Agroecosystems include those lands used for the production of different crops such as cereal crops, fruit and vegetables, technical crops, which are cultivated crops or agricultural produce, source of food or feed, for the production of fiber, vegetable fats, or as an energy source.
In the Danubian Plain they occupy the greatest relative share due to the appropriate relief, climate, and soils that have led to the development of intensive agriculture.
Despite the significant human impact that has shaped the agroecosystems, they are important for maintaining biodiversity. One example are the populations of wintering birds, such as the red-breasted goose finding food in the winter in the Dobrudzha fields. For that reason, protected areas such as Zlatia, Nikopol Plateau and Kraymorska Dobrudzha include large areas of arable land.
Grassland ecosystems refer to natural or semi-natural types of vegetation. They include dynamic biological groups of different plant species, combined with biological groups of farm animals, flora, fauna, soils, water, and atmosphere. They are part of the farms (pastures, meadows, hedges, buffer zones, non-farm land, etc.).
Located inhomogeneously in the area of study, grassland ecosystems form more significant groups along all plain rivers, the slopes of river valleys, the highlands of hills and plateaus. Natural grasslands, although now in small polygons, are of great importance to maintain plant and animal diversity.
Shrub and ericoid ecosystems
In the area of study, there are predominantly riverside and marshland shrub ecosystems. These are shrub facies on the banks of rivers, lakes, and wetlands, where tree and shrub species don’t exceed 5 meters in height. Originally, these facies are of a generic nature. Dominant species are Tamarix ramosissima, T. tetrandra, Salix fragilis, S. purpurea, etc.
Such facies are mostly spread around the Danube River and the large tributaries – Ogosta, Iskar, Vit, Osam, and Yantra.
The Black Sea coast is included in the easternmost part of the cross-border region. Marine ecosystems are subdivided into (a) sea water, the associated bottom and its subsoil along the seaward side from the line from which the territorial waters are measured to the most border zone where the country has and/or exercises its jurisdiction in accordance with the UNCLOS (the United Nations Convention on the Law of the Sea); and (b) coastal waters under the Water Framework Directive (Directive 2000/60/EC), the associated bottom and its subsoil.
Ecosystems in areas with sparse or no vegetation
These ecosystems often have extreme natural conditions where only specific species can be found. This type of ecosystems include bare rocks, screes, dunes, beaches, and sand plains.
Larger areas of bare rocks are found in the sites of Belogradchik rocks, Vratsa Balkan, Karlukovo karst, Rusenski Lom and the Black Sea coast. Sand, beaches and dunes are spread all along the Danube River as well as in some parts of north Black Sea coast.
Freshwater ecosystems include all rivers and lakes, including artificial water sources, e.g. the large number of dams and irrigation channels. According to the Water Framework Directive (WFD 2000/60/EPC), surface water and groundwater are divided into the so-called “water-bodies”. A water body is an independent and significant part of surface water or groundwater with relatively uniform ecological characteristics.
Many of the rivers and lakes in the scope of the study are classified as different categories of protected areas and NATURA 2000 protected areas due to the environmental roles they perform. The Danube and its larger tributaries are important ecological corridors with connecting function significant to the distribution and migration of protected species.
Wetland ecosystems are dynamic facies of different plant species, fauna, soils, water, and atmosphere. This type of ecosystem is very vulnerable and fragile because it entirely depends on the presence of a permanent water source.
The most significant wetlands in Bulgaria are described in the National Plan for the Protection of the Most Important Wetlands in Bulgaria 2013-2022. A part of them have been proclaimed wetlands of international importance within the meaning of the Ramsar Convention. Such sites in the area of study are Belene Islands Complex, Ibisha Island, Srebarna, Durankulak Lake, and Shabla Lake.
Forest ecosystems include natural forests and forest crops with predominant tree vegetation. They are subdivided into deciduous, coniferous, and mixed.
In the area of study, the most significant forest massifs are located in the mountain and hill terrains: Western Balkan and Fore-Balkan, Vratsa Balkan, Karlukovo, Tvarditsa Mountains, Rusenski Lom, Ludogorie. Plain and riparian forests along the Danube and its tributaries are smaller in area, but significant for biodiversity conservation.
Urbanized ecosystems include settlements with urban parks and green areas, street landscaping, industrial sites and other terrains that are greatly influenced by man or of artificial origin.
Although urbanized ecosystems differ from natural ecosystems, they also have ecosystem functions and provide ecosystem services. In some cases, settlements are included in the territorial scope of protected areas (nature parks) and NATURA 2000 protected areas.
The area of study covers the areas of the districts located in the border region with Bulgaria, from west to east, Mehedinti, Dolj, Olt, Teleorman, Giurgiu, Calarasi, Constanta. The area has a high tourism potential, but not sufficiently valued.
In Mehedinti County, all kinds of landscape are found – mountains (e.g. Mehedinti Mountains), plateaus (e.g. Mehedinti Plateau), hills (e.g. Deadman’s Hills) and plains (e.g. Plain of Blahnita River). Tourism can be practiced throughout the year thanks to the favorable weather conditions – a moderate continental climate with Mediterranean influence. There are three extremely valuable natural resources in Mehedinti: Iron Gate Nature Park, Domogled Nature Park, the Chernia River valley and the Mehedinti Plateau Geology Park.
The adjacent county is Dolj, where the plain relief is predominant and nature mainly offers plain areas and lakes. The warm and moderate climate with Mediterranean influence gives the opportunity for tourism almost all year-round.
Olt County coprises mostly plain and hill areas, and similar to Dolj County, the climate gives the opportunity for tourism almost all year-round.
Teleorman County is located entirely in the Romanian Valley and the most spectacular landscape is the riverside valley of the Danube. The tourism potential of Teleorman County is only presented through the NATURA 2000 sites located near the Danube River.
Giurgiu County, also located in the Romanian Valley, is distinguished by the presence of the Comana Nature Park, which has already become a recognized tourist attraction. The most suitable periods for tourism are from May to August and in November and December.
Calarasi County is located in the Baragan Valley and it accommodates numerous lakes and marshes. The landscape bordering on the Danube and the Borca branch offers small wild islands, lakes and marshes, which are mostly used for weekend tourism. The tourism potential of the area is high.
In terms of tourists, Constanta County is among the most developed counties in the country. The outlet on the Black Sea is a territory where tourist seaside resorts are concentrated. Also, the plateau relief (the Dobrudzha Plateau) is very rick – there are river gorges, caves, cliffs, rich forests, etc.