波罗的海蓝藻赤潮的历史

波罗的海所发生的赤湖,主要是由Nodudaria spupmigena和Aphanizomenon sp.这两种蓝藻形成的.有关这些赤潮的长期变化记录可以从过去(1887～1938年)和现代(1974～1998年)出版的浮游植物数据记录中找到.通过各种不同的收集、分析方法已经得到了大量的数据,为了提高这些数据的可比性,人们正在不断地尝试老的、新的采样方式与固定方法.l00多年前,浮游生物就做为鱼类的食物来源而引起了人们的兴趣;富营养化问题主要出现在南部的礁湖(haffs)以及大城市附近的海边水ro域.二战前,很少有关于开阔海域赤潮的报道.在过去的营养环境中,Nodudaria spupmlgena和Aphanizomenon sp.的数量还很少,从l 887～1938年的137个夏季采样中表明它们的丰度还没有达到过最高峰.在现在的营养环境中,高丰度是非常普遍的,这两个物种的数目范围相对于过去的营养环境来说有了明显的增长.自20世纪60年代以来,蓝藻赤潮在波罗的海本体与芬兰湾的开阔海域是非常常见的,这表明了营养物已经高度丰富.     

Inbreeding and competitive ability in the common shrew (<Emphasis Type="Italic">Sorex araneus</Emphasis>)

Common shrews (Sorex araneus) maintain a foraging territory for most of their immature life. Possessing a high-quality territory is vital for overwinter survival in the harsh boreal climate, and hence, competitive ability in territorial disputes is expected to be an important component of individual fitness. To test possible association between individual inbreeding and fitness, we used neutral arena trials to assess the competitive performance of young common shrews. The experiment involved pairs of individuals originating from small island populations, where breeding must often occur between related individuals, and from large outbred mainland populations. The percentage of neutral arena tests that an individual won was highly significantly explained by internal relatedness, a surrogate measure of individual inbreeding, measured using ten microsatellite markers. Body size, sex, learning, and population type (mainland vs island) made no significant contributions. Even a low level of individual inbreeding may lead to significant adverse consequences in multiple territorial contests, which may represent a significant cause of inbreeding depression in many wild vertebrate populations.     

Grazing and abandonment determine different tree dynamics in wood-pastures

Wood-pastures are threatened biotopes in which trees and livestock grazing maintain high conservation values. However, browsing may threaten tree regeneration, whereas abandonment leads to tree encroachment. We studied the regeneration of trees in a grazed and abandoned boreal wood-pastures. In grazed sites, the density of young spruces (Picea abies) was high, while the density of young birches (Betula spp.) was very low. Sprucification can be prevented only by removing spruces. The number of young birches and pines (Pinus sylvestris) was correlated with the number of junipers (Juniperus communis), probably because thorny junipers protect palatable seedlings from browsing. In abandoned sites, deciduous trees and spruces regenerated abundantly. In the long term, both grazing and abandonment lead to changes in tree species compositions and low diversity wood-pastures. Landscape scale planning and disturbance dynamics are needed for the creation of new wood-pastures and the maintenance of all pasture types within the landscape.

     

Fluxes of N2O, CH4 and CO2 in a meadow ecosystem exposed to elevated ozone and carbon dioxide for three years

Open-top chambers (OTCs) were used to evaluate the effects of moderately elevated O3 (40-50 ppb) and CO2 (+100 ppm) and their combination on N2O, CH4 and CO2 fluxes from ground-planted meadow mesocosms. Bimonthly measurements in 2002-2004 showed that the daily fluxes of N2O, CH4 and CO2 reacted mainly to elevated O3, while the fluxes of CO2 also responded to elevated CO2. However, the fluxes did not show any marked response when elevated O3 and CO2 were combined. N2O and CO2 emissions were best explained by soil water content and air and soil temperatures, and they were not clearly associated with potential nitrification and denitrification. Our results suggest that the increasing O3 and/or CO2 concentrations may affect the N2O, CH4 and CO2 fluxes from the soil, but longer study periods are needed to verify the actual consequences of climate change for greenhouse gas emissions.     

Governance experiments in climate action: empirical findings from the 28 European Union countries

Climate targets call for novel policy measures to facilitate widespread adoption of low-carbon solutions and innovations. The literature on socio-technical systems argues that experimentation has a prominent role in enabling sustainability transition. Experiments represent ways of testing new ideas and methods across a wide range of policy fields. Governance experiments in particular can support accelerated diffusion of new solutions, because they integrate policy with innovations. Here, types of success factors in the implementation of governance experiments to mitigate climate change are examined. Statistical analysis of sustainability innovations in the 28 European Union countries indicates that the types of success factors in governance experiments differ from those of product and social experiments. Governance experimentation is more positioned within socio-technical regimes than in strategic niches. These results suggest that governance experiments may indeed provide new transition opportunities towards low-carbon societies.     

Effect of birch (Betula spp.) and associated rhizoidal bacteria on the degradation of soil polyaromatic hydrocarbons, PAH-induced changes in birch proteome and bacterial community

Two birch clones originating from metal-contaminated sites were exposed for 3 months to soils (sand-peat ratio 1:1 or 4:1) spiked with a mixture of polyaromatic hydrocarbons (PAHs; anthracene, fluoranthene, phenanthrene, pyrene). PAH degradation differed between the two birch clones and also by the soil type. The statistically most significant elimination (p ≤ 0.01), i.e. 88% of total PAHs, was observed in the more sandy soil planted with birch, the clearest positive effect being found with Betula pubescens clone on phenanthrene. PAHs and soil composition had rather small effects on birch protein complement. Three proteins with clonal differences were identified: ferritin-like protein, auxin-induced protein and peroxidase. Differences in planted and non-planted soils were detected in bacterial communities by 16S rRNA T-RFLP, and the overall bacterial community structures were diverse. Even though both represent complex systems, trees and rhizoidal microbes in combination can provide interesting possibilities for bioremediation of PAH-polluted soils.     

Removal by sorption and in situ biodegradation of oil spills limits damage to marine biota: a laboratory simulation

This study examined the efficiency of cotton grass fibers in removing diesel oil from the surface of water in conditions prevailing in the Baltic Sea. The effect of low temperature, salinity, and bacterial amendments were tested in laboratory-scale set-ups, whereas 600-L mesocosms filled with Baltic Sea water were used for testing the effects of diesel oil and rapid removal of the oil on microorganisms, phytoplankton, and mussels. Cotton grass proved to be an excellent sorbent for diesel oil from the water surface at a low temperature. Inoculation with diesel-enriched microorganisms enhanced degradation of oil significantly in laboratory-scale experiments. In mesocosm experiments, the addition of diesel oil (0.66 mg L(-1), 0.533 L m(-2)) to the basins resulted in higher microbial density than in all other basins, including inoculated ones, suggesting that the Baltic Sea contains indigenous hydrocarbon degraders. The removal of oil with cotton grass significantly improved the survival of mussels in the mesocosm tests: 100% mortality in diesel basins versus 0% mortality in basins with cotton grass, respectively. However, the surviving mussels suffered from histopathological changes such as inflammatory responses, degenerations, and cell death. The observed rescuing effect was observable even when the cotton grass-bound oil was left in the water. The results underline the importance of rapid action in limiting damage caused by oil spills.     

Bacterial diversity and function in the Baltic Sea with an emphasis on cyanobacteria

In this article we summarize the current knowledge of Baltic Sea cyanobacteria, focusing on diversity, toxicity, and nitrogen fixation in the filamentous heterocystous taxa. We also review the recent results of our microbial diversity studies in planktonic and benthic habitats in the Baltic Sea. Based on molecular analyses, we have improved the understanding of cyanobacterial population structure by assessing genetic diversity within species that are morphologically inseparable. Moreover, we have studied microbial functions such as toxin production and nitrogen fixation in situ under different environmental conditions. Phosphorus limitation of bloom-forming, nitrogen-fixing cyanobacteria was clearly verified, emphasizing the importance of continuous efforts to reduce this element in the Baltic Sea. We have designed a rapid and reliable detection method for the toxic cyanobacterium Nodularia spumigena, which can be used to study bloom formation of this important toxin producer.     

Sex segregation of work in Finland and the quality of women's work

The Finnish labor market is sharply segregated by sex. This is a statistically well-documented fact and holds true for all Western European market economies. The aim of this article was to find out whether women profit (regarding the quality of their work) from performing the same sort of work as men. The qualitative aspects of work were the following: autonomy at work; lack of routinization of work; the compulsory rhythm of work; and the demands for social skills. We also analyzed monthly pay and its variation according to functional segregation of work. The empirical data came from the Finnish Study on Working Conditions (1984) which is a representative sample of the Finnish wage-earning population with 4502 persons of whom 48 per cent were women and 52 per cent men. Our results indicate that women often profit from the fact that they perform the same sort of work as men. This profit was more apparent for white-collar than for blue-collar women. For men the effects of segregation on job characteristics were the opposite. They often profit from sex segregated work. Social status played a major role regarding the qualitative aspects of work.