Volume 14(3), 95-98, 2010 JOURNAL of Horticulture, Forestry and Biotechnology The influence on flora and vegetation of the water quality in Liebling accumulation lake Neacşu Alina 1* , Arsene G.G. 1 , Arsene Alina 2 , Stroia C. 1 , Faur F. 1 , Tabuc Cristina 3 1 Banat's University of Agricultural Sciences and Veterinary Medicine, Faculty of Agriculture, Department of Biology, Timişoara, Romania; 2 Monsanto Romania; 3 The National Research – Development for Biology and Animal Nutrition Institute, Bucharest, Romania *Corresponding author. Email: alne76@yahoo.com Abstract Located in Timis County, the Liebling accumulation is one at the most important accumulation lake of the area. At present it is administred by the Association of Sport Fishermen Timisoara. Our research (2005-2009) followed water sampling, analysis and interpretation of the results and the study of the flora and vegetation, making several observations regarding the influence of the water quality on the latter. The chemical analysis of the water samples was performed in keeping with the quality standards included in norm 161/2006 issued by the Ministry of Environment and Water Usage, in the laboratory of the National Administration „Romanian Waters” Banat – Timisoara and consisted in determining the oxygen level, the nutrients, the pH, the suspensions and the water total hardness. The study of the flora implied creating the list of species and their analysis phytogeographically, biologically and ecologically. The study of the vegetation implied the establishment and the description of plant associations (according to the methodology of the Central-European phytocoenologic school). Water analysis indicate the moderate quality, with negative impact on the plant diversity: only 47 % of species are aquatic and paludicolous; concerning vegetation, we observed an excessive development of plant associations that lead to the clogging water. Key words Liebling, chemical parameters, water quality, flora, vegetation Located in Timis county, near Timisoara, the Liebling accumulation lake is situated on the stream Lanca Birda, at 94 m altitude, an area of 60 ha. Now it is administered by the Association of Sport Fishermen in Timisoara (A.P.S.) mainly for fishing and entertainment. Land Code, cadastre as Atlas of water in Romania. Part I – Morpho-hydrographic data on the surface of the river system, issued by Ministry of Environment (1992), is for the lake Liebling V 2.36. The landscape beauty and its distinct flora and vegetation determined us to study more deeply this reservoir. Material and Method Our studies considered water analysis and the study of flora and vegetation. For water sampling there were taken into account the recommendations comprised in series SR ISO 5667/2002 (see norm no. 161/2006 issued by the Ministry of Environment and Water Administration). The chemical analysis of the water samples collected was performed according to the quality standards included in norm no. 161/2006. This analysis took place in the laboratory of the National Administration „Romanian Waters” Banat Waters Division – Timisoara and consisted in determining the oxygen level, the nutrients, the pH, suspensions and total hardness of the water. The study of the flora implied creating the flora summary and its analysis phytogeographically, biologically and ecologically. We have used for determining Flora R.S.R. (1952 – 1976) and Flora ilustrată a României. Pterydophyta et Spermatophyta (CIOCÂRLAN, 2009). For the notation and analysis of indexes we used the study „Caracterizarea ecologică şi fitocenologică a speciilor spontane din flora României” (SANDA et al., 1983). The study of the vegetation is based on the principles of the Central-European phytocoenologic school, which is considering the plants association as fundamental unit in the study of the vegetation. We have thus performed phytocoenologic sampling and after the data processing, examining the specialized references, we established the vegetal associations. We had in view the accomplishment of the summary of cenoetaxonomic units and the analysis of the vegetal associations from various points of view. The study we 95