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Dimitris Voukantsis Harri Niska Kostas Karatzas Marina Riga Athanasios Damialis Despoina Vokou 《Atmospheric environment (Oxford, England : 1994)》2010,44(39):5101-5111
Airborne pollen have been associated with allergic symptoms in sensitized individuals, having a direct impact on the overall quality of life of a considerable fraction of the population. Therefore, forecasting elevated airborne pollen concentrations and communicating this piece of information to the public are key issues in prophylaxis and safeguarding the quality of life of the overall population. In this study, we adopt a data-oriented approach in order to develop operational forecasting models (1–7 days ahead) of daily average airborne pollen concentrations of the highly allergenic taxa: Poaceae, Oleaceae and Urticaceae. The models are developed using a representative dataset consisting of pollen and meteorological time-series recorded during the years 1987–2002, in the city of Thessaloniki, Greece. The input variables (features) of the models have been optimized by making use of genetic algorithms, whereas we evaluate the performance of three algorithms: i) multi-Layer Perceptron, ii) support vector regression and iii) regression trees originating from distinct domains of Computational Intelligence (CI), and compare the resulting models with traditional multiple linear regression models. Results show the superiority of CI methods, especially when forecasting several days ahead, compared to traditional multiple linear regression models. Furthermore, the CI models complement each other, resulting to a combined model that performs better than each one separately. The overall performance ranges, in terms of the index of agreement, from 0.85 to 0.93 clearly suggesting the potential operational use of the models. The latter ones can be utilized in provision of personalized and on-time information services, which can improve quality of life of sensitized citizens. 相似文献
23.
Agricultural wastes (AW) are often characterized by varying pH and substantial contamination potential, which are mainly related to their high organic load, thus affecting—when improperly disposed of—soils, living organisms, and water bodies. Composting of AW is the most commonly used management option and results in the production of soil improver that enhances crop growth and contributes to agricultural sustainability. This study aims to present the framework for assessing human and ecosystem risk when compost produced from AW is applied on soil. In order to develop this framework, issues such as origin, composition and pre-treatment of AW, application rates on soils, bioavailability and mobility of contaminants present in compost, exposure routes and rates as well as determination of the fate of contaminants in soil, air, and water, should be taken into consideration. 相似文献
24.
When dealing with the ecological, social and economic impacts of climate change, it is important for each country to formulate and implement mitigation and adaptation measures. In this context, the present paper examines the application of the contingent valuation method (CVM) for the monetary estimation of the Greek national mitigation and adaptation climate change costs. To this purpose, the CVM in this case study has been applied to the Greek climate change experts only as, theoretically, they represent the most informed part of Greek society in technical and economic aspects of the climate change. Therefore, the findings of this paper express strictly the opinions of the national experts and are not representative of the general population. The monetary estimates include the experts’ WTP for mitigation and adaptation measures as well as their preferences on that percentage of the national GDP that should be funding such measures at the present as well as the future time-scale. In addition, questions concerning the political and institutional climate change settings are included in the survey, providing a more comprehensive socioeconomic analysis in this particular study. 相似文献
25.
Cypermethrin is a widely used insecticide that has caused concern due to its toxicity in the aquatic environment. As with all land applied pesticides, the most significant source of water pollution is from the soil, either due to leaching or washoff. The behaviour of cypermethrin in the soil controls the likelihood of future pollution incidents, with two of the most significant processes being the formation of bound residues and microbial degradation. The formation of bound residues and mineralisation was measured in four organically managed soils from the UK. The formation of bound residues was measured using three different extraction solutions, 0.01 M CaCl2, 0.05 M HPCD and acetonitrile. Biodegradation was assessed by measurement of mineralisation of cypermethrin to CO2. The formation of bound residues varied according to extraction method, soil type and length of ageing. In two of the four soils studied, acetonitrile extractability decreased from 100% initially to 12-14% following 100 d ageing. The extent of mineralisation increased after 10-21 d ageing, reaching 33% of remaining activity in one soil, however following 100 d ageing the extent of mineralisation was significantly reduced in three out of the four soils. As with the formation of bound residues, mineralisation was impacted by soil type and length of ageing. 相似文献
26.
Kostas Vlachodimos Efimia M. Papatheodorou John Diamantopoulos Nikolaos Monokrousos 《Environmental monitoring and assessment》2013,185(8):6921-6932
Reforestation with black locust (Robinia pseudoacacia) is considered a successful technique that is often used for the reclamation of open-cast mine areas. An alternative reclamation technique could be the natural regeneration of vegetation with spontaneous grass species. In this study, we compared the concentrations of chemical and biochemical variables in soil samples taken under black locust canopy to those from sites covered by spontaneous grass vegetation (control samples) in a time sequence of spoil deposition (0–10 years), in order to assess which of the two reclamation techniques yields higher soil quality. Soil quality refers here to the ability of soils to function ecologically. This has a special interest since the main question for the restored soils is their capacity to perform a range of ecological functions under stress or disturbance. Furthermore, we aimed at identifying the effect of vegetation type on soil ecological succession. The effect of vegetation type on primary succession becomes apparent after 2 years of reclamation. R. pseudoacacia as a nitrogen-fixing plant enriched soil with organic and inorganic nitrogen and organic matter to a greater extent than the natural grasses. It also increased the amount of soil microbial biomass and the activity of alkaline phosphatase. However, the fact that black locust failed to enhance dehydrogenase activity and actually decreased the activity of urease, activities that represent specialized niche functions and therefore, are more vulnerable to stress or disturbance, suggests that the development of an indigenous grass community in combination with organic supplements might often be more appropriate for the reclamation of similar kinds of mine areas. 相似文献
27.
Basil D. Manos Jason Papathanasiou Thomas Bournaris Kostas Voudouris 《Environmental monitoring and assessment》2010,164(1-4):43-52
This paper presents a decision support system (DSS) for sustainable development and environmental protection of agricultural regions developed in the framework of the Interreg-Archimed project entitled WaterMap (development and utilization of vulnerability maps for the monitoring and management of groundwater resources in the ARCHIMED areas). Its aim is to optimize the production plan of an agricultural region taking in account the available resources, the environmental parameters, and the vulnerability map of the region. The DSS is based on an optimization multicriteria model. The spatial integration of vulnerability maps in the DSS enables regional authorities to design policies for optimal agricultural development and groundwater protection from the agricultural land uses. The DSS can further be used to simulate different scenarios and policies by the local stakeholders due to changes on different social, economic, and environmental parameters. In this way, they can achieve alternative production plans and agricultural land uses as well as to estimate economic, social, and environmental impacts of different policies. The DSS is computerized and supported by a set of relational databases. The corresponding software has been developed in a Microsoft Windows XP platform, using Microsoft Visual Basic, Microsoft Access, and the LINDO library. For demonstration reasons, the paper includes an application of the DSS in a region of Northern Greece. 相似文献
28.
Environmental education and financial support of nature conservation are considered among the primary components of the environmentalist
dimension of ecotourism. The potential of environmental education calls for enhancing visitor environmental knowledge and
prompting change of visitor behavior. The present study addressed the evaluation of the environmentalist dimension of ecotourism
in the Dadia Forest Reserve. The first objective of the research was to study the influence of variables determined prior
to the visit, namely, visitor and visit characteristics, visitor environmental information sources, visitor pro-environmental
behavior, and visitation goals, on variables determined during the visit, that is, visitor participation in and satisfaction
from ecotourism activities. The second objective was to study the effect of selected variables on visitor knowledge and behavior
intentions. Visitor participation in and satisfaction from ecotourism activities were primarily controlled by visit characteristics.
Levels of visitor knowledge were quite satisfactory; however, coherence among knowledge items was rather loose. On the other
hand, behavior intention items revealed the highest possible degree of coherence, which should be attributed to the pervasive
influence of visitor satisfaction from watching birds at the Bird Observatory within the Dadia Forest Reserve. Ecotourism
activities, during which the main part of environmental knowledge was offered, exerted no effect on visitor knowledge; all
the same, they significantly influenced visitor behavior intentions. Overall, visitor behavior intentions revealed a considerable
potential of financing environmental protection and providing voluntary work in the frame of the environmental management
of the Dadia Forest Reserve. 相似文献
29.
Jochen Harnisch Reinhard Borchers Peter Fabian Kostas Kourtidis 《Environmental science and pollution research international》1995,2(3):161-162
Carbonyl sulfide is found as a major sulfur compound in anodic gases of commercial aluminium electrolysis. Recent spectroscopic measurements on industrial aluminium smelters found typical CO/COS ratios between 80 and 200. This results in specific COS emissions of between 1 and 7 kg/t(Al) if all COS is released into the atmosphere. In 1993 aluminium production would have been responsible for between 0.02 and 0.14 Tg of COS emissions. Currently, aluminium production does not seem to influence the total atmospheric COS budget to an extent beyond its natural variability. If recent growth rates of global aluminium production are sustained, however, COS emissions would quadruple until 2030. Together with increasing aircraft emissions into the stratosphere, an increase of the sulfate background aerosol is to be expected that could significantly enhance ozone depletion. The use of inert anodes is recommended to reduce aluminium production emissions of COS and CF4, C2F6, CO2, and CO at the same time. 相似文献
30.
Kostas Bithas 《Environment, Development and Sustainability》2008,10(3):373-390
The operational designing of Environmentally Sustainable Economic Development (ESED) emerges as an urgent and demanding task.
Even though ESED has paved the way for thought-provoking and constructive scientific dialogue, appeal for designing an operational
ESED is still lagging behind the needs of contemporary societies, leaving much to be desired. With this in mind, the present
paper will aim at delineating principles for the operational application of ESED. First, the preservation of crucial properties
of environmental functions and ecosystems, emerges as a prime condition of ESED. The second condition concerns the provision
of the economic process with sufficient natural inputs; in this context, the paper intends to trace certain operational tenets
governing the use of natural resources. Finally, the appropriate institutional settings for the operational design of ESED
are traced.
Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue 相似文献