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141.
We describe a model of forest flammability, based on daily satellite observations, for national to regional applications. The model defines forest flammability as the percent moisture content of fuel, in the form of litter of varying sizes on the forest floor. The model uses formulas from the US Forest Service that describe moisture exchange between fuel and the surrounding air and precipitation. The model is driven by estimates of temperature, humidity, and precipitation from the moderate resolution imaging spectrometer and tropical rainfall measuring mission multi-satellite precipitation analysis. We provide model results for the southern Amazon and northern Chaco regions. We evaluate the model in a tropical forest-to-woodland gradient in lowland Bolivia. Results from the model are significantly correlated with those from the same model driven by field climate measurements. This model can be run in a near real-time mode, can be applied to other regions, and can be a cost-effective input to national fire management programs.  相似文献   
142.
Labeling of food consumption is related to food safety, food quality, environmental, safety, and social concerns. Future politics of food will be based on a redefinition of commodity food consumption as an expression of citizenship. “Citizen-consumers” realize that they could use their buying power in order to develop a new terrain of social agency and political action. It takes for granted kinds of moral selfhood in which human responsibility is bound into human agency based on knowledge and recognition. This requires new kinds of food labeling practices. Existing research on consumer’s preferences often fails to recognize the full complexity of the motivations and intentions through which the identity of the moral self is built up in relation to food consumption practices. For citizens, not only food production practices matter but also the impact of what we eat on who we are and the ecological foot print of our food stuff. Two major drivers for this are the idea that we ourselves have to take care of our own bodies (“We are what we eat”) and that we are responsible for Planet Earth. Since both obesity and climate change have become major public concerns, also governments develop an increasing interest in defining how citizens ought to behave as consumers and how retailers and producers should facilitate such responsible behavior. Since they are supposed to defend the “bonum commune,” e.g., the public health of their citizens and a sound common future for all, a new consensus on “appropriate” consumption choices has to be found, balancing beneficence and autonomy.  相似文献   
143.
本文采用让受访问者做选择题的办法,研究来自农业的食品品质特性与消费者支付意愿的关系,目前这些食品在瑞典还没有销售.数据是通过大规模的邮件调查获得的,同时用一个随机参数的Logit模型来估计.我们的结果表明:同一产品和相同特性,消费者的支付意愿均存在差异.不同产品间为品质特性排序时也是这样.而且,我们还发现可能以转基因作物作为饲料的动物食品市场上表现不力.最后,我们的结论支持被称作"cheap-talk"的研究方法能有效地减小选择试验地的外在误差.在食品行业中,我们的结论对产品差别化战略的构建和对食品政策的形成等方面十分有用.  相似文献   
144.
The Mekong River’s natural resources offer large benefits to its populations, but it also attracts the interest of foreign investors. Recently, Chinese firms, banks and government bodies have increasingly invested in large hydropower projects in the Greater Mekong Sub-Region. Due to China’s rapid economic growth, its rapid industrialisation and its limited domestic natural resources, the Chinese government has issued the ‘Going Out Strategy’ which promotes investments in overseas natural resources like water and energy resources. In search for climate-friendly low-carbon energy, cheap electricity and access to a growing market, Chinese institutions turn to Southeast Asia where Chinese institutions are currently involved in more than 50 on-going large hydropower projects as contractors, investors, regulators and financiers. These Chinese institutions have influence on environmental and social practices as well as on diplomatic and trade relations in the host countries. Currently, there are major gaps in understanding who is engaged, why, how and with what impacts. This paper therefore aims to assess the motives, actors, beneficiaries and the direct and indirect impacts of China’s investment in large hydropower projects in the Greater Mekong Sub-Region. The authors use the ‘Rising Powers Framework’ to assess these issues, which is an adapted version of the Asian Drivers Framework.  相似文献   
145.
Attitudes of Dutch Pig Farmers Towards Tail Biting and Tail Docking   总被引:1,自引:1,他引:0  
The Dutch policy objective of a fully sustainable livestock sector without mutilations by 2023 is not compatible with the routine practice of tail docking to minimize the risk of tail biting. To examine farmer attitudes towards docking, a telephone survey was conducted among 487 conventional and 33 organic Dutch pig farmers. “Biting” (of tails, ears, or limbs) was identified by the farmers as a main welfare problem in pig farming. About half of the farmers reported to have no tail biting problems in their own herd. When farmers did report problems, they most often reported figures between 1 and 5 % of the animals. High incidences of tail biting were anticipated when trying to keep undocked pigs. Enrichment materials used in the conventional sector included mainly chains (52–63 % of the farms) and hanging rubber or plastic balls (22–30 %). Straw, sawdust, or wood shavings was hardly provided in conventional pig farming (2–3 %), in contrast to organic farming (88–100 % of farms). Conventional pig farmers feel a curly tail is not very important for sustainable pig farming. They consider enrichment to be less effective and tail docking to be less stressful for them and their piglets than their organic colleagues do. Pig farmers identified climate as a main risk factor for tail biting as opposed to enrichment. The objective of reducing routine tail docking requires solutions for dealing with tail biting problems at the farm level. In this process, transfer of scientific knowledge about enrichment materials and other measures to prevent and cure tail biting is critical, as is a change in farmer attitudes and awareness of the moral issues involved.  相似文献   
146.
Climate change is an important new challenge for local authorities. This study analyses the potential for using the Swedish mandatory process for risk and vulnerability analysis (RVA) as a vehicle to improve local climate adaptation work. An advantage with RVA is its comprehensive approach in dealing with all relevant threats and all vital functions of society. In order to test the applicability of incorporating climate adaptation into RVA, we studied practical experiences from three Swedish municipalities. In all municipalities, a pre-study to identify relevant climate-induced events was performed. In one municipality, this was followed by a more detailed analysis of the potential impacts of these events on the functions of the various administrations and companies within the local authority. Problems identified in successful integration of climate change into the municipal RVA process were lack of sufficient knowledge to identify the impacts of climate change on the level of the respective specialist or district administration and lack of resources to perform the analysis. There were also some difficulties in including a long-term perspective relevant for climate adaptation into RVA, which usually focuses on current threats. A positive outcome was that work on extreme climate events in RVA provided a traceable method to identify events with a potentially great impact on the function of local society and results that could be fed into other ongoing processes, such as spatial planning and housing plans.  相似文献   
147.
OBJECTIVES: The present study examined the influence of age on the morbidity and mortality of pedestrian victims while controlling for confounding factors. METHODS: The Pedestrian Crash Data Study (PCDS) database was used for a cross-sectional study to compare the outcome of senior (age >or=60 years) and adult (age 19 to 50 years) pedestrian victims. The outcome measures were the Injury Severity Score (ISS), Maximum Abbreviated Injury Score (MAIS), Abbreviated Injury Scale (AIS), and Mortality. Logistic regression models were used to estimate age-associated risks while controlling for confounders such as vehicle type, impact speed, and pedestrian height, weight, and gender. RESULTS: Compared to the adult victims, the seniors had a higher average ISS (23 vs. 16, p = 0.018) and higher mortality (30 percent vs. 11 percent, p or=9 (odds ratio = 2.72; 95 percent CI: 1.31-5.68) and to die (odds ratio = 6.68; 95 percent CI: 2.37-19.88). The seniors were approximately twice as likely to have higher AIS scores to almost every body region. CONCLUSIONS: The adjusted age-dependent risks indicated by the current study should be considered when calculating or projecting pedestrian morbidity and mortality. Adjustment in statistical models is essential to achieve precise risk estimates and in turn to appropriately allocate public health rescores.  相似文献   
148.
An ecological impact study was performed based on in situ biomarker assays with the waterflea Daphnia magna. The effects of metallurgic effluents on the energy metabolism, anti-oxidative metabolism and DNA damage were assessed in caged daphnids during a 4-week study. In situ survival and reproduction studies demonstrated a clear impact on these parameters in organisms exposed in the most polluted areas. At the downstream--sublethal--zone the organisms were disturbed within their tolerance limits, resulting in alterations of their energy metabolism. These data suggest an acclimation hypothesis, which was tested through the analysis of the energy metabolism of resident species: isopods and amphipods. These organisms had shifted to a decrease in their overall energy metabolism compared to the upstream region. This change in some biochemical processes suggests a selective advantage to cope with the prevailing environmental conditions. In addition, we found clear genotoxic effects caused by the industrial discharges that might correlate with a reduction in (long-term) survival.  相似文献   
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