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Johnson, Leigh - - 2012
Amphitropical disjunct distributions between western North America and western South America have intrigued botanists for over a century. Here, specific examples of migration and speciation are investigated using herbaceous species from the phlox family (Polemoniaceae) as a model for considering the timing of dispersal relative to speciation. Comparative DNA sequencing ...
Carpenter, Raymond - - 2012
Foliar fossils of Proteaceae are reviewed, and useful specimens for interpreting evolution, and past and present distributions and environments are discussed. There are no definite Cretaceous occurrences. However, there is evidence of extant lineages dating from the Paleocene onwards, including tribe Persoonieae of subfamily Persoonioideae and each of the four ...
Lee, Daphne - - 2012
The modern New Zealand flora has a relatively low number of families and genera in relation to land area, but well-preserved macrofossils and pollen from three sites in southern New Zealand suggest that the floras in Eocene, Oligocene and Miocene times were much more diverse at the generic level. At ...
Futey, Mary - - 2012
We describe fossil fruits collected from outcrops of the Salamanca Fm. (Paleocene, Danian, 63.3-61.9 Ma) at the Estancia Las Violetas locality, Chubut, Argentina that show affinities with members of the Subtribe Attaleinae, Tribe Cocoseae, Subfamily Arecoideae within the Arecaceae. The fossils are preserved as permineralizations, and were examined by longitudinal, ...
Reutemann, Andrea - - 2012
This work presents the basics for interpreting the adult inflorescence structure in Cyperaceae. It provides an analysis of the variations of the synflorescence and inflorescence structure in the family. Three types of synflorescence may be recognized in this family: a synflorescence with a foliate stem, a terminal inflorescence and a ...
Olson, Mark - - 2012
For nearly a century the so-called Major Trends of Xylem Evolution have guided thinking regarding wood evolution, but their conceptual foundations have not been examined. I detail and critique nine tenets of Major Trends thinking, including the use of linear schemes to infer phylogeny, the Haeckelian assumption that ontogeny recapitulates ...
Carlquist, Sherwin - - 2012
Five sources of data force extensive revision of ideas about the nature and evolution of monocot xylem: scanning electron microscopy (SEM) studies of thick sections; availability of molecular phylogenies covering a relatively large number of families and genera; information on ecology and habitat; data concerning habit; and observations from xylem ...
Sinclair, Jordan - - 2012
This paper examines the history of sex ratio theory and the effects of multiple variables on individual and population sex ratios. It also provides examples where plants have been used to test major predictions of sex ratio theory. Then, using over 200 studies from the literature, dioecious plant species are ...
Seth, Chandra - - 2012
This article deals with the advances and implication of phytoremediation technologies with emphasis on remediation of toxic heavy metals from contaminated soil. Most of the conventional remedial technologies are expensive and inhibit the soil fertility and cause negative impacts on various ecosystem services. However, phytoremediation is a cost effective and ...
Vander Wall, Stephen - - 2012
Frugivory (animals ingest all or part of fleshy-fruits and defecate or regurgitate seeds) and scatter-hoarding (animals store seeds in small caches in soil) are two important vertebrate-mediated seed dispersal syndromes. In both instances, there is an exchange of food for seed transport, but there are many important differences. For example, ...
Myster, Randall - - 2012
Over the past few decades, several conceptual and mathematical models of plant community organization and dynamics have been put forward. While each of these models has attempted to explain important plant community patterns by attributing them to some aspect of plant niches, or to a higher-level process, their predictive success ...
Bernal, Rodrigo - - 2011
We reviewed information on management of useful palms in South America. We documented management for 96 species, from incidental activities intended to increase populations of wild palms to the inclusion of palms in complex agroforestry systems. Two species, Bactris gasipaes and Parajubaea cocoides, are domesticated. Managed species are remarkably fewer ...
Brokamp, Grischa - - 2011
More than 200 scientific publications and Internet sources dealing with trade in palm products in north-western South America are reviewed. We focus on value chains, trade volumes, prices, and recent developments for some of the most important raw materials derived from native palms. Trade in palm products takes place at ...
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Macia, Manuel - - 2011
A thorough review concerning palm uses in tropical rainforests of northwestern South America was carried out to understand patterns of palm use throughout ecoregions (Amazonia, Andes, Choco), countries (Colombia, Ecuador, Peru, Bolivia), and among the different human groups (indigenous, mestizos, afroamericans, colonos) that occur there. A total of 194 useful ...
Balslev, Henrik - - 2011
To advance our understanding of the processes that govern the assembly of palm communities and the local coexistence of numerous palm species, we here synthesize available information in the literature on species diversity and growth-form composition in palm communities across the Americas. American palm communities surveyed had 4-48 (median 16) ...
Balslev, Henrik - - 2011
Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants in tropical American forests. ...
de la Torre, - - 2011
Non-timber forest products (NTFPs) derived from palms and other plants are economically and culturally important to a large part of the more than 240 million people who live in the forest areas of developing countries. The sustainable extraction of NTFPs is increasingly regarded as an important part for forest conservation ...
Liu, Juan - - 2011
To evaluate the effect of land use change from a natural broadleaf evergreen forest to Moso bamboo plantations and their management practices on soil [N.sub.2]O efflux in a subtropical region of China, [N.sub.2]O efflux was measured during June 2008 and May 2009 using static closed chamber method. The observed mean ...
Qin, Hua - - 2011
High rate of fertilization and heavy winter mulch have been a common practice to gain a good yield in Phyllostachys praecox stands, but the long-term impact of this intensive management on soil ammonia-oxidizing bacteria (AOB) is largely unknown. Population size of soil AOB was quantified by real-time PCR in Phyllostachys ...
Jin, Aiwu - - 2011
The changes of leaf area index (LAI), leaf photosynthetic pigment content, photosynthetic rate of Phyllostachys pubescens in one leaf development cycle (two years) under different fertilization (no fertilization: CK, fertilization at the leave-expansion period: T1, fertilization at the end of August: T2) were studied. The bamboo showed a high LAI ...
Zhou, Guomo - - 2011
Area of bamboo forest (Phyllostachys praecox) has rapidly increased in southern China during the last 20 years due to its high economic value. Aims of this study were to analyse the temporal and spatial variations of soil organic matter (SOM) in heavily winter mulched bamboo stands and to estimate potential ...
Xu, Yong - - 2011
Moso bamboo (Phyllostachys pubescens) has an extremely fast growth rate, however little information is available on the dynamics of carbon accumulation during the fast growth period. Bamboo trunk were sampled at three different stages (1: shoot emergence to first shell detachment; 2: first shell detachment to branch emergence; 3: branch ...
Li, Yongfu - - 2011
Moso bamboo (Phyllostachys pubescens) is an important non-timber forest product (NTFP) in the forest ecological system of subtropical China. In this study of young bamboo, dynamic changes in height, biomass, and carbon accumulation were determined and tissue samples were analyzed by [sup.13]C-nuclear magnetic resonance (NMR) technology. Results showed that the ...
Wen, Guosheng - - 2011
To study the temporal and spatial dynamics of carbon fixation by Moso bamboo (Phyllostachys pubescens) in subtropical China, carbon fixation of leaves within the canopy of P. pubescens was measured with a LI-6400 portable photosynthesis system. The results showed that the capability of carbon fixation of P. pubescens leaves had ...
Zhou, Guomo - - 2011
Bamboo is widespread in the subtropics and tropics of Asia, Africa, and Latin America. The total area of bamboo forests of various species is 22.0 x [10.sup.6] ha, accounting for about 1.0% of the total global area of forest. Although the total forest areas in many countries have decreased drastically, ...
Zhuang, Shunyao - - 2011
Carbon sequestration in soils is considered to be an important option for the mitigation of increasing atmospheric C[O.sub.2] concentrations as a result of climate change. High carbon accumulation was observed in Lei bamboo (Phyllostachys praecox) soils when using large amounts of organic material in a mulching technique. Soil samples were ...
Jiang, Pekun - - 2011
Selection and development of tree species with high fixing C[O.sub.2] capacity is an increasing problem worldwide. A comparative study on carbon fixation ability of three forest stands was conducted at Linlong Mountain, Li'nan County, Zhejiang Province, China. The results showed that total carbon storage in the ecosystems of Moso bamboo, ...
Zhou, Mingbing - - 2011
In Gramineae plants, carbon sequestration is closely related to the internodes development which is regulated by the gibberellins (GAs). Chitininducible gibberellin-responsive genes (CICR) are a member of the GRAS superfamily involved in the gibberellin signal transduction pathway and play roles in the development and defense of the plant. In this ...
Lin, Xinchun - - 2011
Bamboo is one of the most important forest resources with a strong carbon fixation capability. To utilize genetic resource of Phyllostachys violascens, ISSR (inter-simple sequence repeat), SRAP (sequence-related amplified polymorphism), and AFLP (amplified fragment length polymorphism) techniques were used for the first time for the assessment of genetic diversity within ...
Renyi, Gui - - 2011
Moso bamboo (Phyllostachys pubescens) is widely distributed in the acid soil region of Southern China, where great potential of aluminum (Al) toxicity exists. To evaluate the Al tolerance of Moso bamboo, seed germination and root elongation were compared with two rice cultivars, and physical and physiological damages were examined under ...
Song, Zhaoliang - - 2011
C[O.sub.2] consumption by silicate weathering has exerted a major control on atmospheric C[O.sub.2] over geologic time. In order to assess plant impact on this process, the study compared water geochemistry and C[O.sub.2] consumption rates by silicate weathering in watersheds covered by bamboos and other forests. Our study showed that Si[O.sub.2] ...
Hong, Chuntao - - 2011
Bamboo and Miscanthus species are perennial low-input plants that are excellent candidates for bioenergy feedstock production. Biological characteristics, dry matter yields and fuel properties of the bamboo and Miscanthus have been studied. Genotype growth characteristics were determined by measurements of plant height, tillering, tuft diameter, and shoot diameter. To date, ...
Cao, Zhihong - - 2011
Net photosynthetic rate (Pn) increased in bamboo (Phyllostachy pubescens) with increased atmospheric C[O.sub.2] concentrations. Average maximum Pn was 17.76, 16.66, and 16.77 ([micro]mol/[m.sup.2]/s) in lower, middle and upper layers canopy respectively at C[O.sub.2] saturation point. Light use efficiency of leaves ranged from 0.15% to 2.25% on different days and at ...
Shahri, Waseem - - 2011
Different strategies of petal senescence and some important events associated with it have been discussed. On the basis of sensitivity to ethylene and associated symptoms of senescence, petal senescence has been classified into five different classes; besides changes in membrane permeability, autophagy and involvement of VPEs (Vacuolar processing enzymes), degradation ...
Zotz, Gerhard - - 2011
Virtually all plants show a certain degree of variation among individual metamers during ontogeny. In some cases, however, there are abrupt and substantial changes in form and function (e.g. in leaf form, leaf size, phyllotaxy, internode length, anthocyanin pigmentation, rooting ability, or wood structure). These plants were called "heteroblastic" by ...
Sklenar, Petr - - 2011
Biogeography of the tropical alpine flora of South and Central America, the paramo flora, has been studied by dividing genera into tropical, temperate, and cosmopolitan chorological flora elements. Published molecular phylogenies of paramo genera are reviewed to summarize knowledge about evolutionary history of the paramo flora and to assess congruence ...
Mattio, Lydiane - - 2011
Sargassum C. Agardh is one of the morphologically most complex phaeophyceaen genera and represents the most species-rich genus of the brown algal order Fucales Bory de Saint-Vincent (Phaeophyceae). The genus' classification system dates back to the 19th century and is based on observed differences in macromorphological characters. Those morphological characters ...
Paul, Gillian - - 2011
The climbing habit has evolved independently in many plant taxa, offering vines the ability to compete with non-climbing vegetation for resources such as light, nutrients, and water. This review examines the structural and functional characteristics that allow climbing plants to (1) achieve widespread dispersal, (2) transport large amounts of water ...
Robbertse, Hannes - - 2011
In the literature there is disagreement about the existence of a coleorhiza in cycad embryos. In this paper the terminology of the cycad ovule, seed and embryo is revised. It was confirmed that the cycad ovule and seed are pachychalazal and that the seed coat is exclusively formed by the ...
Dulin, Max - - 2010
The related concepts of paedomorphosis in the secondary xylem, insular woodiness, and secondary woodiness are reviewed and evaluated in order to clearly distinguish the phenomenon involved, and provide a firm foundation for future research in this area. The theory of paedomorphosis refers to the occurrence of certain juvenile xylem characteristics, ...
Segui-Simarro, Jose - - 2010
Androgenesis can be defined as the set of biological processes leading to an individual genetically coming exclusively from a male nucleus. Androgenesis was traditionally considered as the spontaneous, in vivo development of a male-derived haploid embryo from a fertilized egg where the female nucleus is eliminated. However, at present it ...
Francisco-Ortega, Javier - - 2010
Hainan, the second largest island of China, has the most extensive and best preserved tropical forests of this country. A network of 68 protected areas (54 of them are terrestrial) provides in situ conservation for the unique ecosystems of the island. We: (1) discuss an updated check-list of seed-plant species ...
Francisco-Ortega, Javier - - 2010
Global conservation of plant biodiversity on tropical islands is a major priority, as approximately one third of all endangered plant species are insular endemics. Checklists can be an important first step in determining conservation priorities on islands. Hainan, the largest island in the Indo-Burma Biodiversity Hotspot, and therefore an international ...
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