INVESTIGATIONS OVER THE PHYTOCOENOTIC ROLE OF ASTER SEDIFOLIUS L. IN THE EASTERN PART OF ROMANIA (MOLDAVIA)

Transcription

1 NVESTATONS OVER TE PYTOCOENOTC ROLE OF ASTER SEDFOLUS L. N TE EASTERN PART OF ROMANA (MOLDAVA) Aster sedifolius L. is a vascular plant, sporadically met in Romania, from forest-steppe to hills region, settled in meadows, bushes, in everglades of the forests, on slopes, on eumesobasic soils, moist (often wet in springs), poor in humus, moderately salinized. We analyzed here the role of this species in edification of some meso-halophilous communities, unknown till now in the eastern part of Romania (Moldavia). On the basis of the field relevkes, arranged in an analytic table, we made coenotaonomic, phytogeographic, as well as ecologic analyses of those plant communities, framed by us in the net coenotaa: C1. Puccinellio-Salicomietea Topa 199, Ord. Puccinellietalia So 19 em. Vicherek 19, Al. Festucion pseudovinae Sob 19, Ass. Achilleo-Festucetum pseudovinae (Magyar 192) So (19) 19, subass. asteretosum sedijolii subass. nova. Key words: halophilous vegetation, salt meadows, Puccinellio-Salicornietea, Aster sedifolius, new subassociation. Aster sedifolius L. is a Continental-Eurasian plant, mesohalophylous to mesohygro-halophylous, being sporadically met in Romania, distributed on meadows, bushes, in everglades of the forests, in places more or less wet and salty, from the steppe zone to the nemoral belt [Topa, 199; Bucur et al., 190; Morariu et Nyhrady, 19; Popescu et Sanda, 199; Ciocklan, 2000; Oprea, From the phytoceonotic point of view, this plant is characteristic for the Ord. Puccinellietalia So 19 em. Vicherek 19 [Popescu et Sanda, 199; Chifu et al., t has been identified in the floristic structure of the net halophylous associations, in Romania [Topa, 199; SerbSmescu, 19; Pop, 2000; Chifu et al., 2001: eleochloetum shoenoides (So 19) Topa 199 em. Pop 19 (1'); Astero pannonici-puccinellietum distantis Chu, Roman et Boullet 199 (rf); Puccinellietum limosae Rapaics e So 19 (1; Nitrario-Artemisietum maritimae ' University of Agricultural Sciences and Veterinary Medicine "1.1. de la Brad",, M. Sadoveanu Str., agi, Romania, culita9@yahoo.com; ' "A. Ftu1' Botanical ardens, -9, Dumbrava Ro~ie Str., agi, Romania, aoprea@uaic.ro ROM. J. B0L.-PLANT BOL., VOLUME, No 1, P. 9-0, Bucharest, 2009

2 0 C. Sirbu, A. Oprea 2 Mititelu et al. 199, 190 (1'); Leuzeetum salinae (Borza 19 1 n. n.) RZiv&rut 19 (1; Agrostio-Beckmanietum (Rapaics 191) So 19 (1'); Limonio gmelini- Artemisietum monogvnae Topa 199 (+-'); Artemisio-Festucetum pseudovinae (); Peucedano-Asteretum sedifolii So 19 corr. Borhidi 199 (Syn.: Peucedano- Festucetum pseudovinae (Rapaics 192) Pop 19) (111"' - Vt"). Also, Aster sedifolius, is sometimes present only as a companion species (r"- f) in the structure of some vegetal communities, without a halophylous feature, as they are: Fraino pallisae-quercetum pedunculzjlorae (Popescu et al. 199) Ad. Oprea 199; Fraino pannonici-ulmetum So in Aszod 19 corr. So 19 evonymetosum nanae Chifu et al. 200; Potentilletum anserinae Felfdldy 192 etc. [Oprea, 199; Chifu et al., The communities (co-) dominated by the species Aster sedifolius is quite prevalent in ungary (on Tisa river Basin) [Soo, 19; So, 19; Borhidi, 199; Borhidi, 200; Makra, 2001, from where they described an association, namely: Peucedano-Asteretum sedifolii So 19 corr. Borhidi 199 (syn.: Peucedano- Asteretum punctati So 19). That association has as a characteristic species - Peucedanum ofzcinale, which is a constant species, and at the same time is also a co-dominant for that association (having as companions: Aster sedifolius and Festuca pseudovina). t is thought that these kinds of vegetal communities are the most characteristic ones for the halophylous vegetation situated in the vicinity of the oak forest in ungary [Demeter & Veen 2001; Makra & Zalatnai n the vegetation of Romania, $erbhescu (19) cited from the Romanian Plain "an association with Aster sediflium", without any other eplanations, but two years later (19), the same author, in a synthesis paper on halophylous vegetation from the Romanian Plain, not to mention anything about this "association" (!). Pop (19) described another association, namely: Peucedano-Festucetum pseudovinae, characteristic for the poorly halophylous soils from Crigana, situated at the edge of the oak forests; there, Aster sedifolius is a constant species (being present in.% of its relevkes), but with a reduced coverage (AD = + - 1). Peucedanum ofjicinale and Festuca pseudovina are characteristic and co-dominant species. Through the floristic structure, as well as their ecology, those plant communities described by Pop (19) can be registered, as a matter of fact, under the name Peucedano-Asteretum sedifolii So 19 corr. Borhidi 199 (even Pop, in 19, said that his newly described association "is also known under the name of Peucedano-Asteretum punctati Sod "! ). Later, those semi-halophylous communities where Aster sedifolius plays an important role as a constant, dominant and co-dominant plant, together with Peucedanum ofzcinale (as a characteristic one) and Festuca pseudovina (as a codominant one), have been cited under various names (e.g. Peucedano-Festucetum

3 Phytocoenotic role of Aster sedifolius in Eastern Romania 1 pseudovinae (Rapaics 192) Pop 19; Peucedano-Asteretum punctati Sob 19, Peucedano-Festucetum pseudovinae (Rapaics 192) Pop 19 asteretosum punctati (. Serbgnescu 19) Sanda, Popescu et Doltu 190) fi-om Transylvania, Banat or Muntenia [rigore, 19 1; Karicsonyi, ; Pop, 2000; Sanda et al., 190; Sanda et al., 199; Sanda, 2002; Sanda et Popescu, 2000; Sanda et al, ; Sanda et Popescu, 2001, but not from Moldavia [Chifu et al., We have identified in the latest years, in the Eastern part of Romania (Moldavia), certain semi-halophylous phytocoenoses edified by Aster sedfolius. n the structure of these communities, Peucedanum oficinale is missing at all (moreover, this plant is very rare in this part of Romania, being cited only in few localities from the Southern part of this historic province, namely in alati county [Mititelu et al., 199; Oprea, 200; Chifi et al., 2001). On the other hand, in the structure of the plant communities identified by us, an important phytoceonotic role is played by other two species: Silaum silaus and Artemisia pontica. Festuca pseudovina is a subconstant species, together with Achillea setacea (another subconstant species) and A. collina (a constant species). From the floristic structure and ecologic point of views, these kinds of communities could be framed like this: C1. Puccinellio-Salicornietea Topa 199, Ord. Puccinellietalia So 19 em. Vicherek 19, A1 Festucion pseudovinae So 19, Ass. Achilleo-Festucetum pseudovinae (Magyar 192) So (19) subass. asteretosum sedifolii subass. nova (see Table ). MATERAL AND METODS The methodology applied in this study follows the Central European Phytocoenotic-Floristic School principles, and the working methodology is that one proposed by J. Braun-Blanquet et Pavillard, improved by R. Tiien,. Ellenberg, etc. [Braun-Blanquet, 19; Borza et Boycaiu, 19; Cristea et al., We have made field investigations on stationary. The surface of the relevees varies between 0 and 100 square metres. The botanical nomenclature is according to Ciocklan V. (2000). RESULTS AND DSCUSSON Chorology and local conditions. Phytocoenoses edified by Aster sedfolius, fi-amed by us in ass. Achilleo-Festucetum pseudovinae (Magyar 192) So (19) 19, subass. asteretosum sediflii subass. nova, have been identified by us in the net localities: Cotnari, ayi county (on Paraclis hill), Miroslava, qi county (in the point called "La Cicani?i', near the forest called "onaycu"), Vulturi-Popricani, aai county, and in the forest Balta, between the villages Munteni and Berheci, alati county.

4 Table Ass. Achilleo-Festucetumpseudovinae, (Magyar 192) Sob (19) 19, subass. asteretosum sedifoii subass. nova Coverage (%) rl Surface (sq. m) K Aspect N N N N N N N N - S El. flor Fb UTR V V V E E E E E E Slope (degrees) No. rel. 1 2 *910 chari Eur. cont. 2 chillea collina cont. estuc~~seudovina cont. 2 chillea setacea D$ subass. cont. V cont V V vinae et Puccinellietalia + - A

5 Phvtocoenotic role of Aster sedifolius in Eastern Romania Table (continued) ont.-medit.-eur. centr.. ur. centr. and West onica orchidea

6 Cosm. Cosm. Cosm. cont. Eur. Eur. centr. Eur. Eur. centr.-submedit. Eur. centr.-submedit. Ch Eur. centr.-se Eur. (submedit.) Circ. cont. Eur. centr. Eur. Eur. Eur. centr. Circ. Ch Trif Ch t Ch 2 2 olio-eranietea? 9 9 Rhamno-Prunefea Ph Crataegusmonogyna Ph Ph osa canina runus spinosa Ph Cornus sanguinea Artemisietea Loliumperenne Lysimachianummularia Phleumpratense Potentilla anserina Prunella vulgaris Rume confertus Rume obtusifolius Trifolium repens Vicia cracca Peucedanumalsaticum alium verum Fragaria viridis Veronicachamaedrys Ranunculus polyanthemos subsp. polyanthemoides Coronilla varia Agrimonia eupatoria alium molugo Stachys oflcinalis Teucrium chamaedrys Dorycnium pentaphyllum Senecio erucifolius Serratula tinctoria Knautia awensis Asparagus oflcinalis Clinopodium vulgare Lavatera thuringiaca Viola hirta Clematis recta 1: Daucus carota Elymus repens Tanacetum vulgare,artemisiaabsinthium Table 1 (continued) V l V V v W V l V V 111

7 Phytocoenotic role of Aster sedifolius in Eastern Romania buras. cont. Eur. centr.-medit. t t t t Table 1 (continued) l 1 t Berteroa incana cont Eur Euras submedit. Medit Euras Medit. Cosm. Eur. cont. Medit. (submedit.) Cosm. T T T T Aliae 10? 9? Cichon'um intybus Medicago lupulina Melilotus ofjcinalis Dipsacuslaciniatus Linaria vulgaris Picris hieracioides Lathyrus tuberosus Vicia sativa Phragmitesaustralis Dianthus armeria? Atriple oblongifolia Cirsium awense Matricaria perforata? Trigonelacaerulea Valeriana ofjcinalis Convolvulusarvensis Care riparia - i Date and place of relevtes: 1- Paraclis ill at Cotnari, agi county (1'' of July, 2000); - Miroslava, qi county (1'~ of June, 2002; 'h of October, 2002); 9 a clearing in the forest Balta, alati county (10' of September, 200); 10 Vulturi-Popricani, agi county (11" of September, 200) *- nomenclatural relev type n the above mentioned localities, the phytocoenoses with Aster sedifolius develop small islands, measuring in some cases even hundreds of square meters, with a coverage of the soil between % and 9%, on slopes with some landslides processes, on North-East, North-West or South-East eposures and declivities between ' and 20' (at Cotnari, Miroslava and Vulturi-Popricani), with saltiferous soils of slopes (having saltiferous marls in substrate). n some places, these phytocoenoses are located on flat areas, like on the inferior course of the Barlad

8 C. Siubu, A. Oprea river (in the forest "Balta", between the villages Munteni and Berheci, ala$ county), where the soils are alluvial and salinized (Fig. 1). Fig. 1. A phytocoenosis with Aster sedifolius in the forest "Balta" between Munteni and Berheci (alati county). The phytocoenoses with Aster sedgolius are developing in the vicinity of the bushes (belonging to the ass. Arctio-Ballotetum nigrae (Felfoldy 192) Morariu 19 subass. prunetosum spinosae So 19 1 (at Cotnari and Vulturi-Popricani) and to the ass. Pruno spinosae-crataegetum ueck 191 (at Miroslava), or in the clearings of the forest within the ass. Fraino pallisae-quercetum pedunculzjlorae (Popescu et al. 199) Oprea 199 (the forest "Balta", alati county). Floristic structure: we register a number of 12 vascular plant species in our communities (see Table ). The characteristic plants of this association (namely, Achillea setacea, A. collina and Festuca pseudovina) though they have a relatively higher constancy they have small values of coverage (111-V+-') in our phytocoenoses. The dominant species in our phytocoenoses, Aster sedgolius (a mesophylous, meso-halophylous species, having an Eurasian-Continental distribution area), besides Silaum silaus (a mesophylous - meso-hygrophylous, tolerant halophylous - meso-halophylous species, having an European distribution area) and Artemisia pontica (a eromesophylous - mesophylous, optional halophylous species, having an Eurasian- Continental distribution area), have a constant presence in the phytocoenoses structure. These species are designated as differential species of the newly described subassociation (subass. asteretosum sedifolii subass. nova). Thus, against the type association Achilleo-Festucetum pseudovinae (Magyar 192) So (19)

9 Phvtocoenotic role of Aster sedifolius in Eastern Romania 19, these newly described communities of Aster sedifolius are differentiating through (ero-) mesophylous and oligo-mesohalophylous features, reflected by all these three species, designated by us as being differential ones (Aster sedifolius, Silaum silaus, and Artemisia pontica). Besides the above mentioned species, from among the characteristic higher coenotaa (for alliance, order, class) in our phytocoenoses appear, constantly or subconstantly, the net ones: nula britannica, Juncus gerardi, and Limonium gmelinii. Besides the so-called characteristic species for the class Puccinellio- Salicornietea, in the floristic structure of our phytocoenoses are to be met, also, certain tolerant-halophylous species, which belong from the phytocoenotic point of view to other vegetation classes, as they are: Cynodon dactylon, Agrostis stolonifera, Althaea oficinalis, Potentilla reptans, Lolium perenne, Lotus corniculatus, Lysimachia nummularia, Trifolim repens, Melilotus oficinalis, Cichorium intybus, Matricaria perforata, Trigonella caerulea, Plantago lanceolata, Phragmites australis and so on. On the whole, the ratio of the plants with different halophytic degrees (i. e. tolerants, preferants, obligates) in our phytocoenoses is about % ( species). Because the communities dominated by Aster sedifolius are installed on relatively dry soils during the summer time, but moist in the spring time, thanks to the presence of the ground water near the surface of the soil (fact proved by the actively landslides), in the floristic structure of these phytocoenoses are frequent both some erophylous - eromesophylous species from the class Festuco- Brometea (e. g. Festuca valesiaca, Filipendula vulgaris, Salvia nemorosa and so on) and some mesophylous (even meso-hygrophylous) species from the class Molinio-Arrhenatheretea (e. g. Poa pratensis, Centaurea jacea, Dactylis glomerata, Agrostis stolonifera and so on). The vicinity of the bushes and forests to our phytocoenoses cause the getting in the numerous plants, characteristic for other vegetation classes, such as: Trifolio- eranietea (Peucedanum alsaticum, alium verum, Fragaria viridis, Veronica chamaedrys and so on) or Rhamno-Prunetea (Crataegus monogyna, Rosa canina, Prunus spinosa) and so on. The anthropogenic influence is felt in the phytocoenotic structure by the participation of numerous characteristic species for the class Artemisietea vulgaris; amongst the most frequent species are the net ones: Daucus carota, Elymus repens, Tanacetum vulgare, etc. All these floristic interferences impress to the structure of this newly described subassociation a pretty heterogeneous phytocoenotic feature, like in the case of the association Peucedano-Asteretum sedifolii Sob 19 con. Borhidi 199

10 C. S^rbu, A. Oprea 10 (Syn.: Peucedano-Festucetum pseudovinae (Rapaics 192) Pop 19). Against this one, the communities dominated by Aster sedifolius identified by us in Moldavia are differentiated, generally speaking, by the lack of the species Peucedanum ofjicinale, as well as by the presence with higher constancy indees of the net species: Silaum silaus, Artemisia pontica, Peucedanum alsaticum, and alium verum. The vertical structure. n the phytocoenoses structure, one can distinguish three layers, namely: - a superior one (90-10 cm in height, rough-east, with a coverage to 1%, edified by Peucedanum alsaticum, Tanacetum vulgare, Silaum silaus and some bushes from the neighborhoods, like: Crataegus monogyna, Prunus spinosa, and Rosa canina; - a middle layer, of 0-0 (-0) cm in height, the best developed one, having a coverage of 0-90%, edified, mostly, by Aster sed$olius; besides this species are others, like the net ones: Daucus carota, Elymus repens, Artemisia pontica, Poa pvatensis, Centaurea jacea, alium verum, Achillea collina, nula britannica, Agrostis stolonifea and so on; - an inferior layer, of 1-0 cm in height, having a coverage of 1&1%, better coagulated in those spaces where the individuals of Aster sedifolius are more scarcely distributed, and where is to be met, in most cases, the net species: Plantago lanceolata, Festuca valesiaca, Achillea setacea, Festuca pseudovina, Care praeco, Veronica chamaedrys, Medicago lupulina, Fragaria viridis and so on. n the live's form spectrum one can distinguish an obvious dominance of hemicryptophyte species (0.%), which suggests a well pronounced stability of these phytocoenoses in the surveyed territory. The net categories are represented by therophytes (12.%), geophytes (11.%), hemitherophytes (.%), phanerophytes (.1%) and chamaephytes (.1 %). The phytogeographic spectrum is dominated by the Eurasian elements (.1%); besides this category, one can put into evidence the so-called European elements (1.%), while other floristic elements are poorly represented: Pontic in general (.%), Mediterranean (.2%), Circumpolar (.%), and Cosmopolite (.%). The ecologic spectrum. All the phytocoenoses of this newly described subassociation have general mesophilous, meso-thermophilous and neutrophilouspoorly basiphilous features. The values of the ecologic indees are the net ones: Um=.; Tm=.0; Rm=.1. A pretty higher proportion of the plant species has a large tolerance against the temperature ( species, i.e. 2.%) and the soil acidity (p) (9 species, i.e..%); other 1 species (12%) are largely tolerant against

11 11 Phytocoenotic role of Aster sedgolius in Eastern Romania 9 the soil supply with water. Moreover, as we already mention above in the tet, ca. % apart of the species in our phytocoenoses proves, in various degrees, the halophylous features. Physiognomy. The spring appearance of our phytocoenoses is dominated by the dry stems of the dominant species (Aster sedifolius) remained from the last year. During the summer time, the vegetation cover becomes more tight, with the growth of the stems in the current year, alongside with numerous other species, which round up the floristic structure. The most characteristic appearance is toward the end of the summer, while the dominant species is blossoming; thus, the vegetation cover becomes blue in color, due to the color of the very numerous anthodia; a little later, at the hition of Aster sedifolius, the vegetation cover is changing the color, becoming whitish, due to the papus of the fruits (achenas). We consider the relev no. as a relevk type for this subassociation (see rable ). CONCLUSONS - t is analyzed the role of the species Aster sedifolius in the edification of some meso-halophylous vegetal communities, unknown in the Eastern part of Romania (Moldavia) until now; - On the basis of our surveys, presented in an analytical table (Table l), it is made a comple analysis of those plant communities, framed out like this: C1. Puccinellio-Salicornietea Topa 199, Ord. Puccinellietalia So 19 em. Vicherek 19, Al. Festucion pseudovinae So 19, Ass. Achilleo-Festucetum pseudovinae (Magyar 192) So (19) 19, subass. asteretosum sedifolii subass. nova. REFERENCES 1. Borhidi A., 199, An adnotated checklist of the ungarian plant communities.. The non-forest vegetation. Critical revision of the ungarian plant communities. Janus Pannonius University, Pecs, Borhidi A., 200, MagyarorszLig novnytcirsullisai. AkadCmiai Kiado, Budapest.. Borza Al. & Bogcaiu N., 19, ntroducere in studiul covorului vegetal. Bucure~ti: Edit. Acad. Romhe.. Braun-Blanquet J., 19, Pflanzensoziologie (Ed. 111). Wien-New York.. Bucur N., Dobrescu C., Turcu h., Liandru h. & Tegu C., 190, Contribu!ii la studiul halofiliei plantelor din ppi gi nete de siirilturg, din depresiunea Jijia-Bahlui (partea a 11-a). Stud. Cerc. $ti., ser. Biol. $ti Agr., Acad. R. P. Rorndne, ll(2): -.. Ciocklan V., 2000, Flora ilustratii a Rorndniei. Pteridophyta et Spermatophyta. Bucure~ti: Edit. Ceres.. Chifu T., Mfbu C. & Zamfirescu O., 200, Flora gi vegetatia Moldovei (Rorndnia) agi: Edit. Univ. "Aleandru oan Cuza", +9 pp.

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