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Pitkänen T Karinen P Miettinen IT Lettojärvi H Heikkilä A Maunula R Aula V Kuronen H Vepsäläinen A Nousiainen LL Pelkonen S Heinonen-Tanski H 《Ambio》2011,40(4):377-390
The raw water quality and associations between the factors considered as threats to water safety were studied in 20 groundwater supplies in central Finland in 2002-2004. Faecal contaminations indicated by the appearance of Escherichia coli or intestinal enterococci were present in five small community water supplies, all these managed by local water cooperatives. Elevated concentrations of nutrients in raw water were linked with the presence of faecal bacteria. The presence of on-site technical hazards to water safety, such as inadequate well construction and maintenance enabling surface water to enter into the well and the insufficient depth of protective soil layers above the groundwater table, showed the vulnerability of the quality of groundwater used for drinking purposes. To minimize the risk of waterborne illnesses, the vulnerable water supplies need to be identified and appropriate prevention measures such as disinfection should be applied. 相似文献
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Sanna Syri Antti Lehtil Tommi Ekholm Ilkka Savolainen Hannele Holttinen Esa Peltola 《International Journal of Greenhouse Gas Control》2008,2(2):274-285
The achievement possibilities of the EU 2 °C climate target have been assessed with the ETSAP TIAM global energy systems model. Cost-effective global and regional mitigation scenarios of carbon dioxide, methane, nitrous oxide and F-gases were calculated with alternative assumptions on emissions trading. In the mitigation scenarios, an 85% reduction in CO2 emissions is needed from the baseline, and very significant changes in the energy system towards emission-free sources take place during this century. The largest new technology groups are carbon-capture and storage (CCS), nuclear power, wind power, advanced bioenergy technologies and energy efficiency measures. CCS technologies contributed a 5.5-Pg CO2 annual emission reduction by 2050 and 12 Pg CO2 reduction by 2100. Also large-scale forestation measures were found cost-efficient. Forestation measures reached their maximum impact of 7.7 Pg CO2 annual emission reduction in 2080. The effects of uncertainties in the climate sensitivity have been analysed with stochastic scenarios. 相似文献
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Kim Pingoud Tommi Ekholm Ilkka Savolainen 《Mitigation and Adaptation Strategies for Global Change》2012,17(4):369-386
A method is presented for estimating the global warming impact of forest biomass life cycles with respect to their functionally
equivalent alternatives based on fossil fuels and non-renewable material sources. In the method, absolute global warming potentials
(AGWP) of both the temporary carbon (C) debt of forest biomass stock and the C credit of the biomass use cycle displacing
the fossil and non-renewable alternative are estimated as a function of the time frame of climate change mitigation. Dimensionless
global warming potential (GWP) factors, GWPbio and GWPbiouse, are derived. As numerical examples, 1) bioenergy from boreal forest harvest residues to displace fossil fuels and 2) the
use of wood for material substitution are considered. The GWP-based indicator leads to longer payback times, i.e. the time
frame needed for the biomass option to be superior to its fossil-based alternative, than when just the cumulative balance
of biogenic and fossil C stocks is considered. The warming payback time increases substantially with the residue diameter
and low displacement factor (DF) of fossil C emissions. For the 35-cm stumps, the payback time appears to be more than 100 years
in the climate conditions of Southern Finland when DF is lower than 0.5 in instant use and lower than 0.6 in continuous stump
use. Wood use for construction appears to be more beneficial because, in addition to displaced emissions due to by-product
bioenergy and material substitution, a significant part of round wood is sequestered into wood products for a long period,
and even a zero payback time would be attainable with reasonable DFs. 相似文献
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Tuija Sulisalo David Sillence Meredith Wilson Markku Ryynänen Ilkka Kaitila 《黑龙江环境通报》1995,15(2):135-140
Cartilage-hair hypoplasia (CHH) is an autosomal recessive disorder resulting in short stature and hypoplasia of hair. Associated features include impaired T-cell-mediated immunity, deficient erythropoiesis, gastrointestinal dysfunction, and an increased risk of malignancies. As the condition may, in some cases, be severe or even fatal during childhood, families with a previous history of CHH may wish to have prenatal diagnosis. We have previously assigned the gene for CHH to the proximal 9p by linkage analysis using several polymorphic DNA markers. Here we report the prenatal testing for CHH in three Finnish and one Australian family using three DNA markers closely linked to the CHH gene. In three cases a fetus unaffected with CHH was predicted at the probability level of more than 94 per cent. In one case, an affected fetus was predicted. The results were in concordance with ultrasonography performed for all fetuses. The three children born to date were unaffected as predicted. The DNA marker-based analysis thus provides a useful method for early prenatal testing for CHH. 相似文献
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The Quantitative Incidence Function Model and Persistence of an Endangered Butterfly Metapopulation 总被引:9,自引:0,他引:9
The incidence function model is derived from a linear first-order Markov chain of the presence or absence of a species in a habitat patch. The model can be parameterized with "snapshot" presence/absence data from a patch network. Using the estimated parameter values the Markov chain can be iterated in the same or in some other patch network to generate quantitative predictions about transient metapopulation dynamics and the stochastic steady state. We tested the ability of the incidence function model to predict patch occupancy using extensive data on an endangered butterfly, the Glanville fritillary ( Melitaea cinxia ) Parameter values were estimated with data collected from a 50-patch network in 1991. In 1993 we surveyed the entire geographic range of the species in Finland, within an area of 50 × 70 km2 , with 1502 habitat patches (dry meadows) of which 536 were occupied. Model predictions were generated for the 1502 patches and were compared with the observed pattern of occupancy in 1993. The model predicted patch occupancy well in more than half of the study area, but prediction was poor for one quarter of the area, probably because of regional variation in habitat quality and because metapopulations may have been perturbed away from the steady state. The incidence function model provides a practical tool for making quantitative predictions about metapopulation dynamics of species living in fragmented landscapes. 相似文献
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Microbiological contamination of groundwater supplies causes waterborne outbreaks worldwide. In this study, two waterborne outbreaks related to microbiological contamination of groundwater supplies are described. Analyses of pathogenic human enteric viruses (noroviruses and adenoviruses), fecal bacteria (Campylobacter spp. and Salmonella spp.), and indicator microbes (E. coli, coliform bacteria, intestinal enterococci, Clostridium perfringens, heterotrophic plate count, somatic and F-specific coliphages) were conducted in order to reveal the cause of the outbreaks and to examine the effectiveness of the implemented management measures. Moreover, the long-term persistence of noro- and adenovirus genomes was investigated. Noroviruses were detected in water samples from both outbreaks after the intrusion of wastewater into the drinking water sources. In the outbreak I, the removal efficiency of norovirus genome (3.0 log10 removal) in the sand filter of onsite wastewater treatment system (OWTS) and during the transport through the soil into the groundwater well was lower than the removal efficiencies of E. coli, coliform bacteria, intestinal enterococci, and spores of C. perfringens (6.2, 6.0, > 5.9, and > 4.8 log10 removals, respectively). In the outbreak II, cleaning of massively contaminated groundwater well and drinking water distribution network proved challenging, and noro- and adenovirus genomes were detected up to 3 months (108 days). The long-term persistence study showed that noro- and adenovirus genomes can remain detectable in the contaminated water samples up to 1277 and 1343 days, respectively. This study highlights the transport and survival properties of enteric viruses in the environment explaining their potency to cause waterborne outbreaks. 相似文献
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Research on group living in animals is concentrated on highly social species, but studying less social species may hint at the factors possibly leading to the evolution of increased sociality. Thermoregulation is often thought to explain communal nesting in solitarily breeding mammals but also other factors may be involved. For example, it is observed that even solitary species may have cryptic kin cooperation. We studied factors affecting communal nesting in the Siberian flying squirrel. Flying squirrels breed solitarily but, similar to most other rodents, adults may sometimes huddle in groups. Communal nesting in flying squirrels was most frequent during winter and autumn, but also occurred during other seasons. This pattern was explained by the breeding season, which took place in the spring–summer, when communal nesting was less common. Neither monthly temperature, after accounting for breeding season, nor daily temperatures in winter explained communal nesting. Group size was small, two to three individuals. In most cases the group was a pair consisting of unrelated male and female, possibly indicating that group formation was related to mating behavior. This study contributes to the understanding of mammalian group formation in two major ways. First, our study contributes to the understanding of the role of relatedness in rodent group formation, demonstrating a case where close relatedness is not related to group formation. Second, our study indicates that in a solitarily breeding, rodent huddling may be more driven by other factors than temperature. 相似文献
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Jukka Sinisalo Ilkka Savolainen 《Journal of the Air & Waste Management Association (1995)》2013,63(7):806-810
Abstract The possibility of decreasing the Nordic countries’ contribution to global warming in the future is examined. Anthropogenic carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) emissions are considered. Global average radiative forcing is used as a measure of the greenhouse impact caused by the emissions. Past emissions are included in the study because they have impact far into the future. The calculation method utilized in this study can be applied to any other country. Two hypothetical future emission development cases are presented, and the radiative forcing caused by them is calculated. In the higher emission (case A) CO2 emissions remain above current level, while N2O and CH4 emissions decrease. In the lower emission (case B) the emissions decrease to about one–tenth of the current emissions by the year 2100. Only if very strict emission reductions (case B) take place will the greenhouse impact of the Nordic countries return to current levels during next century. Likewise, the per capita radiative forcing of Nordic countries will remain above global average unless the emissions decrease drastically (case B) and the current population levels are used in per capita calculation. 相似文献