Abstract:
:Size, allometry, and mechanical design were measured for trees of three canopy species in a tropical rain forest in French Guiana. Mechanical design was expressed as the safety factor, using the elastic-stability model, and the wind resistance factor, using the constant-stress model. Changes with ontogeny were described as regressions using stem diameter as the independent variable, and they were compared between species. Height, crown size, and the wind resistance factor increased with ontogeny. The safety factor decreased to a minimum and then increased continuously in thicker trees. The crown width/height ratio did not change with ontogeny. Interspecific differences in allometry and mechanical design were related to the adult stature of the species, and not to shade tolerance. The short stature species (Vouacapoua americana) was less slender (height:DBH [stem diameter at 1.3 m] ratio) and had a higher crown width/height ratio than the tall stature species (Goupia glabra and Dicorynia guianensis). Vouacapoua had a higher safety factor, but a similar wind resistance factor. The safety factors of our study species were lower than those of two temperate tree species because of a higher slenderness. Differences in safety factors between tropical and temperate trees may result from unrealistic assumptions of the elastic-stability model, and may also be related to lower light levels and-or wind rates in the tropics.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Sterck F,Bongers Fsubject
Has Abstractpub_date
1998-02-01 00:00:00pages
266issue
2eissn
0002-9122issn
1537-2197pii
85/2/266journal_volume
85pub_type
杂志文章abstract:PREMISE OF THE STUDY:Male-biased herbivory in dioecious species is expected as a consequence of selection for increased resistance (reduced attack) in the sex with higher reproductive costs-females. Empirical support of this prediction is taxonomically restricted and fraught with exceptions. Phenological changes in res...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200603
更新日期:2013-02-01 00:00:00
abstract::Herbivore damage is known to cause the premature loss of mature leaves. However, the effects of herbivory on abscission during the early stages of leaf development remain unexplored, even though herbivores frequently prefer unlignified, immature leaves. In a field experiment, we removed 50% of the tissue from leaves a...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-11-01 00:00:00
abstract:PREMISE OF THE STUDY:The study of scaling examines the relative dimensions of diverse organismal traits. Understanding whether global scaling patterns are paralleled within species is key to identify causal factors of universal scaling. I examined whether the foliage-stem (Corner's rules), the leaf size-number, and the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500439
更新日期:2016-05-01 00:00:00
abstract:PREMISE OF THE STUDY:The correct assessment of homology is an important prerequisite for reconstructing phylogenetic relationships and character evolution. Old World Papaveroideae (Papaver, Meconopsis, Roemeria, Stylomecon) show substantial diversity in gynoecium and capsule morphology. In particular, capsules can have...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100066
更新日期:2011-08-01 00:00:00
abstract::Long-distance transplantation of seed material as done in restoration programs has raised concerns about the risks associated with the introduction of maladapted genotypes that may hybridize with neighboring native conspecifics and decrease local population fitness (outbreeding depression). We studied the consequences...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900103
更新日期:2010-01-01 00:00:00
abstract::Interspecific hybridization is considered a possible mechanism of plant diversification. The Andes are a hotspot of biodiversity, but hybridization in Andean taxa has so far not been investigated intensively. The current study investigates crossability in Caiophora (Loasaceae subfam. Loasoideae) by experimental inters...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.2007403
更新日期:2008-09-01 00:00:00
abstract::Patterns of biodiversity are ultimately the product of speciation and extinction. Speciation serves as the biodiversity pump while extinction serves as the agent that culls global to local levels of biodiversity. Linking these central processes to global and local patterns of biodiversity is a key challenge in both ec...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1000289
更新日期:2011-03-01 00:00:00
abstract::This study shows that structural data, when carefully examined, can provide valuable characters for delimiting monophyletic groups and can complement DNA with observable features to recognize and circumscribe taxa. In the angiosperm order Apiales, traditional classification has relied heavily (often exclusively) on fr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.9.1357
更新日期:2006-09-01 00:00:00
abstract::Koch et al. (Nature 428: 851-854) measured various parameters that were thought to limit the height of Sequoia sempervirens from northern California and concluded that the maximum height for this species is 122-130 m because within this range: (1) Irreversible embolism formation was proposed to occur when the xylem pr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800144
更新日期:2009-02-01 00:00:00
abstract:PREMISE OF THE STUDY:This paper investigates the occurrence and evolution of aluminum (Al) accumulation within ferns and lycophytes, which is characterized by Al concentrations above 1000 mg·kg-1 in aboveground plant tissues. We hypothesize that this feature is more common in ferns than in angiosperms, and potentially ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600381
更新日期:2017-04-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite markers were isolated and characterized from Dacryodes edulis (Burseraceae), a tropical rainforests fruit tree of central Africa. METHODS AND RESULTS:Using an enrichment protocol, six microsatellites loci were developed from Dacryodes edulis. We investigated polymorphism using 45 tr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000463
更新日期:2011-04-01 00:00:00
abstract::Eight ecosystems that were present in the Cretaceous about 100 Ma (million years ago) in the New World eventually developed into the 12 recognized for the modern Earth. Among the forcing mechanisms that drove biotic change during this interval was a decline in global temperatures toward the end of the Cretaceous, augm...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1000353
更新日期:2011-03-01 00:00:00
abstract:PREMISE:Outcomes of species interactions, especially mutualisms, are notoriously dependent on environmental context, and environments are changing rapidly. Studies have investigated how mutualisms respond to or ameliorate anthropogenic environmental changes, but most have focused on nutrient pollution or climate change...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1404
更新日期:2020-02-01 00:00:00
abstract::Hybridization and introgression play important roles in plant evolution, and their occurrence on the oceanic islands provides good examples of plant speciation and diversification. Restriction fragment length polymorphisms (RFLPs) and trnL (UAA) 3'exon-trnF (GAA) intergenic spacer (IGS) sequences of chloroplast DNA (c...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-06-01 00:00:00
abstract::Chloroplast DNA (cpDNA) is maternally inherited in the majority, but not all, of angiosperm species. The mode of inheritance of cpDNA is a critical determinant of its molecular evolution and of its population genetic structure. Here, we present the results of investigations of the inheritance of cpDNA in Silene vulgar...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.8.1333
更新日期:2007-08-01 00:00:00
abstract::Seed size and germination requirements of eight (of nine) Sarracenia species, and 13 populations of S. purpurea were studied. All species except for S. purpurea are restricted to the southeastern United States, whereas S. purpurea ranges across Canada, southward along the eastern United States into Maryland and Virgin...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-03-01 00:00:00
abstract:PREMISE OF THE STUDY:Giant cacti species possess long cylindrical stems that store massive amounts of water and other resources to draw on for photosynthesis, growth, and reproduction during hot and dry conditions. Across all giant cacti taxa, stem photosynthetic surface area to volume ratio (S:V) varies by several fol...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1166
更新日期:2018-10-01 00:00:00
abstract::We assessed the effects of local environment on survival, growth, and development in six clones (genotypes) of Vallisneria americana grown at five sites in the Huron-Erie Corridor. Detrimental effects of local environment on plant performance (rate of clonal growth, leaf and root production, surface area of leaves and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
abstract:PREMISE OF THE STUDY:Bignoniaceae is an important component of neotropical forests and a model for evolutionary and biogeographical studies. A previous combination of molecular markers and morphological traits improved the phylogeny of the group. Here we demonstrate the value of next-generation sequencing (NGS) to asse...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1700302
更新日期:2017-10-01 00:00:00
abstract::Evolutionary relationships among representatives of Apiaceae (Umbelliferae) subfamily Apioideae have been inferred from phylogenetic analyses of nuclear ribosomal DNA internal transcribed spacer (ITS 1 and ITS 2) and plastid rpoC1 intron sequences. High levels of nucleotide sequence variation preclude the use of the I...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-04-01 00:00:00
abstract:PREMISE OF THE STUDY:Within the Hypnales-the most derived and species-rich order of pleurocarpous mosses - phylogenies at or below the family level often show poor resolution. In preparation for a phylogeny of the genus Plagiothecium, we wished to identify the DNA markers best suited for evolutionary reconstruction in ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300269
更新日期:2014-04-01 00:00:00
abstract:PREMISE:Inbreeding depression is traditionally considered a major factor favoring outcrossing in hermaphrodites. Recent experiments have shown that environmental conditions can influence the magnitude of inbreeding depression, but their relevance in natural populations is unclear. To investigate this, we studied the cl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1410
更新日期:2020-01-01 00:00:00
abstract::Nuclear and chloroplast DNA variation was assayed for two populations of Louisiana irises (Bayou Teche and Young's Coulee) that demonstrated extreme morphological variation and for a sample of the putative hybrid species, Iris nelsonii. The genetic markers examined in this analysis were diagnostic for either Iris fulv...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1993.tb13843.x
更新日期:1993-05-01 00:00:00
abstract:PREMISE OF THE STUDY:Direct tests of a species distribution model (SDM) were used to evaluate the hypothesis that the northern and southern edges of Mimulus bicolor's geographical range are limited by temperature and precipitation. METHODS:Climatic suitability was predicted using an SDM informed only by temperature an...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600414
更新日期:2017-06-01 00:00:00
abstract::The specific shape of the relationship between plant diversity and productivity and the causal mechanism(s) behind the observed pattern(s) are still highly debated. Recent advances suggest that the relationship depends on several environmental variables and may change with the observational scale. In this study, a mul...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.1.79
更新日期:2007-01-01 00:00:00
abstract::In a recent study (American Journal of Botany 97: 730-737), we described the first case of a tripartite association in natural conditions among a holoparasitic plant (Cytinus), its host Cistaceae species, and mycorrhizal fungi at an anatomical level. In a letter to the editor, Brundrett (American Journal of Botany 98:...
journal_title:American journal of botany
pub_type: 评论,杂志文章
doi:10.3732/ajb.1100036
更新日期:2011-04-01 00:00:00
abstract::For more than a century, the common ancestor of flowering plants was thought to have had a seven-celled, eight-nucleate Polygonum-type female gametophyte. It is now evident that not one, but in fact three, patterns of female gametophyte development and mature structure characterize the common ancestors of the four mos...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800311
更新日期:2009-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Fern spores are unicellular and haploid, making them a potential model system to study factors that regulate lifespan and mechanisms of aging. Aging rates of nongreen spores were measured to compare longevity characteristics among diverse fern species and test for orthodox response to storage tempe...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100257
更新日期:2012-04-01 00:00:00
abstract::We analyzed the effects of temporal variation in floral display size (number of flowers open at one time on a plant) on the rate of pollen removed and receipt of individual flowers for the sequential blooming plant Narthecium asiaticum (Liliaceae). Because of the acropetal blooming of this species, the display sizes w...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.3.441
更新日期:2002-03-01 00:00:00
abstract::The last decade has witnessed a resurgence in the study of the evolution of plant development, combining investigations in systematics, developmental morphology, molecular developmental genetics, and molecular evolution. The integration of phylogenetic studies, structural analyses of fossil and extant taxa, and molecu...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.10.1726
更新日期:2004-10-01 00:00:00