Dobrogea Region Research Articles

Local-scale impact of wind energy farms on rare, endemic, and threatened plant species

BackgroundWind energy farms have become a popular solution to produce green energy worldwide. Their development within protected areas has increased dramatically in the past decade, and the effects on the rare, endemic and threatened plant species (i.e., protected plant species), essential for habitat conservation and management, are little known. Only a few studies directly quantify the impacts of wind energy farms on them. Our study analyzes the impact of wind energy farms on rare, endemic, and threatened plant species in steppic habitats and their recovery potential over a ten-year period on a wind energy farm within the Dealurile Agighiolului Natura 2000 site (Dobrogea Region, SE Romania).MethodsWe surveyed the rare, endemic, and threatened plant species within a radius of approximately 50 m around each of the 17 wind towers during the wind farm operational phase. We selected 34 plots to allow the investigation of two types of areas: (1) a disturbed area overlapping the technological platform, where the vegetation was removed before construction, and (2) an adjacent undisturbed area. To understand the effects of the wind energy farm on the rare, endemic, and threatened plant species diversity and the differences between the disturbed and undisturbed areas, we calculated under both conditions: (1) plant species richness; (2) sample-size-based rarefaction and extrapolation with Hill numbers parameterized by species richness; (3) non-metric multidimensional scaling of Jaccard dissimilarity index; (4) functional diversity; (5) beta-diversity (including replacement and nestedness of species).ResultsAs a result of the disturbances caused by the wind energy farm’s development, we identified a sharp contrast between the diversity of rare, endemic, and threatened plants inhabiting disturbed and undisturbed areas near the wind towers. Our research showed that less than 40% of the total inventoried rare, endemic, and threatened species colonized the disturbed sites. Species turnover within undisturbed plots was higher than disturbed plots, implying that the plant community’s heterogeneity was high. However, a higher richness in rare, endemic, and threatened plant species was found in the plots around the wind towers in grasslands of primary type. Sample-size-based rarefaction and extrapolation with Hill numbers by observed species richness indicated an accurate estimation of species richness in disturbed habitats, demonstrating that recovery after wind energy farm construction was incomplete after ten years of low-intensity plant restoration and conservation activities. Thus, we consider that operating activities must be reconfigured to allow the complete recovery of the communities with rare, endemic, and threatened plant species.

A review of flash floods in the Dobrogea Region

The last decade is characterized by an increase in the occurrence of flash floods, fact which is confirmed by the worldwide endeavors undertaken by the WMO (World Meteorological Association) which initiated the signing of a series of memorandums for collaboration with other worldwide institutions meant to lead to the elaboration and implementing of a complex flash flood warning system. The aim of this paper is to analyze the level of implementation of said system in Europe and Romania and the analysis of the flash flood occurrence, specifically in the Dobrogea region of Romania.

The efficiency of extracting clean energy in the Dobrogea Region of Romania

The aim of this study is to evaluate the efficiency of extracting clean energy in the Dobrogea region of Romania. More precisely was analyzed the wind potential in correspondence with some economical parameters that determines the efficiency of extracting clean energy. For this purpose, a data set that contains wind zonal and meridional components for a period of 20 years was processed. In this study, the data set was downloaded from the European Centre for Medium-Range Weather Forecasts. By analyzing the levelized cost of electricity, the annual energy production, the annual expensive and other parameters it can be easily observed that implementing new project for extracting renewable energy can be efficient.

Analysis of the Arbovirosis Potential Occurrence in Dobrogea, Romania

Climate change creates new challenges for preventing and protecting human health against different diseases that could appear and propagate. The Aedes albopictus mosquito species is an important vector for different diseases like dengue fever or zika. Although this species is not “indigenous” in Europe, its presence is noticed in many countries on the continent. The Ae. albopictus establishment is conditioned by the species’ characteristics and environmental factors. To assess the possible spread of Ae. albopictus in the Dobrogea region (situated in the Southeast of Romania), we conducted the following analysis: (1) Investigation of the current distribution and climatic factors favoring Ae. albopictus’ establishment in Europe; (2) Analysis of climate dynamics in Dobrogea in terms of the parameters identified at stage (1); (3) Testing the hypothesis that the climate from Dobrogea favors Ae. albopictus’ establishment in the region; (4) Building a Geographic Information System (GIS)-based model of the potential geographic distribution of Ae. albopictus in Dobrogea. Results show that the climate of Dobrogea favors the apparition of the investigated species and its proliferation.

Quality and Health Risk Assessment Associated with Water Consumption—A Case Study on Karstic Springs

In rural areas without centralized water supply systems, inhabitants often use groundwater of unknown quality as drinking water, without understanding the possible negative consequences on their health. Karstic spring waters from Dobrogea region in Romania were assessed for their potential to be used as drinking water source, according to their quality and seasonal variation. The physico-chemical parameters of waters were compared with the guideline values for drinking water established by the World Health Organization and the Directive 98/83/EC. The nitrate and Cr concentrations exceeded the guideline value in the springs from Southern Dobrogea, but met the quality criteria in those from Northern Dobrogea, thus, to be used as drinking water, the karstic springs located in Southern Dobrogea require treatment for nitrates removal. Heavy metals pollution indices showed low to medium cumulative heavy metal pollution in all springs, while the human health risk assessment by oral exposure indicated possible noncarcinogenic risks of nitrates, both for adults and children in springs from South Dobrogea. A rigorous monitoring of the water quality before human consumption is recommended for all four studied water sources.

Magnetometric and electrometric investigations in the Beroe submerged archaeologic site

In ancient times, Dobrogea was known as Schythia Minor or Mikra Skythia. In the Ist century BC, the respective territory was under the influence of the Pontic kingdom of Mithridate the VIth Eupator. From 28 BC it was integrated in the Roman province of Moesia Inferior by Emperor Augustus. Most Roman-Byzantine fortresses have been established by the Romans on the site of former Getic settlements: Tropaeum Traiani, Capidava, Carsium, Beroe, Troesmis, Arrubium, Dinogetia, Noviodunum, Ibida, Durostorum. The Roman-Byzantine fortress of Beroe-Ostrov grew around the Roman castrum of Beroe, where the Vth Legion was stationed in the Ist and IInd centuries. One can find here the partially unearthed ruins of a Roman and Byzantine fortress, dating back to the Ist-VIth and Xth-XIIth centuries, and nearby, those of a Paleo- Christian basilica, dating back to the Vth-VIth centuries. The latter is situated aside from the former cemetery, which has been used between the Ist -XIIth centuries. As a result of conflicts between the Dacians of Dobrogea (the Comati) and the Romans, the fortress was destroyed, and was re-inhabited once the Byzantines returned to the Lower Danube, under Emperor Ioan Tzimiskes. The Roman and Byzantine fortress from Beroe is located 3 km to the South of Ostrov village, in North Dobroudja, the north side of Moesia Inferior province. We carried out magnetometric and electrometric measurements in the Beroe archaeological site, located in the Dobrogea region of Romania. We analyzed the results to see if we could find the orientation of the walls or any other evidence of a former human presence within a limited area submerged beneath the Danube River. We showed the estimated depth of the site and the possible orientation of a wall. The geophysical data was acquired on the water (Danube River) within the submerged zone using marine equipment designed for that purpose (G822 device with cesium) with a gradient array and AGI ministing electrometer with 100 m length. The area of investigation was 100 by 50 meters, and it was located in the NE part of the site, having a grid density of 10 by 10 meters. The data we obtained in this study indicates the possible presence of submerged artefacts. Magnetic susceptibility measurements indicate a possible magnetic contrast between the regional geological background (local limestone rocks used in the construction of the fortress walls, mortar, etc.), characterized by low, sometimes even diamagnetic magnetic properties and artifacts such as bricks, backed (fired) adobe, ceramic fragments, showing relatively high magnetic susceptibilities.

Crustal stress partitioning in the complex seismic active areas of Romania

Analyzing the partitioning of stress and deformation in active orogenic settings is of fundamental importance for understanding the mechanisms driving the geodynamic evolution and seismicity, particularly in complex orogenic settings. In this respect, a quantitative understanding is obtained by coupling the large-scale geodynamic evolution with partitioning of local deformation and stress patterns derived from analyzing the seismicity character, focal plane solutions and kinematics of genetically related active structures. The goal of the present paper is to investigate the stress field characteristics in relation with the specific geotectonics and seismogenic zones of Romania. The principal stress components are computed by inverting the fault plane solutions provided by a completed and updated catalogue for the crustal earthquakes recorded since 1929 up to 2012. Our investigation is justified to the extent that the basic hypothesis of properly representing the seismic area partitioning by individual clusters of events is relevant at the scale of each earthquake-prone area and from statistical point of view (minimum 20–30 events). The catalogue covers mostly the area in front of the Carpathians Arc: Moesian Platform, Barlad Depression, North Dobrogean Orogen, Southern Carpathians belt (Făgăras-Câmpulung, Central Southern Carpathian and Danubian seismogenic zones) and western part of Romania (Banat region). The seismicity is sporadic and the available fault plane solutions are less representative for the entire area in the inner side of the Carpathians and for the Dobrogea region, located between Danube river and Black Sea. Therefore, for these last two regions the resulted stress field properties are considered as preliminary. The formal stress inversion applied on groups of focal mechanisms proved to be a better estimation of the tectonic stress orientation that can be achieved in the study region in comparison with single focal mechanism, as shown in the World Stress Map Project 2016.

Preliminary Results in the Study of Two Local Almond Populations from Dobrogea Region

The almond (Prunus dulcis L.) is a very popular nut, being one of the most complex fruits for the benefit of the human health. Nowadays in Romania, this crop started to decrease as covered land and production. At the global level the cultivated surfaces and the production is on raise. The aim of our study was to select better almond genotypes suitable for breeding. The study’s goal was to monitor two spontaneous populations of almond hybrids naturally formed in two distinct localities from the Dobrogea region, namely Greci, from Tulcea county and Crucea, from Constanta county. Naturally formed almond hybrids were studied and observations have been performed for the phenophases in the years 2018 and 2019, also observing the presence of different pathogenic diseases on the phyllosphere of the plants. There were also accomplished morphological measurements for the hybrids of high interest according to the purpose of the present research work.

Wildlife and infrastructure: impact of wind turbines on bats in the Black Sea coast region

In Eastern Europe, wind energy production is currently promoted as an important source of renewable energy, yet in most cases without appropriate consideration of the negative impacts wind turbines (WT) may have on protected species such as bats. Here, we present first data on fatality rates, fatality factors and the likely origin of bats killed by WT in the Dobrogea region (Romania), located in a major migratory corridor for wildlife in Eastern Europe. Over a 4-year period, we found a total of 166 bat carcasses from 10 species, mostly representing migratory species such as Pipistrellus nathusii and Nyctalus noctula. Most fatalities at WT occurred in July and August. We documented 15 cases of barotrauma and 34 cases of blunt-force trauma in carcasses found below WT. After adjusting for carcass removals and variations in searcher efficiency, we estimated for the 4-year study period a total of 2394 bat casualties at the studied WT facility consisting of 20 units, resulting in a mean fatality rate of 30 bats/WT/year, or 14.2 bats/MW/year. By implementing a curtailment measure at wind speeds below 6.5 m/s, we reduced fatality rates by 78%. Isoscape origin models based on hydrogen stable isotope ratios in fur keratin revealed that the majority of N. noctula that were killed by WT or captured nearby in mist nets originated from distant areas in the North (Ukraine, Belarus, Russia). The estimated high fatalitjegangy rates of bats at WT in this area have far-reaching consequences, particularly for populations of migratory bats, if no appropriate mitigation schemes are practised.

Optimizing Inverse Distance Weighting with Particle Swarm Optimization

Spatial analysis of hydrological data often requires the interpolation of a variable from point samples. Commonly used methods for solving this problem include Inverse Distance Weighting (IDW) and Kriging (KG). IDW is easily extensible, has a competitive computational cost with respect to KG, hence it is usually preferred for this task. This paper proposes the optimization of finding the IDW parameter using a nature-inspired metaheuristic, namely Particle Swarm Optimization (PSO). The performance of the improved algorithm is evaluated in a complex scenario and benchmarked against the KG algorithm for 51 precipitation series from the Dobrogea region (Romania). Apart from facilitating the process of applying IDW, the PSO implementation for Optimizing IDW (OIDW) is computationally lighter than the traditional IDW approach. Compared to Kriging, OIDW is straightforward to be implemented and does not require the difficult process of identification of the most appropriate variogram for the given data.

Parametric method used for mapping the groundwater vulnerability to contamination

Groundwater is a natural resource indispensable for life and for most economic activities. Due to its presentation in time and space, groundwater becomes vulnerable to hazardous phenomena of different origin, natural or anthropogenic, that can produce disturbances in some water systems or default situations. Parametric models can be used to model the groundwater vulnerability and with the help of Geographical Information System (GIS) we can make the results of a complicated parametric model more clearly through visual representation. To achieve the above objective, the empirical model known as “DRASTIC” developed in USA by the Environmental Protection Agency (EPA) [1] as a way to produce a relative-risk scale of potential groundwater vulnerability to pollution that could be applied to a large area was adopted and tested with GIS to identify areas from Dobrogea Region (Romania) where the groundwater is more or less susceptible to pollution.

Nutritional Management in Child Diarrhea: An Evaluation of Awareness in General Population from Dobrogea Region

Abstract Diet has a major role in the treatment of acute diarrhea in children, along with a minimal drug therapy, but not necessarily using antimicrobials. Children can successfully pas a diarrheal episode with diet and symptomatic treatment. It is important to know how to properly choose foods to introduce in ill children diet. There is a lack of statistical data in our region regarding dietary treatment in child diarrhea. This study was realized by completing a questionnaire regrading nutritional management in children with diarrhea. 110 persons from Dobrogea region completed this questionnaire. We analyzes demographic and clinical issues, people preferences in choosing different foods appropriate to this pathology and minimal knowledge about medication. Our results evidenced that general population knowledges regarding nutritional management of acute diarrheal disease in children and infants are appreciable. Foods like rice, toast, applesauce/baked apple, mint/figs/bilberry leaves teas, vegetables soup, bananas were found among people preferences, proving appropriate information. Antimicrobial drugs misusage is not reported, 83 out of 110 people avoiding them.

Assessing the history-based predictability of regional monthly precipitation data using statistical and fuzzy methods

This paper points out two procedures for verifying the statistical independence between the historical and actual data series. They are based respectively on the computation of an empirical distance correlation coefficient, and the use of Hamming distance between binary encoded phase signals corresponding to Log-Gabor filtered time-series. Both procedures are applied to the monthly precipitation series recorded during 480 successive months at 49 meteorological stations in Dobrogea region (Romania) and on 4 and 5-valued fuzzified versions of the initial data represented using linguistic labels. The results show that the crisp data and their fuzzified versions cannot support the hypothesis of history-based predictability from their history. Hence, the two statistical independence tests are robust with respect to the k-means fuzzification of data and cross-validate each other, being applicable to any long-term analysis of precipitation series, to any other signals in general, and to their fuzzified versions, as well.

Influence of drip irrigation on peach tree growth in the chernozem of Dobrogea, Romania

In arid and semi-arid regions, irrigation should increase water use efficiency and decrease the impact on the environment, specifically in the context of global change. The split-plot experiment described here is bi-factorial: 1) with irrigation strategy having three graduations, and 2) two peach cultivars, namely ‘Southland’ and ‘Cardinal’, three years old. The irrigation regime consists of a fully irrigated treatment (T1, non-stressed) according to the irrigation needs (100% of ETc = ETo×Kc; Penman-Monteith method), a deficit irrigation treatment (T2) irrigated with half the amount of water in T1 (50% of ETc), and a control, non-irrigated treatment (T3). These plots comprised three adjacent fruit tree rows, with the central row containing five trees for measurements and observations. Soil water potential was measured with Watermark resistance blocks installed at four depths: 20, 40, 60 and 80 cm at a 1-m distance from the tree trunk, with two replicates for each tree. The paper describes peach growth in a chernozem of Dobrogea region, Romania. The study was carried out during three years (2010-2012). Irrigation application induced a significant increase in annual shoots in T1 versus the other two treatments, especially in ‘Southland’, under the specific soil and climate conditions of the region. The anticipated shoots and tree volumes were also different, depending on the irrigation amount.

Considerations on Water Supply Pumping Station Operation in the Context of Sustainable Development

Water and energy are among the most valuable resources worldwide, therefore specialists have to focus on technical means that enable better use thereof, also with respect to safety and efficiency. The study presents the operation efficiency improvement of a newly modernised water supply pumping station in Galesu irrigation system in the Dobrogea region, Romania. The technical measures led to a decrease of electrical power requirements by about 30%. A thorough study on the hydraulic shock pointed out the best protection solution provided with low-cost devices. A numerical simulation, conducted by the use of a noncommercial software, allowed to conduct a comparative study of the pressure field in different protection scenarios. The simulation showed no dangerous high-pressure values, but it revealed the occurrence of cavitation during hydraulic shock when the ducts have no protection devices. Simple protection solutions were compared, such as a two-stage closure of the check valve on the discharge duct and one or two air valves mounted in the most vulnerable cross sections of the discharge duct. The best protection was provided by a combination of these simple means.

Modern Concepts for Constructive Solutions in Dobrogea

Abstract In the summary published at the international conference WATER 2018, entitled “Modern concepts for constructive solutions in Dobrogea” [11], the authors briefly referred to the theoretical considerations and the case study on the concept of a “passive house” in the Dobrogea region - Romania, Constanta county, more precisely in the Mangalia area. In this article we will present this subject in great detail.

Conservation priorities for terrestrial mammals in Dobrogea Region, Romania.

Based on species occurrence records of museum collections, published literature, and unpublished records shared by mammalian experts, we compiled a distribution database for 59 terrestrial mammals populating the extensively protected Dobrogea Region of Romania. The spatial patterns of mammal distribution and diversity was evaluated and systematic conservation planning applied to identify priority areas for their conservation. The spatial analyses revealed that intensive sampling was not directly correlated to mammal diversity but rather to accessibility for inventory. The spatial prioritisation analysis indicated a relatively aggregated pattern of areas with a high or low conservation value with virtually no connecting corridors between them. The significant overlap between Natura 2000 sites and national protected areas induced an over-optimistic vision of the effectiveness and representativeness of existing Natura 2000 network for species found in Annexes II and IV of the Habitats Directive. These results represent a key step in identifying core areas for the protection of mammal diversity and dispersal corridors for improved connectivity, and to guide future conservation efforts in increasing the effectiveness of the existing protected areas in the context of environmental changes.

Evaluation of Droughts and Fires in the Dobrogea Region, Using Modis Satellite Data

Abstract Drought is one of the most significant extreme event facing the world, affecting the society and the environment. Located in SE Romania, Dobrogea Region is characterized by a temperate climate with strong continental influences, being affected by drought episodes which cause significant damages and economic costs over extensive agricultural areas. Risk reduction, continuous vegetation monitoring, and management implementation are facilitated by complementary use of vegetation indices and biophysical parameters derived from satellite products (gridded data) within-situ data (point data). The paper focuses on:i) evaluating the extent and intensity of drought in Dobrogea, Romania, based on Normalized Difference Drought Index (NDDI) and Fraction of Absorbed Photosynthetically Active Radiation (FAPAR); ii) fires analysis, based on the Thermal Anomalies/Fire locations product (MCD14DL); iii)the correlation between the fires with the NDDI; iv) and the correlation between fires with the Land Surface Temperature (LST) product. The vegetation indices, biophysical parameters and fires are computed from Moderate Resolution Imaging Spectroradiometer (MODIS) daily and eight days’ synthesis products, during 22th of March - 29th of August 2000-2015. The results highlight the areas most affected by drought (moderate, severe and extreme) and fires in the Dobrogea.

Researches Regarding New and Improved Technologies for Sunflower and Sorghum Crops in the Context of Climate Changes in Dobrogea Region

Abstract At Sport Agra in Amzacea, in the last few years there have been experimented new sunflower and sorghum crop technologies designed to face the current climate changes. These technologies for the intended crops include the following elements: changing the sowing epoch with one month before the usual period recommended by classical technologies; application of herbicides in order to control both weeds and Orobanche cumana Wallr. parasite in plots cultivated with various hybrids from Syngenta and Limagrain companies; application of last generation fungicides during the vegetation period, which will reduce the attack of the main crop pathogens; screening of hybrids with good behavior towards the main pest agent of area - Orobanche cumana parasite, which cause important yield losses in the south east past of Romania. There were tested 8 hybrids from Syngenta Company, 6 hybrids from Limagrain and 4 hybrids from NARDI Fundulea. The yields obtained for most of the hybrids were over 4 t/ha. For sorghum crop, there were performed various experiments such as: changing the sowing period - beginning of April in order to benefit from the soil’s humidity at 4-5 cm depth boosting the germination process; choosing early hybrids in order to avoid the drought season which starts in June; applying adequate crop protection treatments, with pre-emergent and postemergent herbicides and last generation insecticides. The obtained production from sorghum crop were over 10 t/ha for most of the varieties tested.

Autumn Passage of Soaring Birds over Dobrogea (Romania): A Migration Corridor in Southeast Europe

The Dobrogea region in southeastern Romania, which is part of the Eurasian-East African Flyway, is listed as one of the important migration corridors for soaring birds on the western coast of the Black Sea. However, our knowledge regarding migration intensity, phenology and geographical patterns of soaring birds over the area is poor. To determine the migration intensity and phenology of soaring birds, we recorded the autumn migration in the Măcin Mountains (northern Dobrogea) from mid-August to the end of October between 2002–2007. To describe the geographical patterns of migration at a regional scale, we recorded migration intensity in the second half of September in 2010 and 2011, simultaneously from 15 and 13 counting points, respectively, covering the entire region of Dobrogea. In the Măcin Mountains we recorded a mean number (±SD) of 11,297 ± 2333.5 (CV = 20.7%) migrating raptors per year, and of 21,367 ± 10,949.3 (51.2%) and 455.6 ± 43.6 (9.6%) migrating White Storks Ciconia ciconia and Black Storks Ciconia nigra, respectively. Migration phenology parameters varied across raptor and non-raptor species. Migration occurred over a broad front, covering all of Dobrogea. However, migration intensity was more pronounced in the western, central and eastern parts of the region, and was less intensive in the northern central areas. Overall, we recorded 30 migrating raptor species and three non-raptor species. The most abundant raptors were Common Buzzard Buteo buteo, European Honey Buzzard Pernis apivorus, Lesser Spotted Eagle Clanga pomarina, Eurasian Sparrowhawk Accipiter nisus and Western Marsh Harrier Circus aeruginosus. The three non-raptor species were White Stork, Black Stork and Great White Pelican Pelecanus onocrotalus. Our study provides the first general overview of the autumn passage of soaring birds over Dobrogea, highlighting the importance of this area as part of a global migration network.