European Vegetation Archive (EVA): An integrated database of European vegetation plots

© 2016 International Association for Vegetation Science. The European Vegetation Archive (EVA) is a centralized database of European vegetation plots developed by the IAVS Working Group European Vegetation Survey. It has been in development since 2012 and first made available for use in research projects in 2014. It stores copies of national and regional vegetation- plot databases on a single software platform. Data storage in EVA does not affect on-going independent development of the contributing databases, which remain the property of the data contributors. EVA uses a prototype of the database management software TURBOVEG 3 developed for joint management of multiple databases that use different species lists. This is facilitated by the SynBioSys Taxon Database, a system of taxon names and concepts used in the individual European databases and their corresponding names on a unified list of European flora. TURBOVEG 3 also includes procedures for handling data requests, selections and provisions according to the approved EVA Data Property and Governance Rules. By 30 June 2015, 61 databases from all European regions have joined EVA, contributing in total 1 027 376 vegetation plots, 82% of them with geographic coordinates, from 57 countries. EVA provides a unique data source for large-scale analyses of European vegetation diversity both for fundamental research and nature conservation applications. Updated information on EVA is available online at http://euroveg.org/eva-database

AN ECOLOGICAL CLASSIFICATION OF FLORISTICAL RELEVES BY COUPLING A REGIONAL SURVEY WITH A NATIONAL DATA BANK

The proposed method is based only on tlotistical data and nevertheless classifies the relevés into ecological groupings, corresponding to as similar environments as possible. It begins by calibrating the behaviour of each plant along a large gradient, in a national data bank of floristical releves, on the scale of France, the bank Sophy. It calibrates the behaviour of a plant by its fidelities to the 5,626 other plants of the bank, which are considered as indices of the environment. It defines a statistical space having 5.626 dimensions in which: 1) an axis measures the fidelity to a plant, considered as an ecological index; 2) a dot corresponds to the behaviour of a plant towards the indices; 3) the distance between two dots expresses the ecological difference between two behaviours; 4) the centre of gravity for the plants of a releve indicates the probable position of the relev6; 5) the distance between two releves expresses their ecological difference. Compared with this method, the correspondence factor analysis CFA: 1) locates the releves in a space, according to the fidelities of plants to releves, showing their floristical differences; 2) gives a weight to a plant according to its rarity, not its ecological behaviour; 3) deals only with subsets of the releves and rehandle the subsets by successive approximations; 4) transfers onto the graphs the empirical and intuitive method of a naturalist during field-work, The method is applied to about 400 releves in a district in the Northern Vosges (France). It generates an automatic classification of the releves, at several levels of synthesis. including the upper levels above the phytosociological classes. It explains half of the peculiarity of a type of plant community with 10 to 30 discriminant plants, which are the quantitative and gradual homologues of characteristic species

REPEATABILITY OF THE FRENCH HIGHER VEGETATION TYPES ACCORDING

Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1) The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2) In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3) At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4) Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable

EXCHANGE OF FLORISTICS RELEVES OR EXCHANGE OF CALIBRATIONS BETWEEN DATA BANKS?

In vegetation science, an exchange between two floristical data banks increases the ecological gradient of the registered releves. Therefore, it also increases the discrimination between the behaviours of plants and, because of this, the distinctness of types of plant community. In practice, an exchange is restricted, on one hand by the priority given to the authors for processing their own releves and, on the other hand, by the interest of a bank which needs a benefit from its registered files, in order to support and develop the data processing. On the other hand, there is another kind of exchange, that of the socio-ecological calibrations of plants, which keeps the data in their initial bank and so protects everyone's interest. That exchange unites the gradients of the banks and improves the understanding of the releves. The socioecological calibI-ation of a plant is the set of its fidelities compared to all the plants of the bank. The calibration defines a statistical space of fidelities, where distances express the implicit ecological differences and determine the classification of relevès in types of plant communities corresponding to homogenous environments. The melting of the calibrations coming from two banks defines a common space of fidelities where plants and releves are localized and classified according to the common gradient covered by the two banks together

REPEATABILITY OF THE FRENCH HIGHER VEGETATION TYPES ACCORDING

Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1) The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2) In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3) At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4) Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable