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161.
Under the Kyoto Protocol the European Union agreed to reduce emissions of greenhouse gases by 8 percent. The Burden-Sharing Agreement (BSA) redistributes the reduction target among the member states. The purpose of this paper is to evaluate the BSA. To determine if cost efficiency was considered, marginal abatement costs (MACs) are first calculated based on an estimation of the directional output distance function using country production data for 1990-2000. MACs, together with equity indicators, are then regressed on the emission change targets. The main conclusion is that both efficiency and equity were important aspects considered in the settlement. 相似文献
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164.
Annelieke Hijkoop Chiara C.M.M. Lap Moska Aliasi Eduard J.H. Mulder William L.M. Kramer Hens A.A. Brouwers Robertine van Baren Eva Pajkrt Anton H. van Kaam Caterina M. Bilardo Lourens R. Pistorius Gerard H.A. Visser René M.H. Wijnen Dick Tibboel Gwendolyn T.R. Manten Titia E. Cohen-Overbeek 《黑龙江环境通报》2019,39(13):1204-1212
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166.
Eva Emmoth Jordi Rovira Andreja Rajkovic Elena Corcuera Diego Wilches Pérez Irene Dergel Jakob R. Ottoson Frederik Widén 《Food and environmental virology》2017,9(1):20-34
Hepatitis E virus has been recognised as a food-borne virus hazard in pork products, due to its zoonotic properties. This risk can be reduced by adequate treatment of the food to inactivate food-borne viruses. We used a spectrum of viruses and bacteriophages to evaluate the effect of three food treatments: high pressure processing (HPP), lactic acid (LA) and intense light pulse (ILP) treatments. On swine liver at 400 MPa for 10 min, HPP gave log10 reductions of ≥4.2, ≥5.0 and 3.4 for feline calicivirus (FCV) 2280, FCV wildtype (wt) and murine norovirus 1 (MNV 1), respectively. Escherichia coli coliphage ?X174 displayed a lower reduction of 1.1, while Escherichia coli coliphage MS2 was unaffected. For ham at 600 MPa, the corresponding reductions were 4.1, 4.4, 2.9, 1.7 and 1.3 log10. LA treatment at 2.2 M gave log10 reductions in the viral spectrum of 0.29–2.1 for swine liver and 0.87–3.1 for ham, with ?X174 and MNV 1, respectively, as the most stable microorganisms. The ILP treatment gave log10 reductions of 1.6–2.8 for swine liver, 0.97–2.2 for ham and 1.3–2.3 for sausage, at 15–60 J cm?2, with MS2 as the most stable microorganism. The HPP treatment gave significantly (p < 0.05) greater virus reduction on swine liver than ham for the viruses at equivalent pressure/time combinations. For ILP treatment, reductions on swine liver were significantly (p < 0.05) greater than on ham for all microorganisms. The results presented here could be used in assessments of different strategies to protect consumers against virus contamination and in advice to food producers. Conservative model indicators for the pathogenic viruses could be suggested. 相似文献
167.
Endothermy and its evolution are still an unresolved issue. Here, we present a model which transforms an ectothermic amniote (ancestor) into a derived amniote (descendant) showing many characteristics seen in extant endothermic birds and mammals. Consistent with the fossil record within the ancestral lineages of birds and mammals, the model assumes that mutations in genes which get active during ontogeny and affect body growth resulted in a reduced asymptotic body size and an early growth stop of the descendant. We show that such a postulated early growth stop in the descendant simultaneously increases the growth rate and metabolic rate, and also changes six life history traits (offspring mass, annual clutch/litter mass, number of offspring per year, age and mass at which sexual maturity is reached, age at which the individual is fully grown) of the descendant compared to a similar-sized ancestor. All these changes coincide with known differences between recent ectothermic and endothermic amniotes. We also elaborate many other differences and similarities in biological characteristics supporting the early growth stop. An early stop in growth during ontogeny thus could have played a key role in the evolution of endothermy within the reptilia and therapsids. It generated variability in characteristics of ancestral ectotherms, which was subject to natural selection in the past and resulted in many adaptations linked to endothermy in today’s birds and mammals. 相似文献
168.
Peñas J Benito B Lorite J Ballesteros M Cañadas EM Martinez-Ortega M 《Environmental management》2011,48(1):168-176
Habitat fragmentation due to human activities is one of the most important causes of biodiversity loss. In Mediterranean areas
the species have co-evolved with traditional farming, which has recently been replaced for more severe and aggressive practices.
We use a methodological approach that enables the evaluation of the impact that agriculture and land use changes have for
the conservation of sensitive species. As model species, we selected Linaria nigricans, a critically endangered plant from arid and semiarid ecosystems in south-eastern Spain. A chronosequence of the evolution
of the suitable habitat for the species over more than 50 years has been reconstructed and several geometrical fragmentation
indices have been calculated. A new index called fragmentation cadence (FC) is proposed to quantify the historical evolution
of habitat fragmentation regardless of the habitat size. The application of this index has provided objective forecasting
of the changes of each remnant population of L. nigricans. The results indicate that greenhouses and construction activities (mainly for tourist purposes) exert a strong impact on
the populations of this endangered species. The habitat depletion showed peaks that constitute the destruction of 85% of the
initial area in only 20 years for some populations of L. nigricans. According to the forecast established by the model, a rapid extinction could take place and some populations may disappear
as early as the year 2030. Fragmentation-cadence analysis can help identify population units of primary concern for its conservation,
by means of the adoption of improved management and regulatory measures. 相似文献
169.
Marino E Guijarro M Hernando C Madrigal J Díez C 《Journal of environmental management》2011,92(3):1003-1011
Prescribed burning is commonly used to prevent accumulation of biomass in fire-prone shrubland in NW Spain. However, there is a lack of knowledge about the efficacy of the technique in reducing fire hazard in these ecosystems. Fire hazard in burned shrubland areas will depend on the initial capacity of woody vegetation to recover and on the fine ground fuels existing after fire. To explore the effect that time since burning has on fire hazard, experimental tests were performed with two fuel complexes (fine ground fuels and regenerated shrubs) resulting from previous prescribed burnings conducted in a gorse shrubland (Ulex europaeus L.) one, three and five years earlier. A point-ignition source was used in burning experiments to assess ignition and initial propagation success separately for each fuel complex. The effect of wind speed was also studied for shrub fuels, and several flammability parameters were measured. Results showed that both ignition and initial propagation success of fine ground fuels mainly depended on fuel depth and were independent of time since burning, although flammability parameters indicated higher fire hazard three years after burning. In contrast, time since burning increased ignition and initial propagation success of regenerated shrub fuels, as well as the flammability parameters assessed, but wind speed had no significant effect. The combination of results of fire hazard for fine ground fuels and regenerated shrubs according to the variation in relative coverage of each fuel type after prescribed burning enabled an assessment of integrated fire hazard in treated areas. The present results suggest that prescribed burning is a very effective technique to reduce fire hazard in the study area, but that fire hazard will be significantly increased by the third year after burning. These results are valuable for fire prevention and fuel management planning in gorse shrubland areas. 相似文献
170.
Julio Fuchs Lucas Piola Elio Prieto Gonz��lez Mar��a Luisa Oneto Silvana Basack Eva Kesten Norma Casab�� 《Environmental monitoring and assessment》2011,173(1-4):127-137
Contamination by 2,4,6-trinitrotoluene (TNT) is a global environmental problem at sites of former explosive production, handling, or storage, and could have deleterious consequences for human and ecological health. We investigated its sublethal effects to Eisenia fetida, using two nonspecific biomarkers. In coelomocytes of earthworms exposed 24, 48, or 72 h, we evaluated DNA damage (comet assay) and neutral red retention time (NRRT), using the filter paper contact test. Both percentage of damage (D%) and calculated damage index showed significant DNA damage at almost all concentrations, at all time points assayed. Along exposure time, two different patterns were observed. At the lower TNT concentrations (0.25?C0.5 ??g/cm2) an increased DNA migration at 48 h, with a decrease close to initial levels after 72 h exposure, was observed. This decrease could be attributed to activation of the DNA repair system. At higher concentrations (1.0?C2.0 ??g/cm2), the high DNA damage observed remained constant during the 72 h exposure, suggesting that the rate of DNA repair was not enough to compensate such damage. Analysis of NRRT results showed a significant interaction between time and treatment. After 48 h, a significant decrease was observed at 4.0 ??g/cm2. After 72 h, NRRT presented a concentration-dependent decrease, significantly different with respect to control at 0.5, 1.0, 2.0, and 4.0 ??g/cm2. The two assayed methods, performed on the same sample, showed clear responses to sublethal TNT exposure in E. fetida, providing sensitive unspecific biomarkers of cell injury and DNA damage. 相似文献