DSpace 7
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Recent Submissions
Evaluating polystyrene nanoparticle toxicity in eelgrass: impacts on photosynthetic efficiency, oxidative stress, and DNA integrity
(Plovdiv University "Paisii Hilendarski", 2026-05-28) Hienva, Elitsa; Dzhembekova, Nina; Ivanova, Petya; Tsvetanova, Elina; Georgieva, Almira; Alexandrova, Albena; Stamatova, Hristiana
Micro- and nanoplastic pollution is ubiquitous in marine and coastal areas with the potential to impact valuable ecosystems, such as seagrass meadows. One of the important questions in seagrass ecology today is whether micro- and nanoplastics could seriously threaten seagrass health, and which parameters would be the best to observe such impacts. As a part of this research necessity, we have explored the effect of pure polystyrene nanoparticles on the maximum quantum yield of PSII, oxidative stress parameters, and DNA integrity on leaves of Zostera marina L. fragments, under controlled conditions. The three different indicator types are not negatively impacted when eelgrass fragments are subjected to a short time exposure (> 10 days). To find the most responsive indicators for micro- and nanoplastics impacts, further studies on a variety of metrics, operating at different seagrass structure levels and time frames, are necessary.
Overview in representatives of Rumex and Persicaria (Polygonaceae Juss.) in the flora of Bulgaria
(Plovdiv University "Paisii Hilendarski", 2026-04-10) Raycheva, Tsvetanka; Stoyanov, Kiril; Raycheva, Teodora; Karaycheva, Gergana; Mladenov, Rumen; Stoyanov, Plamen
The taxonomy of Rumex L. and Persicaria Mill. has been the subject of revisions for decades. The high morphological similarity between closely related taxa is probably due to a
recent divergence and subsequent process of intensive speciation. As a result, complex species aggregates have formed in the genera Rumex and Persicaria. Hybridization processes, aided by their broad ecological plasticity and adaptation in anthropogenically influenced habitats, are major factors for the dynamic occupation of pioneer sites, with the potential to become aggressive weeds. This requires clarification and knowledge of the species diversity in these groups, which are an important component of the floras of many countries worldwide. As a result of recent studies, new hybrids of the genus Rumex have been discovered for our flora. This is an indication that the number of hybrids is greater than indicated in the summarized
publications on the Bulgarian flora. Furthermore, the lack of taxonomic studies creates a need to reassess the phylogenetic relationships and status of taxa in the polymorphic, non-monophyletic groups of Rumex and Persicaria in our country.
New data on the bats (Mammalia: Chiroptera) of the Drinos Valley, Vjosa Wild River National Park Southern Albania
(Plovdiv University "Paisii Hilendarski", 2026-03-18) Bruhat, Lionel; Olivier, Anthony; Mallet, Pierre; Thibault, Marc
Albania's bat fauna is rich but still poorly studied and subject to numerous pressures. One immediate pressure includes the plans to build hydroelectric dams on the Vjosa River and its tributaries, recently classified as a national park. This study was part of an international movement to improve knowledge of both a taxonomic group and a geographical area that have not been studied extensively, to take them into account for conservation purposes. In June 2022, 15 passive bat acoustic sampling sites were set up in four distinct sectors along the Drinos and Suha Rivers, two tributaries of the Vjosa. The Drinos River was included within the national park boundaries in 2023. These recordings were analyzed using automatic identification software and manually verified. Our study identified 16 of the 32 species known to occur in Albania, of which four had fewer than 25 previous records in Albania: Myotis bechsteinii, Myotis emarginatus, Myotis nattereri, and Rhinolophus blasii. Our results highlight a high level of activity observed at the sampling sites and the importance of alluvial and riparian hydroecosystems for bats. This study supports the need to take bats into account in the management plans and projects of the Vjosa Wild River National Park. It also produced 135 additional bat records for the country, adding to the 1243 national records.
Ecological and technogenic safety and phytomelioration of degraded landscapes of a limestone quarry
(Plovdiv University "Paisii Hilendarski", 2026-04-28) Shukel, Igor; Boiko, Taras; Popovych, Vasyl; Kobko, Yevhen; Nitsevych, Olesia; Kobko, Roman; Korol, Kateryna
The reclamation of degraded lands, particularly limestone quarries, is a critical ecological task aimed at restoring soil cover and forming stable phytocenoses. This study evaluates
the effectiveness of phytomelioration measures through an analysis of changes in the physicochemical properties of soil and plant composition. The results showed that, after reclamation, humus content increased by 15%, contributing to improved soil structure and water retention capacity. Soil acidity (pH) rose from 4.5 to 6.1, creating favorable conditions for the development of mesophytic and eutrophic species. The concentration of macronutrients significantly increased: nitrogen from 12.3 mg/kg to 24.7 mg/kg, phosphorus from 9.8 mg/kg to 20.3 mg/kg, and potassium from 85 mg/kg to 150 mg/kg, positively affecting plant cover productivity. Phytocenosis analysis revealed an increase in meadow-steppe communities from 24.69% to 31.82% and eutrophic species from 22.22% to 34.55%, indicating ecosystem stabilization. The planting of tree species (Pinus sylvestris, Robinia pseudoacacia, Quercus robur) contributed to soil stabilization, reduced erosion processes, and the gradual formation of forest ecosystems. The results confirm the effectiveness of phytomelioration in restoring technogenically disturbed lands. Future research should focus on long-term monitoring of successional changes and the impact of reclamation measures on soil biogeochemical processes.
Linear-weight relationship of the species Carcinus aestuarii Nardo, 1847 (Decapoda: Brachyura: Carcinidae) along the Bulgarian Black Sea coast
(Plovdiv University "Paisii Hilendarski", 2026-05-12) Uzuniva, Sonya; Mitov, Plamen
Aim of the present study was to establish the growth of the decapod crustacean Carcinus aestuarii Nardo, 1847, for the Bulgarian Black Sea area. Biometric measurements of specimens sampled by diving and trawling were compared. Averaged values for carapace length (in cm) of the specimens collected by diving and trawling are relatively similar (4.25±0.856, against 4.92±0.064). Data for carapace mean width varied from 5.56±1.11 to 6.34±0.873 cm. Weight ranged from 8.5 to 167.86 g. Minimal values for size and weight were observed in the specimens collected by diving, and the maximum in the trawl discards. Positive allometric growth was observed in most cases, except for the total pool of discards and, in particular, for male individuals. Further detailed investigations on a monthly and seasonal basis are required to understand the complexity of factors influencing the populations of Carcinus aestuarii and its response to environmental changes.