In October 2009, during a sampling campaign for recovery of vegetation germplasm in the Iblei Mts., a new population of Zelkova sicula, a very threatened tree species endemic to Sicily was fortuitously found on the north-eastern slopes of the Iblei Mts.. The new site lies 310 to 350 m a.s.l., some 17 km east from the only known site of Bosco Pisano (Buccheri). Local landscape is a patchy mosaic in which open woodlands and pasturelands alternate to food and forage crops. The most common tree species are Olea europaea var. sylvestris, Quercus virgiliana, Quercus suber, whereas Pyrus spinosa, Sarcopoterium spinosum, Calicotome infesta and Phillyrea latifolia are the most widespread shrubs. As previously observed at Bosco Pisano, also in the new site Z. sicula grows on plio-pleistocenic basalts with a rather good amount of potential water supply. Following Rivas-Martínez bioclimatic classification, the new population falls within the thermo-Mediterranean belt, ombrotype lower subhumid. The new population has a total area of occupancy of about 8,000 m2 and consists of several hundreds of discrete trees, which are mainly widespread within the bottom and the riversides of a small, south-north streaming gully, somewhere embanked and with large outcropping basalt blocks. During our surveys no fruiting tree was observed, while vegetative reproduction through root sprouting is quite common, as already known for the Bosco Pisano population. In respect to it, the overall conditions of the stand appear better in terms of health and vigour, either at trees as well as at population level. From the vegetation viewpoint the new site looked straightaway quite similar to the former one, but after more thorough observations some novel floristic evidences were noticed, then prompting more detailed phytosociological investigations. The ongoing data collection provided additional information to allow a better understanding of the auto- and synecology of Z. sicula. In the conservationist perspective, the new finding may surely contribute to reduce in the future the risk of extinction for this critically endangered species, although not enough to allow at present its reclassification in a different IUCN Category. Future studies on the genetic structure of this new population and a comparison with the known population from Bosco Pisano will be carried out.
Notes on the finding of a new population of Zelkova sicula Di Pasquale, Garfì et Quézel (Ulmaceae)
Garfì G;Carimi F;Pasta S;
2010
Abstract
In October 2009, during a sampling campaign for recovery of vegetation germplasm in the Iblei Mts., a new population of Zelkova sicula, a very threatened tree species endemic to Sicily was fortuitously found on the north-eastern slopes of the Iblei Mts.. The new site lies 310 to 350 m a.s.l., some 17 km east from the only known site of Bosco Pisano (Buccheri). Local landscape is a patchy mosaic in which open woodlands and pasturelands alternate to food and forage crops. The most common tree species are Olea europaea var. sylvestris, Quercus virgiliana, Quercus suber, whereas Pyrus spinosa, Sarcopoterium spinosum, Calicotome infesta and Phillyrea latifolia are the most widespread shrubs. As previously observed at Bosco Pisano, also in the new site Z. sicula grows on plio-pleistocenic basalts with a rather good amount of potential water supply. Following Rivas-Martínez bioclimatic classification, the new population falls within the thermo-Mediterranean belt, ombrotype lower subhumid. The new population has a total area of occupancy of about 8,000 m2 and consists of several hundreds of discrete trees, which are mainly widespread within the bottom and the riversides of a small, south-north streaming gully, somewhere embanked and with large outcropping basalt blocks. During our surveys no fruiting tree was observed, while vegetative reproduction through root sprouting is quite common, as already known for the Bosco Pisano population. In respect to it, the overall conditions of the stand appear better in terms of health and vigour, either at trees as well as at population level. From the vegetation viewpoint the new site looked straightaway quite similar to the former one, but after more thorough observations some novel floristic evidences were noticed, then prompting more detailed phytosociological investigations. The ongoing data collection provided additional information to allow a better understanding of the auto- and synecology of Z. sicula. In the conservationist perspective, the new finding may surely contribute to reduce in the future the risk of extinction for this critically endangered species, although not enough to allow at present its reclassification in a different IUCN Category. Future studies on the genetic structure of this new population and a comparison with the known population from Bosco Pisano will be carried out.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
