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Salinisation is an important soil-forming process (primary or secondary), characterized by an excess of water-soluble salts and/or exchangeable sodium. The amount of exchangeable magnesium is also essential for the more detailed determination of the physico-chemical properties of saline soils. The determination of magnesium salinity is still a debatable issue, but there are already criteria in the literature for its estimation. The Belozem region is representative of Bulgaria for the processes of alkaline salinisation, but the presence and extent of magnesium salinity has not been determined. For this purpose, data from ten soil profiles and four criteria for determining magnesium salinity were used. In three of the profiles there is an increased content of exchangeable magnesium, which covers all four indicators of magnesium salinity, in three of the profiles the magnesium salinity is determined only in some horizons and in the other four cannot be clearly defined. The study also showed that the application of all four criteria is necessary in order to make a strong claim for the presence of magnesium salinity.

The study examines the relationships between the beach-face slopes and sediment sizes for several coastal stretches located in Burgas Bay using limited field data, and explores the applicability of a number of previously developed formulations for local geomorphic, lithologic and wave conditions. Knowledge on the clear dependence between considered parameters is of particular importance for many engineering applications such as calculation of maximum run-up, shoreline changes, beach berm erosion potential, and assessment of coastal flood and erosion hazards. The results have shown that none of the considered empirical relationships can be used straightforwardly, although some of them might be considered for future analysis. Hence, it is necessary to enrich the database with wider ranges of beachface slopes, sediment sizes coming from areas with different wave exposure and morphodynamics state in order to elaborate a reliable native relationship suitable for local to regional specifics of the western Black Sea coast. This underpins the importance of regular coastal monitoring., Proceeding of 1st International Conference on Environmental Protection and Disaster RISKs, 2020, p. 405-419

This chapter presents the GIS-based hazard maps that are set-up for the project area in Bulgaria. The maps have been compiled by Professor Fridtjof Nansen Institute of Oceanology - Bulgarian Academy of Sciences. The text herein represents an excerpt from Deliverable 5.1GIS-Based Hazard Maps, WP 5: Early Warning System, project "Morphological Impacts and Coastal Risks Induced by Extreme Storm Events" (Acronym: MICORE), funded under the EU's 7FP, GA No 2002798.

The loess in the Danubian plain is rich of nutrients and there is situated the south border of so called ―corn belt of Europe‖, where are the most fertile soils of Balkan Peninsula. There are five main typical soil types spread over loess - Chernozems, Phaeozems, Kastanozems, Regosols and Calcisols. There is also a big diversity in the content of basic nutrient elements – it varies between low and high content of organic carbon and mobile forms of nitrogen, phosphorous and potassium. As a whole there is shortage of phosphorus in all soil types. Soils over loess are characterized by a surface layer that is rich in organic matter, minerals and nutrients with abundant natural grass vegetation and high fertility soil types such as Chernozems, Phaeozems and Kastanozems. Eroded and shallow soils such as Regosols and Calcisols have low quantities of major nutrient elements as mobile nitrogen, phosphorus, and total organic matter, consequently their fertility is low.