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821.
822.
823.
Nicolas Goñi John Logan Haritz Arrizabalaga Marc Jarry Molly Lutcavage 《Marine Biology》2011,158(5):1057-1073
This study aims to describe the variability of albacore (Thunnus alalunga) diet in the Northeast Atlantic and Mediterranean Sea and to identify possible relationships between this variability and
the features of different feeding areas, the behavior, and the energetic needs of albacore. Stomach contents from albacore
caught in five zones of the Bay of Biscay and surrounding waters (n = 654) and three zones of the Mediterranean Sea (n = 152) were analyzed in terms of diet composition and stomach fullness. Carbon and nitrogen stable isotope and C/N ratios
were measured for white muscle and liver from albacore in the Bay of Biscay (n = 41) and Mediterranean Sea (n = 60). Our results showed a spatial, seasonal, inter-annual, and size-related variability in the diet of albacore. Albacore
diet varied by location in the Mediterranean Sea, with a particularly high proportion of cephalopods, and low δ15N values in the Tyrrhenian Sea. In the Northeast Atlantic, albacore consumed a higher proportion of crustaceans and a lower
proportion of fishes in the most offshore sampling zone than inshore. The digestion states of the major prey reflected a diurnal
feeding activity, indicative of feeding in deeper waters offshore, whereas on the continental slope, feeding probably occurred
in surface waters at night. Important seasonal and inter-annual diet variability was observed in the southeast of the Bay
of Biscay, where preferred albacore prey appeared to be anchovy (Engraulis encrasicolus). Stomach fullness was inversely related to body size, probably reflecting higher energetic needs for smaller individuals.
Albacore from the Bay of Biscay had significantly lower δ13C and higher δ15N values compared with albacore from the Mediterranean Sea, indicative of regional baseline shifts, and trophic position and
muscle lipid stores in albacore increased with body size. 相似文献
824.
Milačič R Zuliani T Oblak T Mladenovič A Ančar JŠ 《Journal of environmental quality》2011,40(4):1153-1161
Electric arc furnace (EAF) steel slag can be used as an alternative high-quality material in road construction. Although asphalts with slag aggregates have been recognized as environmentally acceptable, there is a lack of data concerning the potential leaching of toxic Cr(VI) due to the highly alkaline media of EAF slag. Leaching of selected water extractable metals from slag indicated elevated concentrations of total chromium and Cr(VI). To estimate the environmental impacts of asphalt mixes with slag, leachability tests based on diffusion were performed using pure water and salt water as leaching agents. Compact and ground asphalt composites with natural aggregates, and asphalt composites in which the natural aggregates were completely replaced by slag were prepared. The concentrations of total chromium and Cr(VI) were determined in leachates over a time period of 6 mo. After 1 and 6 mo, the concentrations of some other metals were also determined in the leachates. The results indicated that chromium in leachates from asphalt composites with the addition of slag was present almost solely in its hexavalent form. However, the concentrations were very low (below 25 μg L) and did not represent an environmental burden. The leaching of other metals from asphalt composites with the addition of slag was negligible. Therefore, the investigated EAF slag can be considered as environmentally safe substitute for natural aggregates in asphalt mixes. 相似文献
825.
Una Andersone Ieva Druva-Lūsīte Baiba Ieviņa Andis Karlsons Jevgenija Ņečajeva Ineta Samsone Gederts Ievinsh 《Journal of Coastal Conservation》2011,15(4):509-522
Eryngium maritimum is a perennial species growing exclusively in a coastal littoral zone both on sand dunes and shingle beach and indicated
as declining in Northern Europe. The objective of the present study was to prove the use of nondestructive physiological measurement
methods to access physiological status of endangered plants, using E. maritimum as a model species. Plants from two Latvian sites were studied in comparison with other populations in Northern Europe (Estonia,
Lithuania, Poland, United Kingdom) to find out if local differences in environmental factors affect vitality of E. maritimum individuals. Noninvasive chlorophyll analysis and chlorophyll a fluorescence measurements were used as indicators of plant physiological status through characterization of various aspects
of photochemistry of photosystem II activity. Dynamics and morphology of individuals were investigated for evaluation of clonal
growth potential of E. maritimum in natural conditions. Highly fluctuating trend of dynamics of individuals (within 40 groups at two Latvian sites) was established
for E. maritimum in natural conditions over a five-year period. Disturbance of individuals lead to formation of new shoots from nodal root
meristems. An exponential regression between fluorescence parameters FV/FM and Performance Index and summary monthly precipitation was found indicating that E. maritimum plants had significant tolerance to water shortage together with susceptibility to increased precipitation. Negative correlation
between leaf chlorophyll content and more northern localization of individuals was found (r = 0.95 and r = 0.94, for generative and vegetative shoots, respectively). Northern populations of E. maritimum are endangered by high precipitation in conditions of low air temperature, leading to decrease of photosynthetic productivity
and overall physiological status. High developmental plasticity at the root level leads to clonal growth and an efficient
survival and relatively long life span of E. maritimum individuals. Chlorophyll a fluorescence is a useful method to search for the effect of suboptimal conditions on physiological status of endangered plant
species without elimination and disturbance of individuals. 相似文献
826.
The main objective of this study was to statistically evaluate the significance of seasonal groundwater quality change and to provide an assessment on the spatial distribution of specific groundwater quality parameters. The studied area was the Mount Nif karstic aquifer system located in the southeast of the city of Izmir. Groundwater samples were collected at 57 sampling points in the rainy winter and dry summer seasons. Groundwater quality indicators of interest were electrical conductivity (EC), nitrate, chloride, sulfate, sodium, some heavy metals, and arsenic. Maps showing the spatial distributions and temporal changes of these parameters were created to further interpret spatial patterns and seasonal changes in groundwater quality. Furthermore, statistical tests were conducted to confirm whether the seasonal changes for each quality parameter were statistically significant. It was evident from the statistical tests that the seasonal changes in most groundwater quality parameters were statistically not significant. However, the increase in EC values and aluminum concentrations from winter to summer was found to be significant. Furthermore, a negative correlation between sampling elevation and groundwater quality was found. It was shown that with simple statistical testing, important conclusions can be drawn from limited monitoring data. It was concluded that less groundwater recharge in the dry period of the year does not always imply higher concentrations for all groundwater quality parameters because water circulation times, lithology, quality and extent of recharge, and land use patterns also play an important role on the alteration of groundwater quality. 相似文献
827.
Ivana Teodorović Sonja Kaišarević Kristina Pogrmić-Majkić Ivana Planojević Svetlana Fa Vanja Dakić Jelena Hrubik Branka Glišić Radmila Kovačević 《Environmental Sciences Europe》2011,23(1):1-9
Background
In order to map exceedances of critical atmospheric deposition loads for nitrogen (N) surface data on the atmospheric deposition of N compounds to terrestrial ecosystems are needed. Across Europe such information is provided by the international European Monitoring and Evaluation Programme (EMEP) in a resolution of 50 km by 50 km, relying on both emission data and measurement data on atmospheric depositions. The objective of the article at hand is on the improvement of the spatial resolution of the EMEP maps by combining them with data on the N concentration in mosses provided by the International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation) of the United Nations Economic Commission for Europe (UNECE) Long-range Transboundary Air Pollution (LTRAP) Convention.Methods
The map on atmospheric depositions of total N as modelled by EMEP was intersected with geostatistical surface estimations on the N concentration in mosses at a resolution of 5 km by 5 km. The medians of the N estimations in mosses were then calculated for each 50 km by 50 km grid cell. Both medians of moss estimations and corresponding modelled deposition values were ln-transformed and their relationship investigated and modelled by linear regression analysis. The regression equations were applied on the moss kriging estimates of the N concentration in mosses. The respective residuals were projected onto the centres of the EMEP grid cells and were mapped using variogram analysis and kriging procedures. Finally, the residual and the regression map were summed up to the map of total N deposition in terrestrial ecosystems throughout Europe.Results and discussion
The regression analysis of the estimated N concentrations in mosses and the modelled EMEP depositions resulted in clear linear regression patterns with coefficients of determination of r 2 = 0.62 and Pearson correlations of r p = 0.79 and Spearman correlations of r s = 0.70, respectively. Regarding the German territory a nationwide mean of 18.1 kg/ha/a (standard deviation: 3.49 kg/ha/a) could be derived from the resulting map on total N deposition in a resolution of 5 km by 5 km. Recent updates of the modelled atmospheric deposition of N provided a similar estimate for Germany.Conclusions
The linking of modelled EMEP data on the atmospheric depositions of total N and the accumulation of N in mosses allows to map the deposition of total N in a high resolution of 5 km by 5 km using empirical moss data. The mapping relies on the strong statistical relationship between both processes that are physically and chemically related to each other. The mapping approach thereby relies on available data that are both based on European wide harmonized methodologies. From an ecotoxicological point of view the linking of data on N depositions and those on N bioaccumulation can be considered a substantial progress. 相似文献828.
Ruczyńska WM Szlinder-Richert J Malesa-Ciećwierz M Warzocha J 《Journal of environmental monitoring : JEM》2011,13(9):2535-2542
The concentrations of fifteen PAH compounds in samples of sediment and blue mussel tissue (Mytilus trossulus) were measured. In addition, the biliary polycyclic aromatic hydrocarbon metabolites present in flounder (Platichthys flesus) were analysed. Two methods were used in the analysis of PAH metabolites; high performance liquid chromatography (HPLC) and fixed wavelength fluorescence (FF). The major PAH metabolite which could be measured using the HPLC method was 1-OH pyrene. It was possible to detect 1-OH Phe and 3-OH B[a]P in 70 and 24 samples respectively, of the 87 samples analysed. However, the concentrations of 1-OH Phe and 3-OH B[a]P were below or near to the LOQ (0.002 μg ml(-1) bile). The bile of flounder samples from the Gulf of Gdańsk had 1-OH Pyr concentrations which ranged from 0.019 to 0.066 μg ml(-1) bile. The high linear correlation observed between the quantity of 1-OH pyrene determined by the HPLC-F method and the content of the sum of pyrene-type PAHs obtained by the FF method indicated the FF method of determination of pyrene-type PAH metabolites can be used as a screening method. The content of ∑(15)PAHs in sediments collected in the Gulf of Gdansk, in 2008, ranged from 29.3 to 103 μg kg(-1) dw. In mussel tissue ∑(15)PAHs concentrations were between 173.2 μg kg(-1) dw and 237.7 μg kg(-1) dw. All concentrations measured in the current study, in mussel tissue, were below the OSPAR toxicity threshold values. 相似文献
829.
Ivančev-Tumbas Ivana Lammel Gerhard 《Environmental science and pollution research international》2021,28(42):59317-59318
Environmental Science and Pollution Research - Recently, nearly 500 study programmes related to environmental disciplines were detected in Europe (Lammel et al, Environ Sci Pollut Res 21:7211-7218... 相似文献
830.
Aleksandar Aleksić Miladin Stefanović Slavko Arsovski Danijela Tadić 《Journal of Loss Prevention in the Process Industries》2013,26(6):1238-1245
In order to establish adequate tools for the modern business environment, and with a need for new mechanisms with the goal of overcoming crisis and emerging disorder, the concept of organizational resilience has emerged. A high level of organizational resilience represents one of an organization's target values during a normal period of operation. In a period of crisis, the presence of resilience is even more needed; this is emphasized in the process industry because in these conditions when one process fails it may cause significant problems in other processes. The contribution of this paper is shown through a fuzzy mathematical model for assessment of organizational resilience potential in SMEs of the process industry. The model is verified through an illustrative example where obtained data suggest measures which should enhance business strategy and improve organizational resilience factors. This study forms the basis for a survey that may include a significant number of organizations from one region and future improvement based on benchmark and knowledge sharing. 相似文献