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In addition to the naturopathic medicines based on the antiseptic, anti-inflammatory, anticancer, or antioxidant properties of plant extracts that have been capitalized upon through the pharmaceutical industry, the increasing interest of the food industry in this area requires potent new materials capable of supporting this market. This study aimed to evaluate the in vitro amino acid contents and antioxidant activities of ethanolic extracts from sixteen plants. Our results show high accumulated amino acid contents, mainly of proline, glutamic, and aspartic acid. The most consistent values of essential amino acids were isolated from T. officinale, U. dioica, C. majus, A. annua, and M. spicata. The results of the 2,2-diphenyl-1-pycrylhydrazyl (DPPH) radical scavenging assay indicate that R. officinalis was the most potent antioxidant, followed by four other extracts (in decreasing order): T. serpyllum, C. monogyna, S. officinalis, and M. koenigii. The network and principal component analyses found four natural groupings between samples based on DPPH free radical scavenging activity content. Each plant extracts’ antioxidant action was discussed based on similar results found in the literature, and a lower capacity was observed for most species. An overall ranking of the analyzed plant species can be accomplished due to the range of experimental methods. The literature review revealed that these natural antioxidants represent the best side-effect-free alternatives to synthetic additives, especially in the food processing industry.

This study aims to develop an HPLC analytical method, for separation, identification and quantification of related substances and degradation products, in veterinary finished product with two active substances Enrofloxacin (ENR) and Bromhexine hydrochloride (BRM). Analytical method used an Agilent Eclipse Plus C18 column (150 mm length x 4,6 mm I.D., 5 µm particle size) and a mobile phase consisted in a mixture of 2.5% phosphoric acid buffered at pH-2.3 with trimethylamine and acetonitrile in a gradient mode from 85% FMA to 55% FMA in 14,2 minutes, isocratic mode for 1 more minute and re-equilibration, total chromatographic time being 21 minutes. The method was developed in order to assure the separation of impurities specific with ENR and BRM. Specificity in relation with degradation products revealed up to 20 impurities for ENR and 5 impurities related with BRM. The spectra of impurities were chosen among the compounds found in forced degradation studies. Method validation was performed according to VICH GL 2 – Validation of analytical procedures and included selectivity/specificity, linearity, accuracy, precision, LOQ, LOD, robustness, system suitability. Under these conditions linearity was between 0.015–0.06 mg/mL for ENR and 0.001125–0.005625 mg/mL for BRM. Limit of quantification for ENR was 0.00292 mg/ml and 0.001103 mg/ml for BRM. These limits assured method performance because they are under the reporting threshold from VICH GL11 Impurities in new veterinary medicinal products which is 0.3%. Recovery was calculated on three concentrations for every compound and were 102.99% for ENR and 102.91% for BRM. In terms of intermediate precision, a relative maximum deviation of 2.5% was obtained for area and retention of the two compounds by using two analysts in two different days of application. This method used common and cheaper reagents and can separate and quantify, in a short time, all these compounds and is suitable to be used in quality control of the product.

The European mitigation strategy for combatting climate change requires up-to-date knowledge about the environmental effects of greenhouse gas (GHG) emissions at the national scale. As a strong response to the consequences of climate change, the European Union has imposed on the member states an obligation to achieve the goals set out in the climate and energy package, which were aimed at reducing emissions. Therefore, underlying the trends of GHG emissions is essential when establishing climate change mitigation measures. This study identify the structure and dynamics of the GHG emissions of the six sectors of the European economies, over 27 years, and reveal the significance, direction, rate, and drivers of the observed trends using the method of modifying the absolute mean. The results indicate a decrease in the GHG emissions in the EU-28 by an average of 1% annually, which can be explained by a mixt factors, such as resize of the industry, improved energy efficiency, the growing share of renewables and less use of carbon fuels. Moreover, through the environmental policies adopted in the last decade, was observed that the GHG emissions level in 2017 had declined by approximately 25% in comparison with the reference (1990) and by approximately 17% by 2005. From the 28 EU countries (EU-28), Romania produced 4.2% of the total EU-28 GHG emissions in 1999, which decreased to 2.7% in 2005 and reaching 2.3% in 2017. Romania contributed to 14% of the average annual decrease in emissions. This evidence highlights the additional support for further reduction beyond that required for climate change mitigation.

In recent years, phytofunctionalized AgNPs have attracted great interest due to their remarkable biological activities. In the present study, AgNPs were synthesized using Abies alba and Pinus sylvestris bark extracts. The chemical profile of these bark extracts was analyzed by LC-HRMS/MS. As a first step, the synthesis parameters (pH, AgNO3 concentration, ratio of bark extract and AgNO3, temperature, and reaction time) were optimized. The synthesized AgNPs were characterized by ATR-FTIR spectroscopy, DLS, SEM, EDX, and TEM. Their antioxidant, cytotoxic, and antibacterial properties were evaluated by the DPPH, ABTS, MTT, and broth microdilution assays, respectively. Abies alba and Pinus sylvestris bark extract-derived AgNPs were well-dispersed, spherical, small (average particle size of 9.92 and 24.49 nm, respectively), stable (zeta potential values of −10.9 and −10.8 mV, respectively), and cytotoxic to A-375 human malignant melanoma cells (IC50 = 2.40 ± 0.21 and 6.02 ± 0.61 μg/mL, respectively). The phytosynthesized AgNPs also showed antioxidant and antibacterial effects.

This study aimed to analyze Romanian (RO) involvement in the LULUCF sector by considering the Intergovernmental Panel on Climate Change (IPCC) good practice guidance (GPG). Trends were assessed using the Mann-Kendall (MK) test for trend estimation to determine the total greenhouse gas (GHG) (GHGCO₂-eq.) emissions/ removals. The results emphasized the increasing average annual levels of emissions/removals in both the EU-28 and RO when the subperiods from 1990-2005 and 2005-2017 were analyzed. Kendall’s analysis of GHG removal showed a positive trend in Romanian GHG removals, and no trend was observed for the EU-28. In comparison, the emissions indicated an increasing trend for RO and a decreasing trend for the EU-28. The GHGCO₂-eq. generated by the LULUCF sector decreased to an average annual rate of 0.5% per year in the EU-28. In Romania, these emissions increased by approximately 0.2% per year on average. Between 1990 and 2017, the CO2 total absorption increased to 0.9% per year. The methane absorption also increased by 11.7% per year, and no significant increasing trend was observed for methane. The dynamics of GHGCO₂-eq. emissions/removals in RO and LULUCF sectors showed that settlement had decreased in wetlands, and settlement of other land areas had increased. Assessing GHG gas emissions is essential for allowing each sector to promote specific strategies, policies and action plans. This will improve the national-level monitoring of the LULUCF sector and make this information more accessible to decision makers by raising awareness of the Romanian position within the EU-28

Mining activities, in combination with accelerated urbanization growth and climate change, constitutes a major challenge for creating a sustainable development. Thus, the monitoring and assessment of mining effect is mandatory in understanding the impact on the primary physico-chemical characteristics of an environment. In this context, the paper presents the evolution of micro- and macro- nutrients in water, soil and sediment from two industrial areas from Romania (Copșa Mică industrial platform and Baia Sprie mining zone), in order to assess the impact of pollutants on ecosystems. Physico-chemical (pH, NH4+, NO3-, NO2-, TN, TP), base cations (Ca, Mg, Na and K) and micronutrients (Fe, Mn and Zn) have been analyzed in order to evaluate the quality of the environment. For some of the analyzed soils, the concentration of Zn, Mn and Fe exceeded the maximum permissible limits (MPL) imposed by the Romanian legislation, falling within the limit for Alert Thresholds for less sensitive soils. The correlation analysis on water quality parameters revealed that all parameters are more or less correlated with each other Person’s Correlation matrix. Overall, our results demonstrated that the knowledge of the physico-chemical regime of an environment is of great value in the determination of its productivity, usefulness and other characteristics which can facilitate further vegetation restoration and reconstruction and a sustainable development of the ecological environment in a polluted area.

Ageing of wines on lees (autolysis) involves keeping wines in contact with dead yeast cells for several months/years to intensify the transfer of compounds between yeast cells and wine. During yeast autolysis, release of different compounds has been shown to have a positive influence on organoleptic characteristics of wine as these compounds, including lipids, mannoproteins, peptides, proteins, amino acids, and glucans, are breakdown products of yeasts and can impact on volatile profile of wine. The aim of this study was to evaluate the quality of white and rosé wines aged in contact with lees for 2 months, using 12 commercial maturation products. The studied wines were produced in Iasi vineyard, vintage 2020, from Sauvignon blanc and Busuioacă de Bohotin grapes variety. Thus, 26 samples were obtained (V1 SB-V13 SB; V1 BB – V13 BB). The effect of ageing on lees was assessed by analysing some main aroma compounds, performing an organoleptic analysis and quantifying color changes (CIEL ab parameters). The first impression that the consumer receives from wine is color and to some extent it can influence the taste. In terms of color parameters, an increase in color intensity was evident for all samples after the lees ageing period. Sensorial analysis coupled with statistical analysis tests showed a definite correlation between the maturation products used and their composition vs. certain sensorial indices. The treated wines boasted a smoother sensorial profile, with enhancement of mouth feel and persistence (V2, 3, 11 SB and V2, 3, 11 BB).

The present study was conducted to quantify the daily intake and target hazard quotient of four essential elements, namely, chromium, cobalt, nickel, and copper, and four toxic trace elements, mercury, cadmium, lead, and arsenic. Thirty food items were assigned to five food categories (seeds, leaves, powders, beans, and fruits) and analyzed using inductively coupled plasma-mass spectrometry. Factor analysis after principal component extraction revealed common metal patterns in all foodstuffs, and using hierarchical cluster analysis, an association map was created to illustrate their similarity. The results indicate that the internationally recommended dietary allowance was exceeded for Cu and Cr in 27 and 29 foodstuffs, respectively. According to the tolerable upper level for Ni and Cu, everyday consumption of these elements through repeated consumption of seeds (fennel, opium poppy, and cannabis) and fruits (almond) can have adverse health effects. Moreover, a robust correlation between Cu and As (p < 0.001) was established when all samples were analyzed. Principal component analysis (PCA) demonstrated an association between Pb, As, Co, and Ni in one group and Cr, Cu, Hg, and Cd in a second group, comprising 56.85% of the total variance. For all elements investigated, the cancer risk index was within safe limits, highlighting that lifetime consumption does not increase the risk of carcinogens.

The aim is to introduce and characterize a new experimental demonstrative model contributing to the increase of measurement accuracy, in terms of minimum detectable activity (MDA) and background reduction, for the analysis of samples having low concentrations in tritium and radiocarbon on Quantulus 1220. The clue is related to the qualitative and quantitative differences between tritium and carbon-14 inventories of the pulp used to manufacture the cups involved in noncatalytic combustion of samples by flame oxidation method. The quality of the experimental results depends on the temporal origin of the wood from which the pulp/cellulose was extracted/purified, the specific inventory contributing to the threshold level of the MDA for the beta-emitting radionuclide to be investigated. Finally, the aim is to create and to use such a 100% old cellulose combustion cups for determining low concentrations of these radionuclides. It may be obtained by an adapted technology following the literature data and may be recommended for routine analyses of environmental samples coming from areas with no nuclear or minor nuclear influences, and also for low-level biological samples. This first attempt resulted in improvement of measurement performances up to 400% for carbon-14 and by approximately 50% for tritium.

The Holocene fluvial history of rivers draining the Romanian Carpathians has been assessed using a database resulting from the authors’ own field research at more than 50 sites comprising natural exposures (riverbanks), anthropogenic exposures (gravel pits) and manual boreholes carried out in floodplains, as well as on the analysis of over 30 published sources. Thus, 196 dated fluvial units were obtained, of which, subsequent to filtering, 142 units were retained for application of Cumulative Probability Functions (CPFs). To this database we added 274 radiocarbon-dated lacustrine sedimentary units originating in small lakes and bogs linked to the fluvial network of the study area. The resulting data bases were classified, processed and analysed under the methodological framework of meta-analysis in order to reconstruct the phases of geomorphic activity of rivers during major flood events and periods of low hydroclimatic intensity throughout the Holocene, and to understand the river response in terms of dominant fluvial processes. Based on the analysis of probability frequency, 17 major flooding episodes were identified, of which 12 (mostly from the last 4500 years) coincide with wet phases determined for lacustrine sedimentary units from the study area. At regional scale, of the 17 centennial intervals with flood events recorded in fluvial archives from Romania in the last 10 ka, 15 intervals are synchronous with at least one area from Central or Eastern Europe, leading to the conclusion that the climatic factor manifested dominantly in SE Europe, as well. At local scale, the orographic barrier of the Carpathians interfering with the dominant circulation of western air masses has modified the magnitude and timing of flood events, resulting in increased rates of hydroclimatic and geomorphic processes in western rivers compared to rivers east of the Carpathian range. Other controls which have local influence on the evolution of hydroclimatic processes (i.e. vegetation changes and human impact) determined an increase in the susceptibility of areas located between 700 and 1000 m asl throughout Romania and contributed to the acceleration of fluvial systems dynamics post ca. 4500 cal BP.

From 1997 to the present, a sustained project in the Maramureș region in Romania was completed with the construction of a 781-year oak tree-ring chronology. A total of 395 samples from living trees and 429 from archaeological wood were analysed with dendrochronological methods. The study aimed to provide the scientific community with a new oak chronology that could be applied in dendroarchaeology, dendroclimatology and dendroecology studies and also for interpreting past socio-economic events. Furthermore, we studied the number of sapwood rings and the growth pattern for different time periods. The chronology covered the continuous period of A.D. 1236‒2016. From the 824 samples collected, we separated 271 tree-ring series into a new chronology (A.D. 1406–2016), which fulfilled all the criteria necessary to reconstruct past climate and environmental changes. The resulting new tree-ring chronology indicated robust signal series intercorrelation (r = 0.55) and an average mean sensitivity of 0.21. Based on an analysis of the sapwood, we recommend estimating a number between 8 and 32 rings to the date of final ring for 95% confidence range of mean on the for felling in the Maramureș region. Additionally, we observed that the number of sapwood rings was not correlated with altitude or oak tree species.

Modern society faced significant challenges in the last decades as a result of environmental pollution and climate change. The current study's objective was to establish a pattern for assimilating HM in normally and declined Quercus robur L. trees. Also, was identify the present state and historical changes in heavy metal elemental composition using different approaches: i) twenty matrices including water, soil, sediments, mushrooms, acorn, leaves, branches, bark and wood; ii) tree-rings elemental time-series trends. Our research of elemental distribution in pedunculate oak earlywood tree-rings brings new viewpoints for investigating chronic decline and dieback using (LA-ICP-MS), (ICP-MS) and (AAS) technics. Impressive amounts of heavy metals in the background environment, especially in water and mushrooms indicate high environmental risk for human health. The Levene's t-test shows significant differences (p-valuet-test shows significant differences (p-valueAcknowledgementsThis work was supported by the Romanian National Authority for Scientific Research and Innovation, Contract No. 12N/2019 (PN 19070502 "Evaluation by transdisciplinary techniques of the oak trees decline affected by actual environmental changes in the extra-Carpathian area – adaptation, mitigation and risks") and Contract No. 9N/2019 (PN 19110303" Advanced techniques for identifying sources of contamination and biochemical reactions in aquatic ecosystems" and PN19110302 "Research on the variation trends specific to stable isotopes in different tree species: deepening the fractionation mechanisms and the chemical processes interconnected on the soil-water-plant chain"), partially by CRESFORLIFE ID_40_380 - Subsidiary contract S16/2020.

Silver nanoparticles synthesized using plant extracts as reducing and capping agents showed various biological activities. In the present study, colloidal silver nanoparticle solutions were produced from the aqueous extracts of Picea abies and Pinus nigra bark. The phenolic profile of bark extracts was analyzed by liquid chromatography coupled to mass spectrometry. The synthesis of silver nanoparticles was monitored using UV-Vis spectroscopy by measuring the Surface Plasmon Resonance band. Silver nanoparticles were characterized by attenuated total reflection Fourier transform infrared spectroscopy, Raman spectroscopy, dynamic light scattering, scanning electron microscopy, energy dispersive X-ray and transmission electron microscopy analyses. The antimicrobial and cytogenotoxic effects of silver nanoparticles were evaluated by disk diffusion and Allium cepa assays, respectively. Picea abies and Pinus nigra bark extract derived silver nanoparticles were spherical (mean hydrodynamic diameters of 78.48 and 77.66 nm, respectively) and well dispersed, having a narrow particle size distribution (polydispersity index values of 0.334 and 0.224, respectively) and good stability (zeta potential values of −10.8 and −14.6 mV, respectively). Silver nanoparticles showed stronger antibacterial, antifungal, and antimitotic effects than the bark extracts used for their synthesis. Silver nanoparticles obtained in the present study are promising candidates for the development of novel formulations with various therapeutic applications.

Annually resolved tree rings enable us to distinguish past pollution and climate change effects on chronic tree decline, which affects significant areas around the world. The aim of the current study was to establish a pattern for the assimilation of heavy metals in regular and declining Quercus robur L. trees. Using laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS), ICP-MS, and atomic absorption spectroscopy (AAS), the present and historical changes in element levels were investigated. Twenty different environmental species, including water, soil, sediments, mushrooms, acorn, leaves, branches, bark, and wood, were analyzed. Time profiles of elements in earlywood tree rings were investigated. We demonstrated higher HM contamination in the present background with increasing Pb and Cd levels. The presence of Li and Sr in groundwater was reported for the first time. We found significant differences (p

This study focuses on the climate growth drivers of Quercus robur L. (pedunculate oak) and Q. robur subsp. pedunculiflora K. Koch. (greyish oak), occurring in the biodiversity of three sites in southern Romania. We determined the degree of tolerance of the greyish oak, between the tardive and praecox varieties, to environmental stress, between 1951 and 2016. Total tree ring-width (RW), and earlywood (EW) and latewood (LW) measurements were subject of periodical and monthly climate-growth analysis. Our results revealed a moderate relationship between climate and tree-growth. A significant and positive relationship was observed between RW and previous growing season precipitation. Mean and minimum temperatures affected both positive and negative tree-rings during the growing season. We also observed that winter and spring represent key seasons for differentiating tardive from praecox varieties, affecting the intra-annual variability of ring-width, and EW and LW parameters. The correlation between the tree-ring measurements and daily climate data shows a clear offset of the starting growth between greyish oak varieties. A weak influence of stressors on tree-growth at the sites was observed through pointer year and resilience components analysis.

The concentrations of twelve heavy metals and trace elements (Cr, Mn, Co, Ni, Cu, As, Cd, Pb, Hg, Zn, Fe, and Al) in bed sediment and river freshwater that received sewage discharge, industrial wastewater inputs and mining residue were discussed. Spatial distribution, intra-annual trends and diffuse flux in 2019 in the middle and lower reaches of Olt River Basin (ORB) were investigated using inductively coupled mass spectrometry (ICP-MS) and atomic absorption spectroscopy (AAS). We applied correlation and principal component analysis (PCA) to quantify metal distribution relationship within environmental factors (pH, air temperature) and organic matter existing in the ORB. Moreover, the 87Sr/86Sr and 206Pb/207Pb isotope ratios analysis was employed to conclude the possible origin of the contamination. PCA analysis categorized metal presence in the four-component model, which explains 91% (May), 92% (July) and 93% (September) of the variance and indicates the potential origins of pollutants. The HCA and correlation analysis emphasized the relationship between trace elements, heavy metals in water and sediments and physicochemical characteristics of water. It was observed a high discrepancy in metal distribution between riverbed sediments and water body. In September, correlation indices highlighted sparse positive relationship with trace elements in water and mainly negative correlation values with trace elements from sediments. The origin of pollutants in sediments and water appear to be both natural and human-related activities. In all seasons increased the total exchangeable concentration of Ni, Cu and Zn in the sediments downstream sewage treatment plants and upstream of dams. The consideration of environmental factors and physicochemical characteristics of water is required to develop strategies for pollution management, assessment and mitigation in the actual condition of climate change. This study evaluated the heavy metals pollution in the Olt River Basin over three periods in 2019 under human-induced changes.

This paper focused on the analysis of the interpretation potential given by fluvial archives, in order to decipher the Mid- to Late Holocene sedimentary history. The database discussed here refers to 65 dated ages (mostly radiocarbon), mappings of the most representative floodplain reaches of Suceava, Moldova and Siret rivers, and 23 outcrops analysed in floodplain deposits (river banks or gravel pits). The study results concentrated on (a) describing the regional features of Eastern Carpathian floodplains, (b) the floodplain morphology and its correlation with the structure of fluvial deposits and (c) identifying the paleoevents of fluvial activity on a centennial timescale. In this way, we were able to identify a general pattern of the dynamic geomorphology history for the rivers situated eastward of the Carpathians, which resulted from combining the Mid- to Late Holocene sedimentation phases, the avulsion and lateral migration processes that occurred during high fluvial activity intervals and the morphological adjustment of the rivers channels, from braiding to wandering and sinuously–meandering. The chronological overlay of the events revealed that the time intervals with the most extensive fluvial processes on the rivers draining the Eastern Carpathians occurred (in years before present) during 6200, 5300, 4100–4080, 3600, 2300–2200 (Iron Age), 1300 (Migrations Period), 950–970 (Medieval Climate Anomaly), 750–520 BP (Little Ice Age)and that these intervals generally overlap the high precipitation palaeoclimatic episodes documented in Romania. The fluvial activity of the rivers during the Mid- to Late Holocene has been compared as well with several records of paleo–climates variability over the geographical area of Romania. The result showed that many flooding episodes were coincident with the wet and cold intervals which were also identified in the variation of the other proxydata, especially after 4.7 kcal BP.

The main objective of this paper is to describe the late Holocene behaviour of rivers using an interdisciplinary approach combining fluvial geomorphology and subfossil trunk dendrochronology. The subfossil wood material collected along the rivers was investigated for dendrometric and dendrochronologic parameters. The research methods in these fields helped us to understand the effect of the fluvial environment on riparian trees and their records and helped in reconstructing the riparian palaeoenvironment. The study area consists of two rivers with different typologies but comparable sizes: the Moldova River, which features a braided to wandering channel in its lower reach, and the Siret River, which features a sinuous-meandering channel. Along the 100-km-long floodplain of the former and the 144-km-long floodplain of the latter, we found and sampled 77 subfossil trunks, of which 26 were subjected to 14 C dating. The resulting data consist of floodplain facies mapping data, electric resistivity measurements, absolute dates, and dendrometric and dendrochronologic data. The results indicate that during a 100-year period, the two rivers were sensitive to climate change and anthropogenic effects, particularly a narrowing of the active channel by 76% in the braided channel and 38% in the sinuous-meandering channel. During the past 3300–3000 YBP, the Moldova River maintained its braided style, whereas the sinuous-meandering style has been characteristic of the Siret River for the previous 6800–4600 YBP. The two distinct fluvial environments are recorded in the dendrometric structure of the trunks buried in the channel-fill sediments. The braided fluvial environment was more effective in uprooting riparian trees and incorporating them in the floodplain deposits, whereas the sinuous-meandering style of stream effectively buried tree trunks in lateral accretion lobes. Absolute and dendrochronologic dating allowed for the reconstruction of timelines of the felling of the trees and estimates of the magnitude of the responsible hydrological event. The flood events on the Siret River with a recurrence interval of 200 years ( Q max ~ 2500–2800 m 3 /s) were those most effective in destroying riparian forests, and the events on the Moldova floods with a 100-year recurrence interval ( Q max ~ 1200–1400 m 3 /s) were the most effective. Dendrochronology allowed for identification of wet phases (i.e., 3500–2900 YBP, 2200–2075 YBP, and 1000–800 YBP) and dry phases (e.g., 3200–3150 or 2775–2700 YBP, 1400 YBP). Finally, we draw attention to the potential for creating a highly replicable dendrochronological series spanning at least 7000 YBP.

Dendrochronological research was conducted in Europe in several centers whereby oak trees, regardless of species, originating from various archaeological sites were studied. Thereby, several shronologies were assembled in Ireland, Germany and the UK, covering the past 7000 to 8000 years. The environment impacts on tree growth by generating higher / lower growth ratescompared to the multinannual average, thus indicating extreme years. The patterns of extreme years pertaining to individual sequences are subsequently synchronized by cross-dating.The study area consists of two rivers with different typologies but comparable in terms of size: river Moldova (braided to wandering channel in the lower reach) and river Siret (sinuosmeandering channel). Along the 100 km-long floodplain of the former and the 144 km-long floodplain of the latter we found and sampled 77 subfossil trunks from which 26 were subjectedto 14C dating

Tree-ring information and climate response data were applied to investigate the potential of the Carpathian Mountains to influence tree-growth patterns. Recent studies reveal the importance of constructing a dense spatial network of oak tree-ring chronologies in this area, which may be the key to linking the North Central European and East Mediterranean tree records. We establish sixteen oak ( Quercus robur L.) and sessile oak ( Quercus petraea (Matt.) Liebl.) site chronologies along a longitudinal gradient (from 22.47 to 26.58 E) in Northern Romania in an attempt to elucidate the impact of climate on oak growth. Even with differences generated by interspecific features, habitats and climatic regimes, a common macroclimatic marker for the NW and NE sites was established by comparing two groups of chronologies separated by the Carpathian chain. We found that precipitation in April (P4) and June (P6) were the primary climate factors that affected tree growth in the NW region. For the NE region, the temperature in January (T1) and March (T3) and precipitation in May (P5) were revealed to be the major limiting climatic factors. The spatial variability of the correlation coefficients indicates a decreasing trend in correlation intensity with precipitation from NW to NE, particularly during the current growing season (March–July). Oak trees from the NW and NE regions have adapted to different local climatic conditions and only respond uniformly to severe climate events (e.g., the 1904 drought). The higher occurrence of extreme years during the 20th century, particularly in the NE region, was in accordance with the rise of precipitation variability in the current growing season. The changes in the tree-growth pattern and climatic response of the chronologies of the studied sites in the NW and NE regions were linked to the local climates induced by the Carpathian Mountains.

Dendrochronological research in North-Central Europe and the East Mediterranean has produced networks of long regional oak (Quercus sp.) reference chronologies that have been instrumental in dating, provenancing, and paleoclimate research applications. However, until now these two important tree-ring networks have not been successfully linked. Oak forests and historical/archaeological sites in southeastern Europe provide the key for linking the North-Central European and East Mediterranean tree-ring networks, but previous dendrochronological research in this region has been largely absent. This article presents the initial results of a project, in which we have built oak tree-ring chronologies from forest sites and historical/archaeological sites along a north-south transect between Poland and northwestern Turkey, with the aim of linking the North-Central European and East Mediterranean tree-ring networks and creating a new pan-European oak data set for dendrochronological dating and paleoclimatic reconstruction. Correlation among tree-ring chronologies and the spatial distribution of their teleconnections are evaluated. The southeastern European chronologies provide a solid bridge between both major European dendrochronological networks. The results indicate that a dense network of chronologies is the key for bridging spatial and temporal gaps in tree-ring records. Dendrochronological sampling should be intensively continued in southeastern Europe because resources for building long oak chronologies in the region are rapidly disappearing.

Summary 1. Growth rates of European silver fi r( Abies alba Mill.) rapidly increased in the last century. At the same time, ring widths declined at the species southern distribution limits in the Mediterranean. Such diverse growth trends and responses have largely been attributed to regional climate conditions, but this was prior to considering the species’ post-glacial phylogeny. 2. A dendrochronological network composed of 1961 tree-ring width series (TRW) from 78 silver fir sites between 365 and 1400 m a.s.l. along the Carpathian Arc was compiled. Spatial differences in the species’ genetic diversity were investigated from genetic data of 69 silver fir populations in the region. Differences in growth variability and climate sensitivity were then related to post-glacial phylogeny and genetic diversity. 3. Significant differences in interannual and longer-term growth trends and climate responses across the Carpathian Arc were found to coincide with the geographical north–south separation of two post-glacial populations from effective refugia originating from the Apennine and Balkan peninsulas. Summer temperature was the main driver of growth in the western (Apennine) lineage, whereas ring widths in the Balkan population from the east were predominantly controlled by summer drought. Fir specimens that originated from the Balkan lineage exhibited higher genetic diversity and more regular growth dynamics and also appeared to be less sensitive to air pollution during the 1970s. 4. Synthesis. Although the phylogeny of forest trees has largely been neglected in most dendroecological studies, results here indicate the importance of different post-glacial histories for the growth sensitivity and adaptability to varying environmental factors. Decision-making under future climate warming scenarios (for building resilience through forest management) should therefore consider different phylogenetic origins.

Increase in temperature and decrease in precipitation pose a major future challenge for sustainable ecosystem management in Romania. To understand ecosystem response and the wider social consequences of environmental change, we constructed a 396-year long (1615-2010) drought sensitive tree-ring width chronology (TRW) of Pinus nigra var. banatica (Georg. et Ion.) growing on steep slopes and shallow organic soil. We established a statistical relationship between TRW and two meteorological parameters-monthly sum of precipitation (PP) and standardised precipitation index (SPI). PP and SPI correlate significantly with TRW (r = 0.54 and 0.58) and are stable in time. Rigorous statistical tests, which measure the accuracy and prediction ability of the model, were all significant. SPI was eventually reconstructed back to 1688, with extreme dry and wet years identified using the percentile method. By means of reconstruction, we identified two so far unknown extremely dry years in Romania--1725 and 1782. Those 2 years are almost as dry as 1946, which was known as the "year of great famine." Since no historical documents for these 2 years were available in local archives, we compared the results with those from neighbouring countries and discovered that both years were extremely dry in the wider region (Slovakia, Hungary, Anatolia, Syria, and Turkey). While the 1800-1900 period was relatively mild, with only two moderately extreme years as far as weather is concerned, the 1900-2009 period was highly salient owing to the very high number of wet and dry extremes--five extremely wet and three extremely dry events (one of them in 1946) were identified.

The first 600 years long tree-ring width chronology for Southern Carpathians was established based on living and subfossil Swiss stone pine (Pinus cembra L.) samples from an upper timberline forest located in Retezat Mts. (Romania). Study area is located in Retezat Mts. where we can find the most expanded population of stone pine from Southern Carpathians. The timberline is represented by a mixed stands of Norway spruce and stone pine which is replace by mountain pine toward higher altitude. We have compiled the longest tree rings chronology from Carpathians using samples from dead and living trees of stone pine (Pinus cembra).