Edinburgh Journal of Botany 

About: Edinburgh Journal of Botany is an academic journal published by Royal Botanic Garden Edinburgh. The journal publishes majorly in the area(s): Genus & Gesneriaceae. It has an ISSN identifier of 0960-4286. Over the lifetime, 835 publications have been published receiving 9456 citations.

Analysis of the floristic composition of the Brazilian cerrado vegetation II: Comparison of the woody vegetation of 98 areas

Abstract: An analysis was made of the floristic composition of 98 areas of cerrado and Amazonian savanna, encompassing most of the area of such vegetation in Brazil. A total of 534 species of trees and large shrubs were recorded for these areas, of which 158 (30%) occurred at a single site only. Such unicates and taxa without determinations to specific level were excluded from the study since they provide no basis for comparison. The data were analysed by three techniques of multivariate analysis: (a) a divisive hierarchical classification by Two-way Indicator Species Analysis (TWINSPAN). (b) an agglomerative hierarchical classification by UPGMA (Unweighted Pair-Groups Method using Arithmetic Averages) using the Sorensen Coefficient of Community (CC) as a measure of similarity, and (c) an ordination by Detrended Correspondence Analysis (DCA). The results from all three methods showed great similarity, demonstrating a strong geographic pattern in the distribution of the flora of the cerrado biome and allowing the recognition of southern (Sâo Paulo and S Minas Gerais), southeastern (largely Minas Gerais), central (Federal District, Goias and parts of Minas Gerais), central-western (largely Mato Grosso, Goias and Mato Grosso do Sul) and northern groups (principally Maranhao, Tocantins and Para), as well as a disjunct group of Amazonian savannas. Soil type (mesotrophic or dystrophic) is an important factor in determining floristic composition. The study demonstrated that cerrado vegetation is extremely heterogeneous: none of the 534 species occurred at all sites and only 28 species were present at 50% or more.

A study of the origin of central Brazilian forests by the analysis of plant species distribution patterns

Abstract: The floristic nature of central Brazilian forests, as well as their links to other main forest formations of eastern tropical South America, is assessed by means of multivariate analyses of 106 existing floristic checklists and by the analysis of a series of dot-maps showing the distribution of 55 woody species. Most species of central Brazilian forests seem to conform to two main distribution patterns: (1) species of deciduous and semideciduous forests are dependent essentially on the occurrence of patches of soils of intermediate to high fertility within the cerrado domain and tend to be distributed mostly along a northeast-southwest arch connecting the caatingas to the chaco boundaries; (2) considerable numbers of gallery forest species are dependent on high soil moisture and many appear to link the Amazonian and Atlantic rainforests by crossing the cerrado region in a northwest-southeast route via the dendritic net of gallery forests. Many gallery forest species are habitat generalists, some even occurring in the cerrado vegetation. Nevertheless, significant numbers of gallery endemics are also present. Galleries of the west and north of the Cerrado Province show stronger floristic links to the Amazonian rainforests, while those of the centre and south show stronger affinity with the montane semideciduous forests of southeastern Brazil. Present-day distribution patterns are discussed in the light of the current knowledge of palaeoenvironmental changes in the Neotropics.

Seasonally dry forests of tropical south america: from forgotten ecosystems to a new phytogeographic unit

Abstract: The Pleistocenic Arc, which must have originated from the climatic shifts in South America during the late Pleistocene, ranges from the Caatingas of north-eastern Brazil through south-eastern Brazil to the Paraguay and Parana rivers confluence, into south-western Bolivia and north-western Argentina, and extends sporadically into dry Andean valleys of Peru or coastal western Ecuador. It is regarded as a new phytogeographic unit for South America, here named the Tropical Seasonal Forests Region, as it is characterized by a considerable number of endemic plant taxa at both generic and species level. The paradigm of the arc is the distribution pattern of Anadenanthera colubrina (Fabaceae), which, when superimposed on those of other woody species of seasonal forests, permits a reasonably accurate mapping of the new region, which might also have biogeographic implications for endemic bird taxa. The plant communities of this newly recognized unit are unique in their nature and floristic composition, when compared with other floristic areas of the continent by means of classic phytosociological and numerical analyses (PCA). These ecosystems have remained submerged within other vegetation units in South American phytogeography (such as the Chaquenian or Amazonian regions), and have been particularly neglected in conservation policies. An urgent call is made for these areas to be preserved before they disappear, because they are located in areas with some of the best agricultural soils of tropical South America, and therefore subject to clearing for farming.

Phylogeny and classification of the marchantiophyta

Abstract: Input from molecular phylogenetics in the past five years has substantially altered concepts of systematic relationships among liverworts. While these studies have confirmed the monophyly of phylum Marchantiophyta, they have demonstrated that many previously recognised ranks within the hierarchy are unnatural and in need of modification. Changes in the ranks of suborder and above have been proposed by various workers, but modifications in the circumscription of genera and families are still required. A comprehensive, phylogenetic classification scheme that integrates morphological data with molecular hypotheses is presented. The scheme includes diagnoses and publication citations for all names above the rank of genus. All currently recognised genera are listed alphabetically in their respective families; subfamilies are not indicated. Major modifications and novel alignments of taxa are thoroughly discussed, with pertinent references provided. Jungermanniaceae is redefined and Solenostomataceae fam. nov. is formally described to accommodate some of the genera excluded from it.

Successional changes in cerrado and cerrado/forest ecotonal vegetation in western são paulo state, brazil, 1962–2000

Abstract: Surveys over a period of 38 years have shown a rapid successional change in the remaining areas of cerrado vegetation in western Sao Paulo State Cerradao (the dense, tall, forest form of cerrado (sensu lato)) and cerrado/Atlantic forest ecotonal vegetation have replaced more open forms (such as campo cerrado) during this period An aerial photographic survey in 1962 showed 75% cerrado (sensu stricto), 16% campo cerrado, and only 9% cerradao, while a survey combining Landsat imaging of 1992 with aerial photography of 1984 gave 69%, 06%, and 305% respectively for the same physiognomies Visiting 10% of the sites of the latter survey in 2000 showed that cerradao had become the dominant vegetation of 68% of them In a particular 180 ha site in Assis municipality, cerradao increased from 120 to 414% of the area in 22 years Reduction of anthropic pressures, such as fire and cattle-grazing, is considered responsible for these rapid changes Conservation issues and research priorities related to these changes are discussed and proposed