VOLUM OMAGIAL - Facultatea de Ştiinţe ale Naturii şi Ştiinţe Agricole

Dimcho Zahariev / Ovidius University Annals, Biology-Ecology Series 14: 33-44 (2010)
The anthropophytes are 45 species (81.82%).
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. 3. Arable land in the
vicinity.
HABITAT 9
Forest shelter belt formed by Gleditsia
triacanthos L.
It is located south of Karapelit village,
municipality Dobrich. The average altitude is 175 m.
The exposure is northeast. The shelter belt is oriented
in a north – south direction. The slope is low and
reaches 10°. The area is 15 dka. The length of the
shelter belt is 1 000 m, the width – 15 m, and the
height – 15 m. The soil type is Chernozems, and the
soil subtype is haplic Chernozems. 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 70%.
In the shelter belt have been indetified 88 species
of vascular plants from 78 genera and 30 families. It
is the richest of plant species from the shelter belts.
The reason for this is that is located immediately
adjacent steppe. From the steppe to the shelter belt
migrated a large number of species. The families with
greatest number of genera are as follows: Lamiaceae
– 11 (14.10%), Fabaceae – 9 (11.54%), Rosaceae – 8
(10.26%), Asteraceae – 7 (8.97%), Poaceae – 6
(7.69%) and Apiaceae – 5 (6.41%). The families with
greatest number of species are as follows: Lamiaceae
– 13 (14.77%), Rosaceae – 11 (12.50%), Asteraceae
– 9 (10.23%), Fabaceae – 9 (10.23%), Poaceae – 6
(6.82%) and Apiaceae – 5 (5.68%). The genus with
greatest number of species is Prunus – with 4 species
(4.55%).
With the highest percentage of coverage (4) is
Gleditsia triacanthos L. Secondly, it is Poa pratensis
L. (2а). With the cover 1 are 23 species. With the
lowest percentage of coverage are Carduus
acanthoides L., Sanguisorba minor Scop. (+) and
Verbascum ovalifolium Sms. (r). Each of the
remaining 60 species has coverage 2m.
The perennial herbaceous plants (p) are most –
they are 42 species (47.73%). Secondly, are annual
herbaceous plants (a) with 16 species (18.18%).
41
Thirdly, are the trees (t) and the shrubs (sh) with 9
species (10.23%) each of them. The next are the
transition group of shrubs to trees (sh-t) and the
biennial herbaceous plants (b) with 4 species each of
them (4.55%). The transition group of annual to
perennial herbaceous plants (а-р) has 2 species
(2.27%). The transition groups of annual to biennial
herbaceous plants (а-b) and of biennual to perennial
herbaceous plants (b-р) are presented with one
species (1.14%).
The largest number of species (28) has
circumboreal origin. Secondly, are species with
Mediterranean origin (21). The next are species with
European (14) and Pontic origin (12). Six of the
species is adventive element. The cosmopolitan are 5
species. One of the species has Oriental-Turanian
origin. One of the species is Balkan endemite –
Achillea clypeolata Sibth. et Sm.
Three species are Tertiary relicts: Celtis australis
L., Cotinus coggygria Scop., Ulmus minor Mill. Each
of them has less than 5% coverage. The number of
Celtis australis L. is less than 50 individuals. The
number of another two species is more than 50
individuals. The reason for their presence can be
traced in the transference of fruit from neighboring
areas.
Four species with protection statute are
established: Adonis vernalis L. is included in CITES
and in the Order for special arrangements for the
conservation and use of medicinal plants in the
category “Collecting herbs is prohibited from the
natural habitats”. Jurinea ledebourii Bunge is
included in the IUCN Red List for Bulgaria in the
category “Endangered”, in the Red book for Bulgaria
in the category „rare” and in the Biological Diversity
Act in the category „protected”. Tilia rubra DC. is
included in IUCN Red List for Bulgaria in the
category „Least Concern” and in the Red book for
Bulgaria in category “Rare”. Asparagus officinalis L.
is included in the the Biological Diversity Act in the
category „Under the protection and regulated use of
nature”.
The presence of Adonis vernalis L. and Jurinea
ledebourii Bunge is associated with their migration
from the nearby steppe region.