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101.
ABSTRACT

The sustainable city of the future is typically envisioned as smart, creative and disruptive, assuming that urban and local sustainability is achieved through new technology and innovation. However, considering that the built environments of our cities and surroundings are highly durable, there is also a need to focus on how resources brought from the past – histories, artefacts and places – may be used for promoting urban sustainability. We label this a “deep city” perspective on urban and local transformation. By looking at Røros, a World Heritage Site in central Norway with a dense and historic wooden urban centre, we investigate how its heritage protection facilitates the maintenance of a compact urban centre. We hold that a shared sense of place – the deepness– may serve as a resource against unsustainable sprawl and mall-oriented development.  相似文献   
102.
Climatic records from equatorial eastern Africa and subtropical southern Africa have shown that both temperature and the amount of rainfall have varied over the past millennium. Moreover, the rainfall pattern in these regions varied inversely over long periods of time. Droughts started abruptly, were of multi-decadal to multi-centennial length and the changes in the hydrological budget were of large amplitude. Changing water resources in semi-arid regions clearly must have regional influences on both ecological and socio-economic processes. Through a detailed analysis of the historical and paleoclimatic evidence from southern and eastern Africa covering the past millennium it is shown that, depending on the vulnerability of a society, climatic variability can have an immense impact on societies, sometimes positive and sometimes disastrous. Therefore, the interconnected issue of world ecosystem and social resilience is the challenge for decision-makers if sustainable development is to be reached on global and local levels.  相似文献   
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105.
Promoting sustainable forest management as part of the reduced emissions from deforestation and degradation in developing countries (REDD)-plus mechanism in the Copenhagen Accord of December 2009 implies that tropical forests will no longer be ignored in the new climate change agreement. As new financial incentives are pledged, costs and revenues on a 1-ha tract of tropical forestland being managed or cleared for other land use options need to be assessed so that appropriate compensation measures can be proposed. Cambodia's highly stocked evergreen forest, which has experienced rapid degradation and deforestation, will be the first priority forest to be managed if financial incentives through a carbon payment scheme are available. By analyzing forest inventory data, we assessed the revenues and costs for managing a hypothetical 1 ha of forestland against six land use options: business-as-usual timber harvesting (BAU-timber), forest management under the REDD-plus mechanism, forest-to-teak plantation, forest-to-acacia plantation, forest-to-rubber plantation, and forest-to-oil palm plantation. We determined annual equivalent values for each option, and the BAU-timber and REDD-plus management options were the highest, with both options influenced by logging costs and timber price. Financial incentives should be provided at a level that would allow continuation of sustainable logging and be attractive to REDD-plus project developers.  相似文献   
106.
Each year an estimated 328,500 infants age 0-12 months are treated for unintentional injuries in emergency departments (EDs): one infant every minute and a half. The leading cause, overall and by month of age, was fall-related injury. The second leading cause was 'struck by or against.' The majority of patients were injured at home. Younger infants were more likely to be hospitalized than older ones and more males than females were injured. Gender differences suggest that parenting practices may play a role, but ecological approaches should be considered in an effort to understand the connection between injuries and an infant's developmental stage.  相似文献   
107.
Virgin female cabbage butterflies, Pieris rapae crucivora, accept and mate with courting males, whereas mated females reject them and assume the “mate refusal posture”. This study tested whether the biogenic amines, serotonin (5HT), dopamine (DA), and octopamine (OA), were responsible for this change in behavior. The results showed that 2–3-day-old virgin females fed with 5HT rejected courting males significantly more frequently compared with controls fed on sucrose. In contrast, the proportions of courting males rejected by virgin females fed with either DA or OA did not differ from sucrose-fed controls. Oral application of each amine resulted in significantly increased levels of the amine applied (or its metabolite) in the brain. The results strongly suggest that 5HT or a 5HT metabolite may be responsible for the post-mating change in behavioral response of 2–3-day-old virgin females to courting males. Similar effects of 5HT treatment were observed in 6–8-day-old virgin females, but in this case the results were only marginally different from the controls, suggesting that the effect may decline with increasing female age.  相似文献   
108.
要获得有意义的温室气体清单,重要的是清单中包括的内容的方法论和定义应该是一致的.国际石油工业环境保护协会(IPIECA)、国际石油和天然气生产者协会(OGP)以及美国石油学会(API)已经制定了温室气体排放计算和报告的准则.国际石油工业环境保护协会(IPITCA)报告温室气体排放的石油工业指南的重点是放在石油工业温室气体排放的计算和报告上.为了提供排放估算一致的方法论,美国石油工业协会制定了石油和天然气工业温室气体排放估算方法论概要.从美国石油学会可以得到一个估算排放的工具--SANGEATM能源和排放估算系统.  相似文献   
109.
Buckwheat tea waste (BWTW) and barley tea waste (BTW), by-products of the beverage industry, are alternative carbohydrate sources for ethanol production. In this study, optimal enzyme loading for enzymatic saccharification of BWTW and BTW was determined, and simultaneous saccharification and fermentation (SSF) was performed by Saccharomyces cerevisiae and Mucor indicus to produce ethanol. Optimal enzyme loading for enzymatic saccharification of 2?% w/v BWTW and BTW was 0.5?% (weight of enzyme/weight of tea wastes) for BWTW and 0.1?% for BTW. Ethanol production from BWTW by S. cerevisiae and M. indicus after 48?h of SSF was 49.9/100?g of BWTW and 47.9/100?g of BWTW, respectively, with 0.5?% enzyme loading. Ethanol production from BTW by S. cerevisiae and M. indicus after 48?h of SSF was 20.5/100?g of BTW and 21.6/100?g of BTW, corresponding to 62 and 66?% of the theoretical yield based on starch content, respectively, with 0.1?% of enzyme loading. Furthermore, S. cerevisiae produced 76?% of the theoretical yield based on the total glucose from starch in BWTW and BTW when a mixture of BWTW and BTW was used as a substrate, with 0.2?% enzyme loading and no additional nitrogen or mineral sources.  相似文献   
110.
How simple can a model be that still captures essential aspects of wildfire ecosystems at large spatial and temporal scales? The Drossel-Schwabl model (DSM) is a metaphorical forest-fire model developed to reproduce only one pattern of real systems: a frequency distribution of fire sizes resembling a power law. Consequently, and because it appears oversimplified, it remains unclear what bearings the DSM has in reality. Here, we test whether the DSM is capable of reproducing a pattern that was not considered in its design, the hump-shaped relation between the diversity of succession stages and average annual area burnt. We found that the model, once reformulated to represent succession, produces realistic landscape diversity patterns. We investigated four succession scenarios of forest-fire ecosystems in the USA and Canada. In all scenarios, landscape diversity is highest at an intermediate average annual area burnt as predicted by the intermediate disturbance hypothesis. These results show that a model based solely on the dynamics of the fuel mosaic has surprisingly high predictive power with regard to observed statistical properties of wildfire systems at large spatial scales. Parsimonious models, such as the DSM can be used as starting points for systematic development of more structurally realistic but tractable wildfire models. Due to their simplicity they allow analytical approaches that further our understanding under increasing complexity.  相似文献   
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