SAG - Saginetea maritimae Westhoff et al. 1962

Classification phytosociologique européenne (Eurovegchecklist, 2016)

Diagnose

Atlantic-Mediterranean and Macaronesian ephemeral winter-annual vegetation in disturbed saline habitats and inland saline badlands

Remarques

sag01 : The communities of this class typically occupy small disturbed sites within large stands of the Juncetea maritimi Br.-Bl. in Br.-Bl. et al. 1952, often characterised by some sand deposition. These transitional habitats connect the Juncetea maritimi and the Koelerio-Corynephoretea and support specific taxa that prompted some authors to establish a separate class for this ecotone. However, some other authors have highlighted that in the Saginetea maritimae the character species of the Juncetea maritimi prevail and thus, the Saginetea maritimae should be included in the latter class. For example, Dierßen & Dierßen (1996) suggested subordinating all Nordic syntaxa of the Saginetea maritimae into the Armerion maritimae (Juncetea maritimi). Also, Polte (2001, 2004) found that the Saginetalia maritimae shows such little floristic distinction towards other salt marsh communities that that they do not deserve a status of class in their own right, but rather should be included into the Juncetea maritimi (best placed there as an alliance within the Juncetalia maritimi). An ad hoc implementation of this alternative view would suggest placing the orders Saginetalia maritimae and Frankenietalia pulverulentae in the Juncetea maritimi. (JD) KD also suggests that because the character species of the class show regionally different frequency, the distinction of this class from the Juncetea maritimi is weak. The opinions expressed above focus on floristic co-occurrence that might be a result of sampling scale; they also neglect the unique ecological nature of the Saginetea maritimae. The communities of this class occur in ecotonal situations spanning two different contrasting macrohabitats of the coastal dunes and coastal salt marshes, linked by steep dry-wet and fresh-saline gradients. The communities of the Isoëto-Nanojuncetea can be seen as a 'freshwater' analogue. The dynamic ecology (ecological filters or selective pressures) of these transitional habitats selects for a unique set of flora characterised by increased occurrence of short-lived herbs. It is not surprising that the relevés of the Saginetea maritimae communities have high number of the Juncetea maritimi species. Firstly, the stands of both communities are (as a rule) sampled using different plot sizes (large for the Juncetea maritimi, small for the Saginetea maritimae), hence the Saginetea maritimae species are often 'captured' as belonging to the Juncetea maritimi; and secondly, because of their spatial juxtaposition, admixture of phytocoenologic elements in both directions is a frequent phenomenon. (LM, JS).

Bibliographie

 Mucina L., Bültmann H., Dierßen K., Theurillat J.-P., Raus Th., Čarni A., Šumberová K., Willner W., Dengler J., Gavilán García R., Chytrý M., Hájek M., Di Pietro R., Iakushenko D., Pallas J., Daniëls F.J.A., Bergmeier E., Santos Guerra A., Ermakov N., Valachovič M., Schaminée J.H.J., Lysenko T., Didukh Y.P., Pignatti S., Rodwell J.S., Capelo J., Weber H.E., Solomeshch A., Dimopoulos P., Aguiar C., Hennekens S.M. & Tichý L., 2016. Vegetation of Europe: hierarchical floristic classification system of vascular plant, bryophyte, lichen, and algal communities. Applied Vegetation Science, 19 (Suppl. 1) : 3-264. (Source)