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151.
Recent studies have emphasised that organisms can experience physiological stress well within their geographic range limits. Developing methods for mechanistically predicting the presence, absence and physiological performance of organisms is therefore important because of the ongoing effects of climate change. In this study, we merged a biophysical–ecological (BE) model that estimates the aquatic (high tide) and aerial (low tide) body temperatures of Mytilus galloprovincialis with a Dynamic Energy Budget (DEB) model to predict growth, reproduction and mortality of this Mediterranean mussel in both intertidal and subtidal environments. Using weather and chlorophyll-a data from three Mediterranean sites along the Italian coasts, we show that predictions of sublethal and lethal (acute) stress can potentially explain the observed distribution (both presence and absence) of mussels in the intertidal and subtidal zones, and the maximum size of animals in the subtidal zones. Importantly, our results suggest that different mechanisms limit the intertidal distribution of mussels, and that these mechanisms do not follow a simple latitudinal gradient. At the northernmost site (Palermo), M. galloprovincialis appears to be excluded from the intertidal zone due to persistent exposure to lethal aerial temperatures, whereas at the southernmost sites (Porto Empedocle and Lampedusa) sublethal stress is the most important driver of mussel intertidal distribution. Our predictions provide a set of hypotheses for future work on the role of climate change in limiting intertidal distribution of mussels in the Mediterranean.  相似文献   
152.
The effects of exposure of tilapia (Oreochromis mossambicus) to sublethal concentrations of lead on hematological and immunological parameters were investigated. The fish were semistatically exposed to low (L) (0.5 mg L?1), medium (M) (2.5 mg L?1), and high (H) (5 mg L?1) lead concentrations for 14 days. At the end of the trial, red blood cell (RBC) count, hematocrit (Hct) ratio and hemoglobin levels showed significant decreases in M and H groups, while RBC was significantly increased in L group compared to control group. Lysozyme activity showed a decrease in all groups on day 14 compared to control. A decrease in myeloperoxidase activity was seen in M and H groups on day 7, and in all treatment groups on day 14. In conclusion, it was found that exposure of O. mossambicus to lead concentrations affected hematological and immunogical parameters adversely.  相似文献   
153.
In the last few decades, metal oxide nanoparticles have shown impact in various areas, and such an impact causes an increased release in a different environment like soil, water, or air. A limited number of studies on soils showed that the biochemical parameters were affected by the metal oxide nanoparticles. However, the influence of metal oxide nanoparticles on soil elements has not been investigated. For this aim, zinc oxide nanoparticles were applied to two different soils; also, the effect of planting on soil elements was investigated via the cultivation of various plants roots (taproots, fibrous, bulb). Soils were treated with zinc oxide nanoparticles at 0, 1.0 and 20.0?mg during 4 weeks. Then, surface soil samples were collected and digested using an acid digestion procedure. Some biochemically important elements (Ca, Zn, Mg, Fe, Al, Cu, Co, Ni) were determined using a microwave plasma atomic emission spectrometer. The effect of time and dose-dependent zinc oxide nanoparticles on the element contents of different soils was investigated during planting, and the results were statistically evaluated.  相似文献   
154.
The aim of this study is to propose the use of a functional data analysis approach as an alternative to the classical statistical methods most commonly used in oceanography and water quality management. In particular we consider the prediction of total suspended solids (TSS) based on remote sensing (RS) data. For this purpose several functional linear regression models and classical non-functional regression models are applied to 10 years of RS data obtained from medium resolution imaging spectrometer sensor to predict the TSS concentration in the coastal zone of the Guadalquivir estuary. The results of functional and classical approaches are compared in terms of their mean square prediction error values and the superiority of the functional models is established. A simulation study has been designed in order to support these findings and to determine the best prediction model for the TSS parameter in more general contexts.  相似文献   
155.
This study investigated the process of taking action to mitigate damage and prepare for an earthquake at the individual level. Its specific aim was to identify the factors that promote or inhibit individuals in this process. The study was conducted in Istanbul, Turkey—where an earthquake is expected soon—in May and June 2006 using qualitative methods. Within our conceptual framework, three different patterns emerged among the study subjects. Outcome expectancy, helplessness, a low socioeconomic level, a culture of negligence, a lack of trust, onset time/poor predictability, and normalisation bias inhibit individuals in this process, while location, direct personal experience, a higher education level, and social interaction promote them. Drawing on these findings, the paper details key points for better disaster communication, including whom to mobilise to reach target populations, such as individuals with direct earthquake experience and women.  相似文献   
156.
The transfer of peat organic matter (OM) from tidal pools of upper littoral to downstream rocky shores and its potential incorporation into marine biota were investigated using the stable isotope approach. Samplings were carried out in September 2004 in two SW Icelandic sites (Osar and Hvassahraun), where we selected (1) areas with shores where grass gently declined towards rocks and, on reaching the sea line, formed small tidal peat pools and (2) areas where grass and rocky shores were not contiguous, rather the grass lower limits were several hundreds of meters back from the shore. In both grass and no grass areas, in the intertidal zone, all benthic organisms and all potential OM sources were sampled. Dominant macroalgae were Ascophyllum nodosum ([Linnaeus] Le Jolis) and Fucus vesiculosus Linnaeus. In grass sites, organisms partially reflected the isotopic composition of peat OM, while in no grass sites, peat represented only a negligible amount of available OM, or its signal was totally absent from the environment. Intertidal organisms could rely on peat both directly by suspension feeding, grazing or scavenging and indirectly by predation (crabs) on low level consumers (barnacles).  相似文献   
157.
This study reports the optimization of a binary dispersive liquid-liquid microextraction method for the determination of iprodione, procymidone, and chlorflurenol by gas chromatography mass spectrometry. The study was aimed at using two extraction solvents to increase the extraction efficiency of all analytes. The binary solvents recorded results higher than the mono-solvents. After examining the effects of main experimental parameters and their interactions by analysis of variance, 200 μL of binary mixture (dichloromethane and 1,2-dichloroethane), 2.5 mL of ethanol, and 15 s vortex were obtained as optimum parameters. The detection and quantification limits calculated for the analytes were found to be between 0.30–1.6 and 1.0–5.3 ng/mL, respectively. Enhancement in detection power calculated as a ratio of the binary extraction detection limit to the detection limit of direct GC-MS analysis was 105-, 214-, and 233-fold for chlorflurenol, iprodione, and procymidone, respectively. In order to check the accuracy of the developed method, recovery study was performed. Water sampled from a lake and two wastewater samples from treatment facilities were spiked at two concentrations, and the percent recovery calculated for the samples ranged between 87 and 116%. These results confirmed the suitability of the method to real samples for accurate determination of the analytes at trace levels.  相似文献   
158.
This study aims to identify precipitation, throughfall, stemflow, precipitation, and interception processes in pure black pine, pure Scots pine, and mixed black pine–Scots pine forest ecosystems and present the precipitation partitioning according to different stand types. Throughfall and stemflow measurements were performed using five standard precipitation gauges in a pilot area established to represent pure black pine, pure Scots pine, and mixed black pine–Scots pine stands in the Bezirgan Basin. The total precipitation was measured in an open field close to the study area. Throughfall values were calculated as the percentage of precipitation measured in an open field. According to the results of the study, the throughfall values were 69.8% in black pine, 73.9% in Scots pine, and 77.7% in the mixed black pine–Scots pine stands; the stemflow values were 2.6% in black pine, 5.9% in Scots pine, and 3.1% in the mixed black pine–Scots pine stands; the amounts of precipitation reaching the forest floor were 72.3% in black pine, 79.8% in Scots pine, and 80.7% in the mixed black pine–Scots pine stands; and the interception values were found to be 27.7% in black pine, 20.2% in Scots pine, and 19.2% in the mixed black pine–Scots pine stands.  相似文献   
159.
Regional Environmental Change - Climate change and a growing population around the Mediterranean Rim are increasing the need for water and, consequently, the pressure on resources in terms of both...  相似文献   
160.
A sustainable source of energy production can be provided using renewable resources. For instance, biomass is transformed into biofuels using several techniques such as supercritical fluid extraction, an effective thermochemical process. Here we review results on biofuels obtained from lignocellulosic and algal biomass using supercritical fluids. Biofuel yield and composition are controlled by operating conditions such as extraction temperature, pressure, biomass and solvent type, and the presence of catalysts. The extraction temperature is the major factor controlling biofuel yield. Biofuel yields can also be improved with the use of catalysts. Major compounds in biofuels from lignocellulosic biomass are phenols, catechols, guaiacols, syringols, syringaldehydes, syringyl acetone, acids, and esters. Most of these compounds are produced by lignin decomposition in lignocellulose. Furfural and derivatives are produced by the decomposition of cellulose and hemicellulose. Fatty acid alkyl esters are formed from lignin fragmentation by condensation of compounds bearing C–O or C=O. Prominent compounds in biofuels from algal biomass are saturated or unsaturated fatty acid alkyl esters.  相似文献   
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