Developing farm-specific marginal abatement cost curves: Cost-effective greenhouse gas mitigation opportunities in sheep farming systems

Growing demand for agricultural produce, coupled with ambitious targets for greenhouse gas emissions reduction present the scientific, policy and agricultural sectors with a substantial mitigation challenge. Identification and implementation of suitable mitigation measures is driven by both the measures’ effectiveness and cost of implementation. Marginal abatement cost curves (MACCs) provide a simple graphical representation of the abatement potential and cost-effectiveness of mitigation measures to aid policy decision-making. Accounting for heterogeneity in farm conditions and subsequent abatement potentials in mitigation policy is problematic, and may be aided by the development of tailored MACCs. Robust MACC development is currently lacking for mitigation measures appropriate to sheep systems. This study constructed farm-specific MACCs for a lowland, upland and hill sheep farm in the UK. The stand-alone mitigation potential of six measures was modelled, against real farm baselines, according to assumed impacts on emissions and productivity. The MACCs revealed the potential for negative cost emissions’ abatement in the sheep industry. Improving ewe nutrition to increase lamb survival offered considerable abatement potential at a negative cost to the farmers across all farms while, lambing as yearlings offered negative cost abatement potential on lowland and upland farms. The results broadly advocate maximising lamb output from existing inputs on all farm categories, and highlight the importance of productivity and efficiency as influential drivers of emissions abatement in the sector. The abatement potentials and marginal costs of other measures (e.g. reducing mineral fertiliser use and selecting pasture plants bred to minimise dietary nitrogen losses) varied between farms, and this heterogeneity was more frequently attributable to differences in individual farm management than land classification. This has important implications for the high level policy sector as no two farms are likely to benefit from a generic one size fits all approach to mitigation. The construction of further case-study farm MACCs under varying farm conditions is required to define the biophysical and management conditions that each measure is most suited to, generating a more tailored set of sector-specific mitigation parameters.     

脂松引种的初步研究

利用数理统计方法,通过分析试验中得到的数据,讨论了脂松在黑龙江省城市引种的抚育管理技术,并分析了它的生长规律。     

含孔洞红砂岩破坏机理的离散元研究

含孔洞岩石破坏具有非连续、大变形的特点,离散元方法能真实反映岩石内部存在的微裂隙、断层、节理等缺陷,并能分析计算岩石破坏中的大变形情况。使用PFC软件建立红砂岩的离散元模型,研究单、双向应力情况下含孔洞红砂岩试件的破坏过程,分析含孔洞红砂岩的破坏机理。研究表明：与完整红砂岩试件相比,含孔洞红砂岩试件的峰值应力明显下降,峰值应力降低的程度与孔洞的形状（圆形、方形、马蹄形）相关;随着围压水平的提高,含孔洞红砂岩破坏峰值应力逐渐增大,且围压限制了初始拉伸裂纹的扩展,其最终的破坏形式与单轴压缩形式相似。     

钼酸钙红色荧光粉制备及性能研究

文章介绍采用溶胶-凝胶法合成可用于395nm及465nm激发的Ca1-2xBxEuxMoO4（B=Li^＋,Na^＋,K^＋）红色荧光粉。用粉末X射线衍射（XRD）和荧光光谱对其结构、发光性能进行了表征,并就不同电荷补偿对其发光性能的影响进行了分析。同时,详细研究了煅烧温度及Eu^3＋离子浓度对所得荧光粉的发光性能的影响。     

陕甘宁红色旅游流的网络结构特征研究

开展陕甘宁红色旅游流网络结构特征研究,可以指导目的地旅游网络结构优化,推动红色旅游高质量发展。运用GIS技术、社会网络分析等方法,对陕甘宁红色旅游流整体网络特征、网络节点特征进行系统研究。结果表明,陕甘宁红色旅游流网络结构松散,密度低,呈现典型的“核心-边缘”特征;红色旅游流网络凝聚特征显著,地域集中性强,跨区域合作有待强化;延安革命纪念馆等关键节点功能地位突出,网络极化效应显著;核心节点对周边节点存在“虹吸效应”。研究进一步从构建多极化红色旅游流网络体系、推动红色旅游与相关业态协调发展和创新融合等方面就推动陕甘宁红色旅游流网络优化提出了相关对策建议。     

国内红色旅游资源开发战略研究--以福建省为例

我国红色旅游资源十分丰富,但大部分还处于待开发阶段.为了促进我国红色旅游产业的健康发展,本文以福建省为例,探讨了国内红色旅游资源开发中必须注意的几个战略问题:第一,经济效益与社会效益兼顾;第二,科学合理的调查研究与保护红色旅游资源;第三,明确开发层次与开发重点;第四,注意选择科学合理的开发方式,避免破坏资源和浪费投资;第五,重视区域旅游合作开发.     

关于红色旅游资源的安全性研究

作为一种新型的旅游载体,红色旅游资源是红色旅游区别于其他特色旅游的重要标志之一,其开发潜力是巨大的。但是,目前这种新型旅游载体的安全状况却不容乐观。在界定红色旅游资源的概念、分析红色旅游资源的特点、探讨红色旅游资源面临不安全状况的原因的基础上,提出了加强红色旅游资源安全保护的对策。     

内蒙古地区城镇居民肉类消费需求研究

本文以具有典型内陆消费特点的内蒙古地区为例,通过构建修正的AIDS模型即LA/AIDS模型和扩展的LES模型即ELES模型,利用2000年到2011年内蒙古城镇居民肉类消费的时间序列数据,对该地区城镇居民消费结构的变化趋势进行了实证分析。结果表明：当收入增加时,人们会更多的消费羊肉和牛肉,在考虑价格因素后,猪、牛、羊、鸡四种主要肉类消费支出份额趋于平衡;牛羊肉自价格弹性绝对值较大,但四种肉类都属于生活必需品。     

Even beyond humanity – a comment on ‘Change and commitment: beyond risk and responsibility’ by Silvio Funtowicz and Roger Strand

Due to past major food scares, food-safety perceptions have become a widely investigated topic. The aim of the present study was to examine food-safety perceptions separately for every step of the total meat supply chain, as such a detailed approach yields more promising strategies to ensure food safety in the future. Using a large-scale survey, we examined people’s risk perceptions of 18 steps describing the total meat supply chain. The results revealed a clear distinction between risk perception at the production stage and risk perception at home in the total meat supply chain, in that people perceived significantly less risk at home. However, people’s risk perceptions of the single stages in the total meat supply chain were overall slightly above average. Additionally, there were individual differences, as risk perception at the production stage was highly correlated with risk perception at home, meaning that some people perceived more risk than others overall. Using a multiple regression analysis, we found food-safety perceptions to be barely significant next to other important variables affecting people’s meat-consumption decisions. For those analyses, we asked participants to assess several constructs previously found to be associated with meat consumption. The goal was to determine how food-safety perceptions influence people’s meat consumption next to other important constructs in situations in which no major food scandal is present. The present paper concludes by discussing possible marketing and policy strategies to overcome people’s inaccurate safety perceptions of the stages of the total food chain.     

中国自然保护地体系建设——红线管控、旅游发展与文化表征

建立以国家公园为主体的自然保护地体系,是贯彻习近平生态文明思想的重大举措,是党的十九大提出的重大改革任务。有效协调自然保护地保护与开发的功能定位是实现“生态保护、绿色发展、改善民生”三效合一目标的难点与重点。本文围绕如何有效发挥自然保护地生态系统服务功能这一问题框架,系统分析中国自然保护地在生态保护红线划定、旅游发展与文化要素表征3个方面存在的问题与障碍因素,通过政策梳理、学理辨析、国内外对比等研究方法提出以上三方面问题的破题策略。本文认为要建设与国际接轨、具有中国特色的自然保护地体系,需要运用“可接受的改变极限”思想开展红线划定与管控,因地制策、因时制宜、持续监测;需要加大游憩机会谱的研究及应用实践,实现生态保护与旅游发展相得益彰;需要重视自然保护地内文化景观的提炼识别及其表征、传播,重视国家公园文化认同意义表达。