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71.
In this paper, we present and defend the theoretical framework of an empirical model to describe people’s fundamental moral attitudes (FMAs) to animals, the stratification of FMAs in society and the role of FMAs in judgment on the culling of healthy animals in an animal disease epidemic. We used philosophical animal ethics theories to understand the moral basis of FMA convictions. Moreover, these theories provide us with a moral language for communication between animal ethics, FMAs, and public debates. We defend that FMA is a two-layered concept. The first layer consists of deeply felt convictions about animals. The second layer consists of convictions derived from the first layer to serve as arguments in a debate on animal issues. In a debate, the latter convictions are variable, depending on the animal issue in a specific context, time, and place. This variability facilitates finding common ground in an animal issue between actors with opposing convictions.  相似文献   
72.
畜牧业“碳排放”到“碳足迹”核算方法的研究进展   总被引:1,自引:0,他引:1  
全球变暖趋势日益加剧,不仅影响农业可持续发展,而且威胁到人类生存。畜牧业碳排放因其在农业碳排放中乃至全球碳排放中占比较大而日益备受关注。准确核算畜牧业碳排放是制定切实可行的碳减排政策的前提,也为我国在气候变化下承担共同但有差别的减排责任提供话语权。本文基于研究范式的演进,对畜牧业碳排放到碳足迹核算方法的研究发展进行了系统梳理,研究表明,在学者的不断研究与质疑下,畜牧业碳排放到碳足迹的核算方法经历了从OECD核算法、IPCC系数法到生命周期法与投入-产出法的演变与完善,学术界认为区域异质性、养殖规模与管理方式均影响碳足迹;散养比规模化养殖产生更多的碳排放,舍饲比户外放牧排放更多的碳。畜牧业碳足迹核算能够更加全面地反映畜牧业全生命周期的碳排放情况,但由于研究假设、研究方法及研究样本等差异导致不同区域、不同畜产品的碳排放核算结果存在不确定性。运用生命周期法和投入-产出法对欧盟成员国畜牧业碳排放的核算结果基本一致,但运用IPCC系数法和全生命周期法对中国畜牧业碳排放核算中,牛、猪和羊的碳排放量排序结果不尽一致。鉴于核算结果的差异性,本研究对不同核算方法的起源、最早采用时间、特点、局限性等方面进行了归纳总结,并建议后续研究探讨基于生命周期评价的畜牧业碳足迹研究边界的延伸性,标准化畜牧业碳排放或碳足迹核算,避免学者重复核算畜牧业碳排放,以便深入展开畜牧业碳排放其他方面的研究。  相似文献   
73.
The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing.  相似文献   
74.
Verma V  Yu QJ  Connell DW 《Chemosphere》2012,89(9):1026-1033
Traditionally in toxicological studies time is not studied as quantifiable variable but as a fixed endpoint. The Reduced Life Expectancy (RLE) model which relates exposure time and exposure concentration with lethal toxic effects was tested previously using fish data. In this current paper the effects of exposure time on aquatic toxicity with zooplanktons and various toxicants were evaluated using the RLE model based on ambient exposure concentration. The model was evaluated by plotting ln LT50 against LC50 using toxicity data with zooplanktons from the literature for metal, metalloid and organic compounds. Most of the experimental data sets can be satisfactorily correlated by use of the RLE model, but deviations occurred for some data sets. Those data sets were satisfactorily fitted by a two stage RLE model. This model was based on two phases: one in the peripheral system and other in the central system. Both the single and two stage RLE model support the hypothesis that toxicity is time dependent and decreases in a systematic way with increasing exposure time. A calculated normal life expectancy (NLT) can be obtained from the single stage model and is in accord with reported NLT but those obtained from the two stage RLE model are in excellent agreement.  相似文献   
75.
加速寿命试验与高加速寿命试验的比较分析   总被引:4,自引:3,他引:1  
介绍了加速寿命试验、高加速寿命试验的基本概念、原理,从试验目的、试验方法、试验时间等方面对加速寿命试验和高加速寿命试验进行了比较,说明它们有不同的应用时机和范围.加速寿命试验、高加速寿命试验都是卓越的加速环境试验技术,也是可靠性试验领域的两个主要发展方向.  相似文献   
76.
Increased salinity in spawning and nursery grounds in the Savannah River estuary was cited as the primary cause of a 97% decrease in adult striped bass (Morone saxatilis) and a concomitant 96% decrease in striped bass egg production. Restoration efforts focused on environmental remediation and stock enhancement have resulted in restored salinity patterns and increased egg and adult abundances. However, future water needs or harbor development may preclude further recovery by reducing freshwater inflow or increasing salinity intrusion. To assess the effect of potential changes in the salinity regime, we developed models relating discharge, tidal phase, and salinity to striped bass egg and early larval survival and re-cast these in a quantitative Bayesian belief network. The model indicated that a small upstream shift (≤1.67 km) in the salinity regime would have the least impact on striped bass early life history survival, whereas shifts >1.67 km would have progressively larger impacts, with a 8.33-km shift potentially reducing our estimated survival probability by >28%. Such an impact could have cumulative and long-term detrimental effects on the recovery of the Savannah River striped bass population. The available salinity data were collected during average and low flows, so our model represents some typical and some extreme conditions during a striped bass spawning season. Our model is a relatively simplistic, “first-order” attempt at evaluating potential effects of changes in the Savannah River estuarine salinity regime and points to areas of concern and potential future research.  相似文献   
77.
Abstract: Loss of human stability in flood flows and consequent drowning are a high personal hazard. In this paper, we review past experimental work on human instability. The results of new experiments by the Flood Hazard Research Centre (FHRC) are also reported. These new results show that low depth/high velocity flood waters are more dangerous than suggested based on previous experimental work. It is discussed how human instability can be related to two physical mechanisms: moment instability (toppling) and friction instability (sliding). Comparison of the test results with these physical mechanisms suggests that the occurrence of instability in the tests by FHRC is related to friction instability. This mechanism appears to occur earlier than moment instability for the combination of shallow depth and high flow velocity. Those concerned to identify locations where high flood flows could be a threat to human life need to modify their hazard assessments accordingly.  相似文献   
78.
兰州大石鸡不同生活史阶段栖息地选择的初步研究   总被引:8,自引:0,他引:8  
大石鸡不同生活史阶段选择不同的栖息地.集群期选择坡度小、低海拔、东向的山坡和坟地.配对期选择坡度30~60°、海拔居中的栖息地,选择的栖息地范围较宽.产卵期多见于坡度小、地面环境异质性小、海拔高的农田和山坡.育雏期选择植物丛密度低、坡度小、海拔高的山坡和农田.繁殖后期选择植物丛密度低、低海拔、东向的山坡和沟底.不同生活史阶段植被覆盖度、植物高度、环境类型和坡向差异不显著,坡度差异显著,植物丛密度、海拔高度和地面环境异质性差异极显著.在各环境因子中,只有地面环境异质性对大石鸡栖息地选择的影响较显著.地形、食物和气候可能是影响大石鸡栖息地选择的根本因素.  相似文献   
79.
新能源汽车替代传统燃油车是减缓能源与环境压力并如期实现“双碳”目标的重要途径,但在重型车辆、工程车等领域推广较为缓慢.深圳市自2019年开始推广使用纯电动泥头车,并计划到2025年新能源环卫、泥头车数量达到8000辆.为深入探究纯电动泥头车替代柴油泥头车所产生的减污降碳协同效益,本研究基于一手调研数据,采用生命周期评价方法并结合GREET模型,对比分析了两类泥头车在燃料周期、车辆周期和配套设施周期3个周期内的能耗、主要空气污染物及碳排放情况.结果表明,纯电动泥头车全生命周期内能耗较柴油泥头车可减少36.2%,主要污染物如NOx、SO2、VOC和PM2.5降幅分别达81.3%、37.8%、29.0%和25.9%;温室气体(GHGs)排放强度减少14.4%,基准情境下2030年和2050年推广纯电动泥头车GHGs累计减排量分别为71.4万t和258.5万t.尽管节能减排效果显著,但其初始购置和售后维保成本过高是制约其推广的最主要因素,通过降低车辆及电池生产制造成本、提高充换电设施数量及售后维保能力等有望加快泥头车纯电动化.  相似文献   
80.
Insects that should be considered for conservation attention are often overlooked because of a lack of data. The detailed information necessary to assess population growth, decline, and maximum range is particularly difficult to acquire for rare and cryptic species. Many of these difficulties can be overcome with the use of life table analyses and heat energy accumulation models common in agriculture. The wekiu bug (Nysius wekiuicola), endemic to the summit of one volcanic mountain in Hawaii, is a rare insect living in an environmentally sensitive alpine stone desert, where field‐based population assessments would be inefficient or potentially detrimental to natural and cultural resources. We conducted laboratory experiments with the insects by manipulating rearing temperatures of laboratory colonies and made detailed observations of habitat conditions to develop life tables representing population growth parameters and environmental models for wekiu bug phenology and demographic change. Wekiu bugs developed at temperatures only found in its environment on sunny days and required the thermal buffer found on cinder cones for growth and population increase. Wekiu bugs required approximately 3.5 months to complete one generation. The bug developed optimally from 26 to 30 °C, temperatures that are much higher than the air temperature attains in its elevational range. The developmental temperature range of the species confirmed a physiological reason why the wekiu bug is only found on cinder cones. This physiology information can help guide population monitoring and inform habitat restoration and conservation. The wekiu bug was a candidate for listing under the U.S. Endangered Species Act, and the developmental parameters we quantified were used to determine the species would not be listed as endangered or threatened. The use of developmental threshold experiments, life table analyses, and degree day modeling can directly inform otherwise unobservable habitat needs and demographic characteristics of extremely rare insects. Aplicación de Análisis Demográfico de Desarrollo Agrícola para la Conservación del Insecto Weiku Alpino Hawaiano  相似文献   
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