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We drew up a checklist of the Italian vegetation (http://www.prodromo-vegetazione-italia.org/), up to the syntaxonomical rank of alliance. During the compilation of this checklist, we observed that some syntaxa were invalidly published. For this reason, in this article we validated some syntaxa names and, at the same time, described new syntaxa of different hierarchical levels. Therefore, 10 new orders, 1 new suborder, 18 new alliances, 3 new suballiances and 5 new associations are described here. These new syntaxa belong to the following classes:Adiantetea capilli-veneris,Parietarietea judaicae,Thlaspietea rotundifolii,Artemisietea vulgaris,Stellarietea mediae,Galio aparines–Urticetea dioicae,Mulgedio alpini–Aconitetea variegati,Trifolio medii–Geranietea sanguinei,Festuco-Seslerietea,Salicetea herbaceae,Festuco valesiacae–Brometea erecti,Molinio-Arrhenatheretea,Cisto cretici–Micromerietea julianae,Rhamno catharticae–Prunetea spinosae,Salici purpureae–Populetea nigrae,Salicetea purpureae,Quercetea ilicisandQuerco roboris–Fagetea sylvaticae. [ABSTRACT FROM AUTHOR]

The specific species-rich high-altitude vegetation of the classCarici rupestris-Kobresietea bellardiiOhba 1974 (CK), with the occurrence of many arctic-alpine and endemic species, was chosen for a case study. The analyses were based on a dataset of 37,204 phytosociological relevés from the Slovak Vegetation Database. The traditional classification of the class CK, based on cluster analyses, was reproduced satisfactorily by means of formalised classification, based on the formal definitions created by the Cocktail method together with the frequency-positive fidelity index affiliation. Unequivocal assignment criteria for all eight associations of both alliances [Oxytropido-ElynionBr.-Bl. (1948) 1949 andFestucion versicolorisKrajina 1933] of the class CK were formulated. The formal delimitations followed the traditional ones very well. It was demonstrated that the results of applying the formal definitions created on the basis of a large, geographically stratified dataset capturing the occurrence of all vegetation types in Slovakia were highly similar in comparison with the traditional classification based on the results of cluster analysis. The reliability and the pros and cons of the expert system are also discussed. [ABSTRACT FROM AUTHOR]

In this study, we validated some syntaxa, the published names of which were regarded as invalid on the basis of the International Code of Phytosociological Nomenclature. The validations concern syntaxa of different hierarchical levels, belonging to different phytosociological classes. Most validations regard syntaxa that are invalid with respect to art. 5 of the Code. Indeed, the nomenclatural types were not indicated in the correct form (typus, holotypus, lectotypus, and neotypus). [ABSTRACT FROM AUTHOR]

Though the multi-classifier system (MCS) has been used widely in the area of machine learning, it has rarely been used in processing remotely sensed data. To test whether MCS could improve land cover classification results from remote sensing imagery, conservative voting, majority voting, and plurality voting were processed to combine individual classification results in this study. Considering the characteristics of high spatial resolution imagery, object-oriented classification methods were employed. Firstly, the objects were acquired by segmenting the original images at two scales; then taking the "objects" as the classification units, five kinds of classifiers iterative self-organising data analysis (ISODATA), Mahalanobis distance, maximum likelihood, neural network, and expert system were selected to classify urban vegetation categories using different samples and feature spaces to maintain independence among individual classifiers. The three voting rules were then used to combine the individual classification results. For unclassified objects, the ISODATA method was used again to identify their categories. The accuracy assessment showed that the three combined classification results gained higher accuracy than the individual classifier, and the plurality voting rules obtained the best identification results. [ABSTRACT FROM AUTHOR]

The original material of Hypnum ochraceum Turner ex Wilson consists of 13 collections (one fragmentary) kept at the BM and one at the herbarium of Smith (LINN). A specimen in the BM is designated here as lectotype. [ABSTRACT FROM AUTHOR]

The encouraging results obtained in a previous work induced the authors to pursue here the characterization of the structure of the vegetation in northern Portugal, using the phytostructural methodology proposed earlier by the authors. With this objective, eight different types of vegetal communities, representative of the apparent states of the successional process present in this area, and representing the diversity of plant community types in the same area, were selected. The phytostructural method was elaborated on the basis of three types of structural basic matrices regarding diversity, abundance and cover. The data obtained were collected in a contingency matrix, which was then treated by means of a statistical multivariate analysis. Three structural tendencies emerged from this analysis. With the aim of studying their stability, the results are discussed in terms of resistance and resilience, according to the Highest Expressive Amplitude (HEA) concept, and by considering the intra- and inter-community structural dynamics as structural parameters. The data obtained suggest structural situations with different degrees of non-equilibrium that reflect resistance to environmental factors. The resistance of the vegetation is correlated with the apparent functional connectivity detected for the communities analysed. [ABSTRACT FROM AUTHOR]

A syntaxonomic and phytogeographic delimitation of the calcareous open sedge swards in the alpine belt of the Alps ( Caricion firmae ) and subalpine and alpine tussock grasslands in wind-exposed habitats ( Seslerion juncifoliae ) in the area of the south-eastern Alps and of the Dinaric mountains was performed. Analyses based on hierarchical classification, ordination and chorology clearly showed the distinction between the syntaxa: stands from the Liburnian karst (Mt Snežnik – SW. Slovenia, Mts Risnjak and Snježnik – NW. Croatia), Lička Plješivica and the Velebit mountains belong to the Dinaric alliance Seslerion juncifoliae , whereas stands from the Trnovski gozd plateau (W. Slovenia, north-westernmost part of the Dinaric mountains), although somewhat transitional between the two alliances, and stands from the Alps, were classified in the alliance Caricion firmae . The alliance Seslerion juncifoliae of the Dinaric mountains vicariates Caricion firmae of the Alps. [ABSTRACT FROM AUTHOR]

The objective of this study is to find a better method for sub-pixel classification of vegetation. The proposed new technique of a linear mixing model (LMM) is the sequential combination of spectral LMM and temporal LMM. Sub-pixel components of 'relative green vegetation' are derived by spectral LMM; sub-pixel components of vegetation types are estimated by subsequent temporal LMM. The proposed method was applied to five temporal Landsat Enhanced Thematic Mapper (ETM) images for the year 2000 for areas south of Lake Baikal, Russia. Dominant vegetation types there are pine, birch/aspen, shrubs and wheat with weedy plants. Ground truth data of vegetation types were prepared by field survey and visual interpretation of Landsat ETM images by experts. Both the comparisons of classification results among the proposed method and conventional LMM methods and the simulation results among them indicate that the proposed spectral and temporal LMM has better accuracy than conventional methods. [ABSTRACT FROM AUTHOR]

Multiple linear regression techniques have been used to assess rangeland Net Primary Production (NPP) in Senegal. The biophysical principles of assessing NPP as a function of the Absorbed Photosynthetic Active Radiation (APAR) accumulated during the growing season, multiplied by the efficient coefficient (ε), have been used for the work. Accumulated APAR can be substituted with the seasonal integration of NDVI multiplied by the Photosynthetic Active Radiation (PAR). However, a linear regression showed that the NDVI alone was a better and more consistent estimator of rangeland NPP compared with the use of NDVI combined with the PAR data. A first characterization of environmental and climatic variability was attempted. Soil and vegetation information was used and GIS interpolation tools were exploited to create spatial surfaces of environmental and climatic variables from point observations. A multiple linear regression with the independent variables: integrated NDVI, percentage tree cover and mean surface temperature, improved significantly the level of explained NPP (from 71 to 82 per cent). This model was valid for two years of data. [ABSTRACT FROM AUTHOR]

Examines the status of conifers in vegetation classifications in the U.S. Traits of conifers; Ecology of conifer species; Degree of the conifer ecological dominance.

Focuses on a physiognomic classificationa of vegetation. Distribution of organinisms on earth; Use of maps as basic tools; Natural classification of vegetation.