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21.
Wolfgang Cramer Uta Fritsch Rik Leemans Sabine Lütkemeier Dagmar Schröter Allan Watt 《Regional Environmental Change》2008,8(3):125-134
Biodiversity is essential for multiple aspects of human life and well-being, but many current assessments of the functioning
of biodiversity and ecosystems, understanding of risks posed by environmental change and the best practice of their management
of ecosystems are lacking a unified scientific and conceptual basis. Methods such as scenario analysis, and terms such as
ecosystem services, are widely used, but their meaning is understood in many different ways depending on context, user needs
and experience of researchers. In order to advance the conceptual basis for ecosystem analysis and management in a rapidly
changing world, as well as the ability of young scientists to reflect upon these concepts, we have organised five 2-week-long
summer schools in Peyresq, a remote village in the Southern French Alps. In total 173 participants have worked intensively
with 69 experienced researchers and a team of conveners and tutors in order to discuss a broad range of views on topics on
ecosystem analysis and functioning. Topics ranged from conditions of and threats to various ecosystems due to environmental
change, models and scenarios for assessment, stakeholder perceptions and needs for information, to the social and economic
contexts for biodiversity. We report our experience from these schools, present the training concept which has emerged from
them and suggest lines of further development.
相似文献
Wolfgang CramerEmail: |
22.
Seyedehsan Hosseini Manish Shrivastava Li Qi David R. Weise David R. Cocker John W. Miller 《Journal of the Air & Waste Management Association (1995)》2014,64(6):690-703
Low-density polyethylene (LDPE) plastic is used to keep piled debris from silvicultural activities—activities associated with development and care of forests—dry to enable efficient disposal by burning. The effects of inclusion of LDPE in this manner on smoke emissions are not well known. In a combustion laboratory experiment, 2-kg mixtures of LDPE and manzanita (Arctostaphylos sp.) wood containing 0, 0.25, and 2.5% LDPE by mass were burned. Gaseous and particulate emissions were sampled in real time during the entire flaming, mixed combustion phase—when the flaming and smoldering phases are present at the same time—and during a portion of the smoldering phase. Analysis of variance was used to test significance of modified combustion efficiency (MCE)—the ratio of concentrations of fire-integrated excess CO2 to CO2 plus CO—and LDPE content on measured individual compounds. MCE ranged between 0.983 and 0.993, indicating that combustion was primarily flaming; MCE was seldom significant as a covariate. Of the 195 compounds identified in the smoke emissions, only the emission factor (EF) of 3M-octane showed an increase with increasing LDPE content. Inclusion of LDPE had an effect on EFs of pyrene and fluoranthene, but no statistical evidence of a linear trend was found. Particulate emission factors showed a marginally significant linear relationship with MCE (0.05 < P-value < 0.10). Based on the results of the current and previous studies and literature reviews, the inclusion of small mass proportions of LDPE in piled silvicultural debris does not appear to change the emissions produced when low-moisture-content wood is burned. In general, combustion of wet piles results in lower MCEs and consequently higher levels of emissions.
Implications:Current air quality regulations permit the use of burning to dispose of silvicultural piles; however, inclusion of low-density polyethyelene (LDPE) plastic in silvicultural piles can result in a designation of the pile as waste. Waste burning is not permitted in many areas, and there is also concern that inclusion of LDPE leads to toxic air emissions. 相似文献
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A stakeholder dialogue on European vulnerability 总被引:1,自引:1,他引:0
Anne C. de la Vega-Leinert Dagmar Schröter Rik Leemans Uta Fritsch Jacomijn Pluimers 《Regional Environmental Change》2008,8(3):109-124
A stakeholder dialogue was embedded in the ATEAM project to facilitate the development and dissemination of its European-wide
vulnerability assessment of global change impacts. Participating stakeholders were primarily ecosystem managers and policy
advisers interested in potential impacts on ‘Agriculture’, ‘Forestry’, ‘Water’, ‘Carbon storage’, ‘Biodiversity’ and ‘Mountain
environments’ sectors. First, stakeholder dialogue approaches to integrated assessment are introduced. Methodological considerations
on stakeholder selection and dialogue implementation and evaluation follow. The dialogue content and process are evaluated
from the perspectives of stakeholders and scientists. Its usefulness in the research process and the relevance of outcomes
for stakeholders are particularly considered. The challenging compromises required to perform innovative research, which seeks
to achieve both peer scientific credibility and societal relevance, are emphasized. Effective stakeholder dialogues play a
substantial role in raising the visibility and meaningfulness of vulnerability assessments as critical means to improve awareness
on global change and its potential worrying impacts on society. They further provide scientists with critical information
on ecosystem management and sectoral adaptive capacity. These processes of mutual learning and knowledge exchange moreover
foster a better understanding of the potential and limits of global change modelling and vulnerability assessment for policy
and ecosystem management.
相似文献
Anne C. de la Vega-LeinertEmail: |
26.
Periodical cicadas in the genus Magicicada have an unusual life history that includes an exceptionally long life cycle and a massive, synchronized emergence. Distributions in woodland habitat are extremely patchy, and an unresolved problem is how the patchiness is generated and maintained. We undertook a study in Princeton, New Jersey, USA, to determine if habitat factors such as tree height, distance to the nearest neighbor, and amount of foliage influence distributions of nymphal emergences, centers of chorusing aggregations, and oviposition sites. Emerging nymphs were counted, chorus centers were identified by measuring decibel levels of their songs, and oviposition was estimated from the foliage "flags" that are produced by trees in response to the damage caused by egg-laying. All three distributions were mapped on 50 trees in a human-managed area of 75 x 130 m. We were unable to identify habitat features that were associated with the distribution of emergences, except that tulip trees (Liriodendron) had significantly fewer emergences than two other genera, ash (Fraxinus) and beech (Fagus). Using multiple linear regression analysis, we found that the distribution of emergences was the best predictor of the distribution of chorus centers and oviposition sites. In an analysis of ash trees alone, tree height and spacing, in addition to cicada emergences, predicted chorus centers and oviposition incidence. Thus the distribution of the offspring generation (oviposition) is shown to be similar to the parental generation (emergence). We suggest that their stability is maintained across generations by extremely low dispersal and mutual attraction. Aggregations may be thought of as self-perpetuating, randomly distributed assemblages, initially established through the interaction of factors, including successful exploitation of underground resources, and avoidance of fungal disease and aboveground predation in the development of high-density mating aggregations. 相似文献
27.
Olaf Wappelhorst Siegfried Korhammer Uta -Susanne Leffler Bernd Markert 《Environmental Sciences Europe》2000,12(4):191-200
This article describes a biomonitoring using mosses in order to determine the amount and distribution of the atmospheric deposition of 37 elements in the European region of the Neisse river following the political and economic changes. These results are compared with the findings in other regions. Additionally, the accumulation characteristics ofPleurozium schreberi andPolytrichum formosum, the two moss species used in the study, were compared with one another. Until the beginning of the 1990s, this region was part of the socalled “black triangle”, an area characterised by extremely high atmospheric dust pollution. Through the closing of numerous factories, the equipment of power plants with filters, and the decreasing importance of brown coal as a source of household heating, the situation has changed considerably. Today, the pollution levels in the European region of the Neisse river are comparable with those in the western part of Germany. Higher levels were only determined for Fe and Ti, which can be attributed to the broader usage of brown coal as a source of energy. In the area around Katowice, Poland, the levels of certain elements were found to be more than ten times higher than in the European region of the Neisse. These highly elevated levels of atmospheric contamination in the industrial district of Upper Silesia indicate that action is urgently needed. 相似文献
28.
Millicent S. Ficken Steve R. Witkin Charles M. Weise 《Behavioral ecology and sociobiology》1981,8(4):245-249
Summary One color-banded black-capped chickadee flock was studied intensively at a winter feeder in Wisconsin. Flock structure was examined by measuring association among flock members in three ways: spatial proximity, temporal association, and association of individuals during flock movements. Additional information was obtained on aggressive interactions at and near the feeder. By midwinter, the strongest attachments were between males and females who subsequently mated; pair attachments strengthened as the breeding season approached. Lower ranked individuals in the dominance hierarchy showed weaker associations with other flock members in early spring than did more dominant individuals. The strong attachment to the mate may have implications for altruistic behavior within the winter flock. 相似文献
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This paper examines the key role that individual work reflection plays in facilitating individuals' leadership in teams. Consistent with the functional perspective on leadership, we argue that individual work reflection allows individuals to better understand their team's needs, and therefore enact higher levels of task-, relational-, and change-oriented leadership behaviors and be more effective leaders in their teams. We first conducted a series of measure development studies to validate a measure of individual work reflection comprising four dimensions of reflection at work: goals-, methods-, relationships-, and self-focused reflection. Then, across two independent studies assessing individuals in self-managing teams over time, we found support for our theoretical model linking individual work reflection to peer-rated leadership behaviors (Main Studies 1 and 2) and leadership effectiveness (Main Study 2). In further support of our theorizing, Main Study 2 also indicates that individual work reflection shapes leadership behaviors and effectiveness via understanding the team's needs, beyond a wide range of related constructs (e.g., feedback seeking, mindfulness, and rumination), as well as commonly studied predictors of leadership behaviors (i.e., the Big Five). Our theory and empirical findings help advance insights on the role of individual work reflection in improving leadership outcomes in organizations. 相似文献