Greenhouse Gas Mitigation Potential in Agricultural Soils

Greenhouse gas (GHG) mitigation options in the Russian forest sector include: afforestation and reforestation of unforested/degraded land area; enhanced forest productivity; incorporation of nondestructive methods of wood harvesting in the forest industry; establishment of land protective forest stands; increase in stand age of final harvest in the European part of Russia; increased fire control; increased disease and pest control; and preservation of old growth forests in the Russian Far-East, which are presently threatened. Considering the implementation of all of the options presented, the GHG mitigation potential within the forest and agroforestry sectors of Russia is approximately 0.6–0.7 Pg C/yr or one half of the industrial carbon emissions of the United States. The difference between the GHG mitigation potential and the actual level of GHGs mitigated in the Russian forest sector will depend to a great degree on external financing that may be available. One possibility for external financing is through joint implementation (JI). However, under the JI process, each project will be evaluated by considering a number of criteria including also the difference between the carbon emissions or sequestration for the baseline (or reference) and the project case, the permanence of the project, and leakage. Consequently, a project level assessment must appreciate the near-term constraints that will face practitioners who attempt to realize the GHG mitigation potential in the forest and agroforestry sectors of their countries.

Climate change mitigation strategies cannot be evaluated solely in terms of energy cost and greenhouse gas (GHG) mitigation potential. Maintaining GHGs at a "safe" level will require fundamental change in the way we approach energy production, and a number of environmental, economic, and societal factors will come into play. Water is an essential component of energy production, and water resource constraints will limit our options for meeting society's growing demand for energy while also reducing GHG emissions. This study evaluates these potential constraints from a global perspective by revisiting the climate wedges proposal of Pacala and Socolow (Science2004, 305 (5686), 968-972) and evaluating the potential water-use impacts of the wedges associated with energy production. GHG mitigation options that improve energy conversion or use efficiency can simultaneously reduce GHG emissions, lower energy costs, and reduce energy impacts on water resources. Other GHG mitigation options (e.g., carbon capture and sequestration, traditional nuclear, and biofuels from dedicated energy crops) increase water requirements for energy. Achieving energy sustainability requires deployment of alternatives that can reduce GHG emissions, water resource impacts, and energy costs.

Abstract. This study assesses greenhouse gas (GHG) mitigation options for the agriculture sector. The Long-range Energy Alternatives Planning (LEAP) model was used to develop a framework to assess future trends in energy demand and associated GHG emissions for the agriculture sector and to assess various GHG mitigation options associated with energy consumption. A business-as-usual (reference) scenario and 32 GHG mitigation scenarios were developed for the years 2009-2050 using the LEAP model. A case study for Alberta, Canada, was conducted. In the model, GHG mitigation scenarios were developed for the energy demand side (e.g., farm machines, farm transportation, lighting, and ventilation) based on efficiency improvements and the use of renewable energy. The mitigation scenarios were divided into two planning horizons based on technology penetration: slow penetration (2009-2050) and fast penetration (2009-2030). For each planning horizon, 16 scenarios were assessed. Of all farm machines, efficient diesel tractors have the highest GHG mitigation potential: 12.35 MT of CO2 equivalent by 2050 and 4.7 MT of CO2 equivalent by 2030. In addition, GHG abatement cost curves show that biodiesel tractors and efficient diesel tractors have the highest GHG mitigation potential, with attractive abatement costs of -$62 and -$11 tonne-1 of CO2 mitigated by 2050, respectively. Keywords: Abatement cost, Agriculture sector, Energy efficiency, GHG mitigation, LEAP model.

Mitigating the greenhouse gas emissions from urban roadway lighting in China via energy-efficient luminaire adoption and renewable energy utilization

Nitrogen nutrient supply and greenhouse gas mitigation potentials from cover crops across Chinese croplands

Agriculture is the source of 16 percent of Australia's greenhouse gas (GHG) emissions. Research has shown that changes in agricultural practices can increase carbon sequestration in soils and/or vegetation and reduce GHG emissions. Given worldwide commitments to reduce GHG emissions, there is a need to better understand the potential for Australian agriculture to contribute to GHG mitigation. GHG abatement practices will only be adopted if profitable to farmers. Without strong evidence for increased profitability, there is no incentive for farmers to move away from their current practices. Therefore, it is necessary to incorporate economics in any assessment of the potential for Australian farms to contribute to GHG mitigation. We performed an integrated modelling exercise to predict the GHG mitigation potential and whole-farm economic implications of different mitigation practices that can be implemented on Australian grain farms. This exercise was undertaken in two stages. In the first stage, a range of potential management practices that could provide GHG abatement were identified; these involved adding extra organic matter to the soil or altering nitrogen fertiliser use. The Agricultural Production Systems sIMulator (APSIM) was used to estimate the effects of abatement practices on productivity, soil carbon sequestration, nitrous oxide emissions and net GHG emissions over time. In the second stage, we develop an economic model that predicts annual revenues at a paddock scale, as well as whole-farm costs and benefits. Taking a whole-farm approach ensures that the full costs of different practices, such as investment in new capital equipment, is included. We present results for a 6,000 hectare dryland cropping farm in the north-central wheatbelt of Western Australia. This area is representative of the typical Mediterranean climate found in some of Australia's major grain growing regions. We predict that stubble retention and other organic matter additions increase soil carbon, which is important for greenhouse gas emissions reductions. Productivity gains are possible under some of the GHG abatement practices, i.e. GHG abatement and productivity gains can be achieved simultaneously. Increasing nitrogen fertiliser application or replacing volunteer, weedy pastures with improved, legume pastures are predicted to increase earnings and operating profits. However, when accounting for interest and tax, there was no economic advantage or disadvantage of adopting any of the GHG abatement practices. While gross margins per hectare are positive in almost every season, the whole-farm annual profits were negative for 30-40 percent of years. This study demonstrates the benefits of comprehensive economic analyses to accompany any biophysical analyses of the GHG mitigation potential of the Australian agricultural industry, and outlines a framework in which economic and biophysical analyses can be combined.

Spatially explicit database on crop-livestock management, soil, climate, greenhouse gas emissions and mitigation potential for all of Bangladesh

Anaerobic digestion to produce biogas is an important decentralised renewable energy technology. Production varies extensively between different countries and within countries, as biogas production is heavily dependent on local and regional feedstocks. In Germany, distinct regional differences can be observed. Therefore, understanding the kinds of biogas systems operating within a region is crucial to determine their greenhouse gas (GHG) mitigation potential and carbon neutrality. This is the first study to conduct an integrated life cycle assessment of biogas configurations in the landscape (biogas plants and their biomass catchments) for an entire region. RELCA a ‘REgional Life Cycle inventory Assessment’ approach was used to model the GHG mitigation potential of 425 biogas plants in the region of Central Germany (CG), aggregated to nine biogas clusters, based on feedstock mix (e.g. animal manures and energy crops) and installed capacity. GHG emission profiles were generated to compare and to identify the role of GHG credits and size of installed capacity on the mitigation performance of the regional biogas clusters. We found that smaller scaled slurry dominant clusters had significantly better GHG mitigation performance (−0.1 to −0.2 kg CO2eq kWhel−1), than larger energy crop dominant (ECdom) clusters (0.04–0.16 kg CO2eq kWhel−1), due to lower cultivation emissions and larger credits for avoided slurry storage. Thus, for the CG region larger ECdom clusters should be targeted first, to support GHG mitigation improvements to the overall future electricity supplied by the regional biogas systems. With the addition of GHG credits, the CG region is producing biogas with GHG savings (−0.15 kg CO2eq kWhel−1, interquartile range: 0.095 kg CO2eq kWhel−1). This infers that biogas production, as a waste management strategy for animal manures, could have important ramifications for future policy setting and national inventory accounting.

Chapter 23 - Economic Outcomes of Greenhouse Gas Mitigation Options

We assessed the economic suitability of 4 greenhouse gas (GHG) mitigation options and one GHG offset option for an improvement of the GHG balance of a representative Swiss suckler cow farm housing 35 Livestock units and cultivating 25 ha grassland. GHG emissions per kilogram meat in the economic optimum differ between the production systems and range from 18 to 21.9 kg CO2-eq./kg meat. Only GHG offset by agroforestry systems showed the potential to significantly reduce these emissions. Depending on the production system agroforestry systems could reduce net GHG emissions by 66% to 7.3 kg CO2-eq./kg meat in the most intensive system and by 100% in the most extensive system. In this calculation a carbon sequestration rate of 8 t CO2/ha/year was assumed. The potential of a combination of the addition of lipids to the diet, a cover of the slurry tank and the application of nitrification inhibitors only had the potential to reduce GHG emissions by 12% thereby marginal abatement costs are increasing much faster than for agroforestry systems. A reduction of the GHG emissions to 7.5 kg CO2-eq./kg meat—possible with agroforestry only—raised costs between 0.03 CHF/kg meat and 0.38 CHF/kg meat depending on the production system and the state of the system before the reduction. If GHG emissions were reduced maximally average costs ranged between 0.37 CHF/kg meat, if agroforestry had the potential to reduce net GHG emissions to 0 kg CO2-eq., to 1.17 CHF/kg meat if also other options had to be applied.

For many developing countries, the land use sector, particularly agriculture and forestry, represents a large proportion of their greenhouse gas (GHG) emissions, making this sector a priority for GHG mitigation activities. Previous global surveys (e.g., IPCC 2000) as well as the most recent IPCC assessment report clearly indicate that the greatest technical potential for carbon sequestration and reductions of non-CO2 GHG emissions from the land use sector is in developing countries. Estimates that consider economic feasibility suggest that agriculture and forestry together provide among the greatest opportunities for short-term and low-cost mitigation measures across all sectors of the global economy1 (IPCC 2007). In addition, it is widely recognized that the ecosystem changes entailed by most mitigation practices, i.e., building soil organic matter, reducing losses and tightening nutrient cycles, more efficient production systems and preserving native vegetation, are well aligned with goals of increasing food security and rural development as well as buffering land use systems against climate change (Lal 2004). Hence, there is growing interest in jump-starting the capacity for broad-based engagement in agriculturally-based GHG mitigation projects in developing countries.

Better information on greenhouse gas (GHG) emissions and mitigation potential in the agricultural sector is necessary to manage these emissions and identify responses that are consistent with the food security and economic development priorities of countries. Critical activity data (what crops or livestock are managed in what way) are poor or lacking for many agricultural systems, especially in developing countries. In addition, the currently available methods for quantifying emissions and mitigation are often too expensive or complex or not sufficiently user friendly for widespread use.The purpose of this focus issue is to capture the state of the art in quantifying greenhouse gases from agricultural systems, with the goal of better understanding our current capabilities and near-term potential for improvement, with particular attention to quantification issues relevant to smallholders in developing countries. This work is timely in light of international discussions and negotiations around how agriculture should be included in efforts to reduce and adapt to climate change impacts, and considering that significant climate financing to developing countries in post-2012 agreements may be linked to their increased ability to identify and report GHG emissions (Murphy et al 2010, CCAFS 2011, FAO 2011).

Climate Change and Health: Strengthening the Evidence Base for Policy

Pig manure currently results in sizeable greenhouse gas emissions, during storage and spreading to land. Anaerobic digestion and hydrothermal carbonisation could provide significant greenhouse gas mitigation, as well as generate renewable heat and power (with anaerobic digestion), or a peat-like soil amendment product (with hydrothermal carbonisation). The greenhouse gas mitigation potential associated with avoidance of pig manure storage and spreading in the UK, EU, and China, as well as the potential to provide heat and power by anaerobic digestion and soil amendment products by hydrothermal carbonisation was herein determined. In each case, the mono-conversion of pig manure is compared to co-conversion with a 50:50 mixture of pig manure with grass. Anaerobic digestion displayed a greater greenhouse gas mitigation potential than hydrothermal carbonisation in all cases, and co-processing with grass greatly enhances greenhouse gas mitigation potential. China has the largest greenhouse gas mitigation potential (129 MT CO2 eq), and greatest mitigation per kg of pig manure (1.8 kgCO2/kg pig manure volatile solids). The energy grid carbon intensity has a significant impact on the greenhouse gas mitigation potential of the different approaches in the different regions. Pig manure is generated in large amounts in China, and the energy generated from biogas offsets a higher carbon intensity grid. Greenhouse gas savings from the anaerobic digestion of pig manure and grass have been calculated to provide a significant potential for reducing total greenhouse gas emissions representation in China (1.05%), the EU (0.92%), and the UK (0.19%). Overall, the utilisation of pig manure could bring about substantial greenhouse savings, especially through co-digestion of pig manure with grass in countries with large pig farming industries and carbon intense energy mixes.

Climate-smart agriculture (CSA) is an approach that helps guide actions to transform agri-food systems towards green and climate-resilient practices and it remains prominent in food systems transformation in the light of increasing climate change impacts. Unfortunately, the quantification of the greenhouse gas (GHG) mitigation potential of CSA approaches is currently limited. Using the Cool Farm Tool (CFT), this paper quantifies the GHG mitigation of CSA based on farm-level experimental data. Individual interviews and focus group discussions were also conducted to identify farmers’ choices and willingness to adopt CSA practices. The study compared the GHG emission mitigation of CSA practices for two scenarios (baseline and mitigation). The study found that organic fertilizer input, residue incorporation, no-inorganic fertilizer and no-pesticide input reduced GHG emission intensity of sorghum (to 93.2 ± 25 kg CO2e GHG kg− 1 sorghum), rice (79.2 ± 22 kg CO2e GHG kg− 1 rice) and groundnut (69.7 ± 20 kg CO2e GHG kg− 1 groundnut) compared to the baseline. Lower GHG emission intensity was achieved with higher crop yield under CSA interventions. The study recommends that CSA promoters such as the Consultative Group for International Agriculture Research (CGIAR), Food and Agriculture Organization (FAO) and the World Bank focus on crop-specific CSA practices for higher GHG mitigation. CSA promoters such as the CGIAR, FAO and the World Bank should embrace participatory processes such as farmer schools to increase CSA uptake.