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1.
Progressive succession of plant communities has been studied in cutover areas of bilberry-green moss forests of the alliance Dicrano-Pinion in the central upland part of the Southern Urals. The results are presented concerning the alpha-diversity and phytosociological spectrum of communities at different stages of succession.  相似文献   

2.
This study proposes the valuation of wetland functions as an alternative to the conventional approach to wetland valuation, in order to derive indicators for decision-making in wetland management. It is illustrated that these functions can be valuated in terms of the goods and services they provide to society. Using a functional approach, the functions are identified and the goods and services they provide are explicitly allocated among them; then, the latter are valuated with the Contingent Valuation method. Statistical analysis of the data provides welfare measures that reflect the value of these functions. It is argued that the values of separate functions are more useful in policy-making than their aggregated value.
Athanasios RagkosEmail: Phone: +30-2310-998826Fax: +30-2310-998828
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3.
The East Asian economy has been growing fast in recent years, and environmental stresses are building up rapidly. Transboundary air pollution, water shortages, drinking water contamination, freshwater and marine pollution, deforestation, climatic disasters, and other environmental problems are becoming serious threats to the well-being of people in this densely populated region. The ESI (environmental sustainability index) reported by the World Economic Forum in 2005 is a good indicator of the environmental status of the region; most East Asian countries ranked at the bottom. East Asia is not moving toward a sustainable society, and the environment will not sustain the current rate of economic development for long. The traditional culture of East Asia used to be sustainable, so we can learn much from our traditions. Land use should be planned from an ecological point of view so as to best preserve the land’s productivity and stability. There should be definite goals as to where and how much to preserve the three important ecological bases: forests, coastal wetlands and agricultural farms. The forest is the base for the terrestrial ecosystem, including flood control, water resources, and climate; the coastal wetland is the base for the marine ecosystem; farmland is the base for producing food. Within these defined goals, limits should be set on how much land can be utilized for activities like urban development, manufacturing, and recreation. Limits on the pollution load resulting from such activities should be set so as not to irreversibly damage the environment. Economic development should be planned to allow the use of energy and resources only after satisfying these constraints.
Jung Wk KimEmail: Phone: +82-2-8805653Fax: +82-2-8876905
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4.
Over 150 publications reporting studies conducted in the former USSR were reviewed to provide transfer coefficients (Ff) to the muscle of domestic animals from experiments using chronic administration, often for long timescales in large scale experiments. Only a few of these studies were made available in the English language literature or taken into account in international reviews. The values derived have been compared with expected values reported by the IAEA's Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) where possible. The information presented here has been used in the current updating of parameters recommended for environmental assessments by the IAEA. Many of the reported values are for Sr due to the Mayak accident and Cs due to the Chernobyl accident. Nevertheless, the reported data for a wide range of radionuclides, in particular for Ru, Sb, and Zn markedly improve the extent of available data.  相似文献   

5.
Basic climatic parameters (annual average air temperature and annual amount of precipitation) over 12–25 years have been analyzed with regard to their values corresponding to different levels of abundance in three species of forest voles: Clethrionomys glareolus (in 11 areas of the species range), Cl. rutilus, and Cl. rufocanus (in three areas each). The results show that the abundance of all these species correlates significantly with fluctuations of annual average temperature, with the correlation being negative in Cl. glareolus and Cl. rufocanus but positive in Cl. rutilus. In addition, the abundance of Cl. rufocanus shows a significant correlation with annual precipitation. Voles inhabiting different geographic regions may reach high abundance under different conditions. As for the species range as a whole, however, Cl. glareolus is more ecologically flexible than the other two voles. This species is also more warmth- and moisture-loving, while Cl. rufocanus is more cold-loving and xerophilous, with Cl. rutilus occupying an intermediate position between them. Clethrionomys rutilus is most temperature-dependent and stenothermic among them, whereas Cl. glareolus is indifferent to the factors studied.  相似文献   

6.
This report summarizes the results of two studies of electricity supply for Europe (EU), the Middle East (ME) and North Africa (NA) up to the year 2050. It shows that a transition to competitive, secure and sustainable supply of electricity and water is possible using renewable energy sources, efficiency gains and fossil fuel backup for balancing power. A strong cooperation between the EU and MENA for the market introduction of renewable energy and the interconnection of the electricity grids by high-voltage direct-current transmission are keys to the success and survival of the whole region. However, the necessary measures will take at least two decades to become effective. Therefore, adequate policy and economic frameworks for their realization must be introduced immediately. The importance of sustainable energy for the security of freshwater supplies in MENA is also described.
Hans Müller-SteinhagenEmail:
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7.
Data on radionuclide transfer to domestic chickens and ducks obtained from research performed in the former Soviet Union were reviewed to provide transfer coefficient values (Ff) to poultry and edible egg contents. The majority of the data are from experiments with 90Sr and 137Cs, reflecting the importance of these radionuclides after global fallout and major radiation accidents. Data for 3H, 54Mn, 59Fe, 60Co, 22Na 65Zn, 131I and U are also given. The values derived have been compared with those in the current IAEA Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) and the recent revision which incorporates the values from this paper. The Russian-language data give improved estimates for many radionuclides and the revised handbook is now based on the better quality data given for chronic administration.  相似文献   

8.
There is a mounting body of literature dealing generally with the dynamics of transitions of human systems towards sustainability and specifically with the different stages and processes of transitions. However, the question of why transition processes occur in the first place remains largely unexplained. This paper explores the concept of transition triggers, such as culture or material resource scarcity, and provides a theoretical framework to explain the emergence of a transition and its relation to recent developments in Spanish water policy. We adapt the general framework provided by current transition theory and gather empirical evidence and insights from processes occurring within the Spanish policy context and the Ebro river basin in particular. Our results show that the sole existence of biophysical limits to water use or development cannot explain the start of a possible sustainability transition in this domain in Spain. Changes in the existing water policies in the direction of sustainability were not ignited by people directly affected by water scarcities but by a coalition of sensitive agents, mostly from academia, NGOs and local constituencies, who managed to articulate new identities, integrate multiple sources of policy relevant knowledge, and develop new values under the umbrella of the new water culture movement.
Akgun IlhanEmail:
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9.
Terrascope is a freshman learning community at the Massachusetts Institute of Technology (MIT) in which teams of students work to find solutions to large ‘unsolvable’ problems and to communicate about those problems with a wide variety of audiences in multiple formats. The program strongly promotes students’ autonomy in focusing and structuring their work, and student projects culminate in public presentations, both to general audiences and to panels of technical specialists. Students who have completed the program tend to show strong engagement with environmental and sustainability issues, as well as the skills and experience to work intensively on such issues within multidisciplinary teams. Here, we present the program as a case study, with some discussion of the factors that are key to its operation.
Ari W. EpsteinEmail:
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10.
A new approach to quantifying and comparing vulnerability to drought   总被引:4,自引:1,他引:3  
In this study we develop an “inference modeling” approach to compare and analyze how different disciplines (economics, political science, and behavioral science/environmental psychology) estimate vulnerability to drought. It is thought that a better understanding of these differences can lead to a synthesis of insights from the different disciplines and eventually to more comprehensive assessments of vulnerability. The new methodology consists of (1) developing inference models whose variables and assertions incorporate qualitative knowledge about vulnerability, (2) converting qualitative model variables into quantitative indicators by using fuzzy set theory, (3) collecting data on the values of the indicators from case study regions, (4) inputting the regional data to the models and computing quantitative values for susceptibility. The methodology was applied to three case study regions (in India, Portugal and Russia) having a range of socio-economic and water stress conditions. In some cases the estimates of susceptibility were surprisingly similar, in others not, depending on the factors included in the disciplinary models and their relative weights. A new approach was also taken to testing vulnerability parameters by comparing estimated water stress against a data set of drought occurrences based on media analysis. The new methodologies developed in this paper provide a consistent basis for comparing differences between disciplinary perspectives, and for identifying the importance of the differences.
Joseph AlcamoEmail:
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11.
This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhão and Paraíba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites.  相似文献   

12.
13.
Policy sciences contributions to analysis to promote sustainability   总被引:1,自引:1,他引:0  
The policy sciences, in offering the most comprehensive approach to policy analysis and the sociopolitical processes that shape policy outcomes, is particularly appropriate for guiding the analysis required to promote sustainability. This article presents the main components of the policy sciences framework and demonstrates its potency in the crucial task of deepening the problem definitions required to select and enact policies to promote sustainability. As such, it provides background for the policy sciences articles of this special feature.
William AscherEmail:
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14.
Working toward sustainable community is a complex task for communities especially given the ambiguous nature of implementing the concept of sustainable development. However, by working to understand the nature of community capital, administrators can begin to move beyond bottom line thinking toward a more comprehensive and collective view of community. This paper presents a theoretical framework that helps municipal decision makers begin collecting information they need to help them build sustainable and resilient communities.
Edith G. CallaghanEmail:
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15.
This paper is a response to a recent special issue of Regional Environmental Change, “Quantifying vulnerability to drought from different disciplinary perspectives” (vol. 8, number 4, 2008). In this paper, we examine some of the challenges facing efforts to understand vulnerability to drought through quantification as they are manifest in some of the articles in this special issue.
Edward R. CarrEmail:
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16.
Predicting the transfer of radionuclides in the environment for normal release, accidental, disposal or remediation scenarios in order to assess exposure requires the availability of an important number of generic parameter values. One of the key parameters in environmental assessment is the solid liquid distribution coefficient, Kd, which is used to predict radionuclide–soil interaction and subsequent radionuclide transport in the soil column. This article presents a review of Kd values for uranium, radium, lead, polonium and thorium based on an extensive literature survey, including recent publications. The Kd estimates were presented per soil groups defined by their texture and organic matter content (Sand, Loam, Clay and Organic), although the texture class seemed not to significantly affect Kd. Where relevant, other Kd classification systems are proposed and correlations with soil parameters are highlighted. The Kd values obtained in this compilation are compared with earlier review data.  相似文献   

17.
Soil erosion in many parts of the developing world poses a threat to rural livelihoods, to the sustainbility of the agricultural sector, and to the environment. Most erosion prediction models are mechanistic and unsuited to quantify the severity of soil erosion in a data-limited developing world context. The model developed in this paper for Negros Island, in the central Philippines, is based on the Revised Universal Soil Loss Equation, but contains important innovations such as the movement of eroded soil over the landscape, simulating deposition on lower slopes and in waterways. It also includes a term describing farmer strategies to reduce soil erosion, which are typically ignored in erosion prediction models. A two-sample t-test found that model-predicted sediment loading values were not significantly different from field-measured sediment loading values when corrected for watershed size (P = 0.857). The model predicts an annual loss of 2.7 million cubic meters of sediment to waterways such that by 2050 more than 416,000 ha of agricultural land will be rendered unproductive due to erosion. Farmer behavior conserves soil, but on the steepest slopes soil conservation practices are not adequate to prevent erosion. Of two proposed strategies to control soil erosion in the rural Philippines, the model suggests that a complete switch to tree crops would conserve more soil than universal terrace adoption. However, even under these conservation scenarios, erosion threatens the areal extent of upland agriculture on Negros, and hence the sustainability of the island’s food supply.
Laura K. SchmittEmail:
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18.
Soil erosion is a major environmental problem and threat to rural development in Kenya. Numerous attempts to address the problem have apparently had little success. There are however some districts that have been very successful, notably Machakos. In this study we search for the factors that determine successful development in soil conservation such as social capital, human capital and market integration. One of our main results is that social capital measures are significant determinants of investment in soil conservation. A better understanding of the relevant mechanisms is essential for developing policies targeting improvement in natural resource management.
Wilfred NyangenaEmail:
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19.
The taxonomic diversity of the Hirudinea fauna and its dependence on the ecological conditions in the Bukhtarma Reservoir (Eastern Kazakhstan) have been studied. The morphological analysis has shown that these leeches belong to two orders and three families: Rhynchobdellida (families Glossiphoniidae and Piscicolidae) and Arhynchobdellida (family Erpobdellidae). On the whole, eight leech species from five genera (Alboglossiphonia, Helobdella, Theromyzon, Piscicola, and Erpobdella) have been identified. Among them, there are three glossiphoniid species (A. heteroclite, H. stagnalis, and T. tessulatum), two species of piscicolids (Piscicola geometra and Piscicola sp.), and three species of predatory leeches (E. octoculata, E. vilnensis, and Erpobdella sp.). Possible effects of hydrochemical parameters of the aquatic environment on the species diversity have been analyzed. Correlation has been revealed between the abundance of species and the physical and chemical characteristics of the environment.  相似文献   

20.
It is shown that the basidiocarps of many wood-decomposing fungi are inhabited by taxonomically and biomorphologically various eukaryotic (Charophyta, Chlorophyta, and Ochrophyta) and prokaryotic (Cyanophyta/Cyanobacteria) algae. They represent widespread eurybiont species and do not include any specialized mycetobionts. The communities formed by them have a host preference and green algae are their basic and obligate component, while other organisms are facultative components. Basidiocarps in which mycetobionts include heterocytic cyanoprokaryotes (Anabaena sp., Calothrix parietina, Hassallia byssoidea, Nostoc commune, N. punctiforme, Nostoc sp., and Scytonema ocellatum) are capable of molecular nitrogen fixation. Its activity is 0.044–0.903 mg of C2H4/m2/h in the basidiocarps of Bjerkandera adusta, Cerrena unicolor, Gloeophyllum sepiarium, and Trametes ochracea and 0.001–0.008 mg of C2H4/m2/h in the basidiocarps of Onnia leporina, Phellinus chrysoloma, Ph. tremulae, and Trametes pubescens. Basidiocarps without algae and those inhabited only by eukaryotic algae have no nitrogenase activity.  相似文献   

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