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The project of the online atlas of Walloon Flora

Marguerites-Libin

The project of the online atlas of Walloon Flora

Collecting data on the flora at different periods of time for realizing species distribution maps and an atlas of the flora is a very useful and essential tool in plant diversity conservation:

  • It gives a precise picture of the species distribution range, current but also past distribution, and of its rarity and can be used to conservation status (UICN criteria).
  • Visualising the distribution of plant species, in particular the rare and threatened ones or the Natura 2000 habitat specialists, allows to localise the areas of interests for conservation (hot-spots of biodiversity, nature core areas), but also to localise areas where populations of rare and threatened taxa are not yet protected (and so to identify sites for designing new natural reserves.
  • The temporal evolution (regression, progression) of the flora (rare taxa but also neophytes and invasive taxa) can be investigated, by comparing different periods of time, in relation to different factors (eutrophication, land use planning, urbanisation, habitat fragmentation, but also ecological management).
  • It can also provide data for environmental monitoring (bio-indicators), impact studies, evaluation of conservation conditions of Natura 2000 habitats, ...

Mapping using the IFBL grid

The mapping is based on the IFBL grid ( carroyage IFBL ), divided in units or squares with a particular coding (Fig. 1), and already used for the former version of the Atlas ("Atlas de la flore belge et luxembourgeoise - Ptéridophytes et Spermatophytes"), published in 1972, and corrected in 1979). The inventory unit for Wallonia is 1x1km. To be able to compare historical and recent data, it is very important to use the same reference grid through time.

Usually it is not possible to inventory all the squares, so an inventory strategy has to be developed so that the number of squares inventoried within a tetrad (unit used in the maps) is representative of the whole and contains the majority of the species present. In Belgium, doing inventories in 9 to 10 of the 16 1x1km squares present in a tetrad (map unit) gives an accurate estimation of the flora present in the tetrad (Van Landuyt et al. 2006).

The inventory has also to be done where data are missing. An inventory state has to be developed, and regularly updated (see l'état de l'échantillonnage ).

Floristic list: description and use

This PPT floristic list (recording sheet (PPT-4314 ko) PDF ) (PDF-198 ko) , is especially adapted for the Atlas of Wallonia. It consists of four A4 sheets, organised so that it avoids many page handlings, and gives information on the recorded taxa.

Attention : to remain friendly, the list is not exhaustive! Most casual, subspontaneous, cultivated and hybrid taxa, a number of infraspecific taxa, and taxa considered as extinct for more than 50 years are missing.

All observed taxa (indigeneous, neophytes, casuals) growing spontaneously (not when planted) have to be recorded within the investigated area. A compromise has to be found between the intensity of the inventory (as complete as possible) and the time spent for inventorying one square.

When there are uncertainties, a validation of the taxon by another botanist or a specialist can be necessary. In this case pictures and/or herbarium material (except when potentially protected) can be useful to collect.

Page 1 : identification form

On the left :

· Two frames, allowing to hachure the investigated zone in the 1x1 km square (scale 1/20.000 or 1/25.000) (NB : this can also be done on a copy of the topographical map, which can be printed via the website ( l'état de l'échantillonnage ) or can be provided on request at the DEMNA ).

· Personal number of the inventory.

· Date or observation period (DD-MM-YY). When a site has been visited several times within a short time period, only one list may be completed, indicating the first and last date of visit.

· Author (recorder's name), i.e. the person owing author's rights on the data.

· The name of the determinator(s).

· Information on the geographic localisation: IFBL 1x1 km square, IGN map number (1/20000 or 1/25000), administrative locality (commune, place, parish, county, canton.).

· An insert for giving precisions on ecology (complements to the right column, topography, soil and bedrock).

· An insert for writing notes (e.g. when peculiarities: casual….) or for giving supplementary taxa not listed on pages 2 and 3.

· Access code of the data: to guarantee author (recorder)'s rights

3 : the detailed data are freely available and disseminated

4: the detailed data are available and disseminated under conditions

5 : the summary data are freely available (grid 1x1, year)

· Recording time: time passed in min. for the inventory, to evaluate the intensity of the inventory effort.

On the right :

· The biotopes (habitats) where the floristic inventory is made. The codes associated with the box to tick (C3.21, G1.87b) correspond to units of the WALEUNIS typology . In some cases, supplementary information is asked and it is therefore necessary to tick a sublevel (a to c, E2.1 to E2.3). When there are contrasted habitats (e.g. forest meadow) in the explored square, it can be useful to do separate floristic lists per habitat.

· An insert to indicate if the data were already sent to one of the project partners, to avoid double records.

Page 2 and page 3 : list of the taxa

The list comprises 1717 taxa , organised into 20 columns. The first seven columns on page 2 consist of 599 species considered as very common (CC), common (C), and rather common (AC) for Wallonia. The last three columns on page 2 and page 3 comprise 1118 taxa considered as rather rare (AR), rare (R), very rare (RR) or exceptional.

Taxa' name is often given in abbreviated form . You can consult a correspondence list between the abbreviations on the floristic list and the complete names on the website ( PDF liste de correspondance (PDF-198 ko) ). The species are classified per alphabetic order according the nomenclature of Lambinon et al. (2004).

Each taxon is preceded by a symbol, to tick. The Latin name of the taxon is printed using particular lay-out (see Table 1), giving the taxonomical level or distribution type. The taxon can be framed or highlighted in grey, giving indication of taxon status (legally protected, rare or threatened species).