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Anat Tsafrir Yagil Osem Hagai Shemesh Yohay Carmel Chanoch Soref Ofer Ovadia 《应用植被学》2019,22(1):115-126
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İrem Tüfekcioğlu;Çağatay Tavşanoğlu; 《Ecology and evolution》2024,14(3):e11145
Leaf traits are good indicators of ecosystem functioning and plant adaptations to environmental conditions. We examined whether leaf trait variability at species and community levels in Mediterranean woody vegetation is explained by growth form, regeneration mode, and vegetation type. We studied several plant communities across five vegetation types – semi-closed forest, open forest, closed shrubland, open shrubland, and scrubland – in southwestern Anatolia, Türkiye. Using linear mixed models, community-weighted trait means, and principal component analysis, we tested how much variability in three leaf traits (specific leaf area, leaf thickness, and leaf area) is accounted for species, growth form, regeneration mode, and vegetation type. Despite a large amount of leaf trait variability both within- and among-species existed, functional groups still accounted for a significant part of this variability. Resprouters had higher SLA and leaf area and lower leaf thickness than non-resprouters. However, further functional separation in regeneration mode, by considering the propagule-persistence trait and the seed bank locality, explained leaf trait variability better than only resprouting ability. Although no consistent pattern was observed in three leaf traits in the growth form, we found evidence for the difference in SLA and leaf thickness between shrubs and large shrubs, and subshrubs had smaller leaves than other growth forms. Vegetation type also accounted for a substantial amount of leaf trait variability. Specifically, plant communities in closed habitats had larger leaf area than open ones, and those in scrublands had higher SLA, lower leaf thickness, and lower leaf area than other vegetation types. Climate and phylogeny had limited contribution to the results obtained, with the exception of a significant phylogenetic effect in explaining the differences in SLA between resprouters and non-resprouters. Our results suggest that multiple drivers are responsible for shaping plant trait variability in Mediterranean plant communities, including growth form, regeneration mode, and vegetation type. 相似文献
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Mediterranean ecosystems comprise the second biodiversity hotspot area after tropical rain forests and will be most affected by global climate change. Therefore, it is important to understand community dynamics for effective conservation in this region. We investigated the relationships between soil moisture, nitrogen forms and community structuring in Quercus ilexL., Erica arborea L. and Sarcopoterium spinosum (L.) Spach communities, representing different successional stages, distributed as Mediterranean enclaves on the Sinop Peninsula (Turkey). The soil moisture, ammonium, nitrate and nitrite content were measured seasonally. Differences in these abiotic parameters within and between communities over seasons were tested. Previously collected biotic data were then used to analyze the relationship between soil parameters and community structure. Significant differences in soil parameters within and between seasons were found within and between communities. Our results show that there are different relationships between soil moisture, nitrogen forms and community structure in Mediterranean plant communities representing different successional stages. Differentiation in vegetation structure during succession cause changes especially in the water and nitrate content of the soil, and these changes in turn affect the continuity of community structure in Mediterranean plant communities. 相似文献
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M. Cristina Pedroso M. Salom Pais 《In vitro cellular & developmental biology. Plant》1995,31(1):31-35
Summary Two methods (I and II) for somatic embryo production from embryogenic suspension cultures ofCamellia japonica are presented. Method I, embryogenic suspension cultures, was established from suspension cultures initiated from leaf-derived
callus. These cultures were maintained by reducing agitation and increasing subculture interval. Induction of somatic embryogenesis
was achieved in MS28 medium, 6, 12, 24, and 36 mo. after culture establishment. Embryo production decreased after 1 yr of
culture. Method II, suspensions of single embryogenic cells and proembryos, was obtained from leaves cultured in liquid MS13
medium 6 wk after culture initiation. Embryo production was 23 embryos/ml. Germination of cell suspension-derived embryos
on MS56 medium was 16.7 % (±4.2%) for method I, and 35.4% (±5.1%) for method II. The embryos germinated into
plantlets with 0 to 7 axillary shoots. 相似文献
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BURAK K. PEKIN ROY S. WITTKUHN MATTHIAS M. BOER CRAIG MACFARLANE PAULINE F. GRIERSON 《Austral ecology》2012,37(3):330-338
Frequent fires reduce the abundance of woody plant species and favour herbaceous species. Plant species richness also tends to increase with decreasing vegetation biomass and cover due to reduced competition for light. We assessed the influence of variable fire histories and site biomass on the following diversity measures: woody and herbaceous species richness, overall species richness and evenness, and life form evenness (i.e. the relative abundance or dominance among six herbaceous and six woody plant life forms), across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands in south‐west Australia. Fire frequency was defined as the total number of fires over a 30‐year period. Overall species richness and species evenness did not vary with fire frequency or biomass. However, there were more herbaceous species (particularly rushes, geophytes and herbs) where there were fewer shrubs and low biomass, suggesting that more herbaceous species coexist where dominance by shrubs is low. Frequently burnt plots also had lower number and abundance of shrub species. Life form evenness was also higher at both high fire frequency and low biomass sites. These results suggest that the impact of fire frequency and biomass on vegetation composition is mediated by local interactions among different life forms rather than among individual species. Our results demonstrate that measuring the variation in the relative diversity of different woody and herbaceous life forms is crucial to understanding the compositional response of forests and other structurally complex vegetation communities to changes in disturbance regime such as increased fire frequency. 相似文献
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B. E. L. Cerabolini S. Pierce A. Verginella G. Brusa R. M. Ceriani S. Armiraglio 《Plant biosystems》2016,150(3):550-557
Species-rich meadow and pasture habitats are recognised by the European Union Habitats Directive as targets for biodiversity conservation. High species richness is hypothesised to be associated with diversity in plant functional traits and life-history strategies, which are potentially restricted in situations of extremely high and low biomass production. However, variability in functional traits has yet to be investigated across a broad biomass range in nature. We measured variability in a range of functional traits and Grime's competitor, stress-tolerator, ruderal (CSR) strategies for species comprising lowland meadows, subalpine pastures, abandoned grassland and field margins at sites in northern Italy, alongside peak above-ground biomass. The factor most highly and positively correlated with species richness was strategy richness (the number of CSR strategies; Pearson's r = 0.864, P < 0.0001, n = 39), followed by variance in traits involved in leaf resource economics and the timing of flowering. Species richness, trait variance and strategy richness were greatest at intermediate biomass. Thus whilst extremes of biomass production were associated with relatively few taxa exhibiting similar trait values and specialised strategies, greater species richness was apparent in meadows and pastures in which species exhibited divergence in resource economics trait values, reproductive timing and strategy richness. 相似文献
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植物功能性状是植物对生境长期适应所形成的可测量特征,受植物遗传特性和环境因子的共同影响。祁连山是我国干旱区的一条重要山脉,北坡海拔介于2000—5000 m,分布着青海云杉、祁连圆柏等10余种木本植物。深入了解祁连山区木本植物功能性状随海拔梯度分异特征对认识山地植物的适应性和植被垂直地带分布具有重要意义。选取祁连山北坡天然分布的11种木本植物,其中灌木9种,分别是金露梅(Potentilla fruticosa)、银露梅(Potentilla glabra)、水栒子(Cotoneaster multiflorus)、猫儿刺(Ilex pernyi)、吉拉柳(Salix gilashanica)、鬼箭锦鸡儿(Caragana jubata)、刚毛忍冬(Lonicera hispida)、高山绣线菊(Spiraea alpina)和鲜黄小檗(Berberis diaphana),乔木2种,分别是青海云杉(Picea crassifolia)和祁连圆柏(Juniperus przewalskii),调查了木质密度、胡伯尔值、叶面积、叶干物质含量、叶含水率和比叶面积6个枝、叶功能性状。结果表明... 相似文献
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Andrew G. Baker Claudia Catterall Kirsten Benkendorff Rod J. Fensham 《Austral ecology》2020,45(5):557-571
The expansion of rainforest pioneer trees into long‐unburnt open forests has become increasingly widespread across high rainfall regions of Australia. Increasing tree cover can limit resource availability for understorey plant communities and reduce understorey diversity. However, it remains unclear if sclerophyll and rainforest trees differ in their competitive exclusion of understory plant communities, which contain most of the floristic diversity of open forests. Here, we examine dry open forest across contrasting fire histories (burnt and unburnt) and levels of rainforest invasion (sclerophyll or rainforest midstorey) to hindcast changes in understorey plant density, richness and composition. The influence of these treatments and other site variables (midstorey structure, midstorey composition and soil parameters) on understorey plant communities were all examined. This study is the first to demonstrate significantly greater losses of understorey species richness, particularly of dry open‐forest specialists, under an invading rainforest midstorey compared to a typical sclerophyll midstorey. Rainforest pioneers displaced over half of the understorey plant species, and reduced ground cover and density of dry forest specialists by ~90%. Significant understorey declines also occurred with increased sclerophyll midstorey cover following fire exclusion, although losses were typically less than half that of rainforest‐invaded sites over the same period. Understorey declines were closely related to leaf area index and basal area of rainforest and wattle trees, suggesting competitive exclusion through shading and potentially belowground competition for water. Around 20% of displaced species lacked any capacity for population recovery, while transient seed banks or distance‐limited dispersal may hinder recovery for a further 68%. We conclude that rainforest invasion leads to significant declines in understorey plant diversity and cover in open forests. To avoid elimination of local native plant populations in open forests, fires should occur with sufficient frequency to prevent overstorey cover from reaching a level where shade‐intolerant species fail to thrive. 相似文献
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植物生长型和生活型是理解植物响应和适应环境变化的重要形态性状, 对研究植物与环境和生态系统功能的关系, 理解植物地理分布格局和生物多样性形成与维持机制具有重要意义。《中国植物志》和Flora of China中有关植物生长型和生活型的描述存在分类标准不统一, 部分信息缺失、错误或模糊不清等问题。本文基于全国和地方植物志书及野外调查的植物性状信息, 订正了中英文版维管植物的生长型和生活型性状, 建立了中国维管植物生长型和生活型数据集。该数据集包含35,329种维管植物, 内容包括植物名称、生长型和生活型性状及其数据来源, 其中植物名称包括来自《中国植物志》、Flora of China和来自《中国生物物种名录(2023版)》的两个分类系统版本, 以便读者相互对照不同分类系统的差异。依据茎木质化程度分为木本植物和草本植物两类, 木本植物有12,600种, 占35.7%; 草本植物为22,729种, 占64.3%。木本植物以中灌木生长型(2,917种, 占23.2%)和常绿生活型(7,107种, 占56.4%)为主, 草本植物以杂类草生长型(19,900种, 占87.6%)和多年生生活型(19,554种, 占86.0%)为主。木本生长型中乔木物种以樟科和壳斗科占比较大, 灌木物种以杜鹃花科、蔷薇科和豆科占比较大; 常绿生活型以杜鹃花科占比较大, 落叶生活型以蔷薇科占比较大。草本生长型中杂类草以菊科占比较大, 禾草以禾本科占比较大; 生活型中一年生、二年生和多年生分别以禾本科、紫草科和菊科占优势。本数据集涵盖了目前中国所有维管植物物种的生长型和生活型信息, 可为植物性状研究提供数据基础。 相似文献
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Irena Šímová Jens‐Christian Svenning Jens Kattge Kristine Engemann Brody Sandel Robert K. Peet Susan K. Wiser Benjamin Blonder Brian J. McGill Brad Boyle Naia Morueta‐Holme Nathan J. B. Kraft Peter M. van Bodegom Alvaro G. Gutiérrez Michael Bahn Wim A. Ozinga Anna Tószögyová Brian J. Enquist 《Journal of Biogeography》2018,45(4):895-916
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Woody tree species in seasonally dry tropical forests are known to have traits that help them to recover from recurring disturbances such as fire. Two such traits are resprouting and rapid post‐fire growth. We compared survival and growth rates of regenerating small‐sized individuals (juveniles) of woody tree species after dry season fire (February–March) at eight adjacent pairs of burnt and unburnt transects in a seasonally dry tropical forest in southern India. Juveniles were monitored at 3‐mo intervals between August 2009 and August 2010. High juvenile survivorship (>95%) was observed in both burnt and unburnt areas. Growth rates of juveniles, analyzed at the community level as well as for a few species individually (especially fast‐growing ones), were distinctly higher in burnt areas compared to unburnt areas after a fire event, particularly during the pre‐monsoon season immediately after a fire. Rapid growth by juveniles soon after a fire may be due to lowered competition from other vegetative forms such as grasses, possibly aided by the availability of resources stored belowground. Such an adaptation would allow a juvenile bank to be retained in the understory of a dry forest, from where individuals can grow to a possible fire‐tolerant size during favorable conditions. 相似文献
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Combined use of leaf size and economics traits allows direct comparison of hydrophyte and terrestrial herbaceous adaptive strategies 总被引：1，自引：0，他引：1
Background and Aims
Hydrophytes generally exhibit highly acquisitive leaf economics. However, a range of growth forms is evident, from small, free-floating and rapidly growing Lemniden to large, broad-leaved Nymphaeiden, denoting variability in adaptive strategies. Traits used to classify adaptive strategies in terrestrial species, such as canopy height, are not applicable to hydrophytes. We hypothesize that hydrophyte leaf size traits and economics exhibit sufficient overlap with terrestrial species to allow a common classification of plant functional types, sensu Grime''s CSR theory.Methods
Leaf morpho-functional traits were measured for 61 species from 47 water bodies in lowland continental, sub-alpine and alpine bioclimatic zones in southern Europe and compared against the full leaf economics spectrum and leaf size range of terrestrial herbs, and between hydrophyte growth forms.Key Results
Hydrophytes differed in the ranges and mean values of traits compared with herbs, but principal components analysis (PCA) demonstrated that both groups shared axes of trait variability: PCA1 encompassed size variation (area and mass), and PCA2 ranged from relatively dense, carbon-rich leaves to nitrogen-rich leaves of high specific leaf area (SLA). Most growth forms exhibited trait syndromes directly equivalent to herbs classified as R adapted, although Nymphaeiden ranged between C and SR adaptation.Conclusions
Our findings support the hypothesis that hydrophyte adaptive strategy variation reflects fundamental trade-offs in economics and size that govern all plants, and that hydrophyte adaptive strategies can be directly compared with terrestrial species by combining leaf economics and size traits. 相似文献16.
Fire ecology has been hindered by the lack of comparable, affordable protocols to quantify the flammability of whole plants over large numbers of species. We describe a low‐tech device that can be carried to the field and that allows highly standardized measurement of the flammability of whole individuals or portions up to 70 cm long. We illustrate its potential with results for 34 species belonging to different growth forms from central Argentina. The device consists of an 85 × 60 cm half‐cut metallic barrel placed horizontally and mounted on a removable metallic structure. It contains three parallel burners, a grill with an attached gauging thermometer and a blowtorch. Burners and blowtorch are connected to a propane–butane gas cylinder. Plant samples are placed on the grill and preheated with the burners for 2 min at 150°C. They are then ignited for 10 s with the blowtorch while the burners are kept on. Four parameters are measured for each sample: maximum temperature reached, burning time, burnt length and burnt biomass percentage. These parameters are used to construct a compound index of flammability for each sample that ranges between 0 (no flammability) and around 3 (maximum flammability). We obtained a wide range of values for flammability and all its components. Most of this variability was accounted for by differences between growth forms and species, rather than by differences at the level of replicates. This suggests that the device and protocol are sensitive enough to detect flammability differences among plants with different functional traits, and at the same time robust enough to produce consistent results among samples with similar traits. A major advantage is that plant architecture is kept almost intact, providing a flammability measure much closer to that of whole individuals in the field than those obtained by other standard protocols in use. The device and protocol presented here should facilitate the acquisition of comparable flammability data over large numbers of species from different floras and ecosystems, potentially contributing to several fields of research, such as functional ecology, evolutionary ecology and vegetation‐atmosphere modelling. 相似文献
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Yu Fukasawa;Hiroyuki Kitabatake; 《Ecology and evolution》2024,14(6):e11508
Wood decay fungi alter the abiotic and biotic properties of deadwood, which are important as nurse logs for seedling regeneration. However, the relationship between fungal decay type and seedling performance has not been evaluated experimentally. In this study, we examined the germination, growth, and survival of six arbuscular mycorrhizal (AM) and six ectomycorrhizal (ECM) tree species on three substrates (pine logs with brown and white rot and soil) by conducting seed-sowing experiments in a mixed forest dominated by Pinus densiflora and Quercus serrata. Analysis using ribosomal DNA internal transcribed spacer 1 (rDNA ITS1) sequencing revealed that the fungal community was significantly different across three substrates. The richness of operational taxonomic units (OTUs) of AM and ECM fungi was the largest on brown rot logs and soil, respectively. The substrate significantly affected the seedling performance when comparing wood decay types, but these were not consistent across the mycorrhizal status of the seedlings. Nevertheless, seedlings of some AM trees showed better growth and enhanced mycorrhizal colonization on brown rot logs than on white rot logs. The wood decay type influenced fungal communities in the logs and the performance of some seedling species partly by different mycorrhizal colonization rates. However, the effect was seedling species dependent and showed no apparent difference between AM and ECM trees. 相似文献
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Woody encroachment into grasslands is occurring across the world and is of concern to land managers. Studies of forest–grassland boundaries have informed models describing factors that govern tree establishment and the maintenance and origin of grassland ecosystems. Central to these models is the role of fire relative to ‘bottom up’ resources such as soil and the geological substrate in determining the extent of grassland and forest in the landscape. The view that human lit fires have shaped vegetation across the Australian continent has been bolstered by early 19th century observations of Aboriginal‐set fires in Tasmanian montane grasslands and the documented encroachment of trees into these grasslands in the 20th century. We examined the pattern of lateral encroachment of woolly tea‐tree (Leptospermum lanigerum (Sol. ex Aiton) Sm.) into these grasslands and used tree ring chronologies to investigate (i) past fire activity and (ii) how the geological substrate mediates growth rates of L. lanigerum. Changes in fire regimes inferred from L. lanigerum recruitment were corroborated by historical records. Encroachment (and increases in woody cover) of trees into grasslands was highest on granitic substances, although L. lanigerum growth rates were highest on basalt substrates, followed by conglomerate, granite and Mathinna sediments. Frequent burning up to the 1980s may have stymied the encroachment of trees in grasslands underlain by basalt. Growth rates decreased with increasing distance from the forest edge. This may be due to incremental changes in soil resources, grass competition and/or microclimate. The dynamics between grasslands and forests in montane Tasmania are consistent with tree growth–fire interaction models that highlight the interplay of edaphic factors, growth rates and fire history. Such complexity cautions against generalizations concerning the direct effects of landscape fire in shaping vegetation distribution across Australia. 相似文献
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Josep Padullés Cubino; 《Oikos》2023,2023(2):e09579
Understanding how species turnover responds to environmental change may provide insights into the ecological factors influencing biogeographical patterns. Here, I examined geographic patterns in taxonomic and functional turnover of tree assemblages in Europe and compared the influence of environmental factors on turnover. I conducted a principal component analysis with nine above- and below-ground plant traits for 210 tree species. I used the resulting four principal components (82% of the variance) to create five functional dendrograms considering all trait dimensions together and individually. Further, I used species composition and the functional dendrograms to calculate pairwise taxonomic and functional turnover between tree assemblages in 100 × 100 km grid cells across Europe. To assess the influence of temperature, precipitation, precipitation seasonality, soil pH and geographic distance on taxonomic and functional turnover, I conducted multiple regression on distance matrices (MRM). I also compared the slope of the relationship between functional turnover and environmental distance among trait dimensions to detect what ecological strategies may be more sensitive to environmental changes. I found that mean taxonomic and functional turnover was particularly high in lowland areas of the Mediterranean Basin. Geographic patterns of individual trait dimensions largely reproduced those considering all trait dimensions together, additionally revealing some regional differences. MRM explained a similar fraction of the variation in taxonomic and functional turnover. The influence of environmental distance was stronger for trait dimensions related to tree size and woodiness than for trait dimensions related to the leaf and root economics. I conclude that geographic patterns in the turnover of tree assemblages in Europe coincide with major biome transitions. Deterministic assembly processes act differently on key ecological strategies of tree assemblages at the continental scale. 相似文献