Dr. Todor Dimov:

The continental part of Dobroudja, as well as its Black sea coastal area are comparatively dry in comparison to the rest of Bulgaria. In the dry valleys there are currents only at abundant rainfalls or intensive thawing of snows. The Dobroudja coast has sharp temperature amplitudes (variations from -1 to 23^o C) and low precipitation (430 - 480 mm), which increases with the distance from the sea.

The early Holocene vegetation is now destroyed or modified due to the millennial human activities. Scarce spots of it are preserved only in isolated areas. The paleobotanic studies of the lagoons in Shabla and Durankulak carried out in recent years allowed to approximately reconstruct the variability of plant species in the southern part of Dobroudja. They provide the possibility to restore a part of the general paleoecology in the region of the north-western Black sea coast from the beginning of the Holocene till modern times. It is interesting to note the presence of the wild steppe ass (Equus /Hemionus/ hydruntinus danubiensis) in Dobroudja during the Neolithic. Remains from this glacial species have been excavated in large amounts at Durankulak, Tekirgoel, Cherna voda and other archaeological sites. Some wild and domesticated animal species have also been discovered helping to complete the total ecological picture; these are as follows:

a) domesticated species: cattle, swine, sheep, goat and dog;

b) wild species: red deer, roe, wild boar, wild horse, wild steppe ass, rabbit, badger, wolf, traces of birds, turtle and fish. There is also some evidence for the presence of lion, beaver and bear, though in smaller percentage.

The general conclusion is that only in the second half of the 4^th millennium B.C. there already existed a suitable, although not very comfortable environment for exploitation by neolithisation tribes. This circumstance retarded the permanent settlement of the Neolithic man in these regions with over half a millennium.