同时,功效宣称混乱与法规缺位是制约行业健康发展的主要瓶颈。车载香氛将深度融入智能座驾系统,并向更加注重健康防护。建立科学、统一的标准检测体系将成为产业发展的关键所在。 展开更多
关键词 车载香氛 配方成分 工艺形态 功能宣称 标准法规
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社区生态教育促进生态治理的逻辑关联、功能样态及保障机制
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作者 薛丁辉 《教育理论与实践》 北大核心 2026年第3期9-14,共6页
社区教育与社区治理存在天然联系。作为社区教育的重要内容,生态教育的目标设定、内容建构与活动实施均需以生态治理为导向,深度嵌入社区生态治理的全流程与各环节。社区生态教育促进生态治理的内在逻辑关联体现为内生动力的同源性、价... 社区教育与社区治理存在天然联系。作为社区教育的重要内容,生态教育的目标设定、内容建构与活动实施均需以生态治理为导向,深度嵌入社区生态治理的全流程与各环节。社区生态教育促进生态治理的内在逻辑关联体现为内生动力的同源性、价值向度的相通性、实践结构的一致性和效能演进的循环性。当前,社区生态教育促进生态治理的功能样态主要表现为,生态危机弥合功能、生态技能传递功能、生态行为唤醒功能和生态伦理培育功能。社区生态教育促进生态治理功能实现的保障机制包括决策导向、利益分配、监督评估和服务投入制度。社区生态教育多元功能的协同释放,能够推动社区生态治理向共治善治转型,持续提升基层治理体系与治理能力现代化水平。 展开更多
关键词 社区生态教育 生态治理 功能样态 保障机制
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太湖湖岸带木本、草本植物叶功能性状对淹水梯度的抵抗特征
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作者 蔡佳兵 张兴 +2 位作者 高飞 曲彦婷 张洪运 《东北农业大学学报》 北大核心 2026年第1期63-73,共11页
以太湖湖岸带3种淹水梯度下的适生物种为研究对象,通过测定其叶片形态结构特征(叶面积A_(L)、叶厚(T_(L))、叶干质量(W_(LD))、叶干物质质量分数(W_(L))、比叶面积(A_(SL)))、光合生理参数(叶绿素相对值(SPAD值)、净光合速率(P_(n))、... 以太湖湖岸带3种淹水梯度下的适生物种为研究对象,通过测定其叶片形态结构特征(叶面积A_(L)、叶厚(T_(L))、叶干质量(W_(LD))、叶干物质质量分数(W_(L))、比叶面积(A_(SL)))、光合生理参数(叶绿素相对值(SPAD值)、净光合速率(P_(n))、气孔导度(G_(s))、蒸腾速率(T_(r)))及化学计量特征(单位质量的叶碳质量分数(C_(mass))、叶氮质量分数(N_(mass))、叶磷质量分数(P_(mass)))等12个性状指标,应用方差、相关性及主成分分析方法,探讨不同淹水环境对木本与草本植物叶功能性状特征的影响,从生长型角度分析湖岸带植物类群对淹水梯度的适应策略。结果表明:(1)不同淹水梯度时,木本、草本植物的A_(L)、W_(LD)、W_(L)、A_(SL)、G_(s)、T_(r)、N_(mass)、P_(mass)均存在显著差异(P<0.05),且草本植物比木本植物在淹水梯度中的抗性更强;(2)太湖湖岸带木本植物叶片形成以G_(s)为核心的叶功能性状网络,而草本植物叶片形成以W_(LD)为核心的叶功能性状网络,适应湖岸带环境;(3)两类生长型植物在适应淹水梯度变化时,采取不同的权衡策略,木本植物在轻度淹水区(MFA)中形成以TL为核心的保守型资源利用策略,草本植物在非淹水区(NFA)中形成W_(L)、A_(SL)、N_(mass)、P_(mass)等多性状协同效应的快速资源利用策略。 展开更多
关键词 叶功能性状 淹水梯度 生长型 湖岸带植物 响应特征
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