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991.
Davide Travaglini Lorenzo Fattorini Anna Barbati Francesca Bottalico Piermaria Corona Marco Ferretti Gherardo Chirici 《Environmental monitoring and assessment》2013,185(4):3255-3268
A correct characterization of the status and trend of forest condition is essential to support reporting processes at national and international level. An international forest condition monitoring has been implemented in Europe since 1987 under the auspices of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). The monitoring is based on harmonized methodologies, with individual countries being responsible for its implementation. Due to inconsistencies and problems in sampling design, however, the ICP Forests network is not able to produce reliable quantitative estimates of forest condition at European and sometimes at country level. This paper proposes (1) a set of requirements for status and change assessment and (2) a harmonized sampling strategy able to provide unbiased and consistent estimators of forest condition parameters and of their changes at both country and European level. Under the assumption that a common definition of forest holds among European countries, monitoring objectives, parameters of concern and accuracy indexes are stated. On the basis of fixed-area plot sampling performed independently in each country, an unbiased and consistent estimator of forest defoliation indexes is obtained at both country and European level, together with conservative estimators of their sampling variance and power in the detection of changes. The strategy adopts a probabilistic sampling scheme based on fixed-area plots selected by means of systematic or stratified schemes. Operative guidelines for its application are provided. 相似文献
992.
Aldona Dobrzycka-Krahel Anna Tarała Anna Chabowska 《Environmental monitoring and assessment》2013,185(6):5165-5175
Amphipod crustaceans belong to the most successful invaders of aquatic environments. The work provides information concerning the spatial and temporal scales of expansion of four alien gammarid amphipods (three of them of Ponto-Caspian and one of North American origin): Pontogammarus robustoides (G.O. Sars, 1894), Obesogammarus crassus (G.O. Sars, 1894), Dikerogammarus haemobaphes (Eichwald, 1841), and Gammarus tigrinus Sexton, 1939 in the Vistula Lagoon (VL) and the Vistula Delta (VD) in 2008–2010. The mean abundance of these gammarids in nearshore zones was 382 ind?m?2 in VL and 89 ind?m?2 in VD. Their mean biomasses were likewise greater in VL (0.91 g?m?2) than in VD (0.49 g?m?2). G. tigrinus was the most dominant species in both nearshore zones of VL and VD and attained the highest frequency in these areas. The study gives evidence of total extinction of native gammarid species. 相似文献
993.
This paper explores whether ambitions to open up the traditional Swedish model of top-down conservation methods to local influences are indicative of an actual transition in governance of Swedish national park policy (NPP), and examines whether such a shift entails an increase in local influence over local interests and needs. Methodologically, we analyse a combination of governance types and incorporate theoretical definitions of power and accountability. The establishment of new governance arrangements – where power is shared, interactions promoted and accountability is directed downwards – indicates that Sweden's NPP is undergoing a change in its mode of governance. This change also seems to include ceding some influence to local interests, and the possibility of combining conservation with the utilisation of certain natural resources. The results of our research also provide valuable insights into when the establishment of shared-governance arrangements are likely to succeed; in short, this seems more likely when there are established sectors sited in a robust legal framework and where strong international commitments potentially play a role. In conclusion, we contend that when seeking diversified governance arrangements it is not enough simply to take local practices and customs into consideration – they have to be strengthened. 相似文献
994.
Conservation scientists must meet the sometimes conflicting demands of policy and science, but not necessarily at the same time. We analysed the policy and intra-scientific orientations of research projects on effects of stump extraction on biodiversity, and found shifts over time associated with these demands. Our results indicate that uncertainties related to both factual issues and human decisions are often ignored in policy-oriented reports and syntheses, which could give misleading indications of the reliability or feasibility of any conclusions. The policy versus intra-scientific orientation of the scientific papers generated from the surveyed projects varied substantially, although we argue that in applied research, societal relevance is generally more important than intra-scientific relevance. To make conservation science more socially relevant, there is a need for giving societal relevance higher priority, paying attention to uncertainties and increasing the awareness of the value of cross-disciplinary research considering human decisions and values. 相似文献
995.
West Jordan M. Courtney Catherine A. Hamilton Anna T. Parker Britt A. Julius Susan H. Hoffman Jennie Koltes Karen H. MacGowan Petra 《Environmental management》2017,59(1):102-117
Environmental Management - The interactive and cumulative impacts of climate change on natural resources such as coral reefs present numerous challenges for conservation planning and management.... 相似文献
996.
Anna Bourliva Christophoros Christophoridis Lambrini Papadopoulou Katerina Giouri Argyrios Papadopoulos Elena Mitsika Konstantinos Fytianos 《Environmental geochemistry and health》2017,39(3):611-634
In the present study, an investigation of the mineralogy and morphology, the heavy metal content and the health risk of urban road dusts from the second largest city of Greece was conducted. For this reason road dust samples from selected sites within the city core area were collected. No differences were observed in the mineralogy of road dusts coming from different sampling sites, and they were mainly consisted of quartz and calcite, while an elevated amorphous content was detected. Morphologically road dusts presented Ca-rich, Fe-rich and silicates particles with various shapes and sizes. The mean concentrations of Cd, Cr, Cu, Mn, Ni, Pb and Zn in road dust were 1.76, 104.9, 662.3, 336.4, 89.43, 209 and 452.8 μg g?1, respectively. A series of spatial distribution patterns revealed that the hotspot areas were tended to associate with major road junctions and regions with high traffic. Combination of pollution indexes and statistical analyses (correlation analysis, cluster analysis and principal component analysis) revealed that road dusts have a severe influence by anthropogenic activities. In attempt to identify the source of metals through geostatistical and multivariate statistical analyses, it was concluded as follows: Cr, Cu, Fe and Zn mainly originated from tire/break wear and vehicle abrasions, while Cd, Mn and Pb were mainly related to fuel/oil leakage from automobiles along with oil lubricants and vehicle abrasion. Hazard quotient values for children based on total metal concentrations for the road dust ingestion route were lower than safe level (=1). However, the fact that the Hazard Index value for Pb (0.459) which is a particularly toxic metal, was close to safe level, renders essential further investigation in order to provide more reliable characterizations of potential health risks. 相似文献
997.
Residential concentrations of formaldehyde have been associated with poor respiratory health in children, where formaldehyde has been measured using stationary monitors inside homes. Although children spend most of their time indoors at home, there are few studies of children’s personal exposure to formaldehyde. The aim of this study was to investigate the relationship between personal exposure formaldehyde concentrations, microenvironmental concentrations and time weighted exposure estimates in children.Forty-one primary school children (aged between 9 and 12 years) wore a personal passive sampler over two 24 h periods in two seasons and completed 24 h daily activity diaries and a questionnaire about lifestyle and behaviour. Samplers were co located indoors at home, outdoors at centralised locations and indoors at school for the corresponding period.Personal exposure formaldehyde concentrations in this group of children were generally low with a geometric mean concentration of 9.1 ppb (range <detection limit to 27.3 ppb). There were strong correlations between personal exposure concentrations and both domestic indoor (rs = .779, p < 0.001) and time weighted estimated (rs = .802, p < 0.001) concentrations. The time weighted model did not improve the estimate of personal exposure compared with stationary indoor concentrations. Indoor air concentration measured with a single stationary monitor was a suitable surrogate for personal exposure. 相似文献
998.
Rylander L Björkdahl CM Axmon A Giwercman A Jönsson BA Lindh C Rignell-Hydbom A 《Chemosphere》2012,88(7):828-831
Background and aim
Persistent organochlorine pollutants (POPs) have in epidemiological studies been associated with health hazards. The exposure window might be crucial and it is, accordingly, important to analyze exposure concentrations in samples collected at the window of interest. This makes the use of stored blood samples extremely interesting. However, small blood volumes from stored samples in biobanks means that the researchers in epidemiological studies most often have to select a limited number of biomarkers representing the POP exposure and abstain from analyses of lipid concentrations. This raises the question of the necessity of lipid adjustment. The aim of the present study was to evaluate the correlation between fresh weight and lipid adjusted concentrations.Methods
We included data from studies were we have used the PCB congener 2,2′,4,4′,5,5′-hexachlorobiphenyl (PCB-153) as a biomarker for POP exposure and where fresh weight as well as lipid adjusted PCB-153 concentrations are known (n = 1628). The variety of the cohort members in the different studies gave us the possibility to better understand how well these measures correlate.Results
When all individuals were included in the analyses a correlation coefficient of 0.95 between fresh weight and lipid adjusted serum concentrations was obtained. Restricting the analyses to specific subgroups (based on gender, fasting status, age and BMI) gave correlation coefficients between 0.85 and 0.97.Conclusions
This study does strongly support the use of samples from biobanks in epidemiological studies for analyzing PCBs, at least regarding PCB-153, even though it is not possible to lipid adjust the results. 相似文献999.
Anna Sténs Therese Bjärstig Eva-Maria Nordström Camilla Sandström Clas Fries Johanna Johansson 《Ambio》2016,45(2):87-99
This study examines which kinds of social benefits derived from forests are emphasised by Swedish stakeholders and what governance modes and management tools they accept. Our study shows that there exists a great variety among stakeholders’ perceptions of forests’ social values, where tourism and recreation is the most common reference. There are also differences in preferred governance modes and management where biomass and bioenergy sectors advocate business as usual (i.e. framework regulations and voluntarism) and other stakeholders demand rigid tools (i.e. coercion and targeting) and improved landscape planning. This divide will have implications for future policy orientations and require deliberative policy processes and improved dialogue among stakeholders and authorities. We suggest that there is a potential for these improvements, since actors from almost all stakeholder groups support local influence on governance and management, acknowledged and maintained either by the authorities, i.e. targeting, or by the stakeholders themselves, i.e. voluntarism. 相似文献
1000.
Jean-Michel Roberge Hjalmar Laudon Christer Björkman Thomas Ranius Camilla Sandström Adam Felton Anna Sténs Annika Nordin Anders Granström Fredrik Widemo Johan Bergh Johan Sonesson Jan Stenlid Tomas Lundmark 《Ambio》2016,45(2):109-123
The rotation length is a key component of even-aged forest management systems. Using Fennoscandian forestry as a case, we review the socio-ecological implications of modifying rotation lengths relative to current practice by evaluating effects on a range of ecosystem services and on biodiversity conservation. The effects of shortening rotations on provisioning services are expected to be mostly negative to neutral (e.g. production of wood, bilberries, reindeer forage), while those of extending rotations would be more varied. Shortening rotations may help limit damage by some of today’s major damaging agents (e.g. root rot, cambium-feeding insects), but may also increase other damage types (e.g. regeneration pests) and impede climate mitigation. Supporting (water, soil nutrients) and cultural (aesthetics, cultural heritage) ecosystem services would generally be affected negatively by shortened rotations and positively by extended rotations, as would most biodiversity indicators. Several effect modifiers, such as changes to thinning regimes, could alter these patterns. 相似文献