Marginal abatement costs of greenhouse gas emissions: broadacre farming in the Great Southern Region of Western Australia

Broadacre agriculture is a major emitter of greenhouse gases (GHG). To improve efficiency of climate change policies, we need to know the marginal abatement costs of agricultural GHG. This article combines calculations of on‐farm GHG emissions with an input‐based distance function approach to estimate the marginal abatement costs for a broadacre farming system in the Great Southern Region of Western Australia. The results show that, in the study region, the average marginal abatement cost for the 1998–2005 periods was $29.3 per tonne CO₂‐e. Farms with higher crop output shares were found to have higher marginal abatement costs. Overall, our results indicate that broadacre agriculture is among the lowest cost sources of GHG mitigation.     

Information about Climate Change Mitigation: What Do Farmers Think?

The adoption of new practices by farmers is one of the key strategies to lower greenhouse gas (GHG) emissions from food production. In this context, effective knowledge transfer systems are essential to inform farmers about climate change, and to convince them of the benefits of new technologies. In this article, farmers’ opinions about climate change, their own efforts to mitigate climate change, and their suggestions on how to improve agricultural advice were assessed. To this end, a survey with over 500 livestock farmers was conducted in Ireland. The findings reveal a high awareness of the urgency to address climate change in general, but many farmers also think agricultural GHG emissions are an overstated problem. In addition, half of the surveyed farmers believe that implementing GHG mitigation measures will lower their profits. These findings underline the need to provide effective knowledge transfer to facilitate the uptake of GHG mitigation measures. When asking farmers directly, by way of text analysis, it emerges that simple messages, group and practical advice that is tailored to individual farming situations is important to farmers. As such, this article provides important insights that are of relevance for designing advisory campaigns to promote climate change mitigation.     

The Need for Comprehensive Climate Change Mitigation Policies in European Agriculture

During the last decade the European Union has shown a firm determination to move to a low carbon economy. Since 2008 the agricultural sector has been part of this strategy and is included in the EU effort sharing decision. Introducing specific GHG mitigation obligations for agriculture could be one option to achieve an overall GHG emission reduction target. One argument for this strategy would be that the agricultural sector is the main contributor of non‐CO₂ greenhouse gases. Nevertheless, a comprehensive EU mitigation policy would most likely have to take into account the particularities of its diverse agricultural sector, reflected by different trends in historical GHG emission reductions, and a varied mitigation cost structure between farming systems. Consequently, using targeted but flexible policy instruments may more equitably distribute the mitigation efforts across Member States and reduce cost inefficiencies. The increased uptake of technological and management emission mitigation measures would be crucial to keep mitigation costs for EU farmers at a minimum. However, while unilateral action would initially signal the EU's commitment to serious GHG mitigation effort in the sector, ultimately a multilateral agreement is needed to minimise emission leakage and to reduce global GHG emissions effectively.     

Addressing Uncertainty in Efficient Mitigation of Agricultural Greenhouse Gas Emissions

The agricultural sector, as an important source of greenhouse gas (GHG) emissions, is under pressure to reduce its contribution to climate change. Decisions on financing and regulating agricultural GHG mitigation are often informed by cost‐effectiveness analysis of the potential GHG reduction in the sector. A commonly used tool for such analysis is the bottom‐up marginal abatement cost curve (MACC) which assesses mitigation options and calculates their cumulative cost‐effective mitigation potential. MACCs are largely deterministic, typically not reflecting uncertainties in underlying input variables. We analyse the uncertainty of GHG mitigation estimates in a bottom‐up MACC for agriculture, for those uncertainties capable of quantitative assessment. Our analysis identifies the sources and types of uncertainties in the cost‐effectiveness analysis and estimates the statistical uncertainty of the results by propagating uncertainty through the MACC via Monte Carlo analysis. For the case of Scottish agriculture, the uncertainty of the cost‐effective abatement potential from agricultural land, as expressed by the coefficient of variation, was between 9.6% and 107.3% across scenarios. This means that the probability of the actual abatement being less than half of the estimated abatement ranged from <1% (in the scenario with lowest uncertainty) to 32% (in the scenario with highest uncertainty). The main contributors to uncertainty are the adoption rate and abatement rate. While most mitigation options appear to be ‘win–win’ under some scenarios, many have a high probability of switching between being cost‐ineffective and cost‐effective.     

Reducing greenhouse gas emissions from agriculture: Avoiding trivial solutions to a global problem

Three steps are required to successfully and efficiently reduce greenhouse gas (GHG) emissions from agriculture: (i) identification of the most GHG polluting farms, (ii) determining appropriate mitigation options for these farms, and (iii) selection between these options on the basis of their cost effectiveness. Carbon footprints of a sample of farms together with an analysis of the Kyoto Protocol show the difficulties encountered at each step. These difficulties are caused by: (i) failure to agree which functional unit to use to measure GHG emissions and pollution swapping; (ii) weaknesses in the Kyoto Protocol's territorial/production based accounting methodology, and (iii) lack of cost-effectiveness data. One consequence is that farmers may adopt mitigation activities that reduce their farm's, the UK agriculture sector's and the UK's emissions whilst inadvertently increasing global emissions: a trivial solution because it fails to address GHG emissions as a global problem. These difficulties, together with estimated agriculture sector marginal abatement cost curves that suggests emission reduction from all cost effective mitigation activities will not deliver targeted GHG emission reductions, means policy focus must be on demand rather than supply-side measures: the benefits and disadvantages of cap and trade mechanisms and carbon taxes are briefly discussed within an agricultural context.     

Achieving successful farmer engagement on greenhouse gas emission mitigation

This paper explores the potential for farmers’ engagement on the issues related to greenhouse gas (GHG) emission mitigation in extensive low-input livestock farming systems. The framework used was based on Participatory Action Research. This involved integrating quantitative evidence on GHG emission impacts at the farm level and qualitative data on the obstacles to the adoption of innovation based on farmers’ perceptions and attitudes to climate change. The study aims at building social capital among 14 farmers in the South West and West Midlands regions in England, and it evaluates the potential for the adoption of emission mitigation strategies. The Rapid Farm Practices Appraisal (RFPA) tool was created to assess farm practices based on their mitigation potential. Practices were assessed twice over 6–9 months. Semi-structured interviews were used to assess barriers and opportunities to farmer engagement and on-farm innovation. Farmers were invited to a focus group meeting to network with other farmers and engage with researchers. All farmers participated in the 2 farm assessments, but only half the farmers adopted changes in farm management. All farmers appreciated the RFPA tool, the clearness of the information provided and the focus of the tool on practices directly. The main obstacles to innovation were limited financial capital, lack of trust in government action and confusion over the effectiveness of farm advice on mitigation. The lack of long-term flexibility of agricultural policies and the source of information greatly influenced the acceptance of advice. Results suggest the potential for the expansion of the RFPA tool to include economic assessment of farm practices and the engagement of a larger pool of farmers and farming systems. The tool could be used to support the GHG Action Plan and future environmental policies, and as an integrated self-assessment tool for farmers under Environmental Stewardship Schemes.     

Does carbon farming provide a cost‐effective option to mitigate GHG emissions? Evidence from China

In this study, we apply a whole farm bioeconomic analysis to explore the changes in land use, farm practices and on‐farm greenhouse gas (GHG) emission under varying levels of agricultural greenhouse gas abatement incentives in the form of a carbon tax for a semi‐arid crop‐livestock farming system in China's Loess Plateau. Our results show that the optimised agricultural enterprises move towards being cropping‐dominated reducing on‐farm emission since livestock perform is the major source of emission. Farmers employ less oats‐based and rapeseed‐based rotations but more dry pea‐based rotations in the optimal enterprise mix. A substantial reduction in on‐farm greenhouse gas emission can be achieved at low cost with a small increase in carbon incentives. Our estimates indicate that crop‐livestock farmers in China's Loess Plateau may reduce their on‐farm GHG emission between 16.6 and 33 per cent with marginal abatement costs <￥100/t CO₂e and ￥150/t CO₂e in 2015 Chinese Yuan. The analysis implies that reducing greenhouse gas emission in China's semi‐arid crop‐livestock agriculture is potentially a low‐cost option.     

Setting Climate Action as the Priority for the Common Agricultural Policy: A Simulation Experiment

We quantitatively assess the impacts of re-allocating budgetary resources within Pillar 1 of the EU's Common Agricultural Policy (CAP) from direct income support to a direct greenhouse gas (GHG) reduction subsidy for EU farmers. The analysis is motivated by the discussion on the future CAP, with calls for both an increased ambition on climate action from the agricultural sector and for a more incentive-based delivery system of direct payments under strict budgetary restrictions. By conducting a simulation experiment with an agricultural partial equilibrium model (CAPRI), we are able to factor in farmers’ supply and technology-adjusting responses to the policy change and to estimate the potential uptake of the GHG-reduction subsidy in EU regions. We find that a budget-neutral re-allocation of financial resources towards subsidised emission savings can reduce EU agricultural non-CO₂ emissions by 21% by 2030, compared to a business-as-usual baseline. Two-thirds of the emission savings are due to changes in production levels and composition, implying that a significant part of the achieved GHG reduction is offset globally by emission leakage. At the aggregated level, the emission-saving subsidy and increased producer prices compensate farmers for the foregone direct income support, but differences in regional impacts indicate accelerated structural change and heterogeneous income effects in the farm population. We conclude that the assumed regional budget-neutrality condition introduces inefficiencies in the incentive system, and the full potential of the EU farming sector for GHG emissions reduction is not reached, leaving ample room for the design of more efficient agricultural policies for climate action.     

Bilateral Information Asymmetry in the Design of an Agri‐Environmental Policy: An Application to Peatland Retirement in Norway

Agriculture is a significant source of global greenhouse gas (GHG) emissions. GHG mitigation through agri‐environmental programmes could be important in achieving emission reduction targets under the 2015 UN climate agreement. This study uses the principal‐agent model to examine a peatland retirement programme to reduce agricultural emissions in Norway. The focus is on the role of the government's private information in programme design. Two cases are examined. First, optimal contracts are derived when farmers have private information about the costs of implementing peat land retirement, but the government reveals its information on the resulting public benefits through differentiated contracts. This corresponds to the standard targeting strategy with one‐sided information asymmetry. In the second case, an informed principal model developed by Maskin and Tirole in a 1990 study is employed to address bilateral information asymmetry. Using the informed principal model, the government offers the same menu of contracts to farmers in order not to disclose information on the public benefits from land retirement. Empirical results show that the government can achieve a higher payoff by using a pooling offer.     

Climate change reduces the mitigation obtainable from sequestration in an Australian farming system

Agricultural research on climate change generally follows two themes: (i) impact and adaptation or (ii) mitigation and emissions. Despite both being simultaneously relevant to future agricultural systems, the two are usually studied separately. By contrast, this study jointly compares the potential impacts of climate change and the effects of mitigation policy on farming systems in the central region of Western Australia’s grainbelt, using the results of several biophysical models integrated into a whole‐farm bioeconomic model. In particular, we focus on the potential for interactions between climate impacts and mitigation activities. Results suggest that, in the study area, farm profitability is much more sensitive to changes in climate than to a mitigation policy involving a carbon price on agricultural emissions. Climate change reduces the profitability of agricultural production and, as a result, reduces the opportunity cost of reforesting land for carbon sequestration. Nonetheless, the financial attractiveness of reforestation does not necessarily improve because climate change also reduces tree growth and, therefore, the income from sequestration. Consequently, at least for the study area, climate change has the potential to reduce the amount of abatement obtainable from sequestration – a result potentially relevant to the debate about the desirability of sequestration as a mitigation option.     

Where in the world is it cheapest to cut carbon emissions?*

Countries with low marginal costs of abating carbon emissions may have high total costs, and vice versa, for a given climate mitigation policy. This may help to explain different countries’ policy stances on climate mitigation. We hypothesize that, under a common percentage cut in emissions intensity relative to business as usual (BAU), countries with higher BAU emission intensities have lower marginal abatement costs, but total costs relative to output will be similar across countries, and under a common carbon price, relative total costs are higher in emission‐intensive countries. Using the results of the 22nd Energy Modeling Forum (EMF‐22), we estimate marginal abatement cost curves for the US, EU, China and India, which we use to estimate marginal and total costs of abatement under a number of policy options currently under international debate. This analysis provides support for our hypotheses, although its reliability is limited by the shortcomings of the EMF‐22 models and the degree to which our econometric model can adequately account for the substantial differences among them.     

农业社会化服务对农户福利的影响研究——基于农药减量增效服务的实证检验

目的 厘清农业社会化服务对农户家庭收入的影响机制,对提升农户福利水平和完善农业社会化服务体系具有重要意义。方法 文章运用内生转换模型、中介效应模型等方法,重点关注于农药减量增效、保障农产品质量安全的农业社会化服务,实证检验其对农户福利的影响。结果 （1）样本农户中农业社会化服务平均采纳项数仅为2.24项,其中统防统治服务和质量检测服务的采用率均不足20%;（2）农业社会化服务能够通过改变农户传统施药观念与提升种植管理水平,改善农户福利,表现为在反事实假设下,实际采用农业社会化服务的农户若不采用,其家庭人均年收入将下降3.78%;（3）农业社会化服务福利效应存在群组差异性,对于高文化程度、低农业劳动比、种植规模较小的农户而言,采用农业社会化服务后福利水平改善程度相对较大。结论 应持续加强对农业社会化服务的组织形式与服务方式的创新,分类引导不同类型农户理性采用农业社会化服务,充分发挥出农业社会化服务的福利效应。     

农户农业碳排放效率差异及多层次影响因素——以陕西省米脂县为例

目的 分析农户尺度农业碳排放效率差异并揭示多层次影响因素,对提供微观决策支持和推进农业农村低碳高效发展意义重大。方法 文章以陕西省米脂县为例,在测算57个村庄共861个农户农业碳排放及效率的基础上,从农户尺度分析农业碳排放及效率差异,最后基于多层次模型揭示其影响因素。结果 （1）农户整体农业碳排放效率较低,且示范村中的农户农业碳排放效率高于非示范村农户,示范村与非示范村下同一类型农户的冗余类型及占比和示范村（或非示范村）不同类型农户的冗余类型及占比差异明显;（2） 年龄、务农年限、教育水平和农业技能培训是影响农户农业碳排放量的主要因素。（3）就全体农户而言,乡村振兴示范村、距县城距离和政府支持力度是影响农户农业碳排放效率的主要环境变量,务农年限和受教育水平是影响农户农业碳排放效率的主要个体变量。影响示范村与非示范村农户农业碳排放效率的因素有较大差异。结论 不同类型农户农业碳排放效率和影响因素迥异,应根据村庄环境、农户特征等进行差异化政策支持。     

What Drives Marginal Abatement Costs of Greenhouse Gases on Dairy Farms? A Meta‐modelling Approach

This paper examines the relationships between the marginal abatement costs (MAC) of greenhouse gas (GHG) emissions on dairy farms and factors such as herd size, milk yield and available farm labour, on the one hand, and prices, GHG indicators and GHG reduction levels, on the other. A two‐stage Heckman procedure is used to estimate these relationships from a systematically designed set of simulations with a highly detailed mixed integer bio‐economic farm‐level model. The resulting meta‐models are then used to analyse how MAC vary across farm‐level conditions and GHG measures. We find that simpler GHG indicators lead to significantly higher MAC, and that MAC strongly increase beyond a 1–5% emission reduction, depending on farm attributes and the chosen indicator. MAC decrease rapidly with increasing farm size, but the effect levels off beyond a herd size of 40 cows. As expected, the main factors driving gross margins per dairy cow also significantly influence mitigation costs. Our results indicate high variability of MAC on real life farms. In contrast to time consuming simulations with the complex mixed integer bio‐economic programming model, the meta‐models allow the distribution of MAC in a farm population to be efficiently derived and thus could be used to upscale to regional or sector level.     

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.     

Understanding the adoption of climate change adaptation strategies among smallholder farmers: Evidence from land reform beneficiaries in South Africa

Climatic change has a negative impact on people’s livelihoods, agriculture, freshwater supply and other natural resources that are important for human survival. Therefore, understanding how rural smallholder farmers perceive climate change, climate variability, and factors that influence their choices would facilitate a better understanding of how these farmers adapt to the negative impacts of climate change. A Zero-inflated double hurdle model was employed to estimate the factors influencing farmers’ adoption of adaptation strategies and intensity of adoption at the household level in South Africa. Different socioeconomic factors such as gender, age, and experience in crop farming, institutional factors like access to extension services, and access to climate change information significantly influenced the adoption of climate change adaptation strategies among beneficiaries of land reform in South Africa. Concerning intensity of adoption, age, educational level, farming experience, on-farm training, off-farm income, access to information through ICT and locational variables are the significant determinants of intensity of adaptation strategies. Thus, education attainment, non-farm employment, farming experience are significant incentives to enhance smallholder farmers' adaptive capacity through the adoption of many adaptation approaches. This study therefore concluded that farm-level policy efforts that aim to improve rural development should focus on farmers’ education, on-farm demonstration and non-farm employment opportunities that seek to engage the farmers, particularly during the off-cropping season. The income from non-farm employment can be plough-back into farm operations such as the adoption of soil and water conservation, use of improved planting varieties, insurance, among others to mitigate climate variability and subsequently increase productivity. Policies and investment strategies of the government should be geared towards supporting education, providing on-farm demonstration trainings, and disseminating information about climate change adaptation strategies, particularly for smallholder farmers in the country. Thus, the government, stakeholders, and donor agencies must provide capacity-building innovations around the agricultural extension system and education on climate change using information and communication technologies.     

Livestock intensification as a climate policy: Lessons from the Brazilian case

Brazil is trying to identify ways to ally economic growth with climate change mitigation. Productivity gains in livestock have been pointed out as a promising alternative to achieve that goal. Thus, this paper analyses the economic impacts of a policy of productivity gains in the Brazilian livestock. Besides, we evaluate if the policy may conciliate agricultural growth and deforestation control, bearing in mind the reduction of greenhouse gas (GHG) emissions from land-use changes. The analysis was carried out through a computable general equilibrium (CGE) model, tailored to represent land-use changes, GHG emissions and removals. Besides, it made progress modeling the heterogeneity of climate, soils, and emissions in inter-regional models with many regions. The results show that productivity gains can effectively “save” land and thus avoid deforestation, especially in the Amazon and Cerrado (savannah) biomes. The policy also may boost the economic growth, spreading it to other regions of Brazil, like Centre-West and North, and increasing income and consumption in those places. However, as a climate policy, focused on the reduction of GHG emissions, the results may be counterproductive. The net amount issued may increase, as a result of the positive stimulus of the policy on the economy, and GHG emissions are directly related to the economic growth.     

Marginal Abatement Cost Curves for UK Agricultural Greenhouse Gas Emissions

This article addresses the challenge of developing a ‘bottom‐up’ marginal abatement cost curve (MACC) for greenhouse gas (GHG) emissions from UK agriculture. An MACC illustrates the costs of specific crop, soil and livestock abatement measures against a ‘business as usual’ scenario. The results indicate that in 2022 under a specific policy scenario, around 5.38 Mt CO₂ equivalent (e) could be abated at negative or zero cost. A further 17% of agricultural GHG emissions (7.85 Mt CO₂e) could be abated at a lower unit cost than the UK Government’s 2022 shadow price of carbon [£34 (tCO₂e)^?1]. The article discusses a range of methodological hurdles that complicate cost‐effectiveness appraisal of abatement in agriculture relative to other sectors.     

An accelerating treadmill and an overlooked contradiction in industrial agriculture: Climate change and nitrogen fertilizer

In this article, we explore if and why farmers are responding to the impacts of climate change with practices that increase greenhouse gas emissions. Our examination focuses on heavy rainfall events and Midwestern corn farmers' nitrogen fertilizer management. Due to climate change, the frequency and intensity of heavy rain events is increasing across the Midwest. These events increase nitrogen loss to the environment and introduces economic risks to farmers. Drawing from a theoretical framework that merges O'Connor's second contradiction of capitalism and Schnaiberg's treadmill of production, we argue farmers' responses to these events reflect the second contradiction, increasing contributions to climate change, and are shaped by treadmill‐like political‐economic pressures. We examine this using a qualitative sample of 154 farmers across Indiana, Iowa, and Michigan. Given profit imperatives, adapting farmers in our sample primarily used increased nitrogen application rates to reduce their vulnerability to heavy rains. As nitrogen rate is directly associated with nitrous oxide emissions, this adaptive strategy is effective but increases agricultural contributions to climate change. This preliminarily suggests that the political‐economic structure encourages farmers to respond to climate change in ways that accelerate the environmental contradictions of industrial agriculture.     

村集体作为、农户感知与农户农业社会化服务采纳——基于空间距离和社会距离的调节效应

目的 小农户对于农业社会化服务的采纳行为是农户与现代农业有机衔接的核心体现,村集体兼具政府代理人与农户当家人的双重身份,其作为可有效缓解采纳不足问题,助推农业现代化的发展。方法 文章基于S-O-R（Stimuli-Organism-Response）即刺激-有机体-反应理论分析框架,选取陕西省关中地区69份村级样本和1 602份农户样本数据,利用结构方程模型（Structural Equation Modeling,SEM）和分层线性回归模型（Hierarchical Regression Model,HLM）分析村集体作为对农户农业社会化服务采纳的影响,验证农户感知的中介效应,并利用多群组分析探究社会化服务供需双方的空间距离和社会距离的调节效应。结果 村集体参与农业社会化服务工作对农户农业社会化服务采纳具有显著的正向影响,农户感知的信任度和行为态度维度在村集体作为对农户农业社会化服务采纳影响中具有重要的中介作用,群组分析结果表明,社会化服务供需双方的空间距离和社会距离在村集体作为对农户农业社会化服务采纳的影响中具有调节作用。结论 应注重农户反馈,以差异化战略提升农户适应性,通过村集体积极作为搭建起供需双方的合作桥梁,优化社会化服务工作,推动农业高质量发展。