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281.
How an economically affordable, environmentally effective and socially acceptable municipal solid waste management system can be developed is currently unclear. Considerable research has been carried out on the practical aspects of municipal waste management (i.e. transport, treatment and disposal) and how citizens feel about source separation, recycling, incineration and landfill but the perspective of the waste manager within the context of long term planning is often ignored. In this study, waste managers from 11 different leading-edge European municipal solid waste programs in nine different countries were interviewed. The economic, social, political, environmental, legal and technical factors of their specific programs were explored and analyzed. The transition of municipal solid waste management to urban resources management was observed and key ‘system drivers’ for more sustainable waste management practices were identified. Programs visited were: Brescia (I), Copenhagen (DK), Hampshire (UK), Helsinki (FI), Lahn-Dill-Kreis (D), Malmö (SE), Pamplona (E), Prato (I), Saarbrücken (D), Vienna (A), and Zürich (CH). 相似文献
282.
SUMMARY Over-population in relation to poor land productivity and cultivation in less fertile lands is resulting in land degradation and deforestation in UP hills. Growing demand of more food production and increasing need for more cash in hand have forced the hill people to cultivate all kinds of land, resulting in the denudation of land resources and soil erosion. These changes resulted in out migration of the area's human resource. A new management system for the revival of natural resources and the sustainable utilization of the area's human population and livestock has been proposed, involving active local participation in order to change the existing land-use to a system based on the soil fertility scale. 相似文献
283.
Within the context of its institutional scientific support to the European Commission, in 2005 the Radioactivity Environmental Monitoring (REM) group at the Joint Research Centre of the European Commission, started to explore the possibility of mapping indoor radon in European houses as a first step towards preparing a European Atlas of Natural Radiations. The main objective of such an atlas is to contribute to familiarizing the public with its naturally radioactive environment. The process of preparing the atlas should also provide the scientific community with a database of information that can be used for further studies and for highlighting regions with elevated levels of natural radiation. This document presents the status of the European indoor radon (Rn) map, first statistical results, and outlines of forthcoming challenges. 相似文献
284.
Richon P Perrier F Koirala BP Girault F Bhattarai M Sapkota SN 《Journal of environmental radioactivity》2011,102(2):88-102
Temporal variation of radon-222 concentration was studied at the Syabru-Bensi hot springs, located on the Main Central Thrust zone in Central Nepal. This site is characterized by several carbon dioxide discharges having maximum fluxes larger than 10 kg m−2 d−1. Radon concentration was monitored with autonomous Barasol™ probes between January 2008 and November 2009 in two small natural cavities with high CO2 concentration and at six locations in the soil: four points having a high flux, and two background reference points. At the reference points, dominated by radon diffusion, radon concentration was stable from January to May, with mean values of 22 ± 6.9 and 37 ± 5.5 kBq m−3, but was affected by a large increase, of about a factor of 2 and 1.6, respectively, during the monsoon season from June to September. At the points dominated by CO2 advection, by contrast, radon concentration showed higher mean values 39.0 ± 2.6 to 78 ± 1.4 kBq m−3, remarkably stable throughout the year with small long-term variation, including a possible modulation of period around 6 months. A significant difference between the diffusion dominated reference points and the advection-dominated points also emerged when studying the diurnal S1 and semi-diurnal S2 periodic components. At the advection-dominated points, radon concentration did not exhibit S1 or S2 components. At the reference points, however, the S2 component, associated with barometric tide, could be identified during the dry season, but only when the probe was installed at shallow depth. The S1 component, associated with thermal and possibly barometric diurnal forcing, was systematically observed, especially during monsoon season. The remarkable short-term and long-term temporal stability of the radon concentration at the advection-dominated points, which suggests a strong pressure source at depth, may be an important asset to detect possible temporal variations associated with the seismic cycle. 相似文献
285.
A. J. Plater J. F. Boyle C. Mayers S. D. Turner R. W. Stroud 《Regional Environmental Change》2006,6(1-2):71-85
The limnological record of human impact on catchment land cover and on lake sedimentation during the historical period has
been established for Pinto Lake in Central Coastal California. In addition, the sedimentary record of the ‘pre-impact’ condition
preserves evidence of a climatic control on the nature of lake sedimentation. Chronological marker horizons have been determined
using pollen data in combination with the documented land-use history and introductions of exotic species. Further chronological
data have been determined using 14C and 137Cs. The impact of Mexican and Euro-American immigrants and their ‘imported’ land-use practices is clearly reflected in an
order of magnitude increase in the rate of lake sedimentation to c. 9 kg m−2 year−1 (c. 2 cm year−1) between 1770 and 1850. Here, the occurrence of exotic plant species indicates disturbance as early as c. 1769–1797, whilst
redwood deforestation between 1844 and 1860 represents the most significant human impact. Changes in the nature of sedimentation
prior to this reveal a high degree of sensitivity to changes in precipitation where subtle decreases in lake level and the
supply of runoff-derived mineral matter have resulted in two periods of organic lake sedimentation c. 650–900 and 1275–1750. Set against this background condition of high sensitivity, the dramatic impacts of Euro-American settlement
are unsurprising.
An erratum to this article can be found at 相似文献
286.
Tobias Kuemmerle Daniel Müller Patrick Griffiths Marioara Rusu 《Regional Environmental Change》2009,9(1):1-12
The drastic socio-economic and political changes that occurred after the breakdown of socialism in Eastern Europe triggered
widespread land use change, including cropland abandonment and forest cover changes. Yet the rates and spatial patterns of
post-socialist land use change remain largely unclear. We used Landsat TM/ETM+ images to classify land cover maps and assess
landscape pattern changes from 1990 to 2005 in Argeş County, Southern Romania. Cropland abandonment was the most widespread
change (21.1% abandonment rate), likely due to declining returns from farming, tenure insecurity, and demographic developments
during transition. Forest cover and forest fragmentation remained remarkably stable during transition, despite widespread
ownership transfers. Cropland abandonment provides opportunities for increased carbon sequestration, but threatens cultural
landscapes and biodiversity. Continued monitoring is important for assessing whether abandoned croplands will eventually reforest
or be put back into production and to better understand the consequences of post-socialist land use change for ecosystems
and biodiversity. 相似文献
287.
The giant panda was found on Mount Shennongjia in Central China for thousands of years but vanished in the late 19th century. The possibility for reintroducing the giant panda in Shennongjia is discussed in terms of food availability, carrying capacity, and predicted bamboo flowering. Three species (Fargesia spathacea, F. murielae, and Yushania confusa) are considered the preferred forage bamboos, which could feed 193–223 giant pandas. However, in 1879–1888 these three species synchronously flowered and died back. In the past, such bamboo flowering usually forced the panda to migrate to a new habitat where forage bamboos were available. But since the 19th century, Shennongjia has become separated from other panda habitats by densely populated agricultural zones. Multi-species flowering of the forage bamboo and isolating of the habitat might caused the extinct of the giant panda in Shennongjia. If the flowering cycle of the bamboo is genetically fixed, the next synchronous flowering of two staple food species (F. spathacea and F. murielae) may occur in 2436–2439. It means that the food supply is dependable in Shennongjia for reintroducing the giant panda before 2436. 相似文献
288.
The Central Himalayan region is suffering from severe ecological problems as a consequence of deforestation and that threatens
the subsistence population of the region. We analyze this problem and propose a plan for ecologically sustainable development
for the region based on an analysis of the interrelationships of various ecosystems, particularly cropland and forest ecosystems,
around which most human activities are concentrated. Each energy unit of agronomic yield leads to expenditure of about 12
energy units of forest/grazing land energy. Because with rapidly declining forest area, this form of agriculture is no longer
sustainable and cannot be converted into a fossil fuel-based agriculture, we propose that agriculture in the mountain region
has to be largely replaced with farm forests to revitalize the environment and to generate the basic needs of the subsistence
economy of the hill population whose food grain needs can be met from the plains. We conclude by describing the advantages
that are likely to accrue to the people for their long-term future. In terms of both energy and money, the value of resources
collected from the forest to support agriculture in the present systems far exceeds the value of food grain that would be
required to enable the proposed farm forest-based systems to function. At regional level, the proposed system would generate
more energy than the existing systems, not only because the productivity of forest is about tenfold greater than that of cropland,
but also because the proposed plan promotes recovery of various ecosystems. 相似文献
289.
自然中心主义环境伦理思想作为目前最为热门的学科之一,自然同其它学科一样,有它产生的思想根源、现实缘由和直接的动因。工业社会的精神失落和蓬勃兴起的绿色运动是其思想诱因与直接动因,而它形成的现实缘由则主要是全球面临的生态困境以及对人与自然关系的重新认识。 相似文献
290.
Due to rapid industrialization, with high population density and constraints of land, it is expected that level of risks arising from the hazardous industries will increase in India in the coming decades. However, 30 years after the Bhopal accident (1984), except a few discrete regulations, there is as yet no integrated system for assessing and managing risks arising out of these hazardous industries in India. The gravity of aspects related to the management of industrial risk still remains crucially important. In particular, there is no standard guideline on risk analysis methodology, acceptability or tolerability criteria, nor is there an accident database or a risk reduction strategy for the areas where risk levels are already high. On top of this, there are technical and legislative gaps in the institutional framework to implement any of the above mentioned issues. With the backdrop of the Bhopal gas tragedy, the objective of this paper is therefore to evaluate the effectiveness of a comprehensive risk assessment framework for the emerging economy of India, in order to control and/or to reduce the risk level that exists. In this context, regulations and policies pertaining to industrial risk assessment were reviewed. 相似文献