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We investigated the connection between plant species diversity and climate by using a process‐based, generic plant model. Different ‘species' were simulated by different values for certain growth‐related model parameters. Subsequently, a wide range of values were tested in the framework of a ‘Monte Carlo' simulation for success; that is, the capability of each plant with these parameter combinations to reproduce itself during its lifetime. The range of successful parameter combinations approximated species diversity. This method was applied to a global grid, using daily atmospheric forcing from a climate model simulation. The computed distribution of plant ‘species' diversity compares very well with the observed, global‐scale distribution of species diversity, reproducing the majority of ‘hot spot' areas of biodiversity. A sensitivity analysis revealed that the predicted pattern is very robust against changes of fixed model parameters. Analysis of the climatic forcing and of two additional sensitivity simulations demonstrated that the crucial factor leading to this distribution of diversity is the early stage of a plant's life when water availability is highly coupled to the variability in precipitation because in this stage root‐zone storage of water is small. We used cluster analysis in order to extract common sets of species parameters, mean plant properties and biogeographic regions (biomes) from the model output. The successful ‘species' cannot be grouped into typical parameter combinations, which define the plant's functioning. However, the mean simulated plant properties, such as lifetime and growth, can be grouped into a few characteristic plant ‘prototypes', ranging from short‐lived, fast growing plants, similar to grasses, to long‐lived, slow growing plants, similar to trees. The classification of regions with respect to similar combinations of successful ‘species' yields a distribution of biomes similar to the observed distribution. Each biome has typical levels of climatic constraints, expressed for instance by the number of ‘rainy days' and ‘warm days'. The less the number of days favourable for growth, the greater the level of constraints and the less the ‘species' diversity. These results suggest that climate as a fundamental constraint can explain much of the global scale, observed distribution of plant species diversity. 相似文献
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Chiara Molinari Veiko Lehsten Olivier Blarquez Christopher Carcaillet Basil A. S. Davis Jed O. Kaplan Jennifer Clear Richard H. W. Bradshaw 《Global Change Biology》2018,24(10):4929-4945
The influence of different drivers on changes in North American and European boreal forests biomass burning (BB) during the Holocene was investigated based on the following hypotheses: land use was important only in the southernmost regions, while elsewhere climate was the main driver modulated by changes in fuel type. BB was reconstructed by means of 88 sedimentary charcoal records divided into six different site clusters. A statistical approach was used to explore the relative contribution of (a) pollen‐based mean July/summer temperature and mean annual precipitation reconstructions, (b) an independent model‐based scenario of past land use (LU), and (c) pollen‐based reconstructions of plant functional types (PFTs) on BB. Our hypotheses were tested with: (a) a west‐east northern boreal sector with changing climatic conditions and a homogeneous vegetation, and (b) a north‐south European boreal sector characterized by gradual variation in both climate and vegetation composition. The processes driving BB in boreal forests varied from one region to another during the Holocene. However, general trends in boreal biomass burning were primarily controlled by changes in climate (mean annual precipitation in Alaska, northern Quebec, and northern Fennoscandia, and mean July/summer temperature in central Canada and central Fennoscandia) and, secondarily, by fuel composition (BB positively correlated with the presence of boreal needleleaf evergreen trees in Alaska and in central and southern Fennoscandia). Land use played only a marginal role. A modification towards less flammable tree species (by promoting deciduous stands over fire‐prone conifers) could contribute to reduce circumboreal wildfire risk in future warmer periods. 相似文献
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Hannah J. White W. Ian Montgomery Lenka Storchová David Hořák Jack J. Lennon 《Ecology and evolution》2018,8(15):7365-7377
Environmental change has reshuffled communities often causing taxonomic homogenization rather than differentiation. Some studies suggest that this increasing similarity of species composition between communities is accompanied by an increase in similarity of trait composition—functional homogenization—although different methodologies have failed to come to any consistent conclusions. Functional homogenization could have a large effect on ecosystem functioning and stability. Here, we use the general definition of homogenization as “reduced spatial turnover over time” to compare changes in Simpson's beta diversity (taxonomic turnover) with changes in Rao's quadratic entropy beta diversity (functional turnover) in British breeding birds at three spatial scales. Using biotic and climatic variables, we identify which factors may predispose a site to homogenization. The change in turnover measures between two time periods, 20 years apart, was calculated. A null model approach was taken to identify occurrences of functional homogenization and differentiation independent of changes in taxonomic turnover. We used conditional autoregressive models fitted using integrated nested Laplace approximations to determine how environmental drivers and factors relating to species distributions affect changes in spatial turnover of species and functional diversity. The measurement of functional homogenization affects the chance of rejection of the null models, with many sites showing taxonomic homogenization unaccompanied by functional homogenization, although occurrence varies with spatial scale. At the smallest scale, while temperature‐related variables drive changes in taxonomic turnover, changes in functional turnover are associated with variation in growing degree days; however, changes in functional turnover become more difficult to predict at larger spatial scales. Our results highlight the multifactorial processes underlying taxonomic and functional homogenization and that redundancy in species traits may allow ecosystem functioning to be maintained in some areas despite changes in species composition. 相似文献
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从物种多样性和功能多样性探讨沉水植物群落对水深的响应可深刻揭示水深对群落构建的影响机制。以南四湖不同水深沉水植物群落为研究对象,对比分析了群落的9个加权功能性状(株高、茎分支数、茎节数、茎直径、根长、根围直径、生物量分配比、比叶面积、植物体磷含量)、5个物种多样性指数(Berger-Parker生态优势度指数、Margalef丰富度指数、Simpson多样性指数、Shannon-Wiener多样性指数和Pielou均匀度指数)和5个功能多样性指数(功能丰富度FRic指数、功能均匀度FEve指数、功能离散度FDiv指数、功能分散度FDis指数和二次熵Rao指数)以及物种多样性和功能多样性关系对水深的响应规律。研究结果表明:(1)水深可显著改变群落株高、根长、根围直径、比叶面积、生物量分配比和植物体磷含量6个加权功能性状;群落茎分支数、茎节数和茎直径3个加权功能性状对水深变化无显著响应;(2)水深可显著影响群落物种多样性和功能多样性,中等水深处沉水植物群落具有较高的Margalef丰富度指数、Shannon-Wiener多样性指数、Berger-Parker生态优势度指数、Pielou均匀度指数以及功能丰富度FRic指数、功能均匀度FEve指数、功能离散度FDis指数、二次熵Rao指数;(3)水深可改变5个物种多样性指数与功能丰富度FRic指数、功能均匀度FEve指数、功能离散度FDiv指数3个功能多样性指数间的相关关系,但对5个物种多样性指数与功能离散度FDis指数、二次熵Rao指数2个功能多样性指数间的相关关系无显著影响。研究结论为:群落不同测度的物种多样性和功能多样性指数及其相关关系对水深变化的响应迥异,在探讨水深对沉水植物群落构建的影响机制时应从多个方面综合考量。 相似文献
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表土孢粉模拟的中国生物群区 总被引:11,自引:0,他引:11
根据中国第四纪孢粉数据库提供的 6 41个表土孢粉资料 ,利用孢粉生物群区化方法 ,建立了具有 6 86个孢粉类群、31类植物功能型和 14种生物群区的孢粉生物群区化模型。经过检验 ,该模型在模拟中国生物群区、生物群区垂直分异和水平梯度分析方面均取得理想结果。模型已实现了计算机程序化 ,为重建过去地质历史时期的古生物群区和古气候分析 ,提供客观、准确的模型工具。 相似文献
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The uncertainty in simulations by a Global Biome Model (BIOME3) to alternative parameter values 总被引:3,自引:0,他引:3
The sensitivity of a global biome model (BIOME3) to uncertainty in parameter values was investigated by testing the model's sensitivity to minimum and maximum parameter values obtained from an extensive literature search. Simulations were conducted replacing the default parameter value by each of the maximum and minimum values determined from the literature. In doing so, the aim was to identify those parameters where the use of an alternate (observed) value leads to a significant change in the simulation of plant functional types at a global scale, in order to identify those which are functionally important to the model. BIOME3 was found to be insensitive to changes in the majority of its parameters, providing a generally sound foundation for confidence in model simulations. However, there was considerable sensitivity shown to over a quarter of the parameters. Three main types of parameters led to a change in plant functional types distribution relative to the control simulation: (i) parameters affecting the photosynthesis parameterization; (ii) parameters affecting the evapotranspiration parameterization; and (iii) root distribution which affected both parts of the model. The main causes of sensitivity were changes in the photosynthesis parameters leading to differential changes in plant functional type's net primary productivity. This caused a shift in the competitive balance between specific plant functional types or between C3 and C4 plant types, and a consequent change in their global distribution. Changes to the evapotranspiration parameters and root distribution similarly affected net primary productivity and soil moisture, and often led to shifts in the competitive balance between grass and trees. Changes in the value for several poorly known parameters produced substantial changes in the distribution of plant functional types, and reduced the κ‐statistic to a large degree, indicating areas of potential uncertainty in the model. This suggests that great care must be taken in prescribing values to these parameters and provides guidance on which parameters need further attention in observational work. 相似文献
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稀有种是海洋生态系统中物种共存与多样性维持的重要类群,但其对鱼类群落物种多样性、功能多样性的调控机制不明。以三门湾鱼类群落为研究对象,基于地理范围、栖息地特异性和种群规模大小识别群落稀有种,利用自抽样技术模拟稀有种在自然条件下的随机丧失,探讨稀有种丧失对物种多样性、功能多样性的影响。结果表明,稀有种的丧失造成物种丰富度与功能丰富度呈显著下降趋势;物种均匀度在夏季稳定性较低,在其余季节稳定性较高,功能均匀度在冬季稳定性较高,在其余季节稳定性较低,这与稀有种地理分布范围及其功能性状所占据的空间特殊位置有关;Simpson指数与Shannon-Wiener指数呈现下降趋势,但前者数值变化区间小于后者,这与群落丰富度、均匀度密切相关;功能离散度在夏季呈下降趋势,而在其他季节保持相对稳定,主要受位于性状空间边缘物种数量的影响。总体上,稀有种的丧失对物种多样性、功能多样性的稳定性产生影响,且物种多样性与功能多样性的相关性较强。 相似文献
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Bianca O. Andrade Camila L. Bonilha Gerhard E. Overbeck Eduardo Vlez‐Martin Rosngela G. Rolim Srgio Augusto L. Bordignon Angelo A. Schneider Cleusa Vogel Ely Diber B. Lucas len N. Garcia Emily D. dos Santos Fbio P. Torchelsen Mariana S. Vieira Pedro J. S. Silva Filho Pedro M. A. Ferreira Rafael Trevisan Raquel Hollas Srgio Campestrini Valrio D. Pillar Ilsi I. Boldrini 《应用植被学》2019,22(1):168-184
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Chen Xu-Dong 《植物学报(英文版)》2001,43(2):201-209
A model for China biome reconstruction was deduced from 641 original pollen data of surface samples by biomazition procedure developed by Prentice et al . Fourteen biome types of China were recognised based on 31 plant fuctinooal types from 686 pollen types. The procedure successfully delineated the major vegetation types in China and, therefore, can provide an objective methord for China biome reconstruction of geological time, e.g. for 6 ka BP and 18 ka BP. 相似文献
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区域尺度的中国植物功能型与生物群区 总被引:13,自引:0,他引:13
倪健 《Acta Botanica Sinica》2001,43(4):419-425
利用“生态-外貌”原则,中国的现状植被类型及其分布,确定中国的39种优势植物功能型:高山常绿针叶、北方常绿针叶、北方夏绿针叶、冷温带常绿针叶、温带常绿针叶、暖温带常绿阔叶、暖温带硬叶阔叶、暖温带夏绿阔叶、热带常绿阔叶、热带 雨绿阔叶、热带落叶阔叶、暖温带竹、高山/亚高山灌木、温带草原灌木、温带荒漠灌木、冷温带灌木、温带灌木、暖温带灌木、热带灌木、干旱灌木、高山草、荒漠草、温带草原草、温带草、沼泽草、红树、北方农作物、冷温带农作物、温带农作物、暖温带农作物、热带农作物和裸地。再依据优势植物功能型归并中国的21类潜在生物群区:北方(寒温带)落叶林、北方(寒温带)常绿林、冷温带针阔叶混交林、温带落叶阔叶林、暖温带(亚热带)落叶常绿阔叶混交林、暖温带(亚热带)常绿阔叶林、暖温带(亚)常绿阔叶季风林、热带雨林、热带季雨林、热带落叶林、红树林、干旱疏林/稀树草原、;温带草甸/稀树草原、温带草原、温带半草原、温带荒漠、温带半荒漠、高山/高山针叶林、高山/亚高山灌丛/草甸、高山/亚高山草原和高山/亚高山荒漠。如果考虑现状农业植被类型:一年一熟农作物、二年三熟农作物、一年二熟农作物和一年三熟农作物,可归并为25类现状生物群区。这是全球生态学和古生态学研究中区域尺度旧我国植物功能型和生物群区分类的一次尝试。 相似文献
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黄海山东海域春、秋季鱼类群落多样性 总被引:4,自引:0,他引:4
根据2006年春季(5月)和秋季(10月)黄海山东海域疏目变水层双拖网调查数据,作者对该海域鱼类群落多样性、空间分布及长度谱特征进行了研究。调查共捕获鱼类61种,其中鲈形目种类最多(27种),其次为鲱形目(8种)和鲉形目(7种);按摄食类型可分为浮游动物食性、浮游动物/底栖动物食性、底栖动物食性、底栖动物/游泳动物食性、游泳动物食性、杂食性、碎屑食性7个类群,其中浮游动物食性占渔获物重量组成的82.5%。春、秋季鱼类群落均主要由小型种类占优势,春季优势种有3种,为玉筋鱼(Ammodytes personatus)、鳀(Engraulis japonicus)和方氏锦鳚(Pholis fangi),秋季优势种有5种,分别是鳀、青鳞小沙丁鱼(Sardinella zunasi)、玉筋鱼、小黄鱼(Larimichthys polyactis)和赤鼻棱鳀(Thryssa kammalensis)。丰富度指数(D)、Shannon-Wiener多样性指数(H’)、均匀度指数(J’)的空间异质性明显,表现出近岸海域(尤其是青岛-乳山南部近岸海域)较高,深水区较低的态势,但多样性指数的季节间差异不显著。资源量与Shannon-Wiener多样性指数(H’)、均匀度指数(J’)、功能团多样性指数(FD)均呈负相关关系,与种类丰富度指数(D)则无相关关系。春、秋季鱼类群落长度谱曲线斜率均小于-0.2,而截距均大于10,与该海域1985年及2000年的研究结果相比,长度谱斜率显著降低、截距显著增加,这与小型个体种类占优势密切相关。与历史资料相比,黄海山东海域鱼类群落多样性下降,小型个体比例上升,资源呈衰退趋势。 相似文献
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Rebecca L. Selden Ryan D. Batt Vincent S. Saba Malin L. Pinsky 《Global Change Biology》2018,24(1):117-131
Asymmetries in responses to climate change have the potential to alter important predator–prey interactions, in part by altering the location and size of spatial refugia for prey. We evaluated the effect of ocean warming on interactions between four important piscivores and four of their prey in the U.S. Northeast Shelf by examining species overlap under historical conditions (1968–2014) and with a doubling in CO2. Because both predator and prey shift their distributions in response to changing ocean conditions, the net impact of warming or cooling on predator–prey interactions was not determined a priori from the range extent of either predator or prey alone. For Atlantic cod, an historically dominant piscivore in the region, we found that both historical and future warming led to a decline in the proportion of prey species’ range it occupied and caused a potential reduction in its ability to exert top‐down control on these prey. In contrast, the potential for overlap of spiny dogfish with prey species was enhanced by warming, expanding their importance as predators in this system. In sum, the decline in the ecological role for cod that began with overfishing in this ecosystem will likely be exacerbated by warming, but this loss may be counteracted by the rise in dominance of other piscivores with contrasting thermal preferences. Functional diversity in thermal affinity within the piscivore guild may therefore buffer against the impact of warming on marine ecosystems, suggesting a novel mechanism by which diversity confers resilience. 相似文献
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城市自生草本植物的物种多样性和功能多样性直接影响城市生态系统的功能和稳定性,但目前相关研究依然很缺乏。以深圳市为例,基于建成区600个1hm2样地的现场调查数据,分析自生草本植物的群落结构、物种多样性、群落功能特征及功能多样性。结果显示:(1)调查共记录自生草本植物61科178属273种,其中多年生草本占54.6%,乡土植物占65.6%。(2)占明显优势的功能特征有中小型叶(91.85%)、草质叶(42.59%)、纸质叶(32.96%)、叶片无毛或近无毛(56.67%)、中等密度绒毛(40.37%)、叶面较粗糙(52.59%)、花期4—6个月(50.78%)、果期4—6个月(49.22%)、干果(86.03%)。(3)群落类型间功能丰富度FDp、功能离散度Rao二次熵差异极显著(P<0.01)、功能均匀度FEve差异显著(P<0.05)。(4)公园绿地的物种多样性指数明显高于其他三类绿地;不同绿地类型间的功能丰富度和功能离散度在滞尘、降噪、降温增湿及生物多样性保护方面都有极显著差异(P<0.01),功能均匀度只在滞尘及生物多样性保护方面差异极显著(P<0.01)。(5)各功能多样性指数均与Margalef指数、Simpson指数及Shannon-Wiener指数呈极显著正相关关系(P<0.01)。研究结论和方法为维护城市生态系统稳定性、建设生态宜居城市、促进城市可持续发展提供理论依据。 相似文献
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以中国西南地区(云南、贵州、四川和重庆)为研究区,基于中国植被图划分植物功能型,筛选影响各植物功能型分布的主导环境因子,进而通过最大熵模型结合未来气候情景(2050年)预测西南地区植物功能型地理分布。结果表明:(1)根据植物冠层特征(针叶/阔叶、常绿/落叶)及对水分和温度的需求,结合研究区实际植被数据,筛选得到15类植物功能型,包含6类乔木、6类灌木和3类草本功能型;(2)影响西南地区热带乔木分布的主导因子为最冷月最低温度和年降水量(贡献率达90.3%),亚热带植物功能型分布主要受到温度变化影响(贡献率达41.7%),温带植物功能型则受降水因子的影响最大(贡献率约40.1%),高寒草甸草和高寒常绿阔叶灌木主要受温度和海拔因子影响,高寒落叶阔叶灌木受降水因子影响大;(3)随CO2排放量增加,未来西南各植物功能型分布呈现不同变化,其中,热带常绿阔叶乔木适宜区逐渐扩大;亚热带落叶木本类植物功能型的高适宜区面积2050年(RCP8.5)增至10.3%,呈东移趋势;亚热带常绿木本和草本类植物功能型适宜区广(占研究区总面积86.5%),未来气候下分布呈不规则波动;温带植物功能... 相似文献
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Summary A systematic sample of 416 stands of vegetation was subjected to Indicator Species Analysis which classified the stands into sixteen Groups. For practical reasons these were amalgamated into ten Interpreted Groups which are described in terms of species representation and cover. The distribution of stands in the various Groups is described and is related where possible to environmental factors. 相似文献