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Sequestering Carbon Dioxide by the Use of the Energy Crop Miscanthus: Quantifying the Energy Production and Sequestration Potential of Europe Astley F. Hastings; Astley F. Hastings The University of Aberdeen Search for other works by this author on: This Site Google Scholar John Clifton-Brown; John Clifton-Brown IGER Search for other works by this author on: This Site Google Scholar Martin Wattenbach; Martin Wattenbach University of Aberdeen Search for other works by this author on: This Site Google Scholar Paul Mitchell; Paul Mitchell University of Aberdeen Search for other works by this author on: This Site Google Scholar Pete Smith Pete Smith University of Aberdeen Search for other works by this author on: This Site Google Scholar Paper presented at the EUROPEC/EAGE Conference and Exhibition, London, U.K., June 2007. Paper Number: SPE-107495-MS https://doi.org/10.2118/107495-MS Published: June 11 2007 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Hastings, Astley F., Clifton-Brown, John, Wattenbach, Martin, Mitchell, Paul, and Pete Smith. "Sequestering Carbon Dioxide by the Use of the Energy Crop Miscanthus: Quantifying the Energy Production and Sequestration Potential of Europe." Paper presented at the EUROPEC/EAGE Conference and Exhibition, London, U.K., June 2007. doi: https://doi.org/10.2118/107495-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE Europec featured at EAGE Conference and Exhibition Search Advanced Search AbstractGlobal warming caused by anthropological emissions of greenhouse gas (GHG) is now an inconvenient reality. CO2, the largest contributor, was emitted at the rate of 6 Gt C y-1 by burning fossil fuels in 1990, which are projected to rise to around 10 Gt C y-1 by 2020. Using bio-fuels, such as bio-ethanol or bio-diesel in transportation, or biomass in power generation reduces CO2 emissions as the carbon is fixed by the plants from the atmosphere and saves the equivalent fossil fuel.The biospheric flux of carbon from the soil and terrestrial biota to the atmosphere is about 120 Gt C y-1 and is roughly balanced by the fixation of carbon by photosynthesis. However, anthropological land use change, through increased agriculture and forestry, resulted in atmospheric emissions of 1.1 Gt C in 1990, projected to rise to 1.5 Gt C in 2020, so the production of biofuels is not GHG emission free if land use change is involved.This paper explores the GHG emission cost of the production of bio-fuels derived from energy crops and compares them to fossil fuels used in transport and electricity generation. The bio-fuels emission cost are presented for several land use scenarios showing that highest sequestration can be achieved by using existing arable land for bio-fuel production and not land with a currently undisturbed ecosystem.Considering these drivers and the GHG emissions, we model the future potential of Europe to produce bio-fuels with four different future land use and climate change scenarios and conclude that up to 20% of Europe's current primary energy consumption could be provided by bio-fuels by the year 2080 with a corresponding reduction in carbon emissions, taking into account the GHG cost of production.IntroductionThe global pattern of energy use is changing with the successive industrialization of the economies of South East Asia and Brazil, and more recently with the increasing pace of the industrialization of China and India. This has driven an increase in the demand for energy, and hence for fossil fuel, at the rate of 2–3% per year 1. The rate at which conventional oil production can be increased has been reduced by the lack of refining capacity, and the fact that nearly 50% of the world's proven and probable conventional light crude oil reserves have already been consumed 2. This flat-topping in the availability of oil has been compensated for by the increased availability of natural gas and new reserves of cheap coal. Natural gas has been increasing its share of the energy supply mix as the infrastructure and technology of its transportation is put into place both by pipelines, liquefaction and conversion to methanol. In developed economies, gas has displaced both oil and coal, whilst coal use has increased in developing economies, particularly in China. At the same time the use of nuclear energy has stagnated due to public concerns about waste storage and disposal.Globally, biomass currently provides around 46 EJ of bio-energy in the form of combustible biomass and wastes, liquid bio-fuels, renewable municipal solid waste, solid biomass/charcoal, and gaseous fuels. This share is estimated to be 13.4% of global primary energy supply 3 but this is mainly from "traditional biomass" estimated to provide 32EJ in 2002 of non-commercial firewood, charcoal and dung used for cooking and heating in developing countries 4. Such low-grade biomass provides around 35% of primary energy in many developing countries, but more than 70% in Africa 5. Keywords: climate change, grid block, Time Slice, Europe, coal, biomass, meteorological data, Upstream Oil & Gas, experiment, degree grid Subjects: Environment, Climate change This content is only available via PDF. 2007. 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Changes in the distribution of soil organic carbon (SOC) fractions - particulate organic carbon (POC; unprotected carbon) vs. mineral-associated organic carbon (MAOC; protected carbon) - affect SOC storage and stability. Here, we compile a SOC fraction dataset from 7219 soil samples across six continents. From 2000 to 2022, POC increases by 21.8% while MAOC decreases by 5.3%, leading to a net gain of 11.0% in SOC storage and a 29.1% increase in the POC/MAOC ratio. However, relative to undisturbed natural ecosystems, SOC declines in planted forests, grazed grasslands, and croplands with management practices such as heavy grazing and conventional tillage, primarily due to rapid declines in POC. Our results highlight that the global increase in SOC is mainly driven by POC, but warn of decreasing SOC stability associated with climate change and human activities. Thus, maintaining soil carbon sinks requires targeted strategies focusing on POC.

Abstract Agriculture in developing countries has attracted increasing attention in international negotiations within the United Nations Framework Convention on Climate Change for both adaptation to climate change and greenhouse gas mitigation. However, there is limited understanding about potential complementarity between management practices that promote adaptation and mitigation, and limited basis to account for greenhouse gas emission reductions in this sector. The good news is that the global research community could provide the support needed to address these issues through further research linking adaptation and mitigation. In addition, a small shift in strategy by the Intergovernmental Panel on Climate Change ( IPCC ) and ongoing assistance from agricultural organizations could produce a framework to move the research and development from concept to reality. In turn, significant progress is possible in the near term providing the basis for UNFCCC negotiations to move beyond discussion to action for the agricultural sector in developing countries.

Soil organic carbon sequestration (SOCseq) is considered the most attractive carbon capture technology to partially mitigate climate change. However, there is conflicting evidence regarding the potential of SOCseq. The additional storage potential on existing global cropland is missing. SOCseq is region-specific and conditioned by management but most global estimates use fixed accumulation rates or time frames. Here, we show how the SOC storage potential and its steady state varies globally depending on climate, land use and soil. Using 83,416 soil observations, we developed a quantile regression neural network that quantifies the SOC variation within soils with similar characteristics. This allows us to identify similar areas that present higher SOC with the difference representing an additional storage potential. The estimated additional SOC storage potential of 29 to 67 Pg C in the topsoil of global croplands equates to only 2 to 5 years of emissions offsetting and 32 % of agriculture's 92 Pg historical carbon debt estimate due to conversion from natural ecosystems. Since SOC is temperature-dependent, this potential is likely to reduce by 18 % by 2040 due to climate change.

Improving the amount of organic carbon in soils is an attractive alternative to partially mitigate climate change. However, the amount of carbon that can be potentially added to the soil is still being debated, and there is a lack of information on additional storage potential on global cropland. Soil organic carbon (SOC) sequestration potential is region-specific and conditioned by climate and management but most global estimates use fixed accumulation rates or time frames. In this study, we model SOC storage potential as a function of climate, land cover and soil. We used 83,416 SOC observations from global databases and developed a quantile regression neural network to quantify the SOC variation within soils with similar environmental characteristics. This allows us to identify similar areas that present higher SOC with the difference representing an additional storage potential. We estimated that the topsoils (0–30 cm) of global croplands (1,410 million hectares) hold 83 Pg C. The additional SOC storage potential in the topsoil of global croplands ranges from 29 to 65 Pg C. These values only equate to three to seven years of global emissions, potentially offsetting 35% of agriculture’s 85 Pg historical carbon debt estimate due to conversion from natural ecosystems. As SOC store is temperature-dependent, this potential is likely to reduce by 14% by 2040 due to climate change in a “business as usual” scenario. The results of this article can provide a guide to areas of focus for SOC sequestration, and highlight the environmental cost of agriculture.

Abstract The potential for climate change mitigation by bioenergy crops and terrestrial carbon sinks has been the object of intensive research in the past decade. There has been much debate about whether energy crops used to offset fossil fuel use, or carbon sequestration in forests, would provide the best climate mitigation benefit. Most current food cropland is unlikely to be used for bioenergy, but in many regions of the world, a proportion of cropland is being abandoned, particularly marginal croplands, and some of this land is now being used for bioenergy. In this study, we assess the consequences of land‐use change on cropland. We first identify areas where cropland is so productive that it may never be converted and assess the potential of the remaining cropland to mitigate climate change by identifying which alternative land use provides the best climate benefit: C 4 grass bioenergy crops, coppiced woody energy crops or allowing forest regrowth to create a carbon sink. We do not present this as a scenario of land‐use change – we simply assess the best option in any given global location should a land‐use change occur. To do this, we use global biomass potential studies based on food crop productivity, forest inventory data and dynamic global vegetation models to provide, for the first time, a global comparison of the climate change implications of either deploying bioenergy crops or allowing forest regeneration on current crop land, over a period of 20 years starting in the nominal year of 2000 ad . Globally, the extent of cropland on which conversion to energy crops or forest would result in a net carbon loss, and therefore likely always to remain as cropland, was estimated to be about 420.1 Mha, or 35.6% of the total cropland in Africa, 40.3% in Asia and Russia Federation, 30.8% in Europe‐25, 48.4% in North America, 13.7% in South America and 58.5% in Oceania. Fast growing C 4 grasses such as Miscanthus and switch‐grass cultivars are the bioenergy feedstock with the highest climate mitigation potential. Fast growing C 4 grasses such as Miscanthus and switch‐grass cultivars provide the best climate mitigation option on ≈485 Mha of cropland worldwide with ~42% of this land characterized by a terrain slope equal or above 20%. If that land‐use change did occur, it would displace ≈58.1 Pg fossil fuel C equivalent (C eq oil). Woody energy crops such as poplar, willow and Eucalyptus species would be the best option on only 2.4% (≈26.3 Mha) of current cropland, and if this land‐use change occurred, it would displace ≈0.9 Pg C eq oil. Allowing cropland to revert to forest would be the best climate mitigation option on ≈17% of current cropland (≈184.5 Mha), and if this land‐use change occurred, it would sequester ≈5.8 Pg C in biomass in the 20‐year‐old forest and ≈2.7 Pg C in soil. This study is spatially explicit, so also serves to identify the regional differences in the efficacy of different climate mitigation options, informing policymakers developing regionally or nationally appropriate mitigation actions.

Rice cultivation is a significant source of anthropogenic greenhouse gas (GHG) emissions, accounting for approximately 24% of global agricultural emissions. Methane emissions are particularly high in rice fields compared to other crops due to the anaerobic conditions created by continuous flooding. The adoption of alternate wetting and drying (AWD) is an approach to reduce these emissions significantly. However, AWD can also increase nitrous oxide emissions during drying phases. Therefore, farmers and their decisions play a central role in mitigating emissions from rice cultivation. In this study, we analyse the factors influencing the farmers’ behaviour by using the COM-B model to identify the key drivers and barriers affecting farmers' adoption of AWD practices. The COM-B model explains human behaviour (B) as the result of physical and psychological capability (C), physical and social opportunity (O), and reflective and automatic motivation (M). Data were collected through face-to-face surveys with 150 rice farmers in central region of Thailand between July and October 2024. Overall, farmers have positive attitudes toward AWD, with strong motivation to adopt this practice. This is seen in their agreement with statements about AWD's potential to reduce costs (96.7%) and save water (98%). Furthermore, farmers consider their current irrigation systems (96%) and terrain (87.3%) as feasible for implementing AWD on their fields. These findings align with the motivation and feasibility factors identified through factor analysis. Regarding barriers to adopting AWD, most farmers believe they know how to implement AWD, and these practices do not require significant investment, equipment, or additional workforce. However, operational factors highlighted challenges such as water availability (50%) and water monitoring difficulties (42.67%), which significant barriers to implementation. These findings indicate that farmers recognize their capability to adopt AWD practices, and the adoption does not significantly affect yield. Nevertheless, barriers such as limited water availability and insufficient social support hinder adoption.