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851.
Sustainable development indicators (SDIs) have emerged as a tool to measure progress towards sustainable development for a number of fields. However, no indicator initiative to date has been aimed at biosolids management at local authority, regional or national levels. This paper presents a study where stakeholders involved in the management of biosolids in Ireland participated in the development of SDIs for managing biosolids at the local/regional level. A significant 81% of participating stakeholders find SDIs either 'useful' or 'very useful' as a tool for managing biosolids. A suite of 22 indicators has been developed and arranged according to the driving force-pressure-state-impact-response (DPSIR) indicator framework. The indicators address all the domains of biosolids management namely, production, quality, cost, legislation/regulation, training/research and recycling/disposal. The stakeholder approach is recognition that no effective indicator set can be developed without the input of stakeholders.  相似文献   
852.
The potential impacts of land use on large woody debris (LWD) were examined in Sourdough Creek Watershed, a rapidly growing area encompassing Bozeman, Montana, USA. We identified six land classes within a 250 m buffer extending on either side of Sourdough Creek and assessed aquatic habitat and geomorphologic variables within each class. All LWD pieces were counted, and we examined 14 other variables, including undercut bank, sinuosity, and substrate composition. LWD numbers were generally low and ranged from 0 to 8.2 pieces per 50 m of stream. Linear regression showed that LWD increased with distance from headwaters, riparian forest width, and sinuosity in four of the six land classes. Statistically significant differences between land classes for many aquatic habitat and geomorphologic variables indicated the impacts of different land uses on stream structure. We also found that practices such as active wood removal played a key role in LWD abundance. This finding suggests that managers should prioritize public education and outreach concerning the importance of in-stream wood, especially in mixed-use watersheds where wood is removed for either aesthetic reasons or to prevent stream flooding.  相似文献   
853.
Application of Conservation Biology Research to Management   总被引:1,自引:0,他引:1  
Abstract: We conducted a survey of all primary authors of "Contributed Papers" and "Research Notes" in Conservation Biology from 1987 to 1998 to assess the perceived effectiveness of published management recommendations. No systematic survey has previously assessed the degree to which authors believe that resource managers are using the growing body of research published in Conservation Biology . In March 1999, we sent surveys to 667 authors of 790 published papers, asking whether their papers included management recommendations, whether such recommendations have been used in practice, and why they believed they have or have not been used. We received completed surveys from 198 authors of 223 papers. The percentage of papers that included management recommendations increased from 1987 to 1991, then stabilized at about 75%. Author perception of the use of management recommendations generally increased over the 5 years from 1994 to 1998. Initiatives of federal, state, and local agencies were the most often-cited cause of successful implementation of management recommendations, accounting for over half of all such cases. Our survey suggests that authors in Conservation Biology have increased the use of explicit management recommendations in their papers and that authors believe their recommendations are being used to an increasing degree.  相似文献   
854.
The extent to which perfluorooctanesulfonate precursors (PreFOS) play a role in human or environmental exposure to perfluorooctanesulfonate (PFOS) is not well characterized. The diversity of manufactured PreFOS and its degradation products (e.g. C(8)F(17)SO(2)R and C(8)F(17)SO(2)NR'R', where R is H or F, and R' and R' are various) has made it difficult to track their fate. Temporal trends of PFOS in both humans and wildlife are discrepant, thus it is difficult to predict future exposure, and hypotheses about the role of PreFOS have been raised. Although abiotic degradation of commercially important PreFOS materials requires further research, current data suggest that the yield of PFOS is negligible or minor. On the other hand, in vivo biotransformation of PreFOS yields PFOS as the major metabolite, and >32% yields have been observed. In Canadians, exposure to PreFOS was equivalent or greater than direct PFOS exposure prior to 2002. In most ocean water, PFOS is dominant to PreFOS, but in the oceans east of Greenland there may be more PreFOS than PFOS, consistent with the fact that whales and humans in this region also show evidence of substantial PreFOS exposure. Quantitative assessments of PFOS body-burdens coming from PreFOS are complicated by the fact that PreFOS partitions to the cellular fraction of blood, thus biomonitoring in serum under predicts PreFOS relative to PFOS. Many unknowns exist that prevent accurate modelling, thus analytical methods that can distinguish directly manufactured PFOS, from PFOS that has been biotransformed from PreFOS, should be applied in future human and environmental monitoring. Two new source tracking principles are presented and applied to human serum.  相似文献   
855.
856.
857.
This study was conducted to determine the main sources of dissolved organic carbon (DOC) and disinfection byproduct (DBP) precursors to the McKenzie River, Oregon (USA). Water samples collected from the mainstem, tributaries, and reservoir outflows were analyzed for DOC concentration and DBP formation potentials (trihalomethanes [THMFPs] and haloacetic acids [HAAFPs]). In addition, optical properties (absorbance and fluorescence) of dissolved organic matter (DOM) were measured to provide insight into DOM composition and assess whether optical properties are useful proxies for DOC and DBP precursor concentrations. Optical properties indicative of composition suggest that DOM in the McKenzie River mainstem was primarily allochthonous--derived from soils and plant material in the upstream watershed. Downstream tributaries had higher DOC concentrations than mainstem sites (1.6 +/- 0.4 vs. 0.7 +/- 0.3 mg L(-1)) but comprised < 5% ofmainstem flows and had minimal effect on overall DBP precursor loads. Water exiting two large upstream reservoirs also had higher DOC concentrations than the mainstem site upstream of the reservoirs, but optical data did not support in situ algal production as a source of the added DOC during the study. Results suggest that the first major rain event in the fall contributes DOM with high DBP precursor content. Although there was interference in the absorbance spectra in downstream tributary samples, fluorescence data were strongly correlated to DOC concentration (R2 = 0.98), THMFP (R2 = 0.98), and HAAFP (R2 = 0.96). These results highlight the value of using optical measurements for identifying the concentration and sources of DBP precursors in watersheds, which will help drinking water utilities improve source water monitoring and management programs.  相似文献   
858.
Reconnecting to the Biosphere   总被引:3,自引:0,他引:3  
Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity.  相似文献   
859.
Much of the literature addressing environmental virtue tends to focus on what might be called “personal virtue”—individual actions, characteristics, or dispositions that benefit the individual actor. There has, in contrast, been relatively little interest in either “virtue politics”—collective actions, characteristics, or dispositions—or in what might be called “public virtues,” actions, characteristics, or dispositions that benefit the community rather than the individual. This focus, however, is problematic, especially in a society that valorizes individuality. This paper examines public virtue and its role in environmental virtue ethics. First, I outline different types of virtue in order to frame the discussion of public virtues and, in particular, a subclass of virtues I will refer to as political virtue. Second, I focus on practical problems and address the inadequacy of personal virtue for effecting social change and, therefore, for addressing most environmental crises. Finally, I argue that public and political virtues are necessary, if under emphasized, conditions for the flourishing of the individual, and that they are important complements to more traditional environmental virtues.  相似文献   
860.
Recent research has shown that many Australians see pro-environmental behaviour as desirable and identify as being green. However when compared to other countries, Australians score poorly on pro-environmental behaviour measures, engaging mostly in tokenistic pro-environmental actions, and demonstrate low levels of concern for the environment. In this article, we examine this tension through exploring the meaning of the term sustainability to Australian participants who self-identify as pro-environmental. Twenty-six interviews were conducted and analysed using a causal layered analysis. Through the examination of participants’ environmental discourse and practices, some of the deeper socio-psychological processes influencing pro-environmental behaviour are revealed. While participants aspired to be green, their actions were bound by cultural traditions and world views that perpetuate environmental degradation. Participants struggled to define the term sustainability and held self-enhancing motives for adopting what they identify as a pro-environmental identity. These findings highlight the influence of collective cultural constructs in shaping how pro-environmental behaviours are understood and enacted.  相似文献   
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