VEGETATION ASPECTS OF SOME HABITATS WITH VIPERA URSINII FROM SĂRĂTURILE LEVEE (DANUBE DELTA) OANA ZAMFIRESCU * Introduction

Transcription

1 Analele ştiinţifice ale Universităţii Al. I. Cuza Iaşi Tomul LVII, fasc. 1, s. II a. Biologie vegetală, 2011 VEGETATION ASPECTS OF SOME HABITATS WITH VIPERA URSINII FROM SĂRĂTURILE LEVEE (DANUBE DELTA) OANA ZAMFIRESCU * Abstract: This study aims to present and analyse, from phytosociologic perspective, the phytocoenoses preferred by Vipera ursinii individuals, of the Sărăturile levee (Danube Delta). Our field investigations showed that most of vipers have been observed in the plant communities with relatively tall grasses and high cover and in the ecotonal areas that are appropriate for thermoregulation. The analysis of the relevés allowed the identification of three phytosociological associations: Juncetum maritimi (Rübel 1930) Pignatti 1953, Juncetum littoralis Popescu et Sanda 1976 (Cl. Juncetea maritimi Br.-Bl. 1931) and Agropyretum elongati I. Şerbănescu 1965 (Cl. Festuco-Puccinelietea Soó 1968). Keywords: habitats, sandy soil, meadow viper, plant communities, Juncus sp. Introduction The Danube Delta Biosphere Reserve is representative for its floristic and phytosociological diversity. One of the major causes of this considerable diversity is the south-eastern European geographical position, closed to the Mediterranean postglacial refuges, and the influences of the eastern refuges, stronger than the central-european ones. Another explanation refers to the high diversity of the habitat types: aquatic, paludal and terrestrial. In this zone exists a meadow viper ( Vipera ursinii) population (see [9] for a complete record list), a species that is considered critically endangered [8, 18] and, therefore, strictly protected according to European (Directive 92/43/EEC/1992 [5]) and national legislation (Romanian Government Ordinance no. 57/ [11]). Our observations showed that the vipers prefer the areas with relatively thick and tall vegetation that displays a general cover of 70-90%, and avoid the salty substrata with relatively short and low-cover vegetation [15, 19]. The current study aims to present and analyse, from floristic and phytosociologic perspective, the phytocoenoses preferred by Vipera ursinii individuals. Materials and methods The vegetation study was done according to the principles of Central-European phytosociological school of vegetation survey (Braun -Blanquet Central European School/School Zürich-Montpellier) [1, 3]. The phytosociological classification was carried out consistent with various authors [2, 12, 13, 14]. The Sărăturile levee lies north from Sfântu Gheorghe village and channel and the principal characteristic is represented by the presence of sands with typical vegetation and salty sands cut off by wet areas. The study area has 62 ha; it is located at about 1 km from the Black Sea (44 54 N, E; ca. 0 m a.s.l.) and has a semi-arid climate (mean annual temperatures and * Alexandru Ioan Cuza University, Faculty of Biology, Bd. Carol I, no. 11, Iasi Romania, o_zamfirescu@yahoo.com 65

2 precipitations of 11.4 C and mm, respectively) [7]. The area (fig. 1) is located in the south-eastern tip of the Sărăturile natural levee, which is an economical zone of the Danube Delta Biosphere Reserve. It is also included in the Natura 2000 network of protected areas as ROSCI0065 Delta Dunării (The Danube Delta) established through the Order of the Minister of Environment and Durable Development 776/ [10]. Sfântu Gheorghe Figure 1. Location of the study area (black contour). 66

3 Results and discussions The analysis of the relevés from the plant communities where the meadow vipers have been observed revealed the presence of the following associations: Juncetum littoralis Popescu et Sanda 1976, Juncetum maritimi (Rübel 1930) Pignatti 1953, and Agropyretum elongati I. Şerbănescu Cl. Juncetea maritimi Br.-Bl Ord. Juncetalia maritimi Br.-Bl Al. Juncion maritimi Br.-Bl Association Juncetum maritimi (Rübel 1930) Pignatti 1953 On the Sărături levee, the plant communities with Juncus maritimus generally appear in low areas with relatively higher humidity, on salty sandy soils, with a superficial thick layer of sand. In the study zone these plant communities cover large areas. They have been recorded and described before from the Black Sea shore, the Danube Delta and from the Chituc and Lupilor levees [16, 17]. The characteristic species is Juncus maritimus, which is at the same time the edifying species. It grows well achieving covers of over 80% in some habitats. The characteristic species of the class Festuco-Puccinelietea are also well represented, which indicates a certain degree of substratum salinity. Species like Suaeda maritima and Salicornia europaea, cited from saltier substrata, were not observed in our study. The presence of the species of the class Phragmiti-Magnocaricetea indicates the substratum relatively high humidity (tab. I). 2. Association Juncetum littoralis Popescu et Sanda 1976 (syn. Juncetum acuti Popescu et Sanda 1976, Artemisio santonici-juncetum littoralis (Popescu et Sanda 1976) Géhu et al. 1994). The plant communities with Juncus littoralis appear on sandy and salty terrains, a little drier than the ones occupied by Juncus maritimus phytocoenoses. The characteristic species are Juncus littoralis and Artemisia santonica. Juncus littoralis is also dominant and often co-occurs with Juncus maritimus. Frequently, this species is accompanied by halophilous or facultatively halophilous species (tab. I). This association comprises two sub-associations: juncetosum littoralis Chifu et al 2010 and juncetosum maritimi Popescu et Sanda We consider that the analysed communities appertain to the sub-association juncetosum littoralis, for its floristic composition is more homogenous and for the clear dominance of the characteristic species. 67

4 Table I. Association Juncetum maritimi (Rübel 1930) Pignatti 1953 (relevés 1-5) and Association Juncetum littoralis Popescu et Sanda 1976 (relevés 6-10) Relevé no Area (m 2 ) Cover (%) Altitude (m.s.m.) Characteristic for associations Juncus maritimus Juncus littoralis Juncion maritimi Artemisia santonica ssp. santonica Aster tripolium ssp. pannonicus Plantago maritima Juncetalia maritimi Lotus tenuis Elymus elongatus Juncetea maritimi Cirsium alatum Puccinelia gigantea Limonium gmelinii Festuco-Puccinellietea Agrostis gigantea ssp. maeotica Bolboschoenus maritimus Carex distans Carex divisa Cynodon dactylon Juncus gerardi Lythrum virgatum Puccinellia distans Puccinellia limosa Schoenoplectus tabernaemontani Bidentetea Bidens tripartita Rumex maritimus Molinio-Arrhenatheretea s.l. Agrostis stolonifera ssp. stolonifera Althaea officinalis Daucus carota ssp. carota Potentilla reptans Taraxacum officinale Festuco-Brometea s.l. Cynanchum acutum Peucedanum arenarium Galio-Urticetea s.l. Elaeagnus angustifolia Variae syntaxa Plantago major Tamarix ramosissima

5 Cl. Festuco-Puccinellietea Soó 1968 Ord. Puccinellietalia Soó 1947 em Vicherek 1973 Al. Puccinellion limosae Klika in Vlach Association Agropyretum elongati Şerbănescu 1965 (syn. Elymetum elongati I. Şerbănescu 1965). The phytocoenoses of this association are widely spread in the Danube Delta, where they appear on sands and salty sandy soils, on the edge of wet microdepressions on soils with superficial sand layer. The characteristic species is Elymus elongatus, which is also the edifying species. It forms thick tussocks with a percentage ground cover of % (tab. II ). Among the tussocks grow a series of halophilous plants: Limonium gmelinii, Puccinellia distans, Carex distans, Juncus gerardii, Taraxacum bessarabicum, Artemisia santonica ssp. santonica etc. Table II. Association Agropyretum elongati I. Şerbănescu 1968 Relevé no Area (m 2 ) Cover (%) Altitude (m.s.m.) Characteristic for association Elymus elongatus Puccinellion limosae Artemisia santonica ssp. santonica Taraxacum bessarabicum Festuca arundinacea ssp. orientalis Festucion pseudovinae Achillea collina Arenaria serpyllifolia Cynodon dactylon Festuca pseudovina Puccinellietalia Polygonum aviculare Scorzonera cana Cypero-Spergularion et Crypsidetalia aculeatae Crypsis aculeata Spergularia media Lactuca saligna Scorzonero-Juncetalia gerardii Bolboschoenus maritimus Carex distans Carex divisa Inula britannica Juncus gerardii Peucedanum latifolium Festuco-Puccinellietea Aster tripolium ssp. tripolium Atriplex littoralis Atriplex prostrata Limonium bellidifolium Limonium gmelinii Lotus corniculatus Lotus tenuis

6 Relevé no Plantago maritima Plantago lanceolata Festuco-Brometea Artemisia austriaca Cynanchum acutum Festuca valesiaca Medicago falcata Medicago minima Linum perenne Poa bulbosa Verbascum chaixii Molinio-Arrhenetheretea Bromus commutatus Elymus repens Lolium perenne Taraxacum officinale Plantaginetea majoris s.l. Cichorium intybus Plantago major Phragmiti-Magnocaricetea s.l. Calamagrostis pseudophragmites Bidentetea s.l. Rumex maritimus Elymetalia gigantei Centaurea arenaria Juncetea maritimi s.l. Juncus littoralis Juncus maritimus Artemisieta s.l. Melilotus albus Variae syntaxa Asparagus pseudoscaber Tamarix ramosissima The plant communities with Juncus maritimus and Juncus littoralis have conservation value because they are included in the Habitats Directive 92/43/EEC as 1410 Mediterranean salt meadows (Juncetalia maritimi) Romanian correspondent is R1501 west-pontic communities with Juncus maritimus and Juncus littoralis [4, 6]. Acknowledgements This work was supported by CNCSIS-UEFISCSU, project PNII-IDEI 2098, no. 1041/2009. REFERENCES 1. BRAUN-BLANQUET J., 1964 Pflanzensoziologie. Grundzűge der Vegetations-kunde. Ed. 3. Springer- Verlag, Wien New York. 2. COLDEA G. (ed.), SANDA V., POPESCU A., ŞTEFAN, N., 1997 Les association végétales de Roumanie. 1. Les associations herbacées naturelles. Presses Universitaires de Cluj, Cluj-Napoca. 3. CRISTEA V., GAFTA D., PEDROTTI F., 2004 Fitosociologie. Edit. Presa Universitară Clujeană, Cluj- Napoca. 4. DONIŢĂ N., POPESCU A., PAUCĂ-COMĂNESCU M., MIHĂILESCU S., BIRIŞ I.-A., 2005 Habitatele din România. Edit. Tehnică Silvică, Bucureşti. 70

7 5. EUROPEAN COMMISSION, 1992 Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora (online). Official Journal L 206, 22/07/1992 P Consolidated version Available at: environment/ nature/ legislation/habitatsdirective /index_en.htm. 6. GAFTA D., MOUNTFORD O. (coord.), 2008 Manual de interpretare a habitatelor Natura 2000 din România. Edit. Risoprint, Cluj-Napoca. 7. GÎŞTESCU P., ŞTIUCĂ R. (eds.), 2006 Delta Dunării Rezervaţie a Biosferei. Edit. Dobrogea, Constanța. 8. IFTIME A., 2005 Reptilia (Reptile). In: Botnariuc N., Tatole V. (eds.), Cartea Roșie a Vertebratelor din România. Edit. Curtea Veche, București, KRECSAK L., ZAMFIRESCU Ş. R., 2008 Vipera ( Acridophaga) ursinii in Romania: historical and present distribution. North-West. J. Zool., 4: MINISTER OF ENVIRONMENT AND DURABLE DEVELOPMENT, 2007 Ordin nr. 776 al Ministerului Mediului si Dezvoltării Durabile privind declararea siturilor de importanţă comunitară, ca parte integrantă a reţelei ecologice europene Natura 2000 în România. Monitorul Oficial al României, ROMANIAN GOVERNMENT, 2007 Ordonanţa de Urgenţă nr. 57 din 20/06/2007 privind regimul ariilor naturale protejate, conservarea habitatelor naturale, a florei şi faunei sălbatice. Monitorul Oficial nr. 442 din 29/06/ SANDA V., ARCUŞ M., 1999 Sintaxonomia grupărilor vegetale din Dobrogea şi Delta Dunării. Edit. Cultura, Piteşti. 13. SANDA V., POPESCU A., BARABAŞ N., 1997 Cenotaxonomia și caracterizarea grupărilor vegetale din România. Stud. Comunic. Muz. Ști. Nat. Bacău, 14: SANDA V., POPESCU A., DOLTU M.I., 1980 Cenotaxonomia şi corologia grupărilor vegetale din România. Stud. Com., Muz. Brukenthal Sibiu, 24: STRUGARIU A., ZAMFIRESCU Ş. R., GHERGHEL I., SĂHLEAN T. C., MORARU V., ZAMFIRESCU O., 2011 A preliminary study on population characteristics and ecology of the critically endangered meadow viper Vipera ursinii in the Romanian Danube Delta. Biologia, 66, 1: ŞTEFAN N, SÂRBU I, OPREA A., ZAMFIRESCU O., 2000 Flora și vegetația Rezervației naturale Grindul Lupilor (Rezervația Biosferei Delta Dunării). Bul. Grăd. Bot. Iaşi, 9: ŞTEFAN N, SÂRBU I, OPREA A., ZAMFIRESCU O., 2001 Contribuții la cunoașterea vegetaţiei Grindurilor Chituc şi Saele-Istria. Bul. Grăd. Bot. Iaşi, 10: TATOLE V., IFTIME A., STAN M., IORGU E.-I., IORGU I., OŢEL V., 2009 Speciile de animale Natura 2000 din România. Lucrare apărută în cadrul programului "Fundamentarea ştiinţifică a unui model de implementare a legislaţiei Natura 2000 în România, luând ca studiu de caz speciile de animale listate în directiva Habitate 92/43/EEC". 19. ZAMFIRESCU Ş. R., STRUGARIU A., GHERGHEL I., ZAMFIRESCU O., 2010 Sfântu Gheorghe (Tulcea, Romania): an important herpetological area. An. Şt. Univ. Al. I. Cuza Iaşi, s. Biol. Anim., 56: