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11.
ABSTRACT The definition and comparison of alternative water resource systems designed to meet long-range goals (say 60 years) is illustrated by a case study in Hungary. A comprehensive cost-effectiveness approach is adapted to define goals, specifications, criteria, alternatives and their capabilities. Specifications include demands given in probabilistic terms. The comparison of alternative systems is based on 12 criteria, one of which is the balance between total energy consumed and peak energy produced. Important factors involving social elements, such as flood protection and land and forest use, are described both as monetary quantities and as qualitative appreciations. Five alternative systems are defied involving flat land reservoirs, pumped storage reservoirs, interbasin transfer, and conjunctive use of surface and ground water. International cooperation is then used to rank systems and reduce the problem to a tradeoff between only two alternatives.  相似文献   
12.
The author provides an account of Hungarian regional policy and planning during the last 40 years, describing a socialist state trying to escape from a centrally planned economy. The paper discusses the consequences of the reforms and the problems of conflict resolution which resulted. The author argues that central planning will continue to be necessary in the future, and that there is a need to strengthen the co‐ordinative role of regional plans.  相似文献   
13.
In the context of international efforts to reduce the impactsof atmospheric NH3 and NH4 + (collectively, NHx), it is important to establish the link between NH3emissions and monitoring of NHx concentrations and deposition. This is equally relevant to situations where NH3emissions changes are certain (e.g. due to changed source sectoractivity), as to cases where NH3 abatement technologies havebeen implemented. Correct interpretation of adequate atmosphericmeasurements is essential, since monitoring data provide the onlymeans to evaluate trends in regional NH3 emissions.These issues have been reviewed using available measurements and modelling from nine countries. In addition to historic datasets,the analysis here considers countries where NH3 source sector activity changed (both increases and decreases) and countries where NH3 abatement policies have been implemented.In The Netherlands an `ammonia gap' was identified between the expected reduction and results of monitoring, and was attributedinitially to ineffectiveness of the abatement measures. The analysis here for a range of countries shows that atmospheric interactions complicate the expected changes, particularly sinceSO2 emissions have decreased at the same time, while at manysites the few years of available data show substantial inter-annual variation. It is concluded that networks need to beestablished that speciate between NH3 and aerosol NH4 +, in addition to providing wet deposition, and sample at sufficient sites for robust regional estimates to be established. Such measurements will be essential to monitor compliance of the international agreements on NH3 emission abatement.  相似文献   
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15.
Along term ecological research was carried out in a Hungarian oak forest, in "Bükk" National Park starting with 1972. During the faunistical studies 3,602 insect species and more than 200,000 individuals were collected. The dominant orders were Coleoptera (1,051 species), Lepidoptera (803 species), Hymenoptera (470 species) and Diptera (400 species). The relative species abundance (RSA) for all insects collected in all years of sampling period suggests a rather J shape curve than a not clear scaling property. This means that we were able to identify almost three quarters of the insect species from one ha European oak forest during the survey (from 1987 to 2003), and two third of the staphylinides expected. Considering the staphylinid fauna a total number of 160 species and 4,022 individuals were collected. The most widely occurring species in dominance order were: Ocypus biharicus, Pseudocypus mus, Atheta gagatina, Philonthus quisquiliarius, Oxypoda acuminate, Platydracus chalcocephalus, Atheta crassicomis, Latrimaeum atrocephalum, Haploglossa puncticollis, Philonthus succicola and Anotylus mutator. The pooled value of alpha diversity was 1.51. The Shannon-Weiner Index (H') was relatively high (3.29) in comparison with other studies.  相似文献   
16.
Ecotoxicological investigations focus on biological systems and their response to chemically induced stress. Experimental techniques are much more developed than deterministic dynamic modelling. In this methodological contribution a technique is presented, based on lattice theory. This technique, also calledHasse diagram technique, allows data analysis with respect to comparative evaluation. Hasse diagrams are used
  • ? to suggest a possible measure of microbial diversity,
  • ? to analyze dependencies between phospholipid fatty acids and simple geochemical parameters on an ordinal scale and
  • ? to visualise complex results of interactions of humic substances with xenobiotics.
  •   相似文献   
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    18.
    The increasing price of energy, the security of supply, the reduction of green house gases, and the scarcity of oil and gas urge the use of more and more renewable energy. An important renewable energy source is the biomass which can be applied for heat, electricity, and transportation fuel production. The heat and electricity production are the so called “direct utilisation” alternatives and the transportation fuel production alternatives are the “indirect utilisation” alternatives of biomass energy. If efficient land use is considered, the alternatives can be compared on the basis of the utilisable energy produced from the biomass per hectare. It is shown that the bioethanol production from corn has about 89–99% less energy production capability than that of the direct utilisation alternatives. The cellulosic type bioethanol production technologies, since these partially directly utilise the biomass energy, have better energy utilisation potential, that is about 40–50% of direct alternatives.  相似文献   
    19.
    This article describes the development of the Ammonia Injection Technology (AIT), a technology for the simultaneous control of the emissions of PCDD/PCDF (polychlorinated p-dibenzodioxins and polychlorinated dibenzofurans), HCI, SO2 and NOX from municipal solid waste incinerators. It briefly reviews the theoretical basis of the technology and the bench-scale and pilot-scale experiments. It describes the results of the pilot-scale experiment in detail and reports on the finding that the formation of PCDD and PCOF takes place in different regions of the boiler system. Finally, a concept is introduced for the treatment of emission control residues which could lead to the recovery of chlorine from waste products and its “recycle” to the chlorine manufacturing process (“closed chlorine life cycle“ concept).  相似文献   
    20.
    The peri-urban soils of Huelva, one of the first industrial cities in Spain, are subject to severe pollution problems primarily due to past poor management of industrial wastes and effluents. In this study, soil cores were collected in seven sites potentially contaminated with toxic chemicals arising from multiple anthropogenic sources, in order to identify trace elements of concern and to assess human health risks associated with them. In most soil core samples, total concentrations of As (up to 4,390 mg kg−1), Cd (up to 12.9 mg kg−1), Cu (up to 3,162 mg kg−1), Pb (up to 6,385 mg kg−1), Sb (up to 589 mg kg−1) and Zn (up to 4,874 mg kg−1) were by more than one order of magnitude greater than the site-specific reference levels calculated on the basis of regional soil geochemical baselines. These chemicals are transferred from the hazardous wastes, mainly crude pyrite and roasted pyrite cinders, to the surrounding soils by acid drainage and atmospheric deposition of wind-blown dust. Locally, elevated concentrations of U (up to 96.3 mg kg−1) were detected in soils affected by releases of radionuclides from phosphogypsum wastes. The results of the human health risk-based assessment for the hypothetical exposure of an industrial worker to the surface soils indicate that, in four of the seven sites monitored, cancer risk due to As (up to 4.4 × 10−5) is slightly above the target health risk limit adopted by the Spanish legislation (1 × 10−5). The cumulative non-carcinogenic hazard index ranged from 2.0 to 12.2 indicating that there is also a concern for chronic toxic effects from dermal contact with soil.  相似文献   
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