The consideration of a theoretical probability distribution regarding the annual cumulative discharge will provide a significant opportunity to characterize the intensity of the hydrological drought. ...However, the matching between the observed probabilities and the adopted theoretical probability distribution can not be identical. Hence, in this work this matching is achieved by using a fuzzy regression based methodology and the attributes of the log-normal distribution. Finally, an ascending procedure to classify the intensity of hydrological drought is proposed and it is applied in case of the Evros River.
In the Aegean back‐arc domain, some 30–35 Ma ago, an increase of the rate of slab retreat led to the initiation of post‐orogenic extension, largely accommodated by large‐scale structures such as the ...North Cycladic Detachment System (NCDS). Although this extension is still active nowadays, an E–W compressional regime developed in the Late Miocene with the propagation of the North Anatolian Fault. On Mykonos island (Cyclades), the NE–SW back‐arc extension is particularly well expressed with the Livada and Mykonos detachments that belong to the NCDS and that are associated with NW–SE barite veins emplaced during the synkinematic cooling of the Mykonos intrusion. This study shows that the formation of the mineralization occurred when the pluton crossed the ductile‐to‐brittle transition during its exhumation below the NCDS at ~11–10 Ma. In addition, the kinematics of mineralized structures evolved with time: (1) most of the displacement was accommodated by the top‐to‐the‐NE Livada and Mykonos detachments accompanied by the formation of mineralized normal faults that were (2) reworked in a strike‐slip regime with an E–W direction of shortening and a persistent NE–SW stretching and (3) a late post‐mineralization E–W compressional stage with a minor reworking of shallow‐dipping faults (locally including the detachments themselves). We interpret this increase of the E–W shortening component recorded during the mineral deposition as a consequence of the initiation of the westward motion of Anatolia from 10 Ma, thus 4 Ma before the propagation of the North Anatolian Fault in the Dardanelles Strait and the localization of the strain on the Aegean Sea margins.
Key Points
Evolution from extension to compression during the late Miocene in the AegeanInteractions between detachments, intrusion and mineralization on MykonosDating the first westward motion of Anatolia at ~11‐10 Ma
We examined six groups of taxa-woody plants, aquatic and terrestrial herpetofauna, small terrestrial birds, orchids, and Orthoptera-to determine their efficiency as biodiversity indicators in the ...Dadia Reserve in northern Greece. We investigated the indicator value of each group by examining the degree of congruence of its species-richness pattern with that of the other groups and the efficiency of its complementary network in conserving the other groups and biodiversity. The two techniques differed in many respects in their outputs, but they both showed woody plants as the best biodiversity indicator. There was in general low congruence in the species richness patterns across the different groups. Significant relationships were found between woody plants and birds, Orthoptera and terrestrial herpetofauna, and birds and aquatic herpetofauna. None of the optimal complementary networks of the groups we examined protected all species of the other groups. Nevertheless, the complementary network of woody plants adequately conserved all groups except orchids. We conclude that the principle of complementarity must be integrated into the methodology of evaluating an indicator. In an applied context, our results provide a scientific background on which to base a biomonitoring program for the Dadia Reserve. In a wider scope, if the group of woody plants prove an adequate biodiversity indicator for other Mediterranean areas as well, this will be important because it will facilitate conservation-related decisions for the entire Mediterranean region.
The discovery of the racer goby
Babka gymnotrachelus
in the transboundary Evros river basin, collected on September 10th 2018 at two locations very close to the Greek-Bulgarian and Greek-Turkish ...borderlines, is reported. This is a new addition to the non-native ichthyofauna of Greece and the Aegean Sea drainages, and it is the second non-native Ponto-Caspian goby to enter this river. Boat-based electrofishing sampling, following the EU Water Framework Directive monitoring program, provides first evidence of what is presumed to be a recently established population; most of the 13 collected specimens are juveniles and the species has not yet been located in the river's tributaries. Further study and international cooperation in monitoring and management of this and other alien species in the Evros are proposed.
La présence du gobie coureur
Babka gymnotrachelus
dans le bassin transfrontalier du fleuve Evros, prélevé le 10 septembre 2018 à deux endroits très proches des frontières gréco-bulgare et gréco-turque, est signalée. Il s'agit d'un nouvel ajout à la faune ichtyenne non indigène de la Grèce et aux bassins versants de la mer Égée, et c'est le deuxième gobie Ponto-Caspien non indigène à entrer dans cette rivière. L'échantillonnage de la pêche à l'électricité par bateau, conformément au programme de surveillance de la Directive-cadre sur l'eau de l'UE, fournit les premières preuves de ce qui est présumé être une population récemment établie ; la plupart des 13 spécimens prélevés sont des juvéniles et l'espèce n'a pas encore été trouvée dans les affluents de la rivière. Il est proposé de poursuivre l'étude, et la coopération internationale en matière de surveillance, et de gestion de cette espèce et d'autres espèces exotiques dans la région d'Evros.
The Mediterranean area is highly vulnerable to climate changes that combined with potential land use changes could influence its aquatic systems significantly. The Evros River is one of the most ...important surface water bodies in the Balkans with an ecologically significant delta that is protected by international legislation. The aim of this study is to analyze the impacts of climate and land use changes on Evros River water quality, for different climatic and socioeconomic scenarios. For this purpose, a hydrodynamic and advection-dispersion model was set up and calibrated, three IPCC climatic scenarios were applied, and the pollution loads of the catchment area were estimated. These scenarios involved river discharge decrease due to regional climate changes and socioeconomic and technological development that would lead to population growth and to the decrease of agricultural activities. The results indicated that in the case of discharge reduction only, the total nitrate and phosphate concentrations will be increased, while in case of combined land use and discharge changes, the concentration of nutrients will be decreased. Thus, a transboundary long-term management plan of the entire River is needed that would eliminate the pollution pressures and restore its good ecological status.
A total number of eight (8) tailings dams are found at the Kirki flotation plant and are either built on impermeable Neogene formations or permeable alluvial deposits of the Kirkalon and Eirini ...streams. The tailings dams were originally constructed without any environmental concerns, nowadays their embankments are highly eroded, and toxic material is readily transported to the nearby streams, resulting in degradation of the quality of both stream waters and sediments. Stream water sampling revealed that concentrations of dissolved Pb, Mn, Cd and SO
4
increase rapidly in the vicinity of the Kirki flotation plant. Four case-specific PHREEQC scenarios were employed including “Direct Precipitation,” “Evaporation,” “Mixing with Rain water” and “Mixing with Stream water” in order to investigate the effect of interaction between water accumulated on the surface of the tailings dams and the precipitation or dissolution of heavy metal-bearing phases that may control heavy metal solubility. All tests performed concluded that such interaction plays a very important role in the environmental behavior of the toxic tailings material of the Kirki flotation plant. Based on the results of the PHREEQC tests, the proposed rehabilitation plan includes the construction of a sealing system in order to eliminate tailings dam wall erosion and infiltration effects. The suggested plan is limited to dams 2, 3, 4, 5, 6, 7 and 8, whereas dam 1 is empty and requires no remediation. Additionally, and only for dams 5, 7 and 8, built on top of permeable alluvial formations a few meters above the ground water head, chemical improvement of the tailings material is suggested to limit toxic pollutants dissolution. In particular, installation of lime piles is proposed in order to further improve the quality of possible small-scale, low-quality percolating solutions that might migrate to underground aquifers.
•This work presents a new approach to the analysis of impact crater dimensions.•Measured depths are plotted against predicted depths in a diagram termed MPD.•Data in the MPD plot along parallel lines ...representing different crater ages.
Impact craters on the surface of Mars are degraded by erosion and infilling due to combinations of geological processes. These result in modifications of relative crater dimensions, including diameter increase and reduction of rim–floor depths. In principle, the longer a crater is exposed to geological processes, the more pronounced the modifications. Visualization and analysis of these effects are achieved by plotting the measured depths (M) of impact craters vs the corresponding theoretical depths (predicted: P) calculated from the crater diameters using depth/Diameter power laws. This type of diagram is referred to as MPD (measured depth vs predicted depth diagram). The advantage of using the MPD representation consists in the fact that the data plot along linear regressions, more easily interpreted than standard depth vs diameter diagrams.
As an example of application of the method, the MPD was used to discriminate different generations of impact craters in Terra Sabaea into four groups: T0 (fresh craters), T1, T2 and T3 (from younger to older), all located on the most ancient geological unit in the area (Npld). Other units in the area are Hpl3 and Hr, impacted only by craters belonging to group T0, suggesting that these units are stratigraphically correlated. The data of 5 craters in superposition relationships with the eastern reaches of Evros Vallis, one of the major valley networks in the area, were plotted in the diagram and assigned each to a regression depending on the location of their data points in relation to the prediction bands of the regressions. The craters superposed to the valley all belonged to T0, indicating that Evros Vallis has the same relative age of units Hpl3 and Hr.
A conceptual discussion of the results demonstrates that MPD statistics (a) are unaffected by the procedures used to acquire depths and diameters of impact craters and by the power laws used, and (b) can be interpreted irrespective of the sequence or combination of processes leading to modification of the crater morphometric data. These properties make the diagram a powerful statistical tool.
The present study endeavors to investigate the attitudes, opinions and perceptions of livestock farmers regarding the main problems they face and confine the development of livestock in the Greek ...region of Evros. Primary data were collected through a quantitative survey (structured questionnaire) with livestock farmers in the region. The analysis of the survey data was carried out with the use of descriptive statistics, Friedman’s test and factor analysis. The results indicate that strategies for livestock development in the region should take into account the great dissatisfaction that exists towards public authorities and the level of satisfaction as regards the non-governmental bodies. Furthermore, the economic objectives are of primary importance for livestock farmers, whereas they stress their interest in training and know-how. Particularly on issues pertaining to dairy livestock management, improving sanitation conditions and enhancing the quality, digestibility and production of animal feed.
In this study, various concentrations of nonessential toxic heavy metals (Cd, Cr, Ni and Pb) and the micronutrients (Cu, Zn, Mn) in twenty brown rice (O.sativa) and relevant paddy soil samples were ...investigated. The soil and brown rice samples from Evros-Ergene river basin were extracted for their total heavy metals content by dry digestion method and then determined by using ICP OES. The results of this study reveal that the concentrations of Cd, Cr and Ni in the soil of the studied sites are above the maximum permissible levels. The average concentration of all metals in brown rice samples is below the maximum permissible levels of the WHO guideline. The ranking order of bioaccumulation factor (BAF) for heavy metals is Zn > Cu > Mn > Ni> Cr = Cd = Pb, which indicaties that the accumulation of micronutrients was more than that of nonessential toxic heavy metals. It can be concluded that these rice samples cannot be regarded as a complete source to determine all metals posing threat to human health.
This study presents a methodology for siting municipal solid waste landfills, coupling geographic information systems (GIS), fuzzy logic, and multicriteria evaluation techniques. Both exclusionary ...and non-exclusionary criteria are used. Factors, i.e., non-exclusionary criteria, are divided in two distinct groups which do not have the same level of trade off. The first group comprises factors related to the physical environment, which cannot be expressed in terms of monetary cost and, therefore, they do not easily trade off. The second group includes those factors related to human activities, i.e., socioeconomic factors, which can be expressed as financial cost, thus showing a high level of trade off. GIS are used for geographic data acquisition and processing. The analytical hierarchy process (AHP) is the multicriteria evaluation technique used, enhanced with fuzzy factor standardization. Besides assigning weights to factors through the AHP, control over the level of risk and trade off in the siting process is achieved through a second set of weights, i.e., order weights, applied to factors in each factor group, on a pixel-by-pixel basis, thus taking into account the local site characteristics. The method has been applied to Evros prefecture (NE Greece), an area of approximately 4,000 km². The siting methodology results in two intermediate suitability maps, one related to environmental and the other to socioeconomic criteria. Combination of the two intermediate maps results in the final composite suitability map for landfill siting.
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