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Pertti Ranta § Antti Tanskanen † Jari Niemelä and Arto Kurtto‡ 《Conservation biology》1999,13(6):1293-1300
Abstract: The occurrence of vascular plants was surveyed on 207 islands (size range 0.01–390.2 ha, number of plant species 1–449) offshore from the city of Helsinki in the Baltic Sea to examine the conservation value of these islands. We calculated a rarity score for each species (1/number of islands occupied by the species) and a biodiversity score for each island (sum of the rarity scores of each species present on the island). Positive correlations between species number and biodiversity score (r s = 0.97, p < 0.001) and between biodiversity score and island area (r s = 0.87, p < 0.001) indicated that these parameters are heavily dependent on island size. With the goal of including at least one occurrence (island) of all plant species, an iterative selection algorithm chose a set of 41 islands whose average size (29.3 ha) was four times the average size of all existing islands (7.0 ha). Strong nestedness ( N < 54) explains the concentration of plant species diversity on large islands. An operational strategy for selection of sites for protection is to complement the set produced by a selection algorithm with target species not yet included (e.g., endangered species with several occurrences). Comprehensive mapping and analysis of a taxonomic group will help integrate conservation biology into land-use planning and increase the quality of the networks of protected areas. 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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An experiment combining the use of two ecosystem models was conducted to search for effective protection strategies for the Gulf of Finland (Baltic Sea). Reference and scenario simulations were first run with a one-dimensional (1D) model for seven main basins of the entire Baltic Sea until steady state was achieved. The obtained basinwise distributions of inorganic nitrogen (N) and phosphorus (P), as well as sediment labile P, were then used to initiate 5-y simulations with a three-dimensional (3D) ecosystem model. The results suggest that relatively small local load reductions (the "Finland" scenario) would improve only the state of adjacent coastal waters significantly. This would be the case, even for runs covering several decades, which clearly exceed the residence times of nutrients in the Gulf of Finland. A significant decrease from a substantial loading source to the Gulf (the "St. Petersburg" scenario) would decrease cyanobacterial biomasses in the entire Gulf of Finland and also immediately outside it. A reduction in the current Polish nutrient loads would improve the situation in the whole Baltic Proper and cause an extensive decline in cyanobacterial biomasses in the Gulf of Finland, as well. However, it would take several decades until the improvement caused by reducing loads in the "Poland" scenario is seen, while in the "St. Petersburg" scenario the corresponding time lag would only be a few years. Our results suggest that the common water protection policy in the Baltic Sea region should have the largest nutrient sources as its primary target, regardless of their location and country. 相似文献
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The great majority of genetic defects underlying steroid 21-hydroxylase deficiency appear to result from intergenic recombinations between the homologous CYP21 and CYP21P genes. For a minority, novel sporadic point mutations have been detected. De novo mutations in CYP21 have also been reported, but only a few studies have systematically screened their occurrence. We here describe a population-based patient sample in order to estimate the rate of single-family (i.e. sporadic) and de novo germline mutations in the human CYP21 locus. Among 76 Finnish families were observed three single-family mutations and two de novo mutations in CYP21. The rates obtained, ∼5% and ∼2% for novel and de novo mutations, respectively, indicate that they are not rare and that their occurrence should not be ignored in genetic diagnostics of this disorder. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
16.
Genetic Diversity, Population Size, and Fitness in Central and Peripheral Populations of a Rare Plant Lychnis viscaria 总被引:1,自引:0,他引:1
Abstract: Genetic diversity is expected to decrease in small and isolated populations as a consequence of bottlenecks, founder effects, inbreeding, and genetic drift. The genetics and ecology of the rare perennial plant Lychnis viscaria (Caryophyllaceae) were studied in both peripheral and central populations within its distribution area. We aimed to investigate the overall level of genetic diversity, its spatial distribution, and possible differences between peripheral and central populations by examining several populations with electrophoresis. Our results showed that the level of genetic diversity varied substantially among populations ( H exp = 0.000–0.116) and that the total level of genetic diversity (mean H exp = 0.056) was low compared to that of other species with similar life-history attributes. The peripheral populations of L. viscaria had less genetic variation (mean H exp = 0.034) than the central ones (0.114). Analysis of genetic structure suggested limited gene flow (mean F ST = 0.430) and high differentiation among populations, emphasizing the role of genetic drift ( N e m = 0.33). Isolation was even higher than expected based on the physical distance among populations. We also focused on the association between population size and genetic diversity and possible effects on fitness of these factors. Population size was positively correlated with genetic diversity. Population size and genetic diversity, however, were not associated with fitness components such as germination rate, seedling mass, or seed yield. There were no differences in the measured fitness components between peripheral and central populations. Even though small and peripheral populations had lower levels of genetic variation, they were as viable as larger populations, which emphasizes their potential value for conservation. 相似文献
17.
Roots Ott Roose Antti Kull Ain Holoubek Ivan Cupr Pavel Klanova Jana 《Environmental science and pollution research international》2010,17(3):740-749
Background, aim, and scope
Passive air sampling survey of the Central and Eastern Europe was initiated in 2006. This paper presents data on toxic organic compounds such as polychlorinated biphenyls (PCB 28, 52, 101, 118, 153, 138, and 180), hexachlorobenzene (HCB), pentachlorobenzene (PeCB), hexachlorocyclohexane compounds (α-HCH, β-HCH,γ-HCH, δ-HCH), and dichloro-diphenyl-trichloroethane (DDT) compounds (p,p′DDE, p,p′DDD, p,p′DDT, o,p′DDE, o,p′DDD, and o,p′DDT) determined in ambient air and soil samples collected at Estonian monitoring stations. 相似文献18.
19.
Kari Rasilainen Juhani Suksi Timo Ruskeeniemi Petteri Pitknen Antti Poteri 《Journal of contaminant hydrology》2003,61(1-4):235
Uranium release observed in a rock matrix around water-carrying fractures was studied using U-series disequilibrium (USD) modelling and mass balance calculations. Several release scenarios were tested, with specific attention to the glacial aspects. The release appears to have occurred in two or three violent episodes during the last 300 ky. A release after the last glaciation can be excluded on mass flow grounds. Continuous release for more than 300 ky can be excluded on radioactive disequilibrium grounds. Repeated inflows of oxic glacial meltwater seem to have triggered the release episodes. 相似文献
20.
ABSTRACTPrevious research has suggested that corporatist polities tend to enact more ambitious environmental policies than others. Here it is argued that the macro concept of corporatism can be dissected into three components: inclusiveness, consensualism and strength of tripartite organisations. These components of corporatism can be measured at the meso-level of policy networks. It is proposed that inclusiveness and consensualism are related to ambitious climate policy but exclusive tripartite coalitions can be detrimental for the ambitiousness of climate policy. This argument is backed by evidence from policy network surveys in two similar corporatist countries where climate change policies diverge: Sweden, where policies are ambitious, and Finland, where they are less so. It is found that in Sweden the climate change policy network is more consensual and slightly more inclusive, while in Finland tripartite organisations play a strong role. 相似文献