PARENT SESSION
Poster Session 3: Aquatic Ecology
Monday, August 8, 5:00 PM - 6:30 PM, Exhibit Hall 210 D, Level 2, Palais des congrès de Montréal

Humidity as a factor of dofferentiation of community Lemnetum minoris Th. Muller et Gors1960.

Perisic, Snezana^*,, Mijatovic, Miroslava, Djurdjevic, Lola , Karadzic, Branko , Velickovic, Miroslava,

ABSTRACT- Blace Lake is situated in south Serbia, near township Blace, at the altitude of 395m. Its surface states 12 ha. Community Lemnetum minoris habitats are open water surfaces and littoral zone of the lake characterized with total or partial summer water withdrawal. Those habitats are often populated by herbaceous species. In this community 66 species were recorded. The main edificator is Lemna minor L. Characteristic species are: Ceratophyllum submersum L., Lemna minor L. and Schoenoplectus lacustris L. Association Lemnetum minoris is classified into three subassociations: typhetosum prov., lemnetosum prov. and caricetosum prov. Habitats of community typhetosum prov. populates wide-open water surfaces with no water withdrawal annually. Differential species of this subassociation are: Sparganium ramosum Huds., ssp. neglectum Beeby, Sparganium ramosum Huds. ssp. polyedrum Asch. et Gr., Phragmites communis Trin., Veronica baccabunga L., Typha angustifolia L., Lemna trisulca L. Community lemnetosum prov. inhabits the coasts of Blace Lake during the flooding periods. Lemna trisulca L. and Potamogeton gramineus L. are differential species of this community. Subassociations typhetosum and lemnetosum show cartain similarity due to the presence of Lemna trisulca L., as the common species. Due to extremely high level of the underground water, habitats of subassociation caricaetosum prov. are constatly humid. Juncus conglomeratus L., Carex acutiformis Ehrh., Galega officinalis L., Cirsium arvense L. Scop. var. vestitum Vimm. et Grab., Epilobium hirsutum L., Cardamine pratensis L., Lysimachia nummularia L., Lythrum salicaria L., Capsella bursa-pastoris L., Juncus inflexus L., Plantago major L., Cirsium lanceolatum L., Stachys palustris L., Rumex palustris Sm., Mentha aquatica L., Rumex acetosa L., Holcus lanatus L., Polygonum lapatifolium L. are differential species of this subassociation. The main factor of classification of this fragile community (Lemnetum minoris into subassociations is the level of humidity.