10 th <str<strong>on</strong>g>Symposium</str<strong>on</strong>g> <strong>on</strong> <strong>the</strong> <strong>Flora</strong> <strong>of</strong> Sou<strong>the</strong>astern <strong>Serbia</strong> <strong>and</strong> Neighbouring regi<strong>on</strong>s,Vlasina 17 to 20 June 2010karst fields. The majority <strong>of</strong> species were found <strong>on</strong> open peatl<strong>and</strong>s (Sphagnumpalustre, Sph. capillifolium, Sph. denticulatum, Sph. c<strong>on</strong>tortum, Sph. subsecundum,Sph. cuspidatum, Sph. magellanicum, Sph. angustifolium, Sph. squarrosum, Sph.teres, Sph. compactum, Sph. centrale, Sph. flexuosum, Sph. papillosum <strong>and</strong> Sph.tenellum). In terms <strong>of</strong> plant sociology bog communities bel<strong>on</strong>gs to ass. Drosero –Caricetum stelullatae <strong>and</strong> Rhynchosporetum albae, both communities <strong>of</strong> transitivepeatl<strong>and</strong>s. St<strong>and</strong> s <strong>of</strong> Sphagnum medium – Polytrichum strictum <strong>and</strong> Sphagnumcapillifolium – Polytrichum l<strong>on</strong>gisetum can be recognised as fragments <strong>of</strong> raisedbogs. All peatl<strong>and</strong>s are under str<strong>on</strong>g pressure <strong>of</strong> natural successi<strong>on</strong>. Sph.quinquefarium was found <strong>on</strong> granite <strong>and</strong> silicate rocks within beech woods (ass.Blechno-Fagetum <strong>and</strong> st<strong>and</strong>s <strong>of</strong> Fagus sylvatica – Sphagnum quinquefarium). Thisspecies is also known from st<strong>and</strong>s <strong>of</strong> Pinus mugo. This st<strong>and</strong>s <strong>of</strong> mountain pine aredeveloped in deep karst dolines <strong>and</strong> could be classified as ass. Pino mugo –Sphagnetum. O<strong>the</strong>r peat moss species present here is Sph. girgensohnii. In wetwoods <strong>of</strong> spruce <strong>and</strong>/or fir (ass. Carici brizoidis – Abietetum, Blechno – Abietetum,st<strong>and</strong>s <strong>of</strong> Picea abies – Sphagnum sp. div.) Sph. platyphyllum, Sph. squarrosum,Sph. fimbriatum, Sph. angustifolium, Sph. palustre <strong>and</strong> Sph. girgensohnii developsloose or more or less dense mats. Only <strong>on</strong>e locality in wood <strong>of</strong> sessile oak <strong>and</strong>chestnut is known (ass. Querco – Castanetum sativae) with spesies Sph.angustifolium <strong>and</strong> Sph. fimbriatum distributed around small shallow lake. The mostunusual habitat <strong>of</strong> peat mosses is periodically flooded karst field where <strong>the</strong>y grow indifferent grassl<strong>and</strong> communities (e.g. ass. Nardetum strictae, Crepidi c<strong>on</strong>yzaefoliae– Molinietum altissimae) <strong>and</strong> community <strong>of</strong> blister sedge (ass. Caricetumvesicariae). Peat mosses growing in karst field are Sph. subnitens, Sph.capillidolium, Sph. teres, Sph. palustre <strong>and</strong>. Sph. denticulatum. All describedhabitats have very narrow areas <strong>of</strong> distributi<strong>on</strong>, <strong>and</strong> are under str<strong>on</strong>g pressure <strong>of</strong>successi<strong>on</strong>, change <strong>of</strong> hydrology, deforestati<strong>on</strong>, <strong>and</strong> different negative humanimpacts. Therefore active protecti<strong>on</strong> measures are <strong>of</strong> urgent necessity.26
10 th <str<strong>on</strong>g>Symposium</str<strong>on</strong>g> <strong>on</strong> <strong>the</strong> <strong>Flora</strong> <strong>of</strong> Sou<strong>the</strong>astern <strong>Serbia</strong> <strong>and</strong> Neighbouring regi<strong>on</strong>s,Vlasina 17 to 20 June 201010 th <str<strong>on</strong>g>Symposium</str<strong>on</strong>g> <strong>on</strong> <strong>the</strong> <strong>Flora</strong> <strong>of</strong>Sou<strong>the</strong>astern <strong>Serbia</strong><strong>and</strong> Neighbouring regi<strong>on</strong>s,Vlasina 17 to 20 June 2010Phytogeography, Floristics <strong>and</strong> PhytoecologyFitogeografija, floristika i fitoekologija27