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Since the end of the 1970s, the southern European countries have shown an exceptional reduction in fertility rate. From the
highest levels among the developed nations, these countries dropped beneath the substitution rate level: in Greece there is
an average of about 1.5 children per woman, and Italy (starting three to four years ago), with 1.3 children per woman, is
now the country with the lowest fecundity rate in the world. Land-use planning in southern European small islands therefore
requires substantial revision. In the areas where western civilization began, which are highly populated and have a long history,
cultural and ethnic aspects of tradition are fundamental to environmental management and to the defense of historical heritage.
They also place a strong value on sustaining tourism, the most relevant economic activity, that allows them to survive and
maintain a high welfare level. For some decades they have had populations with a marked presence of young people and high
emigration rates, but now they are fast becoming dominated by the elderly and must prepare for a period of fast reduction
in youth of the workforce, while the peripheral areas of Asia and Africa are entering a sudden demographic growth phase.
The demographic structure has also been deeply altered both by previous migrations and by random variations, as usually happens
in all small communities. Social services for younger and older people have had to be adapted rapidly, reorganizing high-school
management, hospital and health-care structures, in-house assistance, and so on. There is a need to rethink the job market
and favor the immigration of highly specialized workers, which is a necessity for technical evolution. Sustainable development
is constrained nowadays not only by the scarcity of natural resources, but also by the quality and quantity of human resources.
Proper policies for population and land-use planning are highly correlated factors; they have to be considered with respect
of these new, rapid demographic changes. 相似文献
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Angelo Pecci Ganapati Patil Orazio Rossi Pierfrancesca Rossi 《Environmental and Ecological Statistics》2010,17(4):473-502
The environmental decision-maker is aware of the increasing difficulties in finding sufficient financial resources for nature
conservation. So he must focus his attention on ecological situations that more than the others merit considering and defending
because of elevated value but also because of risk for their intrinsic characteristics and for human pressure acting on them.
Usually an ecological scientist focuses his attention on the natural patches of the landscape, analyzing their peculiar ecological
traits forgetting that, even if we want to protect some environmental critical situations, this can be done only moving to
the administrative partition of the territory since the central and local environmental stakeholders have primary interest
in providing funds to those involved in those critical situations. The present work shows a methodological approach, consisting
of a set of statistical and geoinformational tools, considering both ecological and socio-demographical indicators. The goal
is not simply to give some general guidelines for environmental policies to the involved stakeholders but focuses more on
finding out which administrative local partitions in a study area are more worthy to receive urgently the priority funds for
biodiversity protection to face critical environmental situations often due to a combination of intrinsic ecological parameters
and external human pressure ones. Obtaining results that cover 5% of the Communes involved in the area seems to be a realistic
result that a decision-maker can support and fund. Methodologically and geospatial data analytically, the investigation offers
interesting challenges for surveillance geoinformatics of hotspot detection and prioritization, because of the presence of
multiple hotspots and multiple sets of multiple indicators. 相似文献
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Hinck JE Norstrom RJ Orazio CE Schmitt CJ Tillitt DE 《Environmental pollution (Barking, Essex : 1987)》2009,157(2):582-591
Organochlorine pesticide and total polychlorinated biphenyl (PCB) concentrations were measured in largemouth bass from the Tombigbee River near a former DDT manufacturing facility at McIntosh, Alabama. Evaluation of mean p,p′- and o,p′-DDT isomer concentrations and o,p′- versus p,p′-isomer proportions in McIntosh bass indicated that DDT is moving off site from the facility and into the Tombigbee River. Concentrations of p,p′-DDT isomers in McIntosh bass remained unchanged from 1974 to 2004 and were four times greater than contemporary concentrations from a national program. Total DDT in McIntosh bass exceeded dietary effect concentrations developed for bald eagle and osprey. Hexachlorobenzene, PCBs, and toxaphene concentrations in bass from McIntosh also exceeded thresholds to protect fish and piscivorous wildlife. Whereas concentrations of DDT and most other organochlorine chemicals in fish have generally declined in the U.S. since their ban, concentrations of DDT in fish from McIntosh remain elevated and represent a threat to wildlife. 相似文献
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Roingeard Camille Monnereau Alain Goujon Stéphanie Orazio Sébastien Bouvier Ghislaine Vacquier Blandine 《Environmental science and pollution research international》2021,28(32):43190-43216
Environmental Science and Pollution Research - Incidence rates of hematological malignancies have been constantly increasing over the past 40 years. In parallel, an expanding use of agricultural... 相似文献
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Island biogeographic theory offers a powerful conceptual framework for understanding and managing insular diversity. The human
impact on insular environments is constantly growing, especially because of tourism. We performed a simulation study aimed
at improving the understanding of the role of disturbance in islands. We also built an individual-oriented computer model
of an archipelago subjected to chronic disturbance of varying degree. Results are discussed in the light of island biogeographic
theory. Relevant results show the importance of autoecological characteristics of the species considered, regarding the attainment
of equilibrium and the species-area relationship in both disturbed and undisturbed cases. The possibility of bias in the predictions
of the equilibrium model is pointed out. Fundamental criticisms concerning the ecological relevance of the equilibrium theory
are discussed. 相似文献
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Sortino O Dipasquale M Montoneri E Tomasso L Perrone DG Vindrola D Negre M Piccone G 《Waste management (New York, N.Y.)》2012,32(10):1792-1801
Municipal bio-refuse (CVD), containing kitchen wastes, home gardening residues and public park trimmings, was treated with alkali to yield a soluble bio-organic fraction (SBO) and an insoluble residue. These materials were characterized using elemental analysis, potentiometric titration, and 13C NMR spectroscopy, and then applied as organic fertilizers to soil for tomato greenhouse cultivation. Their performance was compared with a commercial product obtained from animal residues. Plant growth, fruit yield and quality, and soil and leaf chemical composition were the selected performance indicators. The SBO exhibited the best performance by enhancing leaf chlorophyll content, improving plant growth and fruit ripening rate and yield. No product performance-chemical composition relationship could be assessed. Solubility could be one reason for the superior performance of SBO as a tomato growth promoter. The enhancement of leaf chlorophyll content is discussed to identify a possible link with the SBO photosensitizing properties that have been demonstrated in other work, and thus with photosynthetic performance. 相似文献
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Field and laboratory studies were conducted to investigate the persistence of chlordane in the aquatic and terrestrial environment. The laboratory data show that the transformation and loss of the chlordane constituents is dependent on soil characteristics. The overall rate of loss is also dependent on the depth of application, being significantly lower at greater depths. The field data show a strong correlation between urban development and residue concentration levels. 相似文献
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