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661.
Protected areas (PAs) and payments for ecosystem services (PES) are the top two mechanisms available for countries to achieve international REDD agreements, yet there are few empirical comparisons of their effects. We estimate the impacts of PAs and PES on forest conservation, poverty reduction, and population change at the locality level in Mexico in the 2000s. Both policies conserved forest, generating an approximately 20–25% reduction in expected forest cover loss. PES created statistically significant but small poverty alleviation while PAs had overall neutral impacts on livelihoods. Estimates by individual policy type for the same level of deforestation risk indicate that biosphere reserves and PES balanced conservation and livelihood goals better than strict protected areas or mixed-use areas. This suggests that both direct and incentive-based instruments can be effective, and that policies combining sustainable financing, flexible zoning, and recognition of local economic goals are more likely to achieve conservation without harming livelihoods.  相似文献   
662.
Subsistence hunting presents a conservation challenge by which biodiversity preservation must be balanced with safeguarding of human livelihoods. Globally, subsistence hunting threatens primate populations, including Madagascar's endemic lemurs. We used population viability analysis to assess the sustainability of lemur hunting in Makira Natural Park, Madagascar. We identified trends in seasonal hunting of 11 Makira lemur species from household interview data, estimated local lemur densities in populations adjacent to focal villages via transect surveys, and quantified extinction vulnerability for these populations based on species-specific demographic parameters and empirically derived hunting rates. We compared stage-based Lefkovitch with periodic Leslie matrices to evaluate the impact of regional dispersal on persistence trajectories and explored the consequences of perturbations to the timing of peak hunting relative to the lemur birth pulse, under assumptions of density-dependent reproductive compensation. Lemur hunting peaked during the fruit-abundant wet season (March–June). Estimated local lemur densities were roughly inverse to body size across our study area. Life-history modeling indicated that hunting most severely threatened the species with the largest bodies (i.e., Hapalemur occidentalis, Avahi laniger, Daubentonia madagascariensis, and Indri indi), characterized by late-age reproductive onsets and long interbirth intervals. In model simulations, lemur dispersal within a regional metapopulation buffered extinction threats when a majority of local sites supported growth rates above the replacement level but drove regional extirpations when most local sites were overharvested. Hunt simulations were most detrimental when timed to overlap lemur births (a reality for D. madagascariensis and I. indri). In sum, Makira lemurs were overharvested. Regional extirpations, which may contribute to broad-scale extinctions, will be likely if current hunting rates persist. Cessation of anthropogenic lemur harvest is a conservation priority, and development programs are needed to help communities switch from wildlife consumption to domestic protein alternatives.  相似文献   
663.
• Isotope dilution method was developed for the determination of 27 PPCPs in water. • The established method was successfully applied to different types of water samples. • The correction effect of corresponding 27 ILSs over 70 d was investigated. • Benefit of isotopic dilution method was illustrated for three examples. Pharmaceuticals and personal care products (PPCPs) are a unique group of emerging and non-persistent contaminants. In this study, 27 PPCPs in various water samples were extracted by solid phase extraction (SPE), and determined by isotope dilution method using liquid chromatography coupled to tandem triple quadruple mass spectrometer (LC-MS/MS). A total of 27 isotopically labeled standards (ILSs) were applied to correct the concentration of PPCPs in spiked ultrapure water, drinking water, river, effluent and influent sewage. The corrected recoveries were 73%–122% with the relative standard deviation (RSD)<16%, except for acetaminophen. The matrix effect for all kinds of water samples was<22% and the method quantitation limits (MQLs) were 0.45–8.6 ng/L. The developed method was successfully applied on environmental water samples. The SPE extracts of spiked ultrapure water, drinking water, river and wastewater effluent were stored for 70 days, and the ILSs-corrected recoveries of 27 PPCPs were obtained to evaluate the correction ability of ILSs in the presence of variety interferences. The recoveries of 27 PPCPs over 70 days were within the scope of 72%–140% with the recovery variation<37% in all cases. The isotope dilution method seems to be of benefit when the extract has to be stored for long time before the instrument analysis.  相似文献   
664.
In the Anthropocene, coupled human and natural systems dominate and only a few natural systems remain relatively unaffected by human influence. On the one hand, conservation criteria based on areas of minimal human impact are not relevant to much of the biosphere. On the other hand, conservation criteria based on economic factors are problematic with respect to their ability to arrive at operational indicators of well‐being that can be applied in practice over multiple generations. Coupled human and natural systems are subject to economic development which, under current management structures, tends to affect natural systems and cross planetary boundaries. Hence, designing and applying conservation criteria applicable in real‐world systems where human and natural systems need to interact and sustainably coexist is essential. By recognizing the criticality of satisfying basic needs as well as the great uncertainty over the needs and preferences of future generations, we sought to incorporate conservation criteria based on minimal human impact into economic evaluation. These criteria require the conservation of environmental conditions such that the opportunity for intergenerational welfare optimization is maintained. Toward this end, we propose the integration of ecological–biological thresholds into decision making and use as an example the planetary‐boundaries approach. Both conservation scientists and economists must be involved in defining operational ecological–biological thresholds that can be incorporated into economic thinking and reflect the objectives of conservation, sustainability, and intergenerational welfare optimization.  相似文献   
665.
IntroductionWith the development of industries and increased diversity of their associated hazards, the importance of identifying these hazards and controlling the Occupational Health and Safety (OHS) risks has also dramatically augmented. Currently, there is a serious need for a risk management system to identify and prioritize risks with the aim of providing corrective/preventive measures to minimize the negative consequences of OHS risks. In fact, this system can help the protection of employees’ health and reduction of organizational costs. Method: The present study proposes a hybrid decision-making approach based on the Failure Mode and Effect Analysis (FMEA), Fuzzy Cognitive Map (FCM), and Multi-Objective Optimization on the basis of Ratio Analysis (MOORA) for assessing and prioritizing OHS risks. After identifying the risks and determining the values of the risk assessment criteria via the FMEA technique, the attempt is made to determine the weights of criteria based on their causal relationships through FCM and the hybrid learning algorithm. Then, the risk prioritization is carried out using the MOORA method based on the decision matrix (the output of the FMEA) and the weights of the criteria (the output of the FCM). Results: The results from the implementation of the proposed approach in a manufacturing company reveal that the score at issue can overcome some of the drawbacks of the traditional Risk Priority Number (RPN) in the conventional FMEA, including lack of assignment the different relative importance to the assessment criteria, inability to take into account other important management criteria, lack of consideration of causal relationships among criteria, and high dependence of the prioritization on the experts’ opinions, which finally provides a full and distinct risk prioritization.  相似文献   
666.
氢能具有储运便捷、来源多样、洁净环保等突出优点,许多国家把发展氢能作为重要的能源战略。氢安全是氢能大规模商业化应用的重要保障。在分析国内外氢安全领域近年来最新研究进展的基础上,依次从氢泄漏与扩散、氢燃烧与爆炸、氢与金属材料相容性及氢风险评价等方面,系统总结了国内外氢安全研究面临的挑战,并对我国氢安全的发展提出了建议。  相似文献   
667.
主要根据客户要求,在低速(1 km/h)及轻载工况下,测量传动端轴承无飞溅润滑条件下的温升等参数,而进行相关的电机试验,为某型机车牵引电机传动端轴承在低速及轻载工况下,无飞溅润滑提供试验验证及技术支撑。  相似文献   
668.
平原河网地区非点源污染风险差异化分区防控研究   总被引:1,自引:0,他引:1  
土地利用优化和空间防控策略对非点源污染风险控制及水环境质量的改善具有重要意义。本文以太湖流域典型平原河网地区-上海市青浦区为研究对象,将灰色线性规划模型与最小累积阻力模型相结合,以控制非点源污染风险和增加经济效益、生态效益为目标,进行土地利用结构优化与空间分区防控研究,在空间上划设了水资源保育区、水资源重点防护区、非点源污染一般阻控区、非点源污染中等阻控区及非点源污染重点阻控区,并针对不同分区提出具有针对性的防控措施。与2012年相比,预测2020年优化防控方案下,可减少总氮、总磷的输出10.96%和41.33%。由此表明,优化土地利用结构和构建空间差异化防控机制是有效调控非点源污染风险,实现区域可持续土地利用,促进经济发展和保证生态环境安全的有效途径。  相似文献   
669.
The continuously increasing solid waste generation worldwide calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, life cycle assessment (LCA) is a tool, which can contribute to answer that call. But how, where and to which extent has it been applied to solid waste management systems (SWMSs) until now, and which lessons can be learnt from the findings of these LCA applications? To address these questions, we performed a critical review of 222 published LCA studies of SWMS. We first analysed the geographic distribution and found that the published studies have primarily been concentrated in Europe with little application in developing countries. In terms of technological coverage, they have largely overlooked application of LCA to waste prevention activities and to relevant waste types apart from household waste, e.g. construction and demolition waste. Waste management practitioners are thus encouraged to abridge these gaps in future applications of LCA. In addition to this contextual analysis, we also evaluated the findings of selected studies of good quality and found that there is little agreement in the conclusions among them. The strong dependence of each SWMS on local conditions, such as waste composition or energy system, prevents a meaningful generalisation of the LCA results as we find it in the waste hierarchy. We therefore recommend stakeholders in solid waste management to regard LCA as a tool, which, by its ability of capturing the local specific conditions in the modelling of environmental impacts and benefits of a SWMS, allows identifying critical problems and proposing improvement options adapted to the local specificities.  相似文献   
670.
The co-digestion of a variable amount of fruit and vegetable waste in a waste mixed sludge digester was investigated using a pilot scale apparatus. The organic loading rate (OLR) was increased from 1.46 kg VS/m3 day to 2.8 kg VS/m3 day. The hydraulic retention time was reduced from 14 days to about 10 days. Specific bio-methane production increased from about 90 NL/kg VS to the maximum value of about 430 NL/kg VS when OLR was increased from 1.46 kg VS/m3 day to 2.1 kg VS/m3 day. A higher OLR caused an excessive reduction in the hydraulic retention time, enhancing microorganism wash out. Process stability evaluated by the total volatile fatty acids concentration (mg/l) to the alkalinity buffer capacity (eq. mg/l CaCO3) ratio (i.e. FOS/TAC) criterion was <0.1 indicating high stability for OLR <2.46 kg VS/m3 day. For higher OLR, FOS/TAC increased rapidly. Residual phytotoxicty of the digestate evaluated by the germination index (GI) (%) was quite constant for OLR < 2.46 kg VS/m3 day, which is lower than the 60% limit, indicating an acceptable toxicity level for crops. For OLR > 2.46 kg VS/m3 day, GI decreased rapidly. This corresponding trend between FOS/TAC and GI was further investigated by the definition of the GI ratio (GIR) parameter. Comparison between GIR and FOS/TAC suggests that GI could be a suitable criterion for evaluating process stability.  相似文献   
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