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991.
Cinzia Brugnano Raffaele D'Adamo Adele Fabbrocini Antonia Granata Giacomo Zagami 《Chemistry and Ecology》2013,29(5):461-480
Spatial and temporal variability in zooplankton was studied at eight stations located in the Lesina Lagoon (South Adriatic Sea) Salinity, temperature, dissolved oxygen and chlorophyll a (in the lagoon) at these stations were also assessed. The zooplankton community was characterised by clear seasonal oscillations and mostly represented by copepods and their larvae. The dominant copepod species were Calanipeda aquaedulcis and Acartia tonsa, which exhibited spatial–temporal segregation in the lagoon. C. aquaedulcis copepodites seemed to be better adapted to oligotrophic and oligohaline conditions compared with the A. tonsa population. The invasive species A. tonsa has completely replaced the formerly abundant Acartia margalefi. A positive correlation was found between abundances, total species numbers and trophic state. An increasing abundance trend was shown from the lagoon towards the sea. The highest diversity indices were recorded at the two channel inlets, during high tide due to the absence of a clear dominance of one or more coastal species and the co-occurrence of species of lagoon and marine origin. 相似文献
992.
993.
Synthesis and characterization of Cu(II), Ni(II), and Zn(II) Schiff bases complexes resulted from the condensation of salicylaldehyde derivatives with o-amino phenol were discussed using elemental analysis (carbon, hydrogen, and nitrogen), molar conductance, magnetic measurements, mass spectra, and electronic spectra. The essential bands of infrared, 1HNMR, and UV-Vis spectra as well as thermogravimetric analysis corresponding to the active groups within the three ligands and their complexes were interpreted. The dehydration and decomposition processes of the [Cu(H2L1)(H2O)](OAc)2, [Ni(H2L1)(H2O)]SO4 · H2O, [Zn(H2L1)(H2O)]SO4 · H2O, [Cu(H2L2)(H2O)](OAc)2, [Ni(H2L2)(H2O)]SO4 · H2O, [Zn(H2L2)(H2O)]SO4 · 2H2O, [Cu(H2L3)(H2O)](OAc)2 · H2O, [Ni(H2L3)(H2O)]SO4 · 2H2O, [Zn(H2L3)(H2O)]SO4 complexes were studied thermodynamically using the integral method applying the Coats–Redfern and Horowitz–Metzger equations and the thermodynamic parameters were calculated. It was found from the elemental analysis and the thermal studies, that the ligand behaves as tridentate ligand forming chelates with 1 : 1 (metal : ligand) stoichiometrically. The molar conductance measurements of the complexes in dimethyl sulfoxide solvent indicate that the complexes have an electrolytic nature. The biological activities of the three ligands in comparison with metal(II) complexes were studied against different Gram positive and Gram negative bacteria. 相似文献
994.
Loretta Müller Pierre Comte Jan Czerwinski Markus Kasper Andreas C.R. Mayer Adrian Schmid 《毒物与环境化学》2013,95(1):164-180
The aim of this study was to compare the cytotoxicity and the (pro-)inflammatory responses of two-stroke (direct injection and carburetor technology) and four-stroke scooter and diesel car exhaust emissions on lung cells in vitro. This was analyzed by exposing a 3D in vitro model of the epithelial airway (consisting of human bronchial epithelial cells (cell line 16HBE14o?) combined with human whole blood monocyte-derived macrophages and dendritic cells) to physically characterized exhaust emissions. Biological endpoints of cytotoxicity (lactate dehydrogenase release), as well as pro-inflammatory cytokine (tumor necrosis factor (TNF)-α) and inflammatory chemokine (interleukin(IL)-8) stimulation were examined. Two-stroke direct injection scooter exhaust contained the highest particle number concentration and nitrogen oxides (NO x ) concentrations and the emissions from the two-stroke carburetor scooter contained the highest hydrocarbon and lowest NO x concentrations. The four-stroke scooter emitted the highest carbon monoxide concentration whereas the cars emitted the lowest. The combination of various technical optimizations for the two-stroke direct injection scooter (particle filter, oxidative catalyst, better oil and fuel) reduced the total emissions strongly and the TNF-α concentration significantly (p?0.05). The cytotoxicity and the IL-8 concentration showed strong tendencies to be reduced. The analysis of the emissions of all tested two-stroke, four-stroke scooters and diesel cars showed a strong association between the adverse effects and the particle number concentration. 相似文献
995.
Developing indicators to more effectively evaluate poverty–environment dynamics and inform policy is an urgent research priority. It is critical that these indicators are used in ways that accurately represent the relationship they are meant to inform. This article evaluates the theory and use of poverty–environment indicators, a relatively new tool developed to aid in the design and evaluation of poverty reduction strategies in the context of environmental change. We argue that while they have great potential, in their current form and use, poverty–environment indicators may contribute to critical misunderstandings of processes on the ground. These issues stem from a problematic and largely unacknowledged process of simplifying particular poverty–environment relationships. This article lays out the problematic character of this simplification process, and suggests how we might address these problems to create more useful understandings of poverty–environment dynamics to inform policy. 相似文献
996.
《Process Safety and Environmental Protection》2014,92(6):888-895
The three layer artificial neural network model was applied to predict the degradation efficiency for carbamazepine in photocatalytic oxidation under UV radiation. Titania–zirconia was employed as a catalyst for the photooxidation. The catalyst was prepared using titanium isopropoxide and zirconium oxychloride by sol–gel method and characterized by transmission electron microscopy and BET analysis. Different process parameters such as, initial concentration of carbamazepine, pH of the solution, catalyst concentration and time of UV irradiation were employed as the input to the artificial neural network model and the output of the network was degradation efficiency of carbamazepine. The multilayer feed-forward networks with the Levenberg–Marquardt (trainlm) backpropagation training algorithm was used for the network training. The smallest mean square error was obtained for three-layer network with ‘logsig’ transfer function and five neurons in the hidden layer gave optimal results. A comparison between the predicted values and selective experimental data of degradation efficiency showed a high correlation coefficient (R2) of 0.997. 相似文献
997.
João L. Guilherme Victoria R. Jones Inês Catry Martin Beal Maria P. Dias Steffen Oppel Juliet A. Vickery Chris M. Hewson Stuart H. M. Butchart Ana S. L. Rodrigues 《Conservation biology》2023,37(1):e14002
The conservation of long-distance migratory birds requires coordination between the multiple countries connected by the movements of these species. The recent expansion of tracking studies is shedding new light on these movements, but much of this information is fragmented and inaccessible to conservation practitioners and policy makers. We synthesized current knowledge on the connectivity established between countries by landbirds and raptors migrating along the African–Eurasian flyway. We reviewed tracking studies to compile migration records for 1229 individual birds, from which we derived 544 migratory links, each link corresponding to a species’ connection between a breeding country in Europe and a nonbreeding country in sub-Saharan Africa. We used these migratory links to analyze trends in knowledge over time and spatial patterns of connectivity per country (across species), per species (across countries), and at the flyway scale (across all countries and all species). The number of tracking studies available increased steadily since 2010 (particularly for landbirds), but the coverage of existing tracking data was highly incomplete. An average of 7.5% of migratory landbird species and 14.6% of raptor species were tracked per country. More data existed from central and western European countries, and it was biased toward larger bodied species. We provide species- and country-level syntheses of the migratory links we identified from the reviewed studies, involving 123 populations of 43 species, migrating between 28 European and 43 African countries. Several countries (e.g., Spain, Poland, Ethiopia, Democratic Republic of Congo) are strategic priorities for future tracking studies to complement existing data, particularly on landbirds. Despite the limitations in existing tracking data, our data and results can inform discussions under 2 key policy instruments at the flyway scale: the African–Eurasian Migratory Landbirds Action Plan and the Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia. 相似文献
998.
Dechun Jiang Xumao Zhao Jordi López-Pujol Zhiqiang Wang Yanhua Qu Yanming Zhang Tongzuo Zhang Dayong Li Ke Jiang Bin Wang Chaochao Yan Jia-Tang Li 《Conservation biology》2023,37(4):e14069
Over the past 40 years, the climate has been changing and human disturbance has increased in the vast Qinghai–Tibet Plateau (QTP). These 2 factors are expected to affect the distribution of a large number of endemic vertebrate species. However, quantitative relationships between range shifts and climate change and human disturbance of these species in the QTP have rarely been evaluated. We used occurrence records of 19 terrestrial vertebrate species (birds, mammals, amphibians, and reptiles) occurring in the QTP from 1980 to 2020 to quantify the effects of climate change and anthropogenic impacts on the distribution of these 4 taxonomic groups and estimated species range changes in each species. The trend in distribution changes differed among the taxonomic groups, although, generally, ranges shifted to central QTP. Climate change contributed more to range variation than human disturbance (the sum of the 4 climatic variables contributed more than the sum of the 4 human disturbance variables for all 4 taxonomic groups). Suitable geographic range increased for most mammals, amphibians, and reptiles (+27.6%, +18.4%, and +27.8% on average, respectively), whereas for birds range decreased on average by 0.9%. Quantitative evidence for climate change and human disturbance associations with range changes for endemic vertebrate species in the QTP can provide useful insights into biodiversity conservation under changing environments. 相似文献
999.
ABSTRACTLand science has generated critical knowledge about how humans modify Earth’s surface and has advanced our understanding of land as a coupled human–environment system. However, to date, most work has been in frontier environments with less attention – both conceptually and empirically – on how urban land systems affect the carbon cycle. Much of what is known about urban areas and the carbon cycle is limited to aggregate levels of activities within urban areas, usually by sector, with little focus on how the spatial configuration of urban land systems affects carbon-emitting activities. Given that urban areas produce about 70% of global energy-related CO2 emissions, it is crucial to understand the relationship between urban environments, the activities they influence, and the resulting carbon emissions. This paper summarizes the current state of knowledge of how urban land systems affect carbon emissions and vulnerability, and identifies research gaps and opportunities for urban land science to contribute to climate change science, particularly through land architecture. We argue that more attention to urban land science conceptualization, measurement, and analysis would contribute to both fundamental knowledge about urban systems, as well as help identify policies and strategies for mitigation and adaptation to climate change at the urban scale. 相似文献
1000.