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31.
The number of collaborative initiatives between scientists and volunteers (i.e., citizen science) is increasing across many research fields. The promise of societal transformation together with scientific breakthroughs contributes to the current popularity of citizen science (CS) in the policy domain. We examined the transformative capacity of citizen science in particular learning through environmental CS as conservation tool. We reviewed the CS and social‐learning literature and examined 14 conservation projects across Europe that involved collaborative CS. We also developed a template that can be used to explore learning arrangements (i.e., learning events and materials) in CS projects and to explain how the desired outcomes can be achieved through CS learning. We found that recent studies aiming to define CS for analytical purposes often fail to improve the conceptual clarity of CS; CS programs may have transformative potential, especially for the development of individual skills, but such transformation is not necessarily occurring at the organizational and institutional levels; empirical evidence on simple learning outcomes, but the assertion of transformative effects of CS learning is often based on assumptions rather than empirical observation; and it is unanimous that learning in CS is considered important, but in practice it often goes unreported or unevaluated. In conclusion, we point to the need for reliable and transparent measurement of transformative effects for democratization of knowledge production.  相似文献   
32.
The nitrifying activity and the effect of fertilization with urea and methylene urea were studied in a landfarming site. The site has been operative over 20 years and maintained by heavy nitrogen fertilization. The landfarming soil contained 4-6% (w/w) oil. The nitrate accumulation was 20-50mg NO3-N day(-1)kg(-1) observed after methylene urea fertilization of 889 g Nm(-2). Nitrification ex situ (in laboratory conditions) was 8.8 mg NO3-N day(-1) kg(-1) in the presence of 380 mg kg(-1) NH4+-N. The half-saturation concentration of nitrification was more than 200 mg NH4+-N kg(-1). The results show that nitrification was active in soil with high oil concentration. Urea fertilization of 893 g Nm(-2) caused an increase of soil NH4+-N concentration up to 5500 mg kg(-1) and pH>8.5. This led to inhibition of nitrification, which persisted after NH4+ concentration decreased below 200mg NH4+ kg(-1).  相似文献   
33.
Degradation of potassium formate in the unsaturated zone of a sandy aquifer   总被引:1,自引:0,他引:1  
This paper presents results from a lysimeter experiment on the fate of potassium formate, an alternative deicing agent. The experiment was performed through the winter and spring to identify any thermal sensitivity in the transport and biodegradation of formate in the lysimeter. Ninety-eight percent of the total quantity of formate applied was degraded while percolating through the 1.7-m-thick unsaturated sand layer within the lysimeter. Concomitantly, the bicarbonate concentration of the percolating water increased. The low concentrations of nitrogen (0.02 mg L(-1)) and phosphorous (<0.002 mg L(-1)) in the percolated water, however, potentially limited microbial activity. During the study period, 99% of the applied potassium was retained in the lysimeter, and the ion exchange between the potassium and a variety of monovalent and divalent ions was assumed to be responsible for the leaching of barium, calcium, magnesium, and sodium from the soil material. Except for manganese, the concentrations of the studied metals in the percolated water did not exceed the threshold values set for drinking water by the Council of the European Union. By contrast, the application of potassium formate had a detrimental effect on the vegetation on the lysimeter. To conclude, formate was effectively degraded in the sandy lysimeter and its application did not cause major undesirable changes in the quality of the percolating water. Further research at field scale is, however, needed for instance on the biodegradation of potassium formate and on its impacts on roadside vegetation.  相似文献   
34.
In this study, long-term aerosol particle total number concentration measurements in five metropolitan areas across Europe are presented. The measurements have been carried out in Augsburg, Barcelona, Helsinki, Rome, and Stockholm using the same instrument, a condensation particle counter (TSI model 3022). The results show that in all of the studied cities, the winter concentrations are higher than the summer concentrations. In Helsinki and in Stockholm, winter concentrations are higher by a factor of two and in Augsburg almost by a factor of three compared with summer months. The winter maximum of the monthly average concentrations in these cities is between 10,000 cm(-3) and 20,000 cm(-3), whereas the summer min is approximately 5000-6000 cm(-3). In Rome and in Barcelona, the winters are more polluted compared with summers by as much as a factor of 4-10. The winter maximum in both Rome and Barcelona is close to 100,000 cm(-3), whereas the summer minimum is > 10,000 cm(-3). During the weekdays the maximum of the hourly average concentrations in all of the cities is detected during the morning hours between 7 and 10 a.m. The evening maxima were present in Barcelona, Rome, and Augsburg, but these were not as pronounced as the morning ones. The daily maxima in Helsinki and Stockholm are close or even lower than the daily minima in the more polluted cities. The concentrations between these two groups of cities are different with a factor of about five during the whole day. The study pointed out the influence of the selection of the measurement site and the configuration of the sampling line on the observed concentrations.  相似文献   
35.
Residential heating is an important local source of fine particles and may cause significant exposure and health effects in populations. We investigated the cytotoxic and inflammatory activity of particulate emissions from normal (NC) and smouldering (SC) combustion in one masonry heater. The PM1–0.2 and PM0.2 samples were collected from the dilution tunnel with a high-volume cascade impactor (HVCI). Mouse RAW 264.7 macrophages were exposed to the PM-samples for 24 h. Inflammatory mediators, (IL-6, TNFα and MIP-2), and cytotoxicity (MTT-test), were measured. Furthermore, apoptosis and cell cycle of macrophages were analyzed. The HVCI particulate samples were characterized for ions, elements and PAH compounds. Assays of elemental and organic carbon were conducted from parallel low volume samples. All the samples displayed mostly dose-dependent inflammatory and cytotoxic activity. SC samples were more potent than NC samples at inducing cytotoxicity and MIP-2 production, while the order of potency was reversed in TNFα production. SC-PM1–0.2 sample was a significantly more potent inducer of apoptosis than the respective NC sample. After adjustment for the relative toxicity with emission factor (mg MJ?1), the SC-PM emissions had clearly higher inflammatory and cytotoxic potential than the NC-PM emissions. Thus, operational practice in batch burning of wood and the resultant combustion condition clearly affect the toxic potential of particulate emissions.  相似文献   
36.
Outotec open cycle (OOC) is a new low-energy process linking together production of hydrogen and sulfuric acid. While sulfuric acid is the world’s most widely produced chemical by mass at approximately 200 Mt/a, the OOC gives the potential for making 4 Mt/a of hydrogen gas as a by-product. H2SO4 manufacture requires a source of sulfur dioxide. 30% of world production of H2SO4 is from the SO2 by-product of pyrometallurgical processing of sulfur containing concentrates of metals such as copper, nickel and zinc. SO2 can also be made by direct combustion of sulfur. In OOC, a divided electrochemical cell is used for SO2-depolarized electrolysis of water. SO2 is fed to the anolyte and converted to H2SO4, while hydrogen gas is produced at the cathode. On the industrial scale, the equipment will be in the form of a membrane electrolyzer assembly or stack. A case is described where the OOC would be connected to a pyrometallurgical plant smelting 1 Mt/a of nickel and copper concentrate, producing 1 Mt/a of H2SO4 and 20 kt/a of hydrogen.  相似文献   
37.
Drawing on the wide social scientific literature on emotions and affects, we highlight the value and potential contribution of the affect theory for understanding public engagement in environmental policy and planning. We suggest that such theorization complements political ontologies that envision concerned publics to arise as citizens are attached to objects and other beings in their everyday life. Focus on emotions and affects enables in-depth exploration of the corporeality of these attachments, increasing understanding about how affected publics get driven for action and how new sensibilities and horizons for action are created. Based on the discussion of affect theory and case examples, we argue that emotions and affects should be treated as crucial carriers of knowledge about transformation of political subjects and their concerns. They also direct analytic gaze beyond public participation procedures and encourage the development of novel, more inclusive settings for public engagement.  相似文献   
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