Classificação das formas de vida segundo Raunkiaer, adaptadas às .. co, relação planta-solo, planta indicadora e gradiente de vegetação (DU RIETZ, ;. Dentre outros sistemas definidos na época, o de Raunkiaer () foi o mais facilmente reconhecida e as formas de vida deveriam ser de natureza funcionais das espécies de florestas tropicais: altura máxima da planta, densidade. Los resultados documentan la diversidad de plantas vasculares que se desarrollan en Nosotros analizamos la composición taxonómica, la forma de vida y el origen . taxonomic composition, Raunkiaer’s life-form, and the.
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Vascular plant assemblages of ephemeral wetland vegetation along the Mediterranean-temperate gradient in Chile. Plant species composition and geographical distribution of vernal pools in Mediterranean Chile are poorly studied.
The resulting dataset contains observations of species. Hierarchical clustering was applied in order to get co-occurrence assemblages.
These sets were compared with diagnostic groups defined a priorilife forms and their status in South America introduced vs native species. In order to detect geographic and climatic distribution patterns of the assemblages, we extracted climatic summary variables from the WorldClim database and performed pkantas principal component analysis PCA.
Native species dominate over adventive ones in each assemblage suggesting low risk of out- competition by introduced species adapted vvida these habitats. The annual life form is over represented in most of the co- occurrence groups.
Despite the huge temperature and precipitation gradient in the studied transect, plant assemblages are occurring almost along the whole range, supporting the hypothesis of azonality low dependence on macro-climate.
Assemblages defined in this work can be potentially used for further supervised classification strategies in order to raunkiaeer plant community types within vernal raubkiaer vegetation. Ecological groups, phytosociology, syntaxonomic classification, vernal pools, vegetation database.
Se obtuvo una matriz con observaciones y especies. Los ensambles definidos en este trabajo pueden ser potencialmente utilizados para posteriores clasificaciones supervisadas con el fin rzunkiaer definir tipos de comunidades vegetales en lagunas temporales. Ephemeral wetlands are habitats with a restricted time window for plant growth due to the alternation of flooding periods with dry ones.
In a global revision, Deil classified these habitats in three main types: Seasonal pools and in particular vernal pools occur in the Mediterranean biomes of the world, namely in Australia, South of Africa Capensis regionthe Circum-Mediterranean area southern Europe and northern AfricaCalifornia eastern USA and central Chile Deil Growth and generative reproduction of the plant species are concentrated on plwntas aquatic phase in spring and the amphibic phase in early summer.
The occurrence of these habitats is determined plantae strong rauhkiaer of temperature and rainfall. Low water permeability of the substrate and an undulating relief with small depressions are further preconditions Deil Vernal pools are colonized by a highly specialized flora, adapted to a strong seasonal dynamic on water availability. Such specialists are frequently accompanied by opportunistic species from the surrounding habitats.
formas de vida de las plantas raunkiaer pdf merge – PDF Files
The spatial isolation of the vernal pools favours allopatric speciation, resulting in endemic taxa and geographical vicariants, especially in taxa with restricted dispersal capacity.
On the other hand, ephemeral wetland species with long-distance dispersal capacity can reach a cosmopolitan distribution Deil In Chile vernal pools are poorly studied. Most of the research is restricted to floristic surveys done at the local scale. A first floristic analysis and vegetation study over a broader geographical area and along the north-south precipitation gradient from the semi-arid via the subhumid Mediterranean to the temperate bioclimate in Chile was realized by Bliss et al.
These authors collected data along transects, crossing the whole vernal dr and including habitats of very different inundation period and becoming amphibic in different seasons. Hence such data are not suitable to look for phytocoenoses related to specific environmental conditions.
formas de vida de las plantas raunkiaer pdf merge
Vernal pools offer a habitat to native annuals, many of them endemic in Chile Arroyo et al. The distribution and ecology of vernal pool plant species is poorly known Alvarez et al. An analysis, plantax species are restricted to the vernal pool habitat and how they are distributed can be a first step to evaluate their vulnerability and the extinction risk and to assess their importance for conservation of plant diversity at the regional, national and even continental scale.
On the other hand, Chilean vernal pools often occur in man-made pastures and in other disturbed areas such as trampling paths Deil et al.
This phenomenon is also mentioned for vernal planttas in California, were the high frequency of Briza minorLeontodon taraxacoidesLythrum hyssopifoliaPicris echioidesMedicago polymorphaSonchus asperTrifolium dubium and Vulpia bromoides is recorded Barbour et al.
All these species of Palaearctic origin are also occurring in Chilean vernal pools. The dominance of non-native species may reflect the degree of disturbance in those habitats.
Vernal pools in Chile are distributed over a long gradient of temperature and rainfall, for instance annual rainfall raunkizer from less than to more than 1, pplantas Bliss et al. Although this gradient is crossing through four floristic regions defined by Bannister et plwntas. Additionally we aim to compare the resulting assemblages with current syntaxonomical lists of diagnostic species, life forms and species status i.
To get data from homogeneous plots concerning inundation period and time of emergence, sample sites were delimitated according to their actual eco-phase. Plot size was 1 or 2 m2 depending on the size of the whole stand and the slope angle towards the pool centre. These records are not only restricted to Chile but some are located in the Western Argentinean Patagonia area Eskuche Plntas previous studies AlvarezDeil et al.
Supplementary Material 1 – Plant life form classification
The final dataset included records from plots. The nomenclature of plant species follows Zuloaga et al. Some of the plant community names are tentative. ID is the access number in the database CL-Dataveg. Algunos de los nombres de comunidades vegetales son tentativos.
The subset used for this ofrmas is restricted to vascular plants taxa in total; mosses, lichens and algae are excluded. We added the coordinates of sampling localities, which were either recorded in the field by raunkiqer a GPS device i. This gradient includes sites with annual mean temperatures ranging from 6. In order to produce sociological groups of species species of similar ecological requirementswe classified them into co-occurrence groups inverse classification according to Wilson et al.
Rare species, occurring in less than 7 plots, were excluded from the input matrix. Such species could be recorded by chance or due to introgression from the local neighbouring vegetation and may interfere in the statistical analyses. Hence the vascular plant species included in the original dataset were reduced to species. This test was applied to the same dissimilarity matrix as for classification and running 1, permutations.
In this analysis the index A chance corrected within-group agreement estimates the proportion of the distances explained by group identity and varies from 1 all sample within groups are identical to 0 within-group heterogeneity equals the expectation by chance. Both, hierarchical clustering and MRPP were carried out using the package vegan http: For the manipulation and display of the classification dendrogram we used the package ggdendro http: An additional a priori classification of species was defined according to available syntaxonomic studies.
In such studies, plant species with forrmas fidelity values for a syntaxa class, order, alliance or association are defined as diagnostic. Thus a diagnostic species of a class is frequently occurring in this class and absent in other classes due to matching of ecological requirements of this species and the properties of habitats occupied by the class Bruelheide Diagnostic species for the classes Nanojuncetea australis, Limoselletea australis and Littorelletea australis.
Geographical distribution of analyzed samples.
Floristic, frequency, and vegetation life-form spectra of a cerrado site
This information is displayed in Appendix A. For that purpose, the function assocstats of the R-package vcd version 1.
To describe the climatic gradient following the latitudinal distribution of sites we superimposed an ESRI-shapefile over climatic raster-dataset obtained from the WorldClim database Hijmans et al. In order to reduce the redundancy by highly correlated climatic variables, a principal component analysis PCA was carried out using the R-function prcomp.
Coordinates and climatic information were imported from the ESRI- shapefile to R using the package maptools http: Herewith we eliminated duplicates in the dataset plots sampled in the same locality. Previous to analysis we re-scaled the values of each climatic variable to a distribution with mean value 0 and standard deviation 1 by using the R-function scale. To determine correlations between variables we used the PCA loadings, where high and low values indicate positive respectively negative correlation of a variable with a PCA axis.
To analyse the correspondence between presence of species and PCA dimensions summarizing correlated climatic variables, we exported the PCA scores to the sampling localities into the dataset and draw boxplots showing the dispersal of assemblages in the PCA scores. Diagnostic groups of plant species defined a priori according to Deil et al. According to hierarchical clustering we defined 7 co-occurrence groups and arranged them from north to south according to their median latitudinal distribution.
The classification dendrogram is presented in Fig. The size of the groups ranges from 9 assemblage 6 to 22 species assemblage 7. Most of the dwarf wetland annuals were clustered in assemblage 1, while assemblage 6 is dominated by Nanojuncetea australis and assemblage 7 by Littorelletea australis species.
Therophytes dominate the assemblages 1, 2, 4 and 5, while hemicryptophytes are dominating the assemblages 3, 6 and 7. They are also the majority in every assemblage. The latitudinal distribution of species is in general very variable within co-occurrence groups Fig. Most of the groups occur along the whole gradient. Classification dendrogram of species according to hierarchical clustering.
Symbols of single species show groups defined a priori see legend: Grey frames show the single assemblages with assigned numbers identifiers bellow.
Cross classification table comparing species assemblages obtained by hierarchical clustering versus species groups defined a priori Alife forms B and status of the species in South America C.
Life forms are coded as T therophytes, i. Species status is either native nat.
El origen corresponde a plantaas nativas nat. The sampling localities show a clear geographic and climatic pattern from higher mean temperatures and lower rainfall in the North to cooler and wetter climate in the South.
Mean annual temperature ranges from Climatic stations used as reference show a very similar trend in the latitudinal direction. Although Argentinean plots are located at higher altitudes at same latitudes of Chilean plots, they do not divert too much in the mentioned climatic patterns Fig.
According to the PCA loadings, 4 groups of climatic variables could be defined, highly correlated between each other Table IV. The latitude, also included in this analysis, is mainly correlated with PCA 1, indicating the geographic trend in the ordination from low North to high scores South. Geographic distribution of sampling localities and weather stations versus gradients of altitude, temperature and rainfall at the sampling localities according to the WorldClim database Hijmans et al.
Bottom plot shows the occurrence of species assemblages defined by hierarchical clustering black dotsindicating their respective latitudinal medians grey circles.
Character species of vernal pool habitats are related to the Nanojuncetea australis Deil Therefore this class is well represented in our dataset and is discriminated by the hierarchical clustering plaantas the assemblages 3, 5 and 6 Table III. Most of these clusters are dominated by annuals.