Marisia - Maros Megyei Múzeum Évkönyve 32-34. (2014)
Botany
DESCRIPTION AND THREATS TO NATURA 2000 HABITAT 7220* PETRIFYING SPRINGS WITH TUFA FORMATIONS (CRA TONE URION). A REVIEW Marilena ONETE1, Roxana ION1, Florian Paul BODESCU2 1 Institutul de Biologie Bucure$ti al Academiei Romane, Bucure$ti, Romania, marilena.onete@gmail.com 2 SC Multidimension SRL, Bucure§ti, Romania Abstract: The paper presents the description and threats relating to priority habitat 7220* Petrifying springs with tufa formation (Cratoneurion) listed as priority habitat in Annex I of Habitat Directive 92/43/EEC. The habitat is rare in the world and its importance has required studies in those countries where it occurs. A review of the literature highlighted the plant species composition, and threats in different countries. At the European level, many 7220 habitats are affected by human intervention directly or indirectly by changes in their surroundings. Keywords: petrifying springs, species composition, assessment, monitoring, threats Introduction Assessment and monitoring of biodiversity offer a better understanding of the impact of management actions and identify the ways that management affects biodiversity. Monitoring also offers the possibility of determining whether the management actions fulfil their objectives [10, 20]. The identification of habitats must take into consideration the composition of flora and fauna, their ecological adaptations and their means of dispersal. Most habitats have as a component a plant association. Habitat identification is achieved through the initial identification of the phytocoenoses that characterise, which in turn is based on the diagnostic dominant species and indicator species (ecological and/or phyto-coenological) and site characteristics (geographic location, altitude, relief, soil, etc.) [16]. Calcareous tufa in nature is a white or variously coloured deposit of calcium carbonate (limestone). It develops when groundwater receives carbon dioxide from deep volcanic sources forming weak carbonic acid. When this acid contacts rocks or sediments rich in calcium, it chemically dissolves the calcium forming a solution that can be transported. Once the solution reaches the surface, the carbon dioxide comes out of solution and the dissolved calcium is transformed into calcium carbonate or calcareous tufa. For petrifying springs with tufa formation a combination of the conditions is necessary [23]. 1. Geological: deposits rich in calcium carbonate as a calcium source and suitable groundwater regime; 2. Water chemistry: the presence of waters rich in carbon dioxide, forming solutions with calcium; 3. Suitable groundwater characteristics; and M A R I S I A, XXXIII-XXXIV, p. 71-80
