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61.
Although planning scholars often argue that public participation improves implementation outcomes, this relationship is rarely empirically tested. This study investigates how public engagement, during planning and after plan adoption, impacts on the speed of local government sustainability plan implementation. It includes a correlation analysis of quantized in-depth interviews with sustainability planners in 36 American cities. The study finds that individual characteristics of public engagement, both during planning and after plan adoption, had statistically significant relationships to implementation speed, but in some cases this relationship was negative. The correlations imply that sustainability planners can make strategic choices to improve implementation speed through public participation in plan creation and after plan adoption. Alternatively, planners also make choices during participatory planning that slow implementation, a problematic outcome when the ultimate goal of a planning process is on-the-ground change.  相似文献   
62.
For marine organisms, decoupling between the planktonic larval stage and the benthic-associated juvenile stage can lead to variable patterns of population replenishment, which have the potential to influence the effectiveness of marine reserves. We measured spatial and temporal variability in larval supply and recruitment of fishes to coral reefs of different protection levels and tested whether protection level influenced the relationship between supply and recruitment. We sampled pre-settlement larvae and newly settled recruits from four reefs (two reserves and two non-reserves) in the Florida Keys National Marine Sanctuary, USA. Replicate point measures of larval supply over 14 months and 17 monthly measurements of recruitment varied significantly among months and sites. Sites with the same protection level had significantly different patterns of larval supply as well as larval and recruit diversity, but recruitment magnitude differed only by protection level, where densities were greater at reserves. Differences in larval supply among sites included two particularly large peaks in larval abundance at one site, possibly associated with the observed passage of small-scale oceanographic features. To examine whether relationships between larval supply and recruitment varied by protection level, we selected one species that was present in both the light trap samples and the monthly recruitment surveys. Recruitment of the bicolor damselfish Stegastes partitus was significantly and positively related to larval supply at three of the four sites thus, protection level did not influence this linkage. Since local variability among sites can lead to spatial differences in population replenishment, characterization of larval supply and recruitment to potential marine reserve sites may help to identify optimal locations in a region and contribute to more effective reserve design.  相似文献   
63.
The occurrence and rates of terminal electron acceptor processes, and recharge processes in the unsaturated zone of a boreal site contaminated with petroleum hydrocarbons in the range C(10) to C(40) were examined. Soil microcosms were used to determine the rates of denitrification, iron (Fe) reduction, sulfate (SO(4)) reduction, and methanogenesis in two vertical soil profiles contaminated with oil, and in a noncontaminated reference sample. Furthermore, the abundances of the 16S rRNA genes belonging to Geobacteracaea in the samples were determined by real-time quantitative polymerase chain reaction (PCR). Analyses of ground water chemistry and soil gas composition were also performed together with continuous in situ monitoring of soil water and ground water chemistry. Several lines of evidence were obtained to demonstrate that both Fe reduction and methanogenesis played significant roles in the vertical profiles: Fe reduction rates up to 3.7 nmol h(-1) g(-1) were recorded and they correlated with the abundances of the Geobacteracaea 16S rRNA genes (range: 2.3 x 10(5) to 4.9 x 10(7) copies g(-1)). In the ground water, ferrous iron (Fe(2+)) concentration up to 55 mg L(-1) was measured. Methane production rates up to 2.5 nmol h(-1) g(-1) were obtained together with methane content up to 15% (vol/vol) in the soil gas. The continuous monitoring of soil water and ground water chemistry, microcosm experiments, and soil gas monitoring together demonstrated that the high microbial activity in the unsaturated zone resulted in rapid removal of oxygen from the infiltrating recharge thus leaving the anaerobic microbial processes dominant below 1.5 m depth both in the unsaturated and the saturated zones of the subsurface.  相似文献   
64.
This paper presents a Life Cycle Assessment of a hemp fibre reinforced component for automotive parts. Its aim is to identify the optimisation strategies within the product system and also provide decision support for automotive engineers for or against the employment of renewable raw materials within the production process. The investigated life cycle contains the agricultural cultivation of the fibre plant, the method of harvesting and the processing of the crop. The analysis includes the further processing of the fibre, i.e. the manufacturing of the fibre composite matrix, on which the production of form press components for the automotive industry is based. Manufacturing the required preproducts is also taken into account. The differences of energy demand (CED) and emission amount during the use phase of a passenger car and different disposal options for the end of the life cycle (deposition or incineration) are assessed as well. It is shown that the natural fibre composite is ecologically preferable to the injection moulded reference as the results of the Eco-indicator 95 method show. Optimisation is necessary for the epoxy-resin-hardener system, although the cultivation of fibre plants is ecologically an insignificant process regarding the system boundaries. The weight difference and resulting energy savings during the use phase of a car reveal further advantages of a fibre panel.  相似文献   
65.

The presented research concerned the compatibility of cosolvents with in situ alkaline hydrolysis (ISAH) for treatment of organophosphorous (OPP) pesticide contaminated sites. In addition, the influence of moderate temperature heat increments was studied as a possible enhancement method. A complex dense non-aqueous phase liquid (DNAPL) of primarily parathion (~50 %) and methyl parathion (~15 %) obtained from the Danish Groyne 42 site was used as a contaminant source, and ethanol and propan-2-ol (0, 25, and 50 v/v%) was used as cosolvents in tap water and 0.34 M NaOH. Both cosolvents showed OPP solubility enhancement at 50 v/v% cosolvent content, with slightly higher OPP concentrations reached with propan-2-ol. Data on hydrolysis products did not show a clear trend with respect to alkaline hydrolysis reactivity in the presence of cosolvents. Results indicated that the hydrolysis rate of methyl-parathion (MP3) decreased with addition of cosolvent, whereas the hydrolysis rate of ethyl-parathion (EP3) remained constant, and overall indications were that the hydrolysis reactions were limited by the rate of hydrolysis rather than NAPL dissolution. In addition to cosolvents, the influence of low-temperature heating on ISAH was studied. Increasing reaction temperature from 10 to 30 °C provided an average rate of hydrolysis enhancement by a factor of 1.4–4.8 dependent on the base of calculation. When combining 50 v/v% cosolvent addition and heating to 30 °C, EP3 solubility was significantly enhanced and results for O,O-diethyl-thiophosphoric acid (EP2 acid) showed a significant enhancement of hydrolysis as well. However, this could not be supported by para-nitrophenol (PNP) data indicating the instability of this product in the presence of cosolvent.

  相似文献   
66.
This article highlights the relationship between walruses and humans in and around the North Water polynya in a long-term perspective. The present study draws on a combination of biological, archaeological, archaeo-zoological, historical, and ethnographic sources covering the period from the 8th century ad to the late 20th century. The study demonstrates that the walrus was an important resource of meat, blubber, and other products throughout all the studied periods, if always supplemented by other kinds of game. It is suggested that walrus distribution and behaviour, as well as hunting strategies and technologies historically constituted a powerful component not only in forming human action and social life in the region but also in serving as an imaginative resource. It is further argued that the walrus and the walrus hunt still play a significant role in the present community living on the edge of the North Water, even if the hunt is increasingly circumscribed due to changing ice conditions.  相似文献   
67.
Resilience thinking has developed separately in the bodies of literature on social-ecological systems, and that published principally within developmental psychology and mental health on the resilience of individuals. This paper explores what these bodies of literature might learn from the other towards a more integrated and enriched understanding of both social-ecological systems and social resilience. The psychology-based literature recognises a strong set of factors that enhance the strengths of individuals and communities, but lacks a sophisticated integration of the physical environmental context. The social-ecological systems literature offers an excellent foundation in complex adaptive systems, but tends to superimpose ecological concepts of system function onto the human domain, and needs to include an array of core social science concepts that are important to a full understanding of social-ecological systems. An example on north eastern Australia suggests how a converged understanding of social resilience could assist managers to acknowledge, enhance and foster social resilience in linked social-ecological systems.  相似文献   
68.
69.
Book review     
Drawing on the example of community forestry in British Columbia, Canada, this paper conceptualises and empirically assesses key contributors to successful community economic development, with a special emphasis on the role of local community support and inclusive participation. Relevant scholarship highlights the importance of these factors for achieving success with any community economic development (CED) initiative. While the initial experiences of 10 community forest initiatives under British Columbia's Community Forest Pilot Project offers evidence to corroborate this view, it is also evident that expertise and leadership, even of the exclusive variety, can substitute for community support and participation, if the goal of CED is to create a profitable community enterprise capable of delivering jobs and revenues to community members.  相似文献   
70.
Residues of three phenazone-type pharmaceuticals have been identified in routine analyses of groundwater samples from selected areas in the north-western districts of Berlin, Germany. Phenazone, propiphenazone, and dimethylaminophenazone have been detected in some wells at concentrations up to the low microg/l-level. Additionally, three phenazone-type metabolites namely 1-acetyl-1-methyl-2-dimethyl-oxamoyl-2-phenylhydrazide (AMDOPH), 1-acetyl-1-methyl-2-phenylhydrazide, and dimethyloxalamide acid-(N'-methyl-N-phenyl)-hydrazide have also been identified in these groundwater samples. The residues are suspected to originate from former production spills of a pharmaceutical plant located in a city north of Berlin. It was observed that with the exception of AMDOPH all other residues were efficiently removed during conventional drinking water treatment. The drug metabolite AMDOPH deriving from dimethylaminophenazone residues was found at concentrations of 0.9 microg/l in finished drinking water. However, a following study on the toxicological relevance of the AMDOPH residues has shown that there is no toxicological harm for humans at the low concentrations of AMDOPH observed in Berlin drinking water.  相似文献   
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