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21.
Design disciplines have a long history of creating well-integrated solutions to challenges which are complex, uncertain and contested by multiple stakeholders. Society faces similar challenges in implementing the Sustainable Development Goals, so design methods hold much potential. While principles of good design are well established, there has been limited integration of design thinking with sustainability science. To advance this integration, we examine the process of designing MetaMAP: an interactive graphic tool for collaborating to understand social–ecological systems and design well-integrated solutions. MetaMAP was created using Research through Design methods which integrate creative and scientific thinking. By applying design thinking, researchers and practitioners from different backgrounds undertook multiple cycles of problem framing, solution development, testing and reflection. The testing was highly collaborative involving over 150 people from diverse disciplines in workshops, case studies, interviews and critique. Reflecting on this process, we discuss design principles and opportunities for integrating design thinking with sustainability science to help achieve Sustainable Development Goals. 相似文献
22.
Maiti SK Das PK Ray SK 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(4):465-470
Chronic fluoride toxicity in the form of dental fluorosis was observed in cattle from nine (9) villages under two (2) blocks of Nayagarh district of Orissa. Out of 1117 cattle, 221 (18.09%) showed the signs of dental fluorosis. In all affected villages, the prevalence of dental fluorosis in calves (< 1 year age) was greater than adults. There was significant difference in prevalence in respect to age. The commonly observed signs of dental fluorosis were brown discoloration, mottling, attrition or uneven wearing of teeth with or without pitting. None of the affected animals showed characteristic signs of osteofluorosis. The mean serum and urine fluoride concentration of affected animals were significantly (P < 0.05) higher than those of control animals. Fluoride levels (mean) of ground water and surface water in two blocks were 1.30 +/- 0.16 ppm, 0. 66 +/- 0.08 ppm and 1.12 +/- 0.19 ppm, 0. 48 +/- 0.05 ppm respectively. The fluoride content of grass samples of affected and control (non-endemic) area was comparable. There was a highly positive correlation (r = + 0.664) between prevalence of dental fluorosis and fluoride content of ground water. It was concluded that fluoride intake through the water especially ground water contributed to the development of fluorosis in cattle. 相似文献
23.
Juvenile queen conch (Strombus gigas L.) occur in discrete aggregations within seemingly uniform seagrass beds throughout the Exuma Cays, Bahamas, suggesting that the aggregations occupy ecologically unique sectors of the habitat or that conch gain fitness by aggregated distribution. To examine the structure of a juvenile aggregation and to determine the underlying mechanisms which affect juvenile conch distribution, we axamined density, size composition, growth, survivorship, and movement patterns within a typical tidal-flow field nursery over a 14 mo period (August 1989 to September 1990). At the beginning of the study in August 1989, the conch population occupied 16.7 ha, with densities>0.2 juvenile conch m-2. The aggregation formed an ellipse, with longitudinal axis parallel to the main axis of the tidal current. Surveys conducted every 2 mo showed that conch density in the aggregation center remained constant while all other zones had lower densities which varied with time. In areas of high population density within the aggregation, several mass migrations of juveniles (20 to 99 conch m-2) occurred in early 1990. Tagged juveniles transplanted to zones outside the aggregation had high growth rates but suffered higher losses than individuals transplanted to the aggregation center. A tethering experiment confirmed the hypothesis that predator-induced mortality is significantly higher outside than inside the conch aggregation. Our results suggest that the queen conch aggregation occupied only a portion of the habitat that is optimal for feeding and growth. Aggregations could be maintained by differential mortality over a site; however, predation rates are probably density-dependent. Gregariousness, observed in translocation experiments, may provide an active mechanism for maintaining aggregated distribution and reducing mortality in conch nurseries. The ecological significance of aggregations should be considered in fisheries management and stock enhancement programs with queen conch. 相似文献
24.
Malcolm H. Ray 《Journal of Safety Research》1998,29(4):285-293
Clearzones are a feature of modern highways that have a dramatic impact on roadside safety. The purpose of these unobstructed spaces is to provide an area where an errant vehicle can safely stop or the driver can regain control of the vehicle without striking a hazardous object like a tree or utility pole. Many clearzone alternatives (e.g., removing trees, installing traversable culvert openings, and installing guardrails in front of untraversable hazards) are relatively inexpensive in comparison to other roadway construction costs. Roadways passing through rockcuts present an unusual case where the construction cost of providing the clearzone is very high. This article examines different clearzone alternatives in rockcuts and compares the likely effect on safety and construction costs. A method is described for determining the rockcut width that best balances the cost of construction with the improvements in safety that would result from a wider clearzone in the rockcut. 相似文献
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Effects of thickness on bacterial film 总被引:3,自引:0,他引:3
28.
A dual-permeability model (S_1D_DUAL) was developed to simulate the transport of land-applied pesticides in macroporous media. In this model, one flow domain was represented by the bulk matrix and the other by the preferential flow domain (PFD) where water and chemicals move at faster rates. The model assumed the validity of Darcian flow and the advective-dispersive solute transport in each of the two domains with inter-domain transfer of water and solutes due to pressure and concentration gradients. It was conceptualized that sorption and biodegradation rates vary with soil depth as well as in each of the two flow domains. In addition to equilibrium sorption, kinetic sorption was simulated in the PFD. Simulations were conducted to evaluate the combined effects of preferential flow, depth- and domain-variant sorption, and degradation on leaching of two pesticides: one with strong sorption potential (trifluralin) and the other with weak sorption potential (atrazine). Simulation results for a test case showed that water flux in the PFD was three times more than in the matrix for selected storm events. When equilibrium sorption was considered, the simulated profile of trifluralin in each domain was similar; however, the atrazine profile was deeper in the PFD than in the bulk matrix under episodic storm events. With an assumption of negligible sorption in the PFD, both the atrazine and the trifluralin profiles moved twice deeper into the PFD. The simulated concentrations of the chemicals were several orders higher in the PFD than in the matrix, even at deeper depths. The volume fraction of the macropores and the sorption and biodegradation properties of the chemicals could also affect the amount of pesticides leaving the root zone. For an intense storm event, slow sorption reaction rates in the PFD produced higher breakthrough concentrations of atrazine at the bottom of the simulated soil profile, thus posing the risk for breakthrough of chemicals from the root zone. 相似文献
29.
The protozoan, , metabolizes pentachloronitrobenzene to several products, including nitrite, pentachlorothioanisole and pentachloroaniline. The latter two metabolites were identified by gas chromatographymass spectrometry. Pentachlorothioanisole may be produced via a glutathione-dependent pathway, and two key enzymes of this pathway, glutathione transferase and thiol S-methyltransferase, have been detected in crude extracts of this microorganism. 相似文献
30.
Mamadou Fall Hasnaà Haddouk Stéphane Loriot Amadou Diouf Frédéric Dionnet Roy Forster 《毒物与环境化学》2013,95(10):1971-1981
The aim of this study was to investigate the potential mutagenic activity of diesel engine exhaust in the Ames/Salmonella assay using a direct aerosol exposure system. So, TA 98 and TA 100 strains, with or without added S9 mix, were exposed to diesel emissions after varying degrees of filtration. Variants of these two strains, deficient in nitroreductase (TA 98NR and TA 100NR) or over-expressing O-Acetyl Transferase (YG 1024 and YG 1029), were also exposed to total (unfiltered) diesel exhaust to highlight the putative mutagenicity of any nitro-PAHs present in these emissions. Mutagenic activity of the diesel exhaust was demonstrated on Salmonella typhimurium, strains TA 100 and variants TA 100 NR and YG1029. The use of a particle filter did not modify the genotoxicity of the diesel emissions, indicating a major contribution of the gas phase to the mutagenicity of these diesel emissions. The prominent role of the particulate-associated nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) claimed by some authors working on diesel exhaust organic extracts was not confirmed by our results with native diesel exhaust exposure. Our results show that the gas phase is potentially more mutagenic than the particles alone. 相似文献