VOLUM OMAGIAL - Facultatea de Ştiinţe ale Naturii şi Ştiinţe Agricole

A characteristic of model habitatas in South Dobrudja /Ovidius University Annals, Biology-Ecology Series 14: 33-44 (2010)
The anthropophytes are 65 species (73.86%).
The high number is due to the artificial origin of the
habitat and adjacent to farmland.
The anthropogenic influence due to the presence
of: 1. Improved access to the habitat by a system
roads. 2. Pollution by garbage from the shepherds and
farm workers. 3. Arable land in the vicinity.
HABITAT 10
Forest shelter belt formed by Robinia
pseudoacacia L.
It is located as a first shelter belt east of the
highway between Durankulak village and Durankulak
Checkpoint, municipality Shabla. The average
altitude is 20 m. The first half of the shelter belt is
oriented in a west – east direction. The second half of
the shelter belt is oriented in a northwest – southeast
direction. The territory has no inclination. The area is
15 dka. The length of the shelter belt is 1 000 m, the
width – 15 m, and the height – 7 m. The soil type is
Leptosols, and the soil subtype is rendzic Leptosols.
The bedrock is limestone. The cover of
the tree vegetation is 60%, the cover of the shrub
vegetation is 10% and the cover of the herbaceous
vegetation is 80%.
In the shelter belt have been indetified 48 species
of vascular plants from 40 genera and 19 families. It
is the most poor of plant species from the shelter
belts. The families with greatest number of genera are
as follows: Asteraceae – 9 (22.50%) and Рosaceae –
5 (12.50%). The families with greatest number of
species are as follows: Asteraceae – 10 (20.83%),
Рosaceae – 7 (14.58%) and Rosaceae – 6 (12.50%).
The genera with greatest number of species are as
follows: Prunus – 3 (6.25%), Artemisia, Elymus,
Euphorbia, Fraxinus, Galium, Lamium and Poa –
with 2 species each of them (4.17%).
With the highest percentage of coverage (4) is
Robinia pseudoacacia L., followed by species
Elymus repens (L.) Gould. and Elymus hispidus
(Opiz) Meld. (3) and Poa pratensis L. (2а). With the
lowest percentage of coverage (1) are 16 species.
Each of the remaining 28 species has coverage 2m.
The perennial herbaceous plants (p) are most –
they are 19 species (39.58%). Secondly, are annual
herbaceous plants (a) with 9 species (18.75%).
Thirdly, are the trees (t) with 6 species (12.50%). The
next are the shrubs (sh) and the transition group of
42
shrubs to trees (sh-t) with 4 species each of them
(8.33%). The transition group of annual to biennial
herbaceous plants (а-b) has 3 species (6.25%). The
biennial herbaceous plants (b) are 2 species (4.17%).
The transition group of biennual to perennial
herbaceous plants (b-р) has one species (2.08%) only.
The largest number of species (19) has
circumboreal origin. Secondly, are species with
Mediterranean origin (10). The next are species with
european origin – they are 7 species. The
cosmopolitan are 4 species. Three species have
Pontic origin. Three of the species are adventive
elements. One of the species has Oriental-Turanian
origin. One of the species is Balkan subendemite –
Carduus candicans Waldst. et Kit.
In the habitat is meeting once Tertiary relict –
Fraxinus excelsior L. Its coverage is less than 5%.
The number of individuals is in the range 6 – 50. The
reason for its presence can be traced in the
transference of fruit from neighboring areas.
One species with protection statute is established
– Artemisia pedemontana Balb. It is included in
IUCN Red List for Bulgaria in the category
„Endangered”, in the Red book for Bulgaria in the
category „Threatened with extinction” and in the
Biological Diversity Act in the category „Protected”.
Its presence can be explained by the transfer of the
fruits by wind and finding favorable conditions,
associated with good light in the shelter belt.
The anthropophytes are 42 species (87.50%).
Extremely high number of them due to the artificial
origin of the habitat and adjacent to farmland.
The anthropogenic influence due to the presence
of: 1. Improved access to the habitat by a system
roads. 2. Arable land in the vicinity.
4. Conclusions
From natural habitats are established most
taxonomical diversity in Western Pontic Paeonian
steppes near to Bejanovo village, and least
taxonomical diversity in Rupicolous calcareous or
basophilic grasslands of the Alysso-Sedion albi
between Onogur and Efreitor Bakalovo villages.
From forest shelter belts are established most
taxonomical diversity in Forest shelter belt formed by
Gleditsia triacanthos L., and least taxonomical
diversity in Forest shelter belt formed by Robinia