Vegetation, hydrological, and morphological dynamics of natural islands in the Danube Delta

Chirilă, Simona Dumitrița; Bănescu, Alexandru; Trifanov, Cristian; Doroftei, Mihai; Covaliov, Silviu

doi:10.3986/hacq-2025-0019

Figures & Tables

Study areas.Slika 1: Preučevana območja.

Dendrogram of vegetation data obtained from cluster analysis.Slika 2: Dendrogram vegetacijskih podatkov, narejen s klastrsko analizo.

Variation of hydrological measurements in the analyzed areas.Slika 3: Variacija hidroloških meritev na preučevanih območjih.

The location of the study’s islands along the lower Danube River – islands morphodynamics.Slika 4: Lokacija preučevanih otokov ob spodnjem teku reke Donave – morfodinamika otokov.

Results of hydrological measurements_Tabela 2: Rezultati hidroloških meritev_

	Location	Spring	Summer	Autumn	Winter
Water level measured in the field (m rMN75)	Isaccea	2.86	2.73	3.36	4.12
		2.86	2.73	3.36	4.12
		2.86	2.73	3.36	4.12

	Dunavăț	1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23
		1.17	1.07	1.74	2.23

	Dranov	0.97	0.87	1.54	2.00
		0.97	0.87	1.54	2.00
		0.97	0.87	1.54	2.00
		0.97	0.87	1.54	2.00
		0.97	0.87	1.54	2.00

Flow measurements (m³/s)	Isaccea	6052	5876	7171	7859
		6034	5858	7149	7793
		6083	5906	7207	7867

	Dunavăț	17	16	26	32
		10	9	15	19
		15	14	23	29
		18	17	27	35
		16	15	24	31
		2314	2143	3463	4438
		2355	2181	3524	4517

	Dranov	574	508	825	1089
		356	315	517	637
		344	304	498	612
		368	326	537	662
		23	20	33	37

Average water velocity (m/s)	Isaccea	0.68	0.66	0.81	0.88
		0.75	0.73	0.89	0.96
		0.95	0.92	1.13	1.22

	Dunavăț	0.36	0.34	0.55	0.67
		0.32	0.3	0.49	0.62
		0.19	0.18	0.29	0.37
		0.29	0.27	0.43	0.55
		0.11	0.1	0.16	0.21
		0.81	0.75	1.21	1.55
		0.87	0.81	1.31	1.67

	Dranov	0.14	0.13	0.2	0.27
		0.47	0.43	0.69	0.85
		0.51	0.46	0.75	0.91
		0.49	0.45	0.73	0.89
		0.22	0.20	0.32	0.36

Riverbed profiles (m)	Isaccea	−6.52	−6.60	−6.68	−6.50

	Dunavăț	−3.12	−3.15	−3.19	−3.19

	Dranov	−3.87	−3.99	−3.95	−3.97

Synoptic table of the percentage frequencies of plant species in the analyzed communities_Tabela 1: Sinoptična tabela preučevanih združb in pogostosti rastlinskih vrst v odstotkih_

No. cluster	Phi	1	2	3	4	5	6	7

No. relevés		2	1	1	1	1	1	13
Cluster 1: Salicetum albae: amorphoetosum fruticosae
Brachypodium sylvaticum (Huds.) P. Beauv.	0.688	50	.	.	.	.	.	.
Digitaria sanguinalis (L.) Scop.	0.688	50	.	.	.	.	.	.
Fumaria officinalis L.	0.688	50	.	.	.	.	.	.
Helianthemum nummularium (L.) Mill.	0.688	50	.	.	.	.	.	.
Aristolochia clematitis L.	0.577	100	100	.	.	.	.	15
Vitis vinifera L.	0.454	100	100	100	.	.	.	23
Fraxinus pennsylvanica Marshall	0.444	50	100	.	.	.	.	.
Glechoma hederacea L.	0.444	50	.	.	.	.	.	8
Potentilla reptans L.	0.444	50	.	.	.	.	.	8
Cluster 2: Convolvulo-Agropyretum repentis
Urtica dioica L.	0.793	.	100	100	.	.	.	8
Dactylis glomerata L.	0.688	.	100	.	.	.	.	.
Drymochloa sylvatica (Pollich) Holub	0.688	.	100	.	.	.	.	.
Elytrigia repens (L.) Nevski	0.688	.	100	.	.	.	.	.
Hordeum murinum L.	0.688	.	100	.	.	.	.	.
Lolium perenne L.	0.688	.	100	.	.	.	.	.
Potentilla recta L.	0.688	.	100	.	.	.	.	.
Fraxinus angustifolia Vahl	0.577	50	100	100	.	.	.	15
Acer negundo L.	0.509	50	100	100	.	.	.	23
Cirsium arvense (L.) Scop.	0.454	50	100	100	100	.	.	23
Sonchus asper (L.) Hill	0.454	50	100	100	.	.	.	31
Vitis vinifera L.	0.454	100	100	100	.	.	.	23
Agrostis capillaris L.	0.444	.	100	.	.	.	.	8
Bromus hordeaceus L.	0.444	.	100	.	.	.	.	8
Fraxinus pennsylvanica Marshall	0.444	50	100	.	.	.	.	.
Cluster 3: Rubo caesii-Salicetum albae
Chenopodium album L.	0.577	.	.	100	.	.	.	31
Cluster 4: Bolboschoenetum maritimi
Bolboschoenus maritimus (L.) Palla	1.000	.	.	.	100	.	.	.
Carduus acanthoides L.	1.000	.	.	.	100	.	.	.
Carex elata All.	1.000	.	.	.	100	.	.	.
Phalaroides arundinacea (L.) Rauschert	1.000	.	.	.	100	.	.	.
Polygonum aviculare L.	1.000	.	.	.	100	.	.	.
Rorippa austriaca (Crantz) Besser	1.000	.	.	.	100	.	.	.
Althaea officinalis L.	0.688	.	.	.	100	.	.	8
Convolvulus arvensis L.	0.688	.	.	.	100	.	.	8
Myosotis scorpioides L.	0.546	.	.	.	100	.	.	15
Plantago major L.	0.546	.	.	100	100	.	.	8
Cluster 5: Glycerietum maximae
Azolla filiculoides Lam.	0.459	.	.	.	100	100	100	8
Glyceria maxima (Hartm.) Holmb.	0.459	.	.	.	100	100	.	15
Cluster 6: Lemno-Azolletum filiculoides
Potamogeton natans L.	1.000	.	.	.	.	.	100	.
Azolla filiculoides Lam.	0.459	.	.	.	100	100	100	8
Cluster 7: Salicetum albae
Phragmites australis (Cav.) Steud.	0.798	.	.	.	100	.	.	62
Stachys palustris L.	0.698	50	.	.	.	.	.	54
Calamagrostis arundinacea (L.) Roth	0.638	.	.	.	.	.	.	38
Salix cinerea L.	0.638	.	.	.	.	.	.	38
Solanum dulcamara L.	0.596	50	.	100	.	.	.	85
Jacobaea paludosa (L.) G. Gaertn. & al.	0.553	.	.	.	.	.	.	31
Populus alba L.	0.553	.	.	.	.	.	.	31
Sium latifolium L.	0.553	.	.	.	.	.	.	31
Typha angustifolia L.	0.553	.	.	.	.	.	.	31
Symphytum officinale L.	0.504	50	.	.	.	.	.	38
Alisma plantago-aquatica L.	0.464	.	.	.	.	.	.	23
Lemna minor L.	0.464	.	.	.	.	.	.	23
Lemna minuta Kunth	0.464	.	.	.	.	.	.	23
Lycopus europaeus L.	0.414	50	.	.	100	.	.	69

Vegetation, hydrological, and morphological dynamics of natural islands in the Danube Delta

Figures & Tables

Figure 1:

Figure 2:

Figure 3:

Figure 4:

Results of hydrological measurements_Tabela 2: Rezultati hidroloških meritev_

Synoptic table of the percentage frequencies of plant species in the analyzed communities_Tabela 1: Sinoptična tabela preučevanih združb in pogostosti rastlinskih vrst v odstotkih_

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