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451.
Elke Herrfahrdt-Pähle 《Regional Environmental Change》2013,13(3):551-561
Climate change and its impact on water resources have become a reality in many parts of the world. Uncertainties in water supply as well as the gradual and abrupt change in water availability are increasing. To maintain the sustainability of the water sector, its ability to adapt to unforeseen events needs to increase. Making adaptation an integral part of the governance of water resources will thus be one of the major future challenges for the water sector. This paper focuses on how far Integrated Water Resource Management (IWRM), the guiding concept of water management and governance, is able to address these challenges and which additional features would be required for increasing the adaptability of water governance and management. In the empirical part of the paper, South African water legislation and its adaptability to the challenges of climate change is scrutinised. The paper finds that IWRM offers a number of entry points for increased adaptability. However, the IWRM concept should be complemented with features of adaptive governance such as polycentric, redundant and flexible governance structures to be better prepared for unforeseen events. It is concluded that the features of IWRM and adaptive water governance comprise a number of synergies and trade-offs, which play out differently in different combinations and contexts. The paper outlines the need for further empirical research on these trade-offs as well as on the appropriate degree of features such as participation, flexible institutions and redundancy. 相似文献
452.
Järvi Järveoja Janika Laht Martin Maddison Kaido Soosaar Ivika Ostonen Ülo Mander 《Regional Environmental Change》2013,13(4):781-795
Abandoned peat extraction areas are continuous emitters of GHGs; hence, abandonment of peat extraction areas should immediately be followed by conversion to an appropriate after-use. Our primary aim was to clarify the atmospheric impact of reed canary grass (RCG, Phalaris arundinacea L.) cultivation on an abandoned peat extraction area and to compare it to other after-treatment alternatives. We performed a life-cycle assessment for five different after-use options for a drained organic soil withdrawn from peat extraction: (I) bare peat soil (no management), (II) non-fertilised Phalaris cultivation, (III) fertilised Phalaris cultivation, (IV) afforestation, and (V) rewetting. Our results showed that on average the non-fertilised and fertilised Phalaris alternatives had a cooling effect on the atmosphere (?10,837 and ?477 kg CO2-eq ha?1 year?1, respectively), whereas afforestation, rewetting, and no-management alternatives contributed to global warming (9,511, 8,195, and 2,529 kg CO2-eq ha?1 year?1, respectively). The main components influencing the global warming potential of different after-use alternatives were site GHG emissions, carbon assimilation by plants, and emissions from combustion, while management-related emissions played a relatively minor role. The results of this study indicate that, from the perspective of atmospheric impact, the most suitable after-use option for an abandoned peat extraction area is cultivation of RCG. 相似文献
453.
Lensu T Komonen A Hiltula O Päivinen J Saari V Kotiaho JS 《Journal of environmental management》2011,92(10):2539-2546
Habitat loss is one of the greatest threats for biodiversity. In Finland, two thirds of natural mires have been drained for silviculture, which transforms open wetlands into dense forests. However, vegetation management of power line rights-of-way (ROW) maintain the drained mires as open areas. The aim of this study was to determine the effect of the power line ROW vegetation management on butterfly abundance, species richness and community structure by comparing the managed power line ROWs to unmanaged drained control sites and to natural mires. The species richness or abundance of mire butterflies did not differ between the power line ROWs and natural mires. In contrast, both species richness and abundance of butterflies was low on the unmanaged control sites. Tree canopy cover had a negative effect on mire butterflies and this is most likely related to changes in microclimate. The results indicate that the active vegetation removal in the power line ROWs maintain alternative habitats for mire butterflies; yet, the power line ROWs cannot substitute the natural mires. 相似文献
454.
Ben Vanpeperstraete Sébastien Duyck Medani P. Bhandari Janis Brizga Leida Rijnhout Sylvia Lorek A. Peter Castro Chiung Ting Chang Herman Daly Robert J. Didham Gianluca Ferraro Oliver Greenfield Ashok Khosla Ernst Ulrich von Weizsäcker Birgit Lode Simon Miles Henrique Pacini Semida Silveira Leisa Perch Jaap Rijnsburger Mukul Sanwal Sameera Savarala S. Jacob Scherr Kallidaikurichi E. Seetharam A.M.M. Adeeb Donna Shepherd Adrian Smith Lisinka Ulatowska Alice Vincent Werner John 《Natural resources forum》2011,35(4):334-342
455.
Vilis Brukas Andrius Kuliešis Ola Sallnäs Edgaras Linkevičius 《Natural resources forum》2011,35(2):77-88
As tensions among diverse forest‐use interests in Lithuania are on the rise, this study examines the actual resource availability, the underlying planning approaches and the pertinent policy arena. Two 5‐year cycles of sampling‐based forest inventory provide accurate data showing that the overall timber harvest/increment ratio (or utilization intensity) is 61%. Utilization intensity is similar in state and private forests. It could potentially be raised to 70‐80%, with due account for environmental values. Such an increase is inhibited by rigid routines of forest management planning, involving inflexible rotation ages and cutting norms. Age‐class analysis indicates that the current planning practice counters its underlying aim of achieving a long‐term even flow of timber. According to a survey of key forest stakeholders, those who directly benefit from forest utilization have a weak position in the policy arena, the dominant powers being vested in the national forestry authorities. State forest enterprises have to follow restrictive plans from above, private forest owners are constrained by stern regulations and suffer from the bad image caused by the persistent myth of overuse in private forests. More rational management of Lithuanian forests is hardly possible without major shifts in the institutional set‐up accompanied by transformation of the professional ideology. 相似文献
456.
Maintaining the Conservation Value of Shifting Cultivation Landscapes Requires Spatially Explicit Interventions 总被引:1,自引:0,他引:1
Fallow vegetation within landscapes dominated by shifting cultivation represents a woody species pool of critical importance
with considerable potential for biodiversity conservation. Here, through the analysis of factors that influence the early
stages of fallow vegetation regrowth in two contrasting forest margin landscapes in Southern Cameroon, we assessed the impact
of current trends of land use intensification and expansion of the cultivated areas, upon the conservation potential of shifting
cultivation landscapes. We combined the analysis of plot and landscape scale factors and identified a complex set of variables
that influence fallow regrowth processes in particular the characteristics of the agricultural matrix and the distance from
forest. Overall we observed a decline in the fallow species pool, with composition becoming increasingly dominated by species
adapted to recurrent disturbance. It is clear that without intervention and if present intensification trends continue, the
potential of fallow vegetation to contribute to biodiversity conservation declines because of a reduced capacity, (1) to recover
forest vegetation with anything like its original species composition, (2) to connect less disturbed forest patches for forest
dependent organisms. Strategies to combat biodiversity loss, including promotion of agroforestry practices and the increase
of old secondary forest cover, will need not only to operate at a landscape scale but also to be spatially explicit, reflecting
the spatial pattern of species reservoirs and dispersal strategies and human usage across landscapes. 相似文献
457.
In most birds, natal dispersal is female-biased, but the selective pressures leading to this pattern have rarely been explored
with comprehensive data on lifetime reproductive success. In territorial birds, the benefit of philopatry should be higher
for males than for females when males establish territories for which knowledge about the local environment is important.
As females may use male characteristics for mate choice, and hence indirectly for territory choice, the benefit from the direct
knowledge of the local environment may be lower for females than males. We tested this hypothesis using data from a long-term
study of group living corvids, the Siberian jays (Perisoreus infaustus). In this species, the socially dominant offspring delay dispersal while the sub-dominant offspring leave the family group
directly after reaching independence. Our results show that natal dispersal distance (a proxy for local knowledge) was related
to sex and dispersal timing (a proxy for “quality”): Females and early dispersers traveled further on average than males and
delayed dispersers. Furthermore, dispersal distance and timing were negatively related to the number of recruits produced
over an individual’s lifetime in males, but not in females. Hence, the results support the hypothesis that the female-biased
natal dispersal found in this and other bird species may come about through higher lifetime reproductive success of philopatric
males than females. 相似文献
458.
Angelika Hilbeck Matthias Meier Jörg Römbke Stephan Jänsch Hanka Teichmann Beatrix Tappeser 《Environmental Sciences Europe》2011,23(1):1-12
Purpose
The purpose of the study is the enhancement of criticality assessments for resources in order to address function specific factors like dissipation, recycling, bio-activity and toxicity. The developed methodology is applied to platinum-containing cytostatic drugs and automotive catalytic converters.Methods
The study is methodically based on an analysis of resource specific factors like exploration rates, reserves-to-production ratio and regional distribution of exploration areas as well as on the investigation of product/functional depending factors like recycling rates, dissipation rates, bio-diversity and toxicity. Taking into account that economic and ecological risks may occur at any stage of the supply, consumption and dissipation processes, the whole life cycles of the two analyzed products (cytostatic drugs and automotive catalytic converters) are considered. As an approach to reduce potential economic and ecological risks the study is especially focused on recycling strategies.Background
In order to get a better understanding of platinum as an essential resource for the development of our society the history and the cultural impact of the term "resource" are introduced.Results & Discussion
The availability of platinum is crucial for several products of our modern society. Areas of application are e.g. jewellery, automotive catalytic converters, investments (coins, bars), computers, mobile devices, fertilizers and cytostatic drugs. Economic risks are caused by limited sources and dynamic demand of new application areas like fuel cells and drugs. Platinum-containing drugs are used for the treatment of several kinds of cancer such as testicular, breast, colon and prostate. Currently the pharmaceutical industry requires 6,9 tons per year (3 percent of the total demand of platinum). Due to the improvement of medical standards and the ageing society, especially in developing countries, the demand of platinum-containing drugs will rise significantly. The dissipation of toxic soluble salts and the lack of advanced waste-water treatment and recycling systems is a problem of the usage of platinum-containing drugs. Compared with cytostatic drugs (14.6 kg/a for Germany) the dissipation of platinum particles of mobile catalytic converters is much higher (5-20 tons/a only in North America, Europe and Japan; 184,2 kg/a in Germany). On the other hand the emission of platinum nano-particles of automotive catalytic converters seems less critical. Furthermore advanced recycling technologies are already available for them.Conclusions
The evaluation of resources has to consider resource specific and functional depending factors. In order to reduce economic and ecological risks of the dissipation of platinum salts in cytostatic drugs three principle options can be identified: the development of ecologically compatible and cost-effective substitutes, efficient recycling systems and future-oriented sanitary-systems as well as waste-water treatment facilities, which are able to separate platinum salts. Concerning the dissipation of platinum particles of mobile converters relevant research questions are the identification of adequate substitutes as well as the extension of recycling capacities.Recommendations and perspectives
The study demonstrates a research gap concerning substitutes for automotive catalytic converters as well as for platinum-containing cytostatic drugs. The development and implementation of recycling concepts, technologies and capacities to reuse platinum as a secondary resource is an essential issue. As a consequence the economic and ecological risks can be reduced by increasing the resource efficiency. Special research has to be done concerning the development of future-oriented sanitary-systems and waste-water treatment facilities in order to separate platinum in waste water. Furthermore, if the future demand of new products like fuel cells is considered, a resource conflict concerning the potential functional applications will be evident. In order to address these challenges the criticality assessment has to be enhanced by ethic and social factors. 相似文献459.
460.
Today's large-scale poultry production is often accompanied by high concentrations of airborne microorganisms at working places. However, the microbial communities in those bioaerosols are rarely characterised. In this study, we investigated the bacterial population in bioaerosols from a duck hatchery by both cultivation based and molecular methods and compared the results. Depending on used media, concentrations of airborne culturable bacteria varied between 6 × 10(1) and 7 × 10(6) CFU per m(3) air. The corresponding total cell count of DAPI stained cells was 2 × 10(7) cells per m(3) air. 16S rRNA gene analyses of bacterial isolates and clone libraries revealed a low species richness in hatcheries air, respectively. More than 50% of bacterial isolates were phylogenetically most closely related to bacterial species of the risk group 2 (German TRBA). The sequence composition in clone libraries supported the result of cultivation based approaches, whereby sequences assigned to Staphylococcus, Acinetobacter and Enterococcus are the most common. The high concentration of airborne bacteria which are most closely related to species of potential health risk requires further detailed investigations for these bacterial species. 相似文献