The vegetation of mining dumps in SW‐Sardinia

Abstract

The vegetation of mining dumps of SW-Sardinia includes\ud several endemic or rare species, that have\ud been confined to such artificial habitats by a millennial\ud mining activity. The extreme edaphic specialization\ud of these species reflects with unusual fidelity the\ud heterogeneity of substrata, therefore creating a system\ud of plant communities that largely contributes to\ud the environmental diversity of this part of the island.\ud The phytosociological study presented in this paper\ud recognized eight associations, distinguished by the\ud cluster analysis in two main groups, the first including\ud hemicrypto-chamaephytic vegetation, the second\ud including nanophanerophytic garigues.\ud Six associations are belonging to the first group,\ud five of which newly described: Helichryso tyrrhenici-\ud Dianthetum sardoi ass. nova occurring on\ud gross-grained, hard-sloping dumps deriving from the\ud geologic unit of Gonnesa; Coincyo recurvatae-\ud Helichrysetum tyrrhenici ass. nova colonizing\ud dumps made of metamorphitic flakes and finer particles;\ud Resedo luteolae-Limonietum merxmuelleri\ud ass. nova colonizing small-grained mining dumps\ud with high concentrations in sulphides and heavy\ud metals; Ptilostemono casabonae-Iberidetum integerrimae\ud ass. nova replacing the previous one on\ud older and more consolidated dumps, where the concentration\ud of phytotoxic elements was reduced by\ud the meteoric agents; Epipactidetum tremolsii ass.\ud nova colonizing muddy deposits originating from\ud ferrous clay; Euphorbio cupanii-Santolinetum insularis\ud ANGIOLINI & BACCHETTA 2003, occurring on\ud very old, stabilized dumps. All these associations\ud can be ascribed to the class Scrophulario-Helichrysetea\ud BRULLO, SCELSI & SPAMPINATO 1998. Within\ud this class, a new Sardo-Corsican alliance, Ptilostemono\ud casabonae-Euphorbion cupanii all. nov. is\ud here proposed, differentiated by a pool of rare or\ud endemic species. In addition to the above-mentioned associations, it is proposed, as well, to include into\ud the new alliance the Polygono scoparii-Helichrysetum\ud tyrrhenici BIONDI, VAGGE, FOGU & MOSSA 1996\ud corr., that was described for the gravelly riverbeds of\ud Central-Southern Sardinia.\ud As concerns the second group, two new association\ud have been recognized: Dorycnio suffruticosi-\ud Genistetum corsicae ass. nova, found on abandoned,\ud well consolidated mining dumps, with an upper\ud layer altered by pedogenetic processes; Polygalo\ud sardoae-Linetum muelleri ass. nova, occurring in\ud the vicinities of the mines on steep rocky slopes\ud made of Paleozoic metalliferous limestones. Both of\ud them can be ascribed to the alliance Teucrion mari\ud GAMISANS & MURACCIOLE 1985, grouping the\ud Sardo-Corsican aspects of Cisto-Lavanduletea BR.-\ud BL. in BR.-BL., MOLINIER & WAGNER 1940.\ud Two taxa are new for science: Dianthus sardous\ud BACCHETTA, BRULLO, CASTI & GIUSSO, sp. nova and\ud Helichrysum microphyllum (WILLD.) CAMB. subsp.\ud tyrrhenicum BACCHETTA, BRULLO & GIUSSO, subsp.\ud nova

Septoglomus jasnowskae and Septoglomus turnauae, two new species of arbuscular mycorrhizal fungi (Glomeromycota)

“…In the field the first fungal species was associated with roots of Ammophila arenaria (L.) Link and an unrecognized plant species colonizing dunes of the Mediterranean Sea belonging to Greece and Spain, respectively, and the second fungus formed mycorrhiza with a Cistum sp. (Cistaceae) growing in Italy in soil highly acidified and contaminated with heavy metals (Angioloni et al 2005). Subsequent phylogenetic analyses of sequences spanning the small subunit (SSU, partial) gene, the internal transcribed spacer (ITS1, 5.8S, ITS2, full) and the large subunit (LSU, partial) nrDNA gene, named here SSU-ITS-LSU, and morphological studies of spores and mycorrhizae confirmed our supposition and placed both fungi among Septoglomus spp.…”

“…Spores of S. turnauae were isolated from one pot trap culture inoculated with the rhizosphere soil and root fragments of a Cistus sp. growing in a mine with soil highly acidified and contaminated with heavy metals (Angioloni et al 2005). This mine is located in SulcisIglesiente, SW-Sardinia, Italy (39°28′51″N, 8°28′51″E; altitude 384.20 m).…”

Use of native species and biodegradable chelating agents in the phytoremediation of abandoned mining areas

“…The plant selection was based on previous field studies related to geobotanical aspects of SW-Sardinia mining areas [2,3,4] and was directed to choose metal tolerant plants which develop enough biomass to decontaminate the soil in acceptable times. Three little shrub species that often occur on contaminated substrata were selected.…”

Chemical composition and biological activity of the essential oil from Helichrysum microphyllum Cambess. ssp. tyrrhenicum Bacch., Brullo e Giusso growing in La Maddalena Archipelago, Sardinia.

“…This plant is a shrub, 25-40 cm in height, strongly aromatic, with linear leaves, the lower not longer than 12 mm; the flowers are grouped in yellow heads and fruits are brown achenes 1 . It is used in Sardinian traditional medicine to nurse cough, burns and as antirheumatic and analgesic 2 .…”