Ecosystem Good and Service Co-Effects of Terrestrial Carbon Sequestration: Implications for the U.S. Geological Survey’s LandCarbon Methodology

This paper describes specific ways in which the analysis of ecosystem goods and services can be included in terrestrial carbon sequestration assessments and planning. It specifically reviews the U.S. Geological Survey’s LandCarbon assessment methodology for ecosystem services. The report assumes that the biophysical analysis of co-effects should be designed to facilitate social evaluation. Accordingly, emphasis is placed on natural science strategies and outputs that complement subsequent economic and distributional analysis.ecosystem services, carbon sequestration, land use planning

ECONOMICS OF SEQUESTERING CARBON IN THE U.S. AGRICULTURAL SECTOR

Atmospheric concentrations of greenhouse gases can be reduced by withdrawing carbon from the atmosphere and sequestering it in soils and biomass. This report analyzes the performance of alternative incentive designs and payment levels if farmers were paid to adopt land uses and management practices that raise soil carbon levels. At payment levels below $10 per metric ton for permanently sequestered carbon, analysis suggests landowners would find it more cost effective to adopt changes in rotations and tillage practices. At higher payment levels, afforestation dominates sequestration activities, mostly through conversion of pastureland. Across payment levels, the economic potential to sequester carbon is much lower than the technical potential reported in soil science studies. The most cost-effective payment design adjusts payment levels to account both for the length of time farmers are willing to commit to sequestration activities and for net sequestration. A 50-percent cost-share for cropland conversion to forestry or grasslands would increase sequestration at low carbon payment levels but not at high payment levels.Carbon sequestration, greenhouse gas mitigation, afforestation, conservation tillage, no-till, incentive design, leakage, carbon stock, permanence, Environmental Economics and Policy,

Great SCO2T! Rapid tool for carbon sequestration science, engineering, and economics

CO2 capture and storage (CCS) technology is likely to be widely deployed in coming decades in response to major climate and economics drivers: CCS is part of every clean energy pathway that limits global warming to 2C or less and receives significant CO2 tax credits in the United States. These drivers are likely to stimulate capture, transport, and storage of hundreds of millions or billions of tonnes of CO2 annually. A key part of the CCS puzzle will be identifying and characterizing suitable storage sites for vast amounts of CO2. We introduce a new software tool called SCO2T (Sequestration of CO2 Tool, pronounced "Scott") to rapidly characterizing saline storage reservoirs. The tool is designed to rapidly screen hundreds of thousands of reservoirs, perform sensitivity and uncertainty analyses, and link sequestration engineering (injection rates, reservoir capacities, plume dimensions) to sequestration economics (costs constructed from around 70 separate economic inputs). We describe the novel science developments supporting SCO2T including a new approach to estimating CO2 injection rates and CO2 plume dimensions as well as key advances linking sequestration engineering with economics. Next, we perform a sensitivity and uncertainty analysis of geology combinations (including formation depth, thickness, permeability, porosity, and temperature) to understand the impact on carbon sequestration. Through the sensitivity analysis we show that increasing depth and permeability both can lead to increased CO2 injection rates, increased storage potential, and reduced costs, while increasing porosity reduces costs without impacting the injection rate (CO2 is injected at a constant pressure in all cases) by increasing the reservoir capacity.Comment: CO2 capture and storage; carbon sequestration; reduced-order modeling; climate change; economic

Ozone effects on net primary production and carbon sequestration in the conterminous United States using a biogeochemistry model

Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change Website. (http://mit.edu/globalchange/www/)Includes bibliographical references (p. 20-21)The effects of air pollution on vegetation may provide an important control on the carbon cycle that has not yet been widely considered. Prolonged exposure to high levels of ozone, in particular, has been observed to inhibit photosynthesis by direct cellu lar damage within the leaves and through changes in stomatal conductance. We have incorporated empirical equations derived for trees (hardwoods and pines) and crops into the Terrestrial Ecosystem Model version 4.3 (TEM 4.3) to explore the effects of ozon e on net primary production and carbon sequestration across the conterminous United States. Our results show up to a 5% reduction in Net Primary Production (NPP) in response to modeled historical ozone levels during the late 1980s to early 1990s. The lar ge st decreases (over 20% in some locations) occur in the eastern U.S. and Midwest, during months with high ozone levels and high productivity. Carbon sequestration during the 1980s is reduced by 30 to 70 Tg C/yr with the presence of ozone, or 5 to 23% o f recent estimates of the total carbon sequestration for the U.S. Thus the effects of ozone on NPP and carbon sequestration should be factored into future calculations of the U.S. carbon budget

Appreciating interconnectivity between habitats is key to Blue Carbon management

We welcome the recent synthesis by Howard et al. (2017), which drew attention to the role of marine systems and natural carbon sequestration in the oceans as a fundamental aspect of climate-change mitigation. The importance of long-term carbon storage in marine habitats (ie “blue carbon”) is rapidly gaining recognition and is increasingly a focus of national and international attempts to mitigate rising atmospheric emissions of carbon dioxide. However, effectively managing blue carbon requires an appreciation of the inherent connectivity between marine populations and habitats. More so than their terrestrial counterparts, marine ecosystems are “open”, with high rates of transfer of energy, matter, genetic material, and species across regional seascapes (Kinlan and Gaines 2003). We suggest that policy frameworks, and the science underpinning them, should focus not only on carbon sink habitats but also on carbon source habitats, which play critical roles in marine carbon cycling and natural carbon sequestration in the oceans

No-till agriculture – a climate smart solution?

No-tillage farming systems or no-till, as an aspect of conservation farming, are actively promoted by international research and development organizations to conserve soils and by this, ensure food security, biodiversity and water conservation. Instead of tilling before seeding, seeds are deposited directly into untilled soil by opening a narrow slot trench or band. Today, it is also seen as mitigation and adaptation option and thus being promoted as a measure to be supported under the United Nations Framework Convention on Climate Change (UNFCCC). There are even many voices advocating no-till to benefit from any future and existing carbon market. But: Is no-till the solution to reduce the hunger in the world and to mitigate climate change? It has been proven that no-till can signifi cantly reduce soil erosion and conserve water in the soils. This is regarded as a basis for higher and more stable crop yields – but science shows that this is not necessarily true. Discouragingly, there are numbers of examples of no yield benefits or even yield reductions under no-till in developing countries, especially in the first up to ten years. However, particularly the crop yields are crucial for the food security of small-scale farmers and not whether a method is more efficient or not. Although humus can be enriched under no-tillage, the sequestration of soil carbon, is result of the accumulated organic matter in the topsoil, is restricted to the upper 10 cm of the soil. Compared with ploughing, no carbon benefi t – or even a carbon defi cit – has been found at soil depths below 20 cm. This is why no-till makes little or no contribution to carbon sequestration and does not prove to reduce greenhouse gas emissions in croplands. The quantifi cation of carbon sequestration rates under no-till are highly doubtful. Anyhow, it is very likely that emission reductions generated from no-till projects in developing countries would serve to offset emissions from he industry and transport sector in developed countries. Those well quantifi ed emissions from developed countries would thus be offset by uncertain reductions from agriculture projects. The overall aim of the UNFCCC – to avoid dangerous climate change – would be jeopardized. Even if no-till became a promising mitigation option, other environmental problems would remain. No-till farming systems often come along with the industrialization of agriculture with high inputs of agrochemicals. On the one hand, small-scale farmers are not skilled in handling such chemicals. On the other hand there remains a risk that they apply cheap chemicals, which persist long-term in the environment. Efforts should therefore be strengthened on how to combine sustainable production systems such as organic agriculture with no-till practices. To summarize, there are too many open questions and uncertainties concerning the impact of no-till on crop yields and carbon sequestration, so that no-till could not be sold as the solution for hunger reduction and adequate option to mitigate climate change but as an important part of integrated strategies. Therefore, we recommend keeping no-till and reduced till out of the carbon market unless reliable carbon offset quantifi cation and monitoring can be undertaken at reasonable cost

Influence of notillage on carbon sequestration and erosion in Brazil

Les sols constituent le plus gros réservoir superficiel de C (hors les roches carbonatées), environ 1500 Gt C, ce qui équivaut à presque trois fois la quantité stockée dans la biomasse terrestre, et deux fois celle de l'atmosphère. Toute modification de l'usage des terres et, même pour les systèmes agricoles à l'équilibre, toute modification de l'itinéraire technique, peut induire des variations du stockage du carbone dans les sols. Les pratiques de labour favorisent souvent une aération du sol, qui est propice à l'activité microbienne et conduisent à une dégradation de la structure. Il en résulte sur le moyen et long terme une minéralisation accrue de la matière organique du sol. Du fait de l'absence (ou limitation) des travaux du sol (No-tillage, NT) et d'un maintien d'une couverture végétale permanente (DMC), les systèmes de semis direct favoriseraient la séquestration du carbone et limiteraient l'érosion. Au Brésil, l'apparition du semi-direct dans la Région Sud, au Paraná date du début des années 1970. Un des objectifs majeurs de l'époque était la lutte contre l'érosion, puis les recherches se sont développées vers la gestion des résidus de récolte et leur effet sur la fertilité, que ce soit pour la gestion du phosphore, le contrôle de l'acidité ou la localisation des engrais. Cette pratique, qui a pris une grande extension et continue de s'accroître dans le centre et le nord du pays, occupe actuellement entre environ 18 millions d'hectares avec une très grande diversité de milieux, d'agrosystèmes et d'itinéraires techniques. Au Brésil, la plus part des auteurs donnent des vitesses de stockage du carbone dans des sols sous semis-direct allant de 0,4 à 1,7 t C/ha/yr pour la couche 0-40 cm, avec les taux les plus élevés pour la région centrale du Cerrado. Mais certaines précautions sont nécessaires lors de la comparaison, en terme de séquestration du carbone, des systèmes de semis direct avec les systèmes labourés. Les comparaisons ne doivent pas se limiter au seul stockage de carbone dans le sol, mais doivent prendre compte les changements dans les émissions de méthane et d'oxyde nitreux qui sont des gaz à effet de serres importants. L'adoption des techniques de semis-direct s'accompagne d'une diminution des pertes en sol par érosion de l'ordre de 90% et du ruissellement superficiel de l'ordre de 70%. Ce qui évite ainsi la perte de nutriments qui sont souvent en quantité limite dans les sols du Brésil. Le succès des techniques de semis-direct au Brésil est dû historiquement au contrôle de la fertilité des sols qui est assuré surtout par la préservation de la ressource sol. Plus récemment, ce succès est amplifié par la préservation de la ressource carbone. (Résumé d'auteur

High Sequestration, Low Emission, Food Secure Farming. Organic Agriculture - a Guide to Climate Change & Food Security

- affordable high sequestration practices based on local resources - enables continuous farmer-based adaptation to climate change - ideal for the improvement of the world’s 400 million smallholder farms - locally adapted, affordable and people centered - empowers local communities - established practices, systems and markets - experience, practices and expertise to shar

Mycorrhizas and biomass crops: opportunities for future sustainable development

Central to soil health and plant productivity in natural ecosystems are in situ soil microbial communities, of which mycorrhizal fungi are an integral component, regulating nutrient transfer between plants and the surrounding soil via extensive mycelial networks. Such networks are supported by plant-derived carbon and are likely to be enhanced under coppiced biomass plantations, a forestry practice that has been highlighted recently as a viable means of providing an alternative source of energy to fossil fuels, with potentially favourable consequences for carbon mitigation. Here, we explore ways in which biomass forestry, in conjunction with mycorrhizal fungi, can offer a more holistic approach to addressing several topical environmental issues, including ‘carbon-neutral’ energy, ecologically sustainable land management and CO2 sequestration

Fertiliser use and soil carbon sequestration: Key messages for climate change mitigation strategies

Reducing greenhouse gas (GHG) emissions and increasing soil or biomass carbon stocks are the main agricultural pathways to mitigate climate change. Scientific and policy attention has recently turned to evaluating the potential of practices that can increase soil carbon sequestration. Forty percent of the world’s soils are used as cropland and grassland, therefore agricultural policies and practices are critical to maintaining or increasing the global soil carbon pool. This info note explains the current understanding of the impact of mineral fertiliser use on soil carbon sequestration as a mitigation strategy in agriculture. The science and understanding on soil carbon sequestration and mitigation is still emerging, especially in tropical regions. Taking this into consideration, this info note discusses related effects of fertiliser use on climate change mitigation, such as nitrous oxide (N2O) and carbon dioxide (CO2) emissions from nitrogen fertiliser use and production, and the potential effects of mineral fertiliser use on land use change