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1.
Kerstin Pierick;Roman M. Link;Christoph Leuschner;Jürgen Homeier; 《Oikos》2023,2023(1):e08975
With increasing elevation, trees in tropical montane forests have to invest larger fractions of their resources into their fine roots in order to compensate for increasingly unfavorable soil conditions. It is unclear how elevation and related edaphic changes influence the variability in tree fine root traits and belowground functional diversity. We measured six fine root traits related to resource acquisition on absorptive fine roots of 288 trees from 145 species along an elevational gradient from 1000 m to 3000 m a.s.l. in tropical montane forests of the Ecuadorian Andes. We analyzed trait relationships with elevation and soil nutrient availability, and tested whether root functional diversity varied along these gradients. Fine roots at higher elevations and at more nutrient-poor sites were thicker, had higher tissue densities, and lower specific root length and nutrient concentrations than at lower elevations. These trends were diluted by the coexistence of tree species with a broad range of different root traits within communities particularly towards lower elevations, where root functional diversity was significantly higher. We conclude that nutrient limitation and potentially further adverse conditions at higher elevations are strong environmental filters that lead to trait convergence towards a conservative resource use strategy, whereas different trait syndromes are equally successful at lower elevations. 相似文献
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We studied selected leaf traits [leaf area (LA), leaf water content (LWC), leaf fresh weight (LFW), leaf dry weight (LDW), specific leaf area (SLA) and chlorophyll content] of eight woody species (Shorea robusta, Buchanania lanzan, Diospyros melanoxylon, Lagerstroemia parviflora, Lannea coromandelica, Terminalia tomentosa, Holarrhena antidysenterica and Lantana camara) dominant at four sites in a dry tropical deciduous forest over complete two annual cycles (2008–2010). Our results showed that leaf traits varied across species (1.7–11.5 fold), months (1.2–1.5 fold) and sites (1.1–1.3 fold). However, leaf traits showed smaller variation between sites than between species. Leaf lifespan varied from 7 months (L. coromandelica) to 12 months (S. robusta). On the same sites, species differed in the length of deciduous period. The maximum LA, LDW, LFW and LWC were recorded for the semi-evergreen species, SLA for long-deciduous species and chlorophyll content for short-deciduous species, respectively. The coefficient of variation was maximum for LDW and minimum for chlorophyll content. Among the eight woody species, T. tomentosa exhibited the greatest LA, LDW, LFW and LWC. LA, LWC, LFW, LDW, SLA, LD, SD, MD & SE confirm. 相似文献
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Elise Sivault Pita K. Amick Kyle N. Armstrong Vojtech Novotny Katerina Sam 《Biotropica》2023,55(1):81-94
Over the past decades, elevational gradients have become a powerful tool with which to understand the underlying cause(s) of biodiversity. The Mt. Wilhelm elevational transect is one such example, having been used to study the birds, insects, and plants of Papua New Guinea (PNG). However, a survey of mammals from this forest elevational transect was lacking. We thus aimed to investigate patterns in the community structure and species richness of bats (Chiroptera) along the transect, link the species to available regional data, and explain the observed patterns by including environmental characteristics. Bat assemblages were surveyed between 200 m and a timberline at 3700 m a.s.l. at eight study sites separated by 500 m in elevation. We conducted mist-netting and acoustic surveys to detect and identify species at each site. Regional data were compiled to compare local with regional diversity. Finally, biotic (i.e., food availability, habitat features) and abiotic (i.e., mean daily temperature) factors were included in our analyses to disentangle the ecological drivers underlying bat diversity. Results revealed that species richness decreases with ascending elevation and was best explained by a corresponding decrease in temperature. We observed both turnover and nestedness of the species composition at regional scale whereas turnover was dominant at local scale. Extensions and shifts of bat elevational ranges were also found in Mt. Wilhelm. Consequently, despite that the study was restricted to one mountain in PNG, it demonstrates how basic inventory surveys can be used to address ecological questions in other similar and undisturbed tropical mountains. 相似文献
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Sarah C. Maunsell Chris J. Burwell Rebecca J. Morris William J. F. McDonald Edward D. Edwards Rolf G. Oberprieler Roger L. Kitching 《Austral ecology》2016,41(3):238-247
Leaf miners are specialist herbivorous insects that are potentially vulnerable to environmental change because of their dependency on particular host plants. Little, however, is known about how climate affects the distribution of leaf miner communities and their interactions with host plants. Elevational gradients are useful tools for understanding how ecological communities respond to local clines in climate. Given that plant communities are known to undergo elevational turnover in response to changes in climatic conditions, we expect that leaf miner species will also change with elevation. We repeatedly hand collected leaf miners along three elevational gradients in subtropical rainforest in eastern Australia. Individual leaf miners were counted and identified to species, and their host plants were recorded. We tested if leaf miner species richness and the number of unique interactions among leaf miner and host plant species were affected by elevation. We also tested if the composition of leaf miner species and the composition of interactions between leaf miners and host plants showed a relationship with elevation. The rarefied number of unique leaf miner–host plant interactions significantly decreased with elevation, with a slight peak at approx. 700 m a.s.l., while neither rarefied or observed species richness (species density) of leaf miners nor observed numbers of unique interactions (interaction density) were significantly affected by elevation. The composition of leaf miner species and the composition of leaf miner–host plant interactions (occurrence of pairwise interactions) were significantly related to elevation. Elevational turnover in leaf miner species composition indicated that different species varied in their response to changes in biotic and/or abiotic conditions imposed by increasing elevation. Through our analyses, we identified four leaf miner species that may be locally vulnerable to climate change, as a result of their restricted elevational distribution and level of host specificity. 相似文献
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植物如何改变功能性状来适应环境一直是生态学的研究征点。为探究茂兰喀斯特森林不同演替阶段植物叶片的适应策略,该文以茂兰自然保护区5个不同演替阶段(草本、灌木、灌乔、乔木和顶极群落阶段)优势种为研究对象,测定不同演替阶段的优势植物叶片功能性状与土壤理化性质。结果表明：(1)随着植被正向演替的进行,土壤全氮(STN)含量、土壤有机质(SOM)含量、土壤含水量(SWC)逐渐增加,土壤全磷(STP)含量和土壤全钾(STK)含量先增加后减少,土壤pH值整体呈减小的趋势。(2)随着植被演替的进行,叶面积(LA)、叶干物质含量(LDMC)、叶厚度(LT)和叶片碳含量(LCC)逐渐上升,比叶面积(SLA)与叶片钾含量(LKC)则与之相反,叶片氮含量(LNC)呈先升后降的趋势,叶片磷含量(LPC)呈先降后升的趋势。(3)冗余分析表明,演替初期植物主要分布在土壤pH值高而STK、STP、SWC、SOM、STN相对低的环境中,群落内植物叶片采取高SLA、LNC、LPC,低LA、LDMC、LT、LWC的性状组合,演替晚期植物主要分布在土壤水分和养分含量较高的环境,LDMC、LT、LA、LWC与演替初期相比呈上升... 相似文献
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This study examines how biophysical site conditions differ in relation to the distribution of forest community types at Mount Kasigau, Kenya, in the Eastern Arc. Topographic measures of elevation, slope, curvature and aspect were derived from a 30‐m DEM and temperature and moisture conditions collected from 19 field data loggers for June 2011–2012 measured seasonal change along the steep elevational gradient (1000 m) from bushland to evergreen forest. Nonparametric statistical analyses then compared topographic and climatic conditions among eight ecologically classified forest types. Steep lapse rates in temperature and available moisture support abrupt changes in canopy physiognomy, but dew points declined with elevation. The Kruskal–Wallis test showed significant differences in the elevation, slope, temperature, dew point and relative humidity conditions among the eight forest types. These biophysical conditions are more discrete for Acacia‐Commiphora bushland and cloud forest but not significantly different between riverine forest, lower montane woodlands I and II and Euphorbia quinquecostata woodland, and between semi‐evergreen woodland and evergreen forest. Biophysical conditions and their influence on the distribution of forest types across a heterogeneous mountain landscape are important to understand and monitor in this unpredictably changing tropical seasonal climate. 相似文献
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CSR策略作为目前最流行的生态策略理论, 研究其沿环境梯度的变异规律有助于更好理解植物的生态适应策略。为探究黄土高原不同类型草地群落生态策略的变异规律, 以黄土高原中部3种不同类型草地植被带(森林草原、典型草原和荒漠草原)为研究对象, 沿水分梯度从东到西选择10个取样点, 每个取样点内设置8个1 m×1 m样方进行群落结构调查、叶片和吸收根关键功能性状的取样和测定, 根据“StrateFy”工具计算每个物种的CSR值, 并通过加权平均法(CWM)得到群落水平的CSR值, 分析CSR策略沿环境梯度的变化格局以及驱动因子。结果表明：(1)黄土高原中部不同植被带各群落内物种均以S策略为主。(2)水分梯度通过直接和间接影响叶面积来驱动群落水平CSR策略变异。(3)群落水平CSR策略与吸收根的CWM-RNC、CWM-RDMC显著相关, 但与吸收根的CWM-SRL、CWM-RD关系不显著。 相似文献
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叶片和根系是植物获取资源的最重要的器官,其性状随环境梯度的变化反映了植物光合碳获取和水分与养分的吸收能力及其对环境变化适应的生态对策。羌塘高原降水梯度带高寒草地群落叶片和根系成对性状关系研究不仅能揭示环境梯度对植物性状的塑造作用,也可为理解寒、旱和贫瘠等极端环境下植物的适应策略提供依据。为此,选择3组具有代表性的叶片和根系成对性状:比叶面积(SLA)和比根长(SRL);单位质量叶氮含量(LNmass)和单位质量根氮含量(RNmass);单位面积叶氮含量(LNarea)和单位长度根氮含量(RNlength),分析不同优势植物地上、地下成对性状变异特征及其与环境因子的关系,探讨植物性状对高寒生态系统水分和养分限制因素的适应策略。研究表明,区域气候和土壤环境导致的叶片性状变异大于根系性状的变异,干旱端的植物既具有高的SRL,又具有高的叶片和根系的养分含量(LNmass,LNarea和RNmass)。SLA-SRL、LNmass 相似文献
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Variation in leaf traits of dominant tree species in six montane rain forest communities was analyzed along an elevational gradient ranging from 1220 to 2560 m within a single basin at La Chinantla, Oaxaca, México. Three groups of characters were used: morphological (leaf shape, margin, blade configuration, and phyllotaxy), morphometric (leaf area, leaf mass per area, stomatal density, and blade length/width ratio), and anatomical (thicknesses of blade, palisade [PP], and spongy [SP] parenchymae, PP/SP ratio, and epidermis and cuticle thicknesses). The variation of morphological characteristics was only evident at the highest elevations; in contrast, thickness of leaf blade, PP, SP, as well as leaf mass per area clearly increased along the gradient, whereas leaf area was the only variable that significantly decreased with elevation. Thicknesses of epidermis and of the two cuticles were not significantly correlated with elevation. A classification analysis based on a leaf trait matrix led to the distinction between low and high elevation communities, with an approximate limit between them at ca 2300 to 2400 m. The results are discussed in light of environmental changes occurring along elevational gradients. Leaf characteristics of montane rain forest plants offer important insights about the complex roles of abiotic factors operating in these environments and supplement the traditional physiognomic classification schemes for these communities. 相似文献
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Eyvar E. Rodríguez-Quiel Glenda Mendieta-Leiva Maaike Y. Bader 《Journal of bryology》2019,41(2):95-106
Introduction. Tropical montane forests support a high abundance and diversity of bryophytes and lichens on different substrates. However, quantitative information about how their biomass and water-holding capacity change with elevation is scarce. The current project assessed variation in the biomass and water-holding capacity of bryophytes and lichens on Baru Volcano, Panama.
Methods. On the western slope, the bryophyte and lichen layer was collected from 600?cm2 plots on six substrate types with four replications at eight elevations along a gradient from 1900 to 3300?m a.s.l. We recorded the thickness, water-holding capacity and biomass of all samples, as well as environmental parameters.
Key results. At lower elevations substrates had a similar biomass and water-holding capacity per area, but with increasing elevation terricolous substrates showed the strongest increase (highest values at 3100?m). These patterns are associated with climatic variation along the gradient. At the highest elevations, the forest was of low stature and more light reached the forest floor. Also at these high elevations fog provides a daily wetting of the bryophytes and lichens. At lower elevations the water supply is increasingly in the form of rain, which is less frequent than the fog.
Conclusions. The apparent strong coupling of biomass variations to precipitation regimes implies a high sensitivity of the bryophytes and lichens to climatic warming and changes in the cloud base elevation. Furthermore our data suggest that the importance of bryophytes and lichens for regulating ecosystem water fluxes increases with elevation, which underlines the necessity to conserve intact montane forests. 相似文献
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Kauan Bassetto;Vítor Carvalho-Rocha;Carlos A. Peres;Selvino Neckel-Oliveira; 《Ecology and evolution》2024,14(12):e70624
Elevation gradients provide excellent semi-experimental conditions to investigate how the spatial distribution of biodiversity is shaped by the environment. Here, we investigate how temperature, productivity, and elevation are related to the diversity of anuran assemblages in a montane region of the southern Brazilian Atlantic Forest. We sampled 20 half-hectare plots between 2020 and 2021, distributed along a sharp elevation gradient. Anuran species richness and abundance decreased with increasing elevation. We show a positive relationship between ambient temperature and frog species richness and abundance, highlighting the importance of temperature in shaping assemblages along the elevation gradient. In contrast, productivity did not affect species richness and abundance, suggesting that available energy via resources does not limit local frog diversity. We further observed marked differences in the composition of anuran assemblages between low and high elevation areas, which were related to temperature. Beta diversity is mainly driven by species replacements among assemblages, which were likely related to environmental conditions. These findings highlight the importance of incorporating protected areas that encompass the entire range of elevations to capture the full complement of landscape-scale diversity. This is crucial as species showed limited distributions, and the marked effects of temperature should be explicitly considered under future scenarios of elevated upslope warming. 相似文献
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María Natalia Umaña Caicai Zhang Min Cao Luxiang Lin Nathan G. Swenson 《Ecology letters》2015,18(12):1329-1337
One of the few rules in ecology is that communities are composed of many rare and few common species. Trait‐based investigations of abundance distributions have generally focused on species‐mean trait values with mixed success. Here, using large tropical tree seedling datasets in China and Puerto Rico, we take an alternative approach that considers the magnitude of intraspecific variation in traits and growth as it relates to species abundance. We find that common species are less variable in their traits and growth. Common species also occupy core positions within community trait space indicating that they are finely tuned for the available conditions. Rare species are functionally peripheral and are likely transients struggling for success in the given environment. The work highlights the importance of considering intraspecific variation in trait‐based ecology and demonstrates asymmetry in the magnitude of intraspecific variation among species is critical for understanding of how traits are related to abundance. 相似文献
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Lianas are an important growthform in tropical forests, and liana abundance and biomass may be increasing in some regions. Explanations for liana proliferation hinge upon physiological responses to changing resource conditions that would favour them over trees. Testing a chemical basis for such responses, we assessed 22 foliar traits in 778 lianas and 6496 trees at 48 tropical forest sites. Growthform differences in chemical allocation occurred on a leaf mass and area basis. Light capture-growth and maintenance-metabolism chemicals averaged 14.5 and 16.7% higher mass-based concentration in lianas than in trees globally, whereas structure and defence chemicals averaged 9.0% lower in lianas. Relative differences in chemical allocation by lianas and trees were mediated by climate with peak differences at about 2500 mm year(-1) and 25 °C. Differences in chemical traits suggest that liana expansion could be greatest in forests undergoing increased canopy-level irradiance via disturbance and climate change. 相似文献
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Morphological variations of the Solidago virgaurea L. complex along an elevational gradient on Mt Norikura,central Japan 
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下载免费PDF全文 Morphological variations in vegetative and reproductive organs in the Solidago virgaurea complex were examined for eight elevations between 1600 and 2400 m a.s.l. in Japan. The rosette diameter and stem height were lower at higher elevations. The stem diameter at any stem height was greater at higher elevations, suggesting that the S. virgaurea complex increases mechanical stiffness against strong wind at high elevations. The number of flower heads at any stem height was less at high elevations (2000–2400 m a.s.l.) than at low elevations (1600–1900 m a.s.l.). Leaf nitrogen concentration did not change along the elevational gradient. Leaf mass per area (LMA) tended to decrease with increasing elevation, except for 2400 m a.s.l. The decrease of LMA would contribute to maintaining a positive carbon balance at high elevations. The number of involucral rays of flower heads was mostly four at low elevations (1600–1900 m a.s.l.) and three at high elevations (2000–2400 m a.s.l.). The number of involucral scales and diameter of flower heads were greater at high elevations (2000–2400 m a.s.l.) than at low elevations (1600–1900 m a.s.l.). Therefore, the S . virgaurea complex is suggested to adapt to high elevations that have cool temperature, a short growing season and strong wind conditions by changing its vegetative and reproductive traits. 相似文献
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Paul Chatelain Maxime Le Cesne Marianne Elias Eric Guilbert Adeline Soulier-Perkins 《Biotropica》2020,52(2):313-322
Along elevational gradients, phylogenetic relatedness patterns constitute a considerable source of information and may shed light on ecological processes that structure communities. This study focuses on community phylogenetic structure of planthoppers, specifically the species-rich and abundant Fulgoromorpha families (Hemiptera, Auchenorrhyncha), Cixiidae and Derbidae + Achilidae, along an elevational gradient on Mount Wilhelm (Papua New Guinea). In order to assess the factors driving planthoppers community composition, we recorded abundance data for planthoppers species at each elevation and we generated a molecular phylogeny of the local species, using Bayesian inference. We analyzed 168 individuals representing 59 local morphospecies. Using a fully resolved and well-supported phylogeny, we then investigated the phylogenetic structure of the communities by performing a Spatial Analysis of Community Diversity. We show that Cixiidae are phylogenetically clustered along the elevational gradient, whereas Derbidae + Achilidae harbor a random structure, suggesting that local adaptation to elevation shapes community structure of Cixiidae, but not that of Derbidae + Achilidae. Our findings highlight the importance of phylogenies in the study of tropical elevational gradients. 相似文献
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Altitudinal Change in LAI and Stand Leaf Biomass in Tropical Montane Forests: a Transect Study in Ecuador and a Pan-Tropical Meta-Analysis 总被引：1，自引：0，他引：1
Abstract
Leaf area index (LAI) is a key parameter controlling plant productivity and biogeochemical fluxes between vegetation and the
atmosphere. Tropical forests are thought to have comparably high LAIs; however, precise data are scarce and environmental
controls of leaf area in tropical forests are not understood. We studied LAI and stand leaf biomass by optical and leaf mass-related
approaches in five tropical montane forests along an elevational transect (1,050–3,060 m a.s.l.) in South Ecuador, and conducted
a meta-analysis of LAI and leaf biomass data from tropical montane forests around the globe. Study aims were (1) to assess
the applicability of indirect and direct approaches of LAI determination in tropical montane forests, (2) to analyze elevation
effects on leaf area, leaf mass, SLA, and leaf lifespan, and (3) to assess the possible consequences of leaf area change with
elevation for montane forest productivity. Indirect optical methods of LAI determination appeared to be less reliable in the
complex canopies than direct leaf mass-related approaches based on litter trapping and a thorough analysis of leaf lifespan.
LAI decreased by 40–60% between 1,000 and 3,000 m in the Ecuador transect and also in the pan-tropical data set. This decrease
indicates that canopy carbon gain, that is, carbon source strength, decreases with elevation in tropical montane forests.
Average SLA decreased from 88 to 61 cm2 g−1 whereas leaf lifespan increased from 16 to 25 mo between 1,050 and 3,060 m in the Ecuador transect. In contrast, stand leaf
biomass was much less influenced by elevation. We conclude that elevation has a large influence not only on the leaf traits
of trees but also on the LAI of tropical montane forests with soil N (nitrogen) supply presumably being the main controlling
factor. 相似文献
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J. Julio Camarero Emilia Gutiérrez Marie-Josée Fortin 《Global Ecology and Biogeography》2006,15(2):182-191
Aim To forecast the responses of alpine flora to the expected upward shift of treeline ecotones due to climatic warming, we investigated species richness patterns of vascular plants at small spatial scales across elevational transects.
Location Richness patterns were assessed at local scales along the elevational gradient in two undisturbed treeline ecotones and one disturbed treeline ecotone in the Spanish Pyrenees.
Methods We placed a rectangular plot (0.3–0.4 ha) in each treeline ecotone. We estimated and described the spatial patterns of plant richness using the point method and Moran's I correlograms. We delineated boundaries based on plant richness and tree cover using moving split windows and wavelet analysis. Then, to determine if floristic and tree cover boundaries were spatially related, overlap statistics were used.
Results Plant richness increased above the forest limit and was negatively related to tree cover in the undisturbed sites. The mean size of richness patches in one of these sites was 10–15 m. Moving split windows and wavelets detected the sharpest changes in plant richness above the forest limit at both undisturbed sites. Most tree cover and plant richness boundaries were not spatially related.
Main conclusions The upslope decrease of tree cover may explain the increase of plant richness across alpine treeline ecotones. However, the detection of abrupt richness boundaries well above the forest limit indicates the importance of local environmental heterogeneity to explain the patterns of plant richness at smaller scales. We found highly diverse microsites dominated by alpine species above the forest limit, which should be monitored to describe their response to the predicted upward shift of forests. 相似文献
Location Richness patterns were assessed at local scales along the elevational gradient in two undisturbed treeline ecotones and one disturbed treeline ecotone in the Spanish Pyrenees.
Methods We placed a rectangular plot (0.3–0.4 ha) in each treeline ecotone. We estimated and described the spatial patterns of plant richness using the point method and Moran's I correlograms. We delineated boundaries based on plant richness and tree cover using moving split windows and wavelet analysis. Then, to determine if floristic and tree cover boundaries were spatially related, overlap statistics were used.
Results Plant richness increased above the forest limit and was negatively related to tree cover in the undisturbed sites. The mean size of richness patches in one of these sites was 10–15 m. Moving split windows and wavelets detected the sharpest changes in plant richness above the forest limit at both undisturbed sites. Most tree cover and plant richness boundaries were not spatially related.
Main conclusions The upslope decrease of tree cover may explain the increase of plant richness across alpine treeline ecotones. However, the detection of abrupt richness boundaries well above the forest limit indicates the importance of local environmental heterogeneity to explain the patterns of plant richness at smaller scales. We found highly diverse microsites dominated by alpine species above the forest limit, which should be monitored to describe their response to the predicted upward shift of forests. 相似文献