Annual of Natural Sciences Department

Editorial

2025-03-19T11:13:21+00:00

2025-03-19T11:20:32+00:00

Mobile amateur applications for marking and tracking birds as a tool for protecting them and for development of ornithological tourism

2025-03-19T11:33:30+00:00

In terms of avifauna richness, Bulgaria ranks second in Europe after Spain, which makes it an interesting destination for ornithological tourism. The development of mobile technologies has made it easier to record and track ornithological observations and create databases for them. In this study, a selection of mobile amateur applications for bird marking and tracking has been made, and the usefulness of their databases is discussed both for bird conservation and for tourism purposes.

Data analysis of the mid-winter census of wintering aquatic birds on the territory of Ramsar sites along the Bulgarian Black Sea coast for the period 2012 – 2021

2025-03-19T11:49:28+00:00

Wetlands along the Bulgarian Black Sea coast are important wintering points for aquatic birds during the winter period, which is why the site is included in the mid-winter census, which is part of ornithological monitoring in our country. Based on the results obtained from it, an assessment of the ornithological status can be made and the environmental factors influencing it can be analyzed.

The purpose of the study is to present a summary and analysis of census data on the species composition and number of waterfowl in the region of the Ramsar sites on the Bulgarian Black Sea coast for the period 2012 – 2021, which will confirm the ecological significance of these sites and the need for their protection.

Data analysis of the observation on spiders (Araneae) diversity in the Bulgarian part of Osogovo mauntain

2025-03-19T12:45:07+00:00

Osogovo Mountain occupies the largest part of the Osogovo-Belasitsa region and is located in its northernmost part. The highest point of the mountain is Mount Ruen (2251 m). In general, the Osogovo Mountain has an asymmetrical character: steep northern slopes, relatively sloping and separated by numerous ridges eastern and southwestern slopes, which is a prerequisite for the presence of rich biodiversity. The aim of this study is to establish the biodiversity (species composition) and more important biological, ecological and zoogeographical features of spiders (Araneae) from the Bulgarian part of the Osogovo Mountain.

Raw material sources and building materials from the Hellenistic period in the vicinity of Mesambria Pontica according archaeological sites

2025-03-19T13:13:47+00:00

The main objective of this paper is to present the building materials used in the construction of dwellings and houses from the Hellenistic period from archaeological sites located in the close vicinity of Messambria Pontica [present day city of Nessebar]. Other main goal is to present the raw material sources that were used in the construction of buildings. Thus among the priority tasks in the reconstruction of the settlement patterns in the research area. Results of analyzes of clay samples and roof tiles are also presented, which indicate the existing of workshops and developed local production during the Hellenistic period.

Application of clay as a sustainable building material. Characteristics of ancient clay plasters - pilot results

2025-03-19T14:29:27+00:00

Clay is a popular traditional material that has been used for the construction of building materials and household objects since time immemorial. Due to its plastic property and capacity to regulate humidity, it was often used in the form of clay plasters. At present, the building sector has become a serious contributor to climate change, thus triggering a need for the use of more sustainable and eco-friendly materials. This paper aims to analyze the characteristics of ancient clay plasters from the Roman age and define their production technology. The reason for this study is that the ancient production recipes of clay plasters are the base for the modern ones. The analytical methods that were used in this research include X-ray fluorescence (XRF) analysis, Powder X-Ray diffraction (PXRD) analysis, Fourier transformed infrared (FTIR) measurements and thermal analysis. It was established that two types of raw clay were used for the clay plasters preparation, calcareous and non-calcareous, and both match the rock types on the surface around the archeological sites, meaning that the clay was most likely of local origin. There are no signs of burning on the samples; however there is a high probability that they were intentionally treated thermally within a similar temperature range. The acquired results suggest a good environmental knowledge throughout the Roman era and an ability to work well with traditional materials, but with different properties. The results are also of practical value, since they can be applied in the creation of modern plasters that can be used both in modern buildings and for conservation and restoration purposes.