Trade-based carbon sequestration accounting.

PubMed

King, Dennis M

2004-04-01

This article describes and illustrates an accounting method to assess and compare "early" carbon sequestration investments and trades on the basis of the number of standardized CO2 emission offset credits they will provide. The "gold standard" for such credits is assumed to be a relatively riskless credit based on a CO2 emission reduction that provides offsets against CO2 emissions on a one-for-one basis. The number of credits associated with carbon sequestration needs to account for time, risk, durability, permanence, additionality, and other factors that future trade regulators will most certainly use to assign "official" credits to sequestration projects. The method that is presented here uses established principles of natural resource accounting and conventional rules of asset valuation to "score" projects. A review of 20 "early" voluntary United States based CO2 offset trades that involve carbon sequestration reveals that the assumptions that buyers, sellers, brokers, and traders are using to characterize the economic potential of their investments and trades vary enormously. The article develops a "universal carbon sequestration credit scoring equation" and uses two of these trades to illustrate the sensitivity of trade outcomes to various assumptions about how future trade auditors are likely to "score" carbon sequestration projects in terms of their "equivalency" with CO2 emission reductions. The article emphasizes the importance of using a standard credit scoring method that accounts for time and risk to assess and compare even unofficial prototype carbon sequestration trades. The scoring method illustrated in this article is a tool that can protect the integrity of carbon sequestration credit trading and can assist buyers and sellers in evaluating the real economic potential of prospective trades.

Physical and Economic Integration of Carbon Capture Methods with Sequestration Sinks

NASA Astrophysics Data System (ADS)

Murrell, G. R.; Thyne, G. D.

2007-12-01

Currently there are several different carbon capture technologies either available or in active development for coal- fired power plants. Each approach has different advantages, limitations and costs that must be integrated with the method of sequestration and the physiochemical properties of carbon dioxide to evaluate which approach is most cost effective. For large volume point sources such as coal-fired power stations, the only viable sequestration sinks are either oceanic or geological in nature. However, the carbon processes and systems under consideration produce carbon dioxide at a variety of pressure and temperature conditions that must be made compatible with the sinks. Integration of all these factors provides a basis for meaningful economic comparisons between the alternatives. The high degree of compatibility between carbon dioxide produced by integrated gasification combined cycle technology and geological sequestration conditions makes it apparent that this coupling currently holds the advantage. Using a basis that includes complete source-to-sink sequestration costs, the relative cost benefit of pre-combustion IGCC compared to other post-combustion methods is on the order of 30%. Additional economic benefits arising from enhanced oil recovery revenues and potential sequestration credits further improve this coupling.

An Index-Based Approach to Assessing Recalcitrance and Soil Carbon Sequestration Potential of Engineered Black Carbons (Biochars)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harvey, Omar R.; Kuo, Li-Jung; Zimmerman, Andrew R.

2012-01-10

The ability of engineered black carbons (or biochars) to resist abiotic and, or biotic degradation (herein referred to as recalcitrance) is crucial to their successful deployment as a soil carbon sequestration strategy. A new recalcitrance index, the R{sub 50}, for assessing biochar quality for carbon sequestration is proposed. The R{sub 50} is based on the relative thermal stability of a given biochar to that of graphite and was developed and evaluated with a variety of biochars (n = 59), and soot-like black carbons. Comparison of R{sub 50}, with biochar physicochemical properties and biochar-C mineralization revealed the existence of a quantifiablemore » relationship between R{sub 50} and biochar recalcitrance. As presented here, the R{sub 50} is immediately applicable to pre-land application screening of biochars into Class A (R{sub 50} {>=} 0.70), Class B (0.50 {<=} R{sub 50} < 0.70) or Class C (R{sub 50} < 0.50) recalcitrance/carbon sequestration classes. Class A and Class C biochars would have carbon sequestration potential comparable to soot/graphite and uncharred plant biomass, respectively, while Class B biochars would have intermediate carbon sequestration potential. We believe that the coupling of the R{sub 50}, to an index-based degradation, and an economic model could provide a suitable framework in which to comprehensively assess soil carbon sequestration in biochars.« less

Carbon sequestration potential of soils in southeast Germany derived from stable soil organic carbon saturation.

PubMed

Wiesmeier, Martin; Hübner, Rico; Spörlein, Peter; Geuß, Uwe; Hangen, Edzard; Reischl, Arthur; Schilling, Bernd; von Lützow, Margit; Kögel-Knabner, Ingrid

2014-02-01

Sequestration of atmospheric carbon (C) in soils through improved management of forest and agricultural land is considered to have high potential for global CO2 mitigation. However, the potential of soils to sequester soil organic carbon (SOC) in a stable form, which is limited by the stabilization of SOC against microbial mineralization, is largely unknown. In this study, we estimated the C sequestration potential of soils in southeast Germany by calculating the potential SOC saturation of silt and clay particles according to Hassink [Plant and Soil 191 (1997) 77] on the basis of 516 soil profiles. The determination of the current SOC content of silt and clay fractions for major soil units and land uses allowed an estimation of the C saturation deficit corresponding to the long-term C sequestration potential. The results showed that cropland soils have a low level of C saturation of around 50% and could store considerable amounts of additional SOC. A relatively high C sequestration potential was also determined for grassland soils. In contrast, forest soils had a low C sequestration potential as they were almost C saturated. A high proportion of sites with a high degree of apparent oversaturation revealed that in acidic, coarse-textured soils the relation to silt and clay is not suitable to estimate the stable C saturation. A strong correlation of the C saturation deficit with temperature and precipitation allowed a spatial estimation of the C sequestration potential for Bavaria. In total, about 395 Mt CO2 -equivalents could theoretically be stored in A horizons of cultivated soils - four times the annual emission of greenhouse gases in Bavaria. Although achieving the entire estimated C storage capacity is unrealistic, improved management of cultivated land could contribute significantly to CO2 mitigation. Moreover, increasing SOC stocks have additional benefits with respect to enhanced soil fertility and agricultural productivity. © 2013 John Wiley & Sons Ltd.

A Review of Major Non-Power-Related Carbon Dioxide Stream Compositions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Last, George V.; Schmick, Mary T.

A critical component in the assessment of long-term risk from geologic sequestration of carbon dioxide (CO2) is the ability to predict mineralogical and geochemical changes within storage reservoirs as a result of rock-brine-CO2 reactions. Impurities and/or other constituents in CO2 source streams selected for sequestration can affect both the chemical and physical (e.g., density, viscosity, interfacial tension) properties of CO2 in the deep subsurface. The nature and concentrations of these impurities are a function of both the industrial source(s) of CO2, as well as the carbon capture technology used to extract the CO2 and produce a concentrated stream for subsurfacemore » injection and geologic sequestration. This article reviews the relative concentrations of CO2 and other constituents in exhaust gases from major non-energy-related industrial sources of CO2. Assuming that carbon capture technology would remove most of the incondensable gases N2, O2, and Ar, leaving SO2 and NOx as the main impurities, the authors then summarize the relative proportions of the remaining impurities assumed to be present in CO2 source streams that could be targeted for geologic sequestration. The summary is presented relative to five potential sources of CO2: 1) Flue Gas with Flue Gas Desulfurization, 2) Combustion Stack from Coke Production, 3) Portland Cement Kilns, 4) Natural Gas Combustion, and 5) Lime Production.« less

Multiphase modeling of geologic carbon sequestration in saline aquifers.

PubMed

Bandilla, Karl W; Celia, Michael A; Birkholzer, Jens T; Cihan, Abdullah; Leister, Evan C

2015-01-01

Geologic carbon sequestration (GCS) is being considered as a climate change mitigation option in many future energy scenarios. Mathematical modeling is routinely used to predict subsurface CO2 and resident brine migration for the design of injection operations, to demonstrate the permanence of CO2 storage, and to show that other subsurface resources will not be degraded. Many processes impact the migration of CO2 and brine, including multiphase flow dynamics, geochemistry, and geomechanics, along with the spatial distribution of parameters such as porosity and permeability. In this article, we review a set of multiphase modeling approaches with different levels of conceptual complexity that have been used to model GCS. Model complexity ranges from coupled multiprocess models to simplified vertical equilibrium (VE) models and macroscopic invasion percolation models. The goal of this article is to give a framework of conceptual model complexity, and to show the types of modeling approaches that have been used to address specific GCS questions. Application of the modeling approaches is shown using five ongoing or proposed CO2 injection sites. For the selected sites, the majority of GCS models follow a simplified multiphase approach, especially for questions related to injection and local-scale heterogeneity. Coupled multiprocess models are only applied in one case where geomechanics have a strong impact on the flow. Owing to their computational efficiency, VE models tend to be applied at large scales. A macroscopic invasion percolation approach was used to predict the CO2 migration at one site to examine details of CO2 migration under the caprock. © 2015, National Ground Water Association.

In Brief: Carbon Sequestration Partnerships; Review of Peer Reviews

NASA Astrophysics Data System (ADS)

Showstack, Randy

The U.S. Department of Energy named seven regional partnerships on 16 August to study the best methods for the non-biological sequestration of carbon in different parts of the country.Peer review guidelines for science issued by the federal government which is related to regulatory topics could be tightened up under a 29 August White House proposal.

Determining landscape-level carbon emissions from historically harvested forest products

Treesearch

Sean Healey; Todd Morgan; Jon Songster; Jason Brandt

2009-01-01

Resources have been developed in the literature to enable landowners to estimate the carbon sequestration timeline of forest products derived from their land. These tools were used here to estimate sequestration and emissions related to harvests carried out in Ravalli County from 1945 to 2007. This county-level accounting of product carbon release can later be combined...

Poromechanical behaviour of a surficial geological barrier during fluid injection into an underlying poroelastic storage formation

PubMed Central

Selvadurai, A. P. S.; Kim, Jueun

2016-01-01

A competent low permeability and chemically inert geological barrier is an essential component of any strategy for the deep geological disposal of fluidized hazardous material and greenhouse gases. While the processes of injection are important to the assessment of the sequestration potential of the storage formation, the performance of the caprock is important to the containment potential, which can be compromised by the development of cracks and other defects that might be activated during and after injection. This paper presents a mathematical modelling approach that can be used to assess the state of stress in a surficial caprock during injection of a fluid to the interior of a poroelastic storage formation. Important information related to time-dependent evolution of the stress state and displacements of the surficial caprock with injection rates, and the stress state in the storage formation can be obtained from the theoretical developments. Most importantly, numerical results illustrate the influence of poromechanics on the development of adverse stress states in the geological barrier. The results obtained from the mathematical analysis illustrate that the surface heave increases as the hydraulic conductivity of the caprock decreases, whereas the surface heave decreases as the shear modulus of the caprock increases. The results also illustrate the influence of poromechanics on the development of adverse stress states in the caprock. PMID:27118906

Poromechanical behaviour of a surficial geological barrier during fluid injection into an underlying poroelastic storage formation.

PubMed

Selvadurai, A P S; Kim, Jueun

2016-03-01

A competent low permeability and chemically inert geological barrier is an essential component of any strategy for the deep geological disposal of fluidized hazardous material and greenhouse gases. While the processes of injection are important to the assessment of the sequestration potential of the storage formation, the performance of the caprock is important to the containment potential, which can be compromised by the development of cracks and other defects that might be activated during and after injection. This paper presents a mathematical modelling approach that can be used to assess the state of stress in a surficial caprock during injection of a fluid to the interior of a poroelastic storage formation. Important information related to time-dependent evolution of the stress state and displacements of the surficial caprock with injection rates, and the stress state in the storage formation can be obtained from the theoretical developments. Most importantly, numerical results illustrate the influence of poromechanics on the development of adverse stress states in the geological barrier. The results obtained from the mathematical analysis illustrate that the surface heave increases as the hydraulic conductivity of the caprock decreases, whereas the surface heave decreases as the shear modulus of the caprock increases. The results also illustrate the influence of poromechanics on the development of adverse stress states in the caprock.

Bayesian-information-gap decision theory with an application to CO 2 sequestration

DOE PAGES

O'Malley, D.; Vesselinov, V. V.

2015-09-04

Decisions related to subsurface engineering problems such as groundwater management, fossil fuel production, and geologic carbon sequestration are frequently challenging because of an overabundance of uncertainties (related to conceptualizations, parameters, observations, etc.). Because of the importance of these problems to agriculture, energy, and the climate (respectively), good decisions that are scientifically defensible must be made despite the uncertainties. We describe a general approach to making decisions for challenging problems such as these in the presence of severe uncertainties that combines probabilistic and non-probabilistic methods. The approach uses Bayesian sampling to assess parametric uncertainty and Information-Gap Decision Theory (IGDT) to addressmore » model inadequacy. The combined approach also resolves an issue that frequently arises when applying Bayesian methods to real-world engineering problems related to the enumeration of possible outcomes. In the case of zero non-probabilistic uncertainty, the method reduces to a Bayesian method. Lastly, to illustrate the approach, we apply it to a site-selection decision for geologic CO 2 sequestration.« less

Developing a Robust Geochemical and Reactive Transport Model to Evaluate Possible Sources of Arsenic at the CO2 Sequestration Natural Analog Site in Chimayo, New Mexico

EPA Science Inventory

Migration of carbon dioxide (CO₂) from deep storage formations into shallow drinking water aquifers is a possible system failure related to geologic CO₂ sequestration. A CO₂ leak may cause mineral precipitation/dissolution reactions, changes in a...

Molecular pharmacodynamics of emixustat in protection against retinal degeneration

PubMed Central

Zhang, Jianye; Kiser, Philip D.; Badiee, Mohsen; Palczewska, Grazyna; Dong, Zhiqian; Golczak, Marcin; Tochtrop, Gregory P.; Palczewski, Krzysztof

2015-01-01

Emixustat is a visual cycle modulator that has entered clinical trials as a treatment for age-related macular degeneration (AMD). This molecule has been proposed to inhibit the visual cycle isomerase RPE65, thereby slowing regeneration of 11-cis-retinal and reducing production of retinaldehyde condensation byproducts that may be involved in AMD pathology. Previously, we reported that all-trans-retinal (atRAL) is directly cytotoxic and that certain primary amine compounds that transiently sequester atRAL via Schiff base formation ameliorate retinal degeneration. Here, we have shown that emixustat stereoselectively inhibits RPE65 by direct active site binding. However, we detected the presence of emixustat-atRAL Schiff base conjugates, indicating that emixustat also acts as a retinal scavenger, which may contribute to its therapeutic effects. Using agents that lack either RPE65 inhibitory activity or the capacity to sequester atRAL, we assessed the relative importance of these 2 modes of action in protection against retinal phototoxicity in mice. The atRAL sequestrant QEA-B-001-NH2 conferred protection against phototoxicity without inhibiting RPE65, whereas an emixustat derivative incapable of atRAL sequestration was minimally protective, despite direct inhibition of RPE65. These data indicate that atRAL sequestration is an essential mechanism underlying the protective effects of emixustat and related compounds against retinal phototoxicity. Moreover, atRAL sequestration should be considered in the design of next-generation visual cycle modulators. PMID:26075817

Sequestration and Distribution Characteristics of Cd(II) by Microcystis aeruginosa and Its Role in Colony Formation.

PubMed

Bi, Xiangdong; Yan, Ran; Li, Fenxiang; Dai, Wei; Jiao, Kewei; Zhou, Qixing; Liu, Qi

2016-01-01

To investigate the sequestration and distribution characteristics of Cd(II) by Microcystis aeruginosa and its role in Microcystis colony formation, M. aeruginosa was exposed to six different Cd(II) concentrations for 10 days. Cd(II) exposure caused hormesis in the growth of M. aeruginosa . Low concentrations of Cd(II) significantly induced formation of small Microcystis colonies ( P < 0.05) and increased the intracellular polysaccharide (IPS) and bound extracellular polysaccharide (bEPS) contents of M. aeruginosa significantly ( P < 0.05). There was a linear relationship between the amount of Cd(II) sequestrated by algal cells and the amount added to cultures in the rapid adsorption process that occurred during the first 5 min of exposure. After 10 d, M. aeruginosa sequestrated nearly 80% of 0.2 mg L -1 added Cd(II), while >93% of Cd(II) was sequestrated in the groups with lower added concentrations of Cd(II). More than 80% of the sequestrated Cd(II) was bioadsorbed by bEPS. The Pearson correlation coefficients of exterior and interior factors related to colony formation of M. aeruginosa revealed that Cd(II) could stimulate the production of IPS and bEPS via increasing Cd(II) bioaccumulation and bioadsorption. Increased levels of cross-linking between Cd(II) and bEPS stimulated algal cell aggregation, which eventually promoted the formation of Microcystis colonies.

Sequestration and Distribution Characteristics of Cd(II) by Microcystis aeruginosa and Its Role in Colony Formation

PubMed Central

Bi, Xiangdong; Yan, Ran; Li, Fenxiang; Dai, Wei; Jiao, Kewei; Liu, Qi

2016-01-01

To investigate the sequestration and distribution characteristics of Cd(II) by Microcystis aeruginosa and its role in Microcystis colony formation, M. aeruginosa was exposed to six different Cd(II) concentrations for 10 days. Cd(II) exposure caused hormesis in the growth of M. aeruginosa. Low concentrations of Cd(II) significantly induced formation of small Microcystis colonies (P < 0.05) and increased the intracellular polysaccharide (IPS) and bound extracellular polysaccharide (bEPS) contents of M. aeruginosa significantly (P < 0.05). There was a linear relationship between the amount of Cd(II) sequestrated by algal cells and the amount added to cultures in the rapid adsorption process that occurred during the first 5 min of exposure. After 10 d, M. aeruginosa sequestrated nearly 80% of 0.2 mg L−1 added Cd(II), while >93% of Cd(II) was sequestrated in the groups with lower added concentrations of Cd(II). More than 80% of the sequestrated Cd(II) was bioadsorbed by bEPS. The Pearson correlation coefficients of exterior and interior factors related to colony formation of M. aeruginosa revealed that Cd(II) could stimulate the production of IPS and bEPS via increasing Cd(II) bioaccumulation and bioadsorption. Increased levels of cross-linking between Cd(II) and bEPS stimulated algal cell aggregation, which eventually promoted the formation of Microcystis colonies. PMID:27777956

Carbon Sequestration: is Science Leading Policy or Will Policy Direct Science?

NASA Astrophysics Data System (ADS)

Anderson, A. K.

2007-12-01

Climate-related policy is in its infancy on capital hill, as policy makers only recently started to converge on the acceptance that climate change is a credible, scientific reality. Until recently much of the debate and policy decisions have been related to whether or not climate change, or more specifically global warming, is occurring. The climate debate has shifted from discussing the science behind climate change to addressing how we can reduce carbon dioxide emissions. In the 110th Congress, policy makers have come to realize and accept that we, as a nation, are one of the largest global emitters of carbon dioxide to the atmosphere. Geologic carbon sequestration has gained significant congressional attention and is considered to be one of the most promising carbon mitigation tools. In the present Congress, scientific experts have testified before numerous committees about the various caveats of geologic carbon sequestration. As a result, policy has been and is currently being drafted to address the challenges facing large-scale commercial demonstration of geologic sequestration facilities. Policy has been passed through both the House and Senate that is aimed at increasing funding for basic and advanced research, development, and demonstration of small- to large-scale carbon dioxide injection projects. This legislation is only the beginning of a series of legislation that is under development. In the next year, policy will be introduced that will likely address issues related to pore space and mineral rights ownership, regulatory framework for carbon dioxide transport and injection, long-term injection site monitoring protocol, personal and environmental safety, and liability issues, to name a few. Policy is not limited to the technical aspects of carbon capture, transport, and storage, but is also being developed to help stimulate a market that will be operating under climate constraints. Financial incentives have been proposed that will assist industrial carbon dioxide emitters in making the transition into a carbon-constrained economy. Science has driven the initial policy that has been proposed to date; however, the topic of carbon sequestration has been advanced through Congress at a near record-breaking pace. As such, there is an increased need to hear from scientists in academia and industry alike to continue to make good policy decisions related to carbon sequestration based on sound scientific advice.

Eddy Covariance Method for CO2 Emission Measurements: CCS Applications, Principles, Instrumentation and Software

NASA Astrophysics Data System (ADS)

Burba, George; Madsen, Rod; Feese, Kristin

2013-04-01

The Eddy Covariance method is a micrometeorological technique for direct high-speed measurements of the transport of gases, heat, and momentum between the earth's surface and the atmosphere. Gas fluxes, emission and exchange rates are carefully characterized from single-point in-situ measurements using permanent or mobile towers, or moving platforms such as automobiles, helicopters, airplanes, etc. Since the early 1990s, this technique has been widely used by micrometeorologists across the globe for quantifying CO2 emission rates from various natural, urban and agricultural ecosystems [1,2], including areas of agricultural carbon sequestration. Presently, over 600 eddy covariance stations are in operation in over 120 countries. In the last 3-5 years, advancements in instrumentation and software have reached the point when they can be effectively used outside the area of micrometeorology, and can prove valuable for geological carbon capture and sequestration, landfill emission measurements, high-precision agriculture and other non-micrometeorological industrial and regulatory applications. In the field of geological carbon capture and sequestration, the magnitude of CO2 seepage fluxes depends on a variety of factors. Emerging projects utilize eddy covariance measurement to monitor large areas where CO2 may escape from the subsurface, to detect and quantify CO2 leakage, and to assure the efficiency of CO2 geological storage [3,4,5,6,7,8]. Although Eddy Covariance is one of the most direct and defensible ways to measure and calculate turbulent fluxes, the method is mathematically complex, and requires careful setup, execution and data processing tailor-fit to a specific site and a project. With this in mind, step-by-step instructions were created to introduce a novice to the conventional Eddy Covariance technique [9], and to assist in further understanding the method through more advanced references such as graduate-level textbooks, flux networks guidelines, journals and technical papers. A free open-source software package with a user-friendly interface was developed accordingly for computing final fully corrected CO2 emission numbers [10]. The presentation covers highlights of the eddy covariance method, its application to geological carbon sequestration, key requirements, instrumentation and software, and reviews educational resources particularly useful for carbon sequestration research. References: [1] Aubinet, M., T. Vesala, and D. Papale (Eds.), 2012. Eddy Covariance: A Practical Guide to Measurement and Data Analysis. Springer-Verlag, 442 pp. [2] Foken T., 2008. Micrometeorology. Springer-Verlag, 308 pp. [4] Finley, R., 2009. An Assessment of Geological Carbon Sequestration in the Illinois Basin Overview of the Decatur-Illinois Basin Site. MGSC, http://www.istc.illinois.edu/info/govs_awards_docs/2009-GSA-1100-Finley.pdf [5] Liu, G. (Ed.), 2012. Greenhouse Gases: Capturing, Utilization and Reduction. Intech, 338 pp. [6] LI-COR Biosciences, 2011. Surface Monitoring for Geologic Carbon Sequestration Monitoring: Methods, Instrumentation, and Case Studies. LI-COR Biosciences, Pub. 980-11916, 15 pp. [7] Benson, S., 2006. Monitoring carbon dioxide sequestration in deep geological formations for inventory verification and carbon credits, SPE-102833, Presentation [8] Lewicki, J., G. Hilley, M. Fischer, L. Pan, C. Olden-burg, C. Dobeck, and L. Spangler, 2009.Eddy covariance observations of leakage during shallow subsurface CO2 releases. Journal of Geophys Res, 114: D12302 [9] Burba, G., 2013. Eddy Covariance Method for Scientific, Industrial, Agricultural and Regulatory Applications. LI-COR Biosciences, 328 pp. [10] LI-COR Biosciences, 2012. EddyPro 4.0: Help and User's Guide. Lincoln, NE, 208 pp.

How organic carbon derived from multiple sources contributes to carbon sequestration processes in a shallow coastal system?

PubMed Central

Watanabe, Kenta; Kuwae, Tomohiro

2015-01-01

Carbon captured by marine organisms helps sequester atmospheric CO2, especially in shallow coastal ecosystems, where rates of primary production and burial of organic carbon (OC) from multiple sources are high. However, linkages between the dynamics of OC derived from multiple sources and carbon sequestration are poorly understood. We investigated the origin (terrestrial, phytobenthos derived, and phytoplankton derived) of particulate OC (POC) and dissolved OC (DOC) in the water column and sedimentary OC using elemental, isotopic, and optical signatures in Furen Lagoon, Japan. Based on these data analysis, we explored how OC from multiple sources contributes to sequestration via storage in sediments, water column sequestration, and air–sea CO2 exchanges, and analyzed how the contributions vary with salinity in a shallow seagrass meadow as well. The relative contribution of terrestrial POC in the water column decreased with increasing salinity, whereas autochthonous POC increased in the salinity range 10–30. Phytoplankton-derived POC dominated the water column POC (65–95%) within this salinity range; however, it was minor in the sediments (3–29%). In contrast, terrestrial and phytobenthos-derived POC were relatively minor contributors in the water column but were major contributors in the sediments (49–78% and 19–36%, respectively), indicating that terrestrial and phytobenthos-derived POC were selectively stored in the sediments. Autochthonous DOC, part of which can contribute to long-term carbon sequestration in the water column, accounted for >25% of the total water column DOC pool in the salinity range 15–30. Autochthonous OC production decreased the concentration of dissolved inorganic carbon in the water column and thereby contributed to atmospheric CO2 uptake, except in the low-salinity zone. Our results indicate that shallow coastal ecosystems function not only as transition zones between land and ocean but also as carbon sequestration filters. They function at different timescales, depending on the salinity, and OC sources. PMID:25880367

Carbon storage and sequestration by trees in urban and community areas of the United States

Treesearch

David J. Nowak; Eric J. Greenfield; Robert E. Hoehn; Elizabeth Lapoint

2013-01-01

Carbon storage and sequestration by urban trees in the United States was quantified to assess the magnitude and role of urban forests in relation to climate change. Urban tree field data from 28 cities and 6 states were used to determine the average carbon density per unit of tree cover. These data were applied to statewide urban tree cover measurements to determine...

[Bone sequestration in alpacas in Germany - A practice report with 12 cases].

PubMed

Kobera, Ralph; Wagner, Henrik

2018-04-01

Bone sequestration is relatively unknown in New-world camelids in Germany and is frequently wrongly addressed as neoplasia by veterinary practitioners. This clinical case report describes diagnosis and treatment for bone sequestration in alpacas based on 12 cases. The main symptom of the presented alpacas was moderate to severe lameness in one limb. Some of the patients had been treated with nonsteroidal anti-inflammatory drugs by the referring veterinarian. In eight alpacas, palpation of the swelling in the affected leg was painful and in five animals, exudation was observed. Radiographic imaging led to a correct diagnosis in all of the cases. Following surgical removal of the bone sequestrum, the lameness was already noticeably improved by the third postoperative day. In all patients, healing was achieved without any complications. These results show that bone sequestration in alpacas can be treated successfully by timely surgery. This is the first case report on this topic in alpacas in Germany. Schattauer GmbH.

Federal Control of Geological Carbon Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reitze, Arnold W.

The United States has economically recoverable coal reserves of about 261 billion tons, which is in excess of a 250-­year supply based on 2009 consumption rates. However, in the near future the use of coal may be legally restricted because of concerns over the effects of its combustion on atmospheric carbon dioxide concentrations. In response, the U.S. Department of Energy is making significant efforts to help develop and implement a commercial scale program of geologic carbon sequestration that involves capturing and storing carbon dioxide emitted from coal-burning electric power plants in deep underground formations. This article explores the technical andmore » legal problems that must be resolved in order to have a viable carbon sequestration program. It covers the responsibilities of the United States Environmental Protection Agency and the Departments of Energy, Transportation and Interior. It discusses the use of the Safe Drinking Water Act, the Clean Air Act, the National Environmental Policy Act, the Endangered Species Act, and other applicable federal laws. Finally, it discusses the provisions related to carbon sequestration that have been included in the major bills dealing with climate change that Congress has been considering in 2009 and 2010. The article concludes that the many legal issues that exist can be resolved, but whether carbon sequestration becomes a commercial reality will depend on reducing its costs or by imposing legal requirements on fossil-fired power plants that result in the costs of carbon emissions increasing to the point that carbon sequestration becomes a feasible option.« less

Nitrogen-Related Constraints of Carbon Uptake by Large-Scale Forest Expansion: Simulation Study for Climate Change and Management Scenarios

NASA Astrophysics Data System (ADS)

Kracher, Daniela

2017-11-01

Increase of forest areas has the potential to increase the terrestrial carbon (C) sink. However, the efficiency for C sequestration depends on the availability of nutrients such as nitrogen (N), which is affected by climatic conditions and management practices. In this study, I analyze how N limitation affects C sequestration of afforestation and how it is influenced by individual climate variables, increased harvest, and fertilizer application. To this end, JSBACH, the land component of the Earth system model of the Max Planck Institute for Meteorology is applied in idealized simulation experiments. In those simulations, large-scale afforestation increases the terrestrial C sink in the 21st century by around 100 Pg C compared to a business as usual land-use scenario. N limitation reduces C sequestration roughly by the same amount. The relevance of compensating effects of uptake and release of carbon dioxide by plant productivity and soil decomposition, respectively, gets obvious from the simulations. N limitation of both fluxes compensates particularly in the tropics. Increased mineralization under global warming triggers forest expansion, which otherwise is restricted by N availability. Due to compensating higher plant productivity and soil respiration, the global net effect of warming for C sequestration is however rather small. Fertilizer application and increased harvest enhance C sequestration as well as boreal expansion. The additional C sequestration achieved by fertilizer application is offset to a large part by additional emissions of nitrous oxide.

Quantitative assessment of carbon sequestration reduction induced by disturbances in temperate Eurasian steppe

NASA Astrophysics Data System (ADS)

Chen, Yizhao; Ju, Weimin; Groisman, Pavel; Li, Jianlong; Propastin, Pavel; Xu, Xia; Zhou, Wei; Ruan, Honghua

2017-11-01

The temperate Eurasian steppe (TES) is a region where various environmental, social, and economic stresses converge. Multiple types of disturbance exist widely across the landscape, and heavily influence carbon cycling in this region. However, a current quantitative assessment of the impact of disturbances on carbon sequestration is largely lacking. In this study, we combined the boreal ecosystem productivity simulator (BEPS), the Shiyomi grazing model, and the global fire model (Glob-FIRM) to investigate the impact of the two major types of disturbance in the TES (i.e. domestic grazing and fire) on regional carbon sequestration. Model performance was validated using satellite data and field observations. Model outputs indicate that disturbance has a significant impact on carbon sequestration at a regional scale. The annual total carbon lost due to disturbances was 7.8 TgC yr-1, accounting for 14.2% of the total net ecosystem productivity (NEP). Domestic grazing plays the dominant role in terrestrial carbon consumption, accounting for 95% of the total carbon lost from the two disturbances. Carbon losses from both disturbances significantly increased from 1999 to 2008 (R 2 = 0.82, P < 0.001 for grazing, R 2 = 0.51, P < 0.05 for fire). Heavy domestic grazing in relatively barren grasslands substantially reduced carbon sequestration, particularly in the grasslands of Turkmenistan, Uzbekistan, and the far southwest of Inner Mongolia. This spatially-explicit information has potential implications for sustainable management of carbon sequestration in the vast grassland ecosystems.

Impacts of urban forests on offsetting carbon emissions from industrial energy use in Hangzhou, China.

PubMed

Zhao, Min; Kong, Zheng-hong; Escobedo, Francisco J; Gao, Jun

2010-01-01

This study quantified carbon storage and sequestration by urban forests and carbon emissions from energy consumption by several industrial sources in Hangzhou, China. Carbon (C) storage and sequestration were quantified using urban forest inventory data and by applying volume-derived biomass equations and other models relating net primary productivity (NPP) and mean annual biomass increments. Industrial energy use C emissions were estimated by accounting for fossil fuel use and assigning C emission factors. Total C storage by Hangzhou's urban forests was estimated at 11.74 Tg C, and C storage per hectare was 30.25 t C. Carbon sequestration by urban forests was 1,328, 166.55 t C/year, and C sequestration per ha was 1.66 t C/ha/year. Carbon emissions from industrial energy use in Hangzhou were 7 Tg C/year. Urban forests, through sequestration, annually offset 18.57% of the amount of carbon emitted by industrial enterprises, and store an amount of C equivalent to 1.75 times the amount of annual C emitted by industrial energy uses within the city. Management practices for improving Hangzhou's urban forests function of offsetting C emissions from energy consumption are explored. These results can be used to evaluate the urban forests' role in reducing atmospheric carbon dioxide. Copyright 2009 Elsevier Ltd. All rights reserved.

Carbon storage capacity of semi-arid grassland soils and sequestration potentials in northern China.

PubMed

Wiesmeier, Martin; Munro, Sam; Barthold, Frauke; Steffens, Markus; Schad, Peter; Kögel-Knabner, Ingrid

2015-10-01

Organic carbon (OC) sequestration in degraded semi-arid environments by improved soil management is assumed to contribute substantially to climate change mitigation. However, information about the soil organic carbon (SOC) sequestration potential in steppe soils and their current saturation status remains unknown. In this study, we estimated the OC storage capacity of semi-arid grassland soils on the basis of remote, natural steppe fragments in northern China. Based on the maximum OC saturation of silt and clay particles <20 μm, OC sequestration potentials of degraded steppe soils (grazing land, arable land, eroded areas) were estimated. The analysis of natural grassland soils revealed a strong linear regression between the proportion of the fine fraction and its OC content, confirming the importance of silt and clay particles for OC stabilization in steppe soils. This relationship was similar to derived regressions in temperate and tropical soils but on a lower level, probably due to a lower C input and different clay mineralogy. In relation to the estimated OC storage capacity, degraded steppe soils showed a high OC saturation of 78-85% despite massive SOC losses due to unsustainable land use. As a result, the potential of degraded grassland soils to sequester additional OC was generally low. This can be related to a relatively high contribution of labile SOC, which is preferentially lost in the course of soil degradation. Moreover, wind erosion leads to substantial loss of silt and clay particles and consequently results in a direct loss of the ability to stabilize additional OC. Our findings indicate that the SOC loss in semi-arid environments induced by intensive land use is largely irreversible. Observed SOC increases after improved land management mainly result in an accumulation of labile SOC prone to land use/climate changes and therefore cannot be regarded as contribution to long-term OC sequestration. © 2015 John Wiley & Sons Ltd.

A mathematical model of O2 transport in the rat outer medulla. II. Impact of outer medullary architecture.

PubMed

Chen, Jing; Edwards, Aurélie; Layton, Anita T

2009-08-01

we extended the region-based mathematical model of the urine-concentrating mechanism in the rat outer medulla (OM) developed by Layton and Layton (Am J Physiol Renal Physiol 289: F1346-F1366, 2005) to examine the impact of the complex structural organization of the OM on O(2) transport and distribution. In the present study, we investigated the sensitivity of predicted Po(2) profiles to several parameters that characterize the degree of OM regionalization, boundary conditions, structural dimensions, transmural transport properties, and relative positions and distributions of tubules and vessels. Our results suggest that the fraction of O(2) supplied to descending vasa recta (DVR) that reaches the inner medulla, i.e., a measure of the axial Po(2) gradient in the OM, is insensitive to parameter variations as a result of the sequestration of long DVR in the vascular bundles. In contrast, O(2) distribution among the regions surrounding the vascular core strongly depends on the radial positions of medullary thick ascending limbs (mTALs) relative to the vascular core, the degree of regionalization, and the distribution of short DVR along the corticomedullary axis. Moreover, if it is assumed that the mTAL active Na(+) transport rate decreases when mTAL Po(2) falls below a critical level, O(2) availability to mTALs has a significant impact on the concentrating capability of the model OM. The model also predicts that when the OM undergoes hypertrophy, its concentrating capability increases significantly only when anaerobic metabolism supports a substantial fraction of the mTAL active Na(+) transport and is otherwise critically reduced by low interstitial and mTAL luminal Po(2) in a hypertrophied OM.

Different designs of kinase-phosphatase interactions and phosphatase sequestration shapes the robustness and signal flow in the MAPK cascade

PubMed Central

2012-01-01

Background The three layer mitogen activated protein kinase (MAPK) signaling cascade exhibits different designs of interactions between its kinases and phosphatases. While the sequential interactions between the three kinases of the cascade are tightly preserved, the phosphatases of the cascade, such as MKP3 and PP2A, exhibit relatively diverse interactions with their substrate kinases. Additionally, the kinases of the MAPK cascade can also sequester their phosphatases. Thus, each topologically distinct interaction design of kinases and phosphatases could exhibit unique signal processing characteristics, and the presence of phosphatase sequestration may lead to further fine tuning of the propagated signal. Results We have built four architecturally distinct types of models of the MAPK cascade, each model with identical kinase-kinase interactions but unique kinases-phosphatases interactions. Our simulations unravelled that MAPK cascade’s robustness to external perturbations is a function of nature of interaction between its kinases and phosphatases. The cascade’s output robustness was enhanced when phosphatases were sequestrated by their target kinases. We uncovered a novel implicit/hidden negative feedback loop from the phosphatase MKP3 to its upstream kinase Raf-1, in a cascade resembling the B cell MAPK cascade. Notably, strength of the feedback loop was reciprocal to the strength of phosphatases’ sequestration and stronger sequestration abolished the feedback loop completely. An experimental method to verify the presence of the feedback loop is also proposed. We further showed, when the models were activated by transient signal, memory (total time taken by the cascade output to reach its unstimulated level after removal of signal) of a cascade was determined by the specific designs of interaction among its kinases and phosphatases. Conclusions Differences in interaction designs among the kinases and phosphatases can differentially shape the robustness and signal response behaviour of the MAPK cascade and phosphatase sequestration dramatically enhances the robustness to perturbations in each of the cascade. An implicit negative feedback loop was uncovered from our analysis and we found that strength of the negative feedback loop is reciprocally related to the strength of phosphatase sequestration. Duration of output phosphorylation in response to a transient signal was also found to be determined by the individual cascade’s kinase-phosphatase interaction design. PMID:22748295

Living Shorelines: Coastal Resilience with a Blue Carbon Benefit

PubMed Central

Davis, Jenny L.; Currin, Carolyn A.; O’Brien, Colleen; Raffenburg, Craig; Davis, Amanda

2015-01-01

Living shorelines are a type of estuarine shoreline erosion control that incorporates native vegetation and preserves native habitats. Because they provide the ecosystem services associated with natural coastal wetlands while also increasing shoreline resilience, living shorelines are part of the natural and hybrid infrastructure approach to coastal resiliency. Marshes created as living shorelines are typically narrow (< 30 m) fringing marshes with sandy substrates that are well flushed by tides. These characteristics distinguish living shorelines from the larger meadow marshes in which most of the current knowledge about created marshes was developed. The value of living shorelines for providing both erosion control and habitat for estuarine organisms has been documented but their capacity for carbon sequestration has not. We measured carbon sequestration rates in living shorelines and sandy transplanted Spartina alterniflora marshes in the Newport River Estuary, North Carolina. The marshes sampled here range in age from 12 to 38 years and represent a continuum of soil development. Carbon sequestration rates ranged from 58 to 283 g C m-2 yr-1 and decreased with marsh age. The pattern of lower sequestration rates in older marshes is hypothesized to be the result of a relative enrichment of labile organic matter in younger sites and illustrates the importance of choosing mature marshes for determination of long-term carbon sequestration potential. The data presented here are within the range of published carbon sequestration rates for S. alterniflora marshes and suggest that wide-scale use of the living shoreline approach to shoreline management may come with a substantial carbon benefit. PMID:26569503

Living Shorelines: Coastal Resilience with a Blue Carbon Benefit.

PubMed

Davis, Jenny L; Currin, Carolyn A; O'Brien, Colleen; Raffenburg, Craig; Davis, Amanda

2015-01-01

Living shorelines are a type of estuarine shoreline erosion control that incorporates native vegetation and preserves native habitats. Because they provide the ecosystem services associated with natural coastal wetlands while also increasing shoreline resilience, living shorelines are part of the natural and hybrid infrastructure approach to coastal resiliency. Marshes created as living shorelines are typically narrow (< 30 m) fringing marshes with sandy substrates that are well flushed by tides. These characteristics distinguish living shorelines from the larger meadow marshes in which most of the current knowledge about created marshes was developed. The value of living shorelines for providing both erosion control and habitat for estuarine organisms has been documented but their capacity for carbon sequestration has not. We measured carbon sequestration rates in living shorelines and sandy transplanted Spartina alterniflora marshes in the Newport River Estuary, North Carolina. The marshes sampled here range in age from 12 to 38 years and represent a continuum of soil development. Carbon sequestration rates ranged from 58 to 283 g C m-2 yr-1 and decreased with marsh age. The pattern of lower sequestration rates in older marshes is hypothesized to be the result of a relative enrichment of labile organic matter in younger sites and illustrates the importance of choosing mature marshes for determination of long-term carbon sequestration potential. The data presented here are within the range of published carbon sequestration rates for S. alterniflora marshes and suggest that wide-scale use of the living shoreline approach to shoreline management may come with a substantial carbon benefit.

Incidental Finding of Bronchopulmonary Sequestration in a 64-Year-Old Female.

PubMed

Tunsupon, Pichapong; Arshad, Ayesha; Patel, Sumit; Mador, M Jeffery

2017-01-01

Bronchopulmonary sequestration is a congenital abnormality of the primitive foregut. In adults, the typical age at presentation is 20-25 years. A 64-year-old female was referred for evaluation of an 8 × 6-cm right lower lobe cystic lesion. Her medical history was significant for recurrent right lower lobe pneumonia requiring multiple hospitalizations. Her physical examination was significant for crackles at the right lung base. Computed tomography (CT) of the chest with contrast showed cystic changes with thickened septation of the medial segment of the right lower lobe lacking distinct visceral pleura and with arterial supply from the anomalous branch of the thoracic aorta arising near the celiac trunk. Pulmonary angiography confirmed the diagnosis of intralobar pulmonary sequestration. The patient underwent celiac endovascular coil embolization of the anomalous artery to lessen the risk of hemorrhage prior to video-assisted thoracoscopic surgery (VATS) resection of the right lower lobe. She recovered well and was discharged home 1 week after VATS lobectomy. Follow-up CT of the chest 2 months later showed normal postsurgical changes related to right lower lobe lobectomy. The patient remained asymptomatic and resumed her daily activities. Pulmonary sequestration can present with recurrent pneumonia in late adulthood. Physicians must review any previous imaging studies of the chest to identify the structural abnormality and be cognizant of differential diagnoses such as infected cystic bronchiectasis, bronchogenic cyst, congenital diaphragmatic hernia, or cystic adenomatoid malformation that can occur in conjunction with bronchopulmonary sequestration. Pulmonary angiogram is the gold standard to confirm the diagnosis of bronchopulmonary sequestration. Surgical resection is the standard of care.

Integrating science, economics and law into policy: The case of carbon sequestration in climate change policy

NASA Astrophysics Data System (ADS)

Richards, Kenneth

Carbon sequestration, the extraction and storage of carbon from the atmosphere by biomass, could potentially provide a cost-effective means to reduce net greenhouse gas emissions. The claims on behalf of carbon sequestration may be inadvertently overstated, however. Several key observations emerge from this study. First, although carbon sequestration studies all report results in terms of dollars per ton, the definition of that term varies significantly, meaning that the results of various analyses can not be meaningfully compared. Second, when carbon sequestration is included in an energy-economy model of climate change policy, it appears that carbon sequestration could play a major, if not dominant role in a national carbon emission abatement program, reducing costs of emissions stabilization by as much as 80 percent, saving tens of billions of dollars per year. However, the results are very dependant upon landowners' perceived risk. Studies may also have overstated the potential for carbon sequestration because they have not considered the implementation process. This study demonstrates that three factors will reduce the cost-effectiveness of carbon sequestration. First, the implementation costs associated with measurement and governance of the government-private sector relation are higher than in the case of carbon source control. Second, legal constraints limit the range of instruments that the government can use to induce private landowners to expand their carbon sinks. The government will likely have to pay private parties to expand their sinks, or undertake direct government production. In either case, additional revenues will be required, introducing social costs associated with excess burden. Third, because of the very long time involved in developing carbon sinks (up to several decades) the government may not be able to make credible commitments against exactions of one type or another that would effectively reduce the value of private sector investments in carbon sinks. Consequently, the private sector will increase the rate of return required for participation, increasing the cost of this option. Carbon sequestration can still be a major factor in a national carbon emission abatement program. However, because of the interplay of science, economics and law, the most commonly prescribed environmental policy instruments--marketable allowance and taxes--have little or no direct role to play in the implementation process.

Development of Improved Caprock Integrity and Risk Assessment Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bruno, Michael

GeoMechanics Technologies has completed a geomechanical caprock integrity analysis and risk assessment study funded through the US Department of Energy. The project included: a detailed review of historical caprock integrity problems experienced in the natural gas storage industry; a theoretical description and documentation of caprock integrity issues; advanced coupled transport flow modelling and geomechanical simulation of three large-scale potential geologic sequestration sites to estimate geomechanical effects from CO₂ injection; development of a quantitative risk and decision analysis tool to assess caprock integrity risks; and, ultimately the development of recommendations and guidelines for caprock characterization and CO₂ injection operating practices. Historicalmore » data from gas storage operations and CO₂ sequestration projects suggest that leakage and containment incident risks are on the order of 10-1 to 10-2, which is higher risk than some previous studies have suggested for CO₂. Geomechanical analysis, as described herein, can be applied to quantify risks and to provide operating guidelines to reduce risks. The risk assessment tool developed for this project has been applied to five areas: The Wilmington Graben offshore Southern California, Kevin Dome in Montana, the Louden Field in Illinois, the Sleipner CO₂ sequestration operation in the North Sea, and the In Salah CO₂ sequestration operation in North Africa. Of these five, the Wilmington Graben area represents the highest relative risk while the Kevin Dome area represents the lowest relative risk.« less

Azolla along a phosphorus gradient: biphasic growth response linked to diazotroph traits and phosphorus-induced iron chlorosis.

PubMed

Temmink, Ralph J M; Harpenslager, Sarah F; Smolders, Alfons J P; van Dijk, Gijs; Peters, Roy C J H; Lamers, Leon P M; van Kempen, Monique M L

2018-03-13

Azolla spp., a water fern often used for phytoremediation, is a strong phosphorus (P) accumulator due to its high growth rate and N 2 fixing symbionts (diazotrophs). It is known that plant growth is stimulated by P, but the nature of the interactive response of both symbionts along a P gradient, and related changes in growth-limiting factors, are unclear. We determined growth, and N and P sequestration rates of Azolla filiculoides in N-free water at different P concentrations. The growth response appeared to be biphasic and highest at levels ≥10 P µmol l -1 . Diazotrophic N sequestration increased upon P addition, and rates were three times higher at high P than at low P. At 10 µmol P l -1 , N sequestration rates reached its maximum and A. filiculoides growth became saturated. Due to luxury consumption, P sequestration rates increased until 50 µmol P l -1 . At higher P concentrations (≥50 µmol l -1 ), however, chlorosis occurred that seems to be caused by iron- (Fe-), and not by N-deficiency. We demonstrate that traits of the complete symbiosis in relation to P and Fe availability determine plant performance, stressing the role of nutrient stoichiometry. The results are discussed regarding Azolla's potential use in a bio-based economy.

The role of reforestation in carbon sequestration

NASA Astrophysics Data System (ADS)

Nave, L. E.; Walters, B. F.; Hofmeister, K.; Perry, C. H.; Mishra, U.; Domke, G. M.; Swanston, C.

2017-12-01

In the United States (U.S.), the maintenance of forest cover is a legal mandate for federally managed forest lands. Reforestation is one option for maintaining forest cover on managed or disturbed lands, and as a land use change can increase forest cover on previously non-forested lands, enhancing carbon (C)-based ecosystem services and functions such as the production of woody biomass for forest products and the mitigation of atmospheric CO2 pollution and climate change. Nonetheless, multiple assessments indicate that reforestation in the U.S. lags behind its potential, with continued ecosystem services and functions at risk if reforestation is not increased. In this context, there is need for multiple independent analyses that quantify the role of reforestation in C sequestration. Here, we report the findings of a large-scale data synthesis aimed at four objectives: 1) estimate C storage in major pools in forest and other land cover types; 2) quantify sources of variation in C pools; 3) compare the impacts of reforestation and afforestation on C pools; 4) assess whether results hold or diverge across ecoregions. Our data-driven analysis provides four key inferences regarding reforestation and other land use impacts on C sequestration. First, soils are the dominant C pool under all land cover types in the U.S., and spatial variation in soil C pool sizes has less to do with land cover than with other factors. Second, where historically cultivated lands are being reforested, topsoils are sequestering significant amounts of C, with the majority of reforested lands yet to reach sequestration capacity (relative to forested baseline). Third, the establishment of woody vegetation delivers immediate to multi-decadal C sequestration benefits in biomass and coarse woody debris pools, with two- to three-fold C sequestration benefits during the first several decades following planting. Fourth, opportunities to enhance C sequestration through reforestation vary among ecoregions, according to current levels of planting, typical forest growth rates, and past land uses (especially cultivation). Altogether, our results suggest that an immediate, but phased and spatially targeted approach to reforestation can enhance C sequestration in forest biomass and soils in the U.S. for decades to centuries to come.

Translating National Level Forest Service Goals to Local Level Land Management: Carbon Sequestration

NASA Astrophysics Data System (ADS)

McNulty, S.; Treasure, E.

2017-12-01

The USDA Forest Service has many national level policies related to multiple use management. However, translating national policy to stand level forest management can be difficult. As an example of how a national policy can be put into action, we examined three case studies in which a desired future condition is evaluated at the national, region and local scale. We chose to use carbon sequestration as the desired future condition because climate change has become a major area of concern during the last decade. Several studies have determined that the 193 million acres of US national forest land currently sequester 11% to 15% of the total carbon emitted as a nation. This paper provides a framework by which national scale strategies for maintaining or enhancing forest carbon sequestration is translated through regional considerations and local constraints in adaptive management practices. Although this framework used the carbon sequestration as a case study, this framework could be used with other national level priorities such as the National Environmental Protection Act (NEPA) or the Endangered Species Act (ESA).

Relative contribution of maize and external manure amendment to soil carbon sequestration in a long-term intensive maize cropping system

PubMed Central

Zhang, Wenju; Liu, Kailou; Wang, Jinzhou; Shao, Xingfang; Xu, Minggang; Li, Jianwei; Wang, Xiujun; Murphy, Daniel V.

2015-01-01

We aimed to quantify the relative contributions of plant residue and organic manure to soil carbon sequestration. Using a 27-year-long inorganic fertilizer and manure amendment experiment in a maize (Zea mays L.) double-cropping system, we quantified changes in harvestable maize biomass and soil organic carbon stocks (0–20 cm depth) between 1986-2012. By employing natural 13C tracing techniques, we derived the proportional contributions of below-ground crop biomass return (maize-derived carbon) and external manure amendment (manure-derived carbon) to the total soil organic carbon stock. The average retention of maize-derived carbon plus manure-derived carbon during the early period of the trial (up to 11 years) was relatively high (10%) compared to the later period (22 to 27 years, 5.1–6.3%). About 11% of maize-derived carbon was converted to soil organic carbon, which was double the retention of manure-derived carbon (4.4–5.1%). This result emphasized that organic amendments were necessary to a win-win strategy for both SOC sequestration and maize production. PMID:26039186

Anthropogenic nitrogen deposition enhances carbon sequestration in boreal soils.

PubMed

Maaroufi, Nadia I; Nordin, Annika; Hasselquist, Niles J; Bach, Lisbet H; Palmqvist, Kristin; Gundale, Michael J

2015-08-01

It is proposed that carbon (C) sequestration in response to reactive nitrogen (Nr ) deposition in boreal forests accounts for a large portion of the terrestrial sink for anthropogenic CO2 emissions. While studies have helped clarify the magnitude by which Nr deposition enhances C sequestration by forest vegetation, there remains a paucity of long-term experimental studies evaluating how soil C pools respond. We conducted a long-term experiment, maintained since 1996, consisting of three N addition levels (0, 12.5, and 50 kg N ha(-1) yr(-1) ) in the boreal zone of northern Sweden to understand how atmospheric Nr deposition affects soil C accumulation, soil microbial communities, and soil respiration. We hypothesized that soil C sequestration will increase, and soil microbial biomass and soil respiration will decrease, with disproportionately large changes expected compared to low levels of N addition. Our data showed that the low N addition treatment caused a non-significant increase in the organic horizon C pool of ~15% and a significant increase of ~30% in response to the high N treatment relative to the control. The relationship between C sequestration and N addition in the organic horizon was linear, with a slope of 10 kg C kg(-1) N. We also found a concomitant decrease in total microbial and fungal biomasses and a ~11% reduction in soil respiration in response to the high N treatment. Our data complement previous data from the same study system describing aboveground C sequestration, indicating a total ecosystem sequestration rate of 26 kg C kg(-1) N. These estimates are far lower than suggested by some previous modeling studies, and thus will help improve and validate current modeling efforts aimed at separating the effect of multiple global change factors on the C balance of the boreal region. © 2015 John Wiley & Sons Ltd.

Roles of Raft-Anchored Adaptor Cbp/PAG1 in Spatial Regulation of c-Src Kinase

PubMed Central

Oneyama, Chitose; Suzuki, Takashi; Okada, Masato

2014-01-01

The tyrosine kinase c-Src is upregulated in numerous human cancers, implying a role for c-Src in cancer progression. Previously, we have shown that sequestration of activated c-Src into lipid rafts via a transmembrane adaptor, Cbp/PAG1, efficiently suppresses c-Src-induced cell transformation in Csk-deficient cells, suggesting that the transforming activity of c-Src is spatially regulated via Cbp in lipid rafts. To dissect the molecular mechanisms of the Cbp-mediated regulation of c-Src, a combined analysis was performed that included mathematical modeling and in vitro experiments in a c-Src- or Cbp-inducible system. c-Src activity was first determined as a function of c-Src or Cbp levels, using focal adhesion kinase (FAK) as a crucial c-Src substrate. Based on these experimental data, two mathematical models were constructed, the sequestration model and the ternary model. The computational analysis showed that both models supported our proposal that raft localization of Cbp is crucial for the suppression of c-Src function, but the ternary model, which includes a ternary complex consisting of Cbp, c-Src, and FAK, also predicted that c-Src function is dependent on the lipid-raft volume. Experimental analysis revealed that c-Src activity is elevated when lipid rafts are disrupted and the ternary complex forms in non-raft membranes, indicating that the ternary model accurately represents the system. Moreover, the ternary model predicted that, if Cbp enhances the interaction between c-Src and FAK, Cbp could promote c-Src function when lipid rafts are disrupted. These findings underscore the crucial role of lipid rafts in the Cbp-mediated negative regulation of c-Src-transforming activity, and explain the positive role of Cbp in c-Src regulation under particular conditions where lipid rafts are perturbed. PMID:24675741

Treatment for unstable pulmonary sequestration injury in patient with severe blunt trauma: A case report.

PubMed

Hiraki, Sakiko; Okada, Yohei; Arai, Yusuke; Ishii, Wataru; Iiduka, Ryoji

2017-08-01

Pulmonary sequestration is a congenital malformation characterized by nonfunctioning tissue not communicating with the tracheobronchial tree. As the blood pressure in the artery feeding the sequestrated lung tissue is higher than that in the normal pulmonary artery, the risk of massive hemorrhage in pulmonary sequestration is high. We herein present the first case of a severe blunt trauma patient with unstable pulmonary sequestration injury. The mechanism of pulmonary sequestration injury is vastly different than that of injury to normal lung. We suggest that proximal feeding artery embolization should be performed before surgical intervention in patients with massive hemorrhage of pulmonary sequestration due to severe chest trauma.

Lysosomes as mediators of drug resistance in cancer.

PubMed

Zhitomirsky, Benny; Assaraf, Yehuda G

2016-01-01

Drug resistance remains a leading cause of chemotherapeutic treatment failure and cancer-related mortality. While some mechanisms of anticancer drug resistance have been well characterized, multiple mechanisms remain elusive. In this respect, passive ion trapping-based lysosomal sequestration of multiple hydrophobic weak-base chemotherapeutic agents was found to reduce the accessibility of these drugs to their target sites, resulting in a markedly reduced cytotoxic effect and drug resistance. Recently we have demonstrated that lysosomal sequestration of hydrophobic weak base drugs triggers TFEB-mediated lysosomal biogenesis resulting in an enlarged lysosomal compartment, capable of enhanced drug sequestration. This study further showed that cancer cells with an increased number of drug-accumulating lysosomes are more resistant to lysosome-sequestered drugs, suggesting a model of drug-induced lysosome-mediated chemoresistance. In addition to passive drug sequestration of hydrophobic weak base chemotherapeutics, other mechanisms of lysosome-mediated drug resistance have also been reported; these include active lysosomal drug sequestration mediated by ATP-driven transporters from the ABC superfamily, and a role for lysosomal copper transporters in cancer resistance to platinum-based chemotherapeutics. Furthermore, lysosomal exocytosis was suggested as a mechanism to facilitate the clearance of chemotherapeutics which highly accumulated in lysosomes, thus providing an additional line of resistance, supplementing the organelle entrapment of chemotherapeutics away from their target sites. Along with these mechanisms of lysosome-mediated drug resistance, several approaches were recently developed for the overcoming of drug resistance or exploiting lysosomal drug sequestration, including lysosomal photodestruction and drug-induced lysosomal membrane permeabilization. In this review we explore the current literature addressing the role of lysosomes in mediating cancer drug resistance as well as novel modalities to overcome this chemoresistance. Copyright © 2015 Elsevier Ltd. All rights reserved.

[Characteristics of carbon storage of Inner Mongolia forests: a review].

PubMed

Yang, Hao; Hu, Zhong-Min; Zhang, Lei-Ming; Li, Sheng-Gong

2014-11-01

Forests in Inner Mongolia account for an important part of the forests in China in terms of their large area and high living standing volume. This study reported carbon storage, carbon density, carbon sequestration rate and carbon sequestration potential of forest ecosystems in Inner Mongolia using the biomass carbon data from the related literature. Through analyzing the data of forest inventory and the generalized allometric equations between volume and biomass, previous studies had reported that biomass carbon storage of the forests in Inner Mongolia was about 920 Tg C, which was 12 percent of the national forest carbon storage, the annual average growth rate was about 1.4%, and the average of carbon density was about 43 t · hm(-2). Carbon storage and carbon density showed an increasing trend over time. Coniferous and broad-leaved mixed forest, Pinus sylvestris var. mongolica forest and Betula platyphylla forest had higher carbon sequestration capacities. Carbon storage was reduced due to human activities such as thinning and clear cutting. There were few studies on carbon storage of the forests in Inner Mongolia with focus on the soil, showing that the soil car- bon density increased with the stand age. Study on the carbon sequestration potential of forest ecosystems was still less. Further study was required to examine dynamics of carbon storage in forest ecosystems in Inner Mongolia, i. e., to assess carbon storage in the forest soils together with biomass carbon storage, to compute biomass carbon content of species organs as 45% in the allometric equations, to build more species-specific and site-specific allometric equations including root biomass for different dominant species, and to take into account the effects of climate change on carbon sequestration rate and carbon sequestration potential.

Activated Neutrophils Are Associated with Pediatric Cerebral Malaria Vasculopathy in Malawian Children

PubMed Central

Feintuch, Catherine Manix; Saidi, Alex; Seydel, Karl; Chen, Grace; Goldman-Yassen, Adam; Mita-Mendoza, Neida K.; Kim, Ryung S.; Frenette, Paul S.; Taylor, Terrie

2016-01-01

ABSTRACT Most patients with cerebral malaria (CM) sustain cerebral microvascular sequestration of Plasmodium falciparum-infected red blood cells (iRBCs). Although many young children are infected with P. falciparum, CM remains a rare outcome; thus, we hypothesized that specific host conditions facilitate iRBC cerebral sequestration. To identify these host factors, we compared the peripheral whole-blood transcriptomes of Malawian children with iRBC cerebral sequestration, identified as malarial-retinopathy-positive CM (Ret+CM), to the transcriptomes of children with CM and no cerebral iRBC sequestration, defined as malarial-retinopathy-negative CM (Ret-CM). Ret+CM was associated with upregulation of 103 gene set pathways, including cytokine, blood coagulation, and extracellular matrix (ECM) pathways (P < 0.01; false-discovery rate [FDR] of <0.05). Neutrophil transcripts were the most highly upregulated individual transcripts in Ret+CM patients. Activated neutrophils can modulate diverse host processes, including the ECM, inflammation, and platelet biology to potentially facilitate parasite sequestration. Therefore, we compared plasma neutrophil proteins and neutrophil chemotaxis between Ret+CM and Ret-CM patients. Plasma levels of human neutrophil elastase, myeloperoxidase, and proteinase 3, but not lactoferrin or lipocalin, were elevated in Ret+CM patients, and neutrophil chemotaxis was impaired, possibly related to increased plasma heme. Neutrophils were rarely seen in CM brain microvasculature autopsy samples, and no neutrophil extracellular traps were found, suggesting that a putative neutrophil effect on endothelial cell biology results from neutrophil soluble factors rather than direct neutrophil cellular tissue effects. Meanwhile, children with Ret-CM had lower levels of inflammation, higher levels of alpha interferon, and upregulation of Toll-like receptor pathways and other host transcriptional pathways, which may represent responses that do not favor cerebral iRBC sequestration. PMID:26884431

Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes.

PubMed

Hilton, Benjamin A; Liu, Ji; Cartwright, Brian M; Liu, Yiyong; Breitman, Maya; Wang, Youjie; Jones, Rowdy; Tang, Hui; Rusinol, Antonio; Musich, Phillip R; Zou, Yue

2017-09-01

Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder that is caused by a point mutation in the LMNA gene, resulting in production of a truncated farnesylated-prelamin A protein (progerin). We previously reported that XPA mislocalized to the progerin-induced DNA double-strand break (DSB) sites, blocking DSB repair, which led to DSB accumulation, DNA damage responses, and early replication arrest in HGPS. In this study, the XPA mislocalization to DSBs occurred at stalled or collapsed replication forks, concurrent with a significant loss of PCNA at the forks, whereas PCNA efficiently bound to progerin. This PCNA sequestration likely exposed ds-ssDNA junctions at replication forks for XPA binding. Depletion of XPA or progerin each significantly restored PCNA at replication forks. Our results suggest that although PCNA is much more competitive than XPA in binding replication forks, PCNA sequestration by progerin may shift the equilibrium to favor XPA binding. Furthermore, we demonstrated that progerin-induced apoptosis could be rescued by XPA, suggesting that XPA-replication fork binding may prevent apoptosis in HGPS cells. Our results propose a mechanism for progerin-induced genome instability and accelerated replicative senescence in HGPS.-Hilton, B. A., Liu, J., Cartwright, B. M., Liu, Y., Breitman, M., Wang, Y., Jones, R., Tang, H., Rusinol, A., Musich, P. R., Zou, Y. Progerin sequestration of PCNA promotes replication fork collapse and mislocalization of XPA in laminopathy-related progeroid syndromes. © FASEB.

Orientation Effects in Fault Reactivation in Geological CO2 Sequestration

NASA Astrophysics Data System (ADS)

Castelletto, N.; Ferronato, M.; Gambolati, G.; Janna, C.; Teatini, P.

2012-12-01

Geological CO2 sequestration remains one of the most promising option for reducing the greenhouse gases emission. The accurate simulation of the complex coupled physical processes occurring during the injection and the post-injection stage represents a key issue for investigating the feasibility and the safety of the sequestration. The fluid-dynamical and geochemical aspects related to sequestering CO2 underground have been widely debated in the scientific literature over more than one decade. Recently, the importance of geomechanical processes has been widely recognized. In the present modeling study, we focus on fault reactivation induced by injection, an essential aspect for the evaluation of CO2 sequestration projects that needs to be adequately investigated to avoid the generation of preferential leaking path for CO2 and the related risk of induced seismicity. We use a geomechanical model based on the structural equations of poroelasticity solved by the Finite Element (FE) - Interface Element (IE) approach. Standard FEs are used to represent a continuum, while IEs prove especially suited to assess the relative displacements of adjacent elements such as the opening and slippage of existing faults or the generation of new fractures [1]. The IEs allow for the modeling of fault mechanics using an elasto-plastic constitutive law based on the Mohr-Coulomb failure criterion. We analyze the reactivation of a single fault in a synthetic reservoir by varying the fault orientation and size, hydraulic conductivity of the faulted zone, initial vertical and horizontal stress state and Mohr-Coulomb parameters (i.e., friction angle and cohesion). References: [1] Ferronato, M., G. Gambolati, C. Janna, and P. Teatini (2008), Numerical modeling of regional faults in land subsidence prediction above gas/oil reservoirs, Int. J. Numer. Anal. Methods Geomech., 32, 633-657.

Carbon sequestration pilot program : estimated land available for carbon sequestration in the national highway system

DOT National Transportation Integrated Search

2010-05-01

The Federal Highway Administration (FHWA) established the Carbon Sequestration Pilot Program (CSPP) in 2008 to assess whether a roadside carbon sequestration effort through modified maintenance and management practices is appropriate and feasible for...

Probabilistic evaluation of shallow groundwater resources at a hypothetical carbon sequestration site

DOE PAGES

Dai, Zhenxue; Keating, Elizabeth; Bacon, Diana H.; ...

2014-03-07

Carbon sequestration in geologic reservoirs is an important approach for mitigating greenhouse gases emissions to the atmosphere. This study first develops an integrated Monte Carlo method for simulating CO 2 and brine leakage from carbon sequestration and subsequent geochemical interactions in shallow aquifers. Then, we estimate probability distributions of five risk proxies related to the likelihood and volume of changes in pH, total dissolved solids, and trace concentrations of lead, arsenic, and cadmium for two possible consequence thresholds. The results indicate that shallow groundwater resources may degrade locally around leakage points by reduced pH and increased total dissolved solids (TDS).more » The volumes of pH and TDS plumes are most sensitive to aquifer porosity, permeability, and CO 2 and brine leakage rates. The estimated plume size of pH change is the largest, while that of cadmium is the smallest among the risk proxies. Plume volume distributions of arsenic and lead are similar to those of TDS. The scientific results from this study provide substantial insight for understanding risks of deep fluids leaking into shallow aquifers, determining the area of review, and designing monitoring networks at carbon sequestration sites.« less

Phytochrome B Requires PIF Degradation and Sequestration to Induce Light Responses Across a Wide Range of Light Conditions.

PubMed

Park, Eunae; Kim, Yeojae; Choi, Giltsu

2018-05-15

Phytochrome B (phyB) inhibits the function of phytochrome-interacting factors (PIFs) by inducing their degradation and sequestration, but the relative physiological importance of these two phyB activities is unclear. In an analysis of published Arabidopsis thaliana phyB mutations, we identified a point mutation in the N-terminal half of phyB (phyBG111D) that abolishes its PIF sequestration activity without affecting its PIF degradation activity. We also identified a point mutation in the phyB C-terminal domain, which, when combined with a deletion of the C-terminal end (phyB990G767R), does the opposite; it blocks PIF degradation without affecting PIF sequestration. The resulting phyB proteins, phyB990G767R and phyBG111D, are equally capable of inducing light responses under continuous red light. However, phyBG111D, which exhibits only the PIF degradation activity, induces stronger light responses than phyB990G767R under white light with prolonged dark periods (i.e., diurnal cycles). In contrast, phyB990G767R, which exhibits only the PIF sequestration activity, induces stronger light responses in flickering light (a condition that mimics sunflecks). Together, our results indicate that both of these separable phyB activities are required for light responses in varying light conditions. © 2018 American Society of Plant Biologists. All rights reserved.

Prolonged Curvularia endophthalmitis due to organism sequestration.

PubMed

Rachitskaya, Aleksandra V; Reddy, Ashvini K; Miller, Darlene; Davis, Janet; Flynn, Harry W; Smiddy, William; Lara, Wilfredo; Lin, Selina; Dubovy, Sander; Albini, Thomas A

2014-09-01

Endophthalmitis caused by Curvularia is a rare condition seen after cataract surgery and trauma. The clinical course has not been described previously. To examine the clinical course of 6 postoperative and trauma-related cases of Curvularia endophthalmitis. Retrospective case series. We reviewed the archives of the microbiology laboratory of Bascom Palmer Eye Institute, a tertiary referral hospital, from January 1, 1980, through September 30, 2013, to identify cases of Curvularia endophthalmitis. Data collected included demographic information, the cause of endophthalmitis, presenting features, treatment course, the number of recurrences, the area of organism sequestration, and final visual outcome. Trauma and cataract surgery. Times from the inciting event to presentation of symptoms, diagnosis, and eradication; visual acuity; and identification of the area of sequestration. We identified 6 patients with Curvularia endophthalmitis, including 5 who underwent cataract surgery and 1 after trauma. The diagnosis was established rapidly in the trauma case. In the postoperative cases, the time from the surgery to first symptoms ranged from 2 to 5 months; from the surgery to correct diagnosis, 7 to 24 months; and from the surgery to eradication, 8 to 27 months. Despite aggressive antifungal therapy, eradication of the infection could be achieved only by identification and removal of the nidus of sequestration. The median follow-up was 29.5 months. In cases of endophthalmitis caused by Curvularia, the diagnosis and treatment are often delayed, especially in postoperative cases. The eradication of the organism requires identification and removal of the nidi of sequestration.

In-Situ MVA of CO 2 Sequestration Using Smart Field Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohaghegh, Shahab D.

2014-09-01

Capability of underground carbon dioxide storage to confine and sustain injected CO 2 for a long period of time is the main concern for geologic CO 2 sequestration. If a leakage from a geological CO 2 sequestration site occurs, it is crucial to find the approximate amount and the location of the leak, in a timely manner, in order to implement proper remediation activities. An overwhelming majority of research and development for storage site monitoring has been concentrated on atmospheric, surface or near surface monitoring of the sequestered CO 2 . This study aims to monitor themore » integrity of CO 2 storage at the reservoir level. This work proposes developing in-situ CO 2 Monitoring and Verification technology based on the implementation of Permanent Down-hole Gauges (PDG) or “Smart Wells” along with Artificial Intelligence and Data Mining (AI&DM). The technology attempts to identify the characteristics of the CO 2 leakage by de-convolving the pressure signals collected from Permanent Down-hole Gauges (PDG). Citronelle field, a saline aquifer reservoir, located in the U.S. was considered as the basis for this study. A reservoir simulation model for CO 2 sequestration in the Citronelle field was developed and history matched. PDGs were installed, and therefore were considered in the numerical model, at the injection well and an observation well. Upon completion of the history matching process, high frequency pressure data from PDGs were generated using the history matched numerical model using different CO 2 leakage scenarios. Since pressure signal behaviors were too complicated to de-convolute using any existing mathematical formulations, a Machine Learning-based technology was introduced for this purpose. An Intelligent Leakage Detection System (ILDS) was developed as the result of this effort using the machine learning and pattern recognition technologies. The ILDS is able to detect leakage characteristics in a short period of time (less than a day from its occurrence) demonstrating the capability of the system in quantifying leakage characteristics subject to complex rate behaviors. The performance of ILDS is examined under different conditions such as multiple well leakages, cap rock leakage, availability of an additional monitoring well, presence of pressure drift and noise in the pressure sensor and uncertainty in the reservoir model.« less

Response comment: Carbon sequestration on Mars

USGS Publications Warehouse

Edwards, Christopher; Ehlmann, Bethany L.

2016-01-01

Martian atmospheric pressure has important implications for the past and present habitability of the planet, including the timing and causes of environmental change. The ancient Martian surface is strewn with evidence for early water bound in minerals (e.g., Ehlmann and Edwards, 2014) and recorded in surface features such as large catastrophically created outflow channels (e.g., Carr, 1979), valley networks (Hynek et al., 2010; Irwin et al., 2005), and crater lakes (e.g., Fassett and Head, 2008). Using orbital spectral data sets coupled with geologic maps and a set of numerical spectral analysis models, Edwards and Ehlmann (2015) constrained the amount of atmospheric sequestration in early Martian rocks and found that the majority of this sequestration occurred prior to the formation of the early Hesperian/late Noachian valley networks (Fassett and Head, 2011; Hynek et al., 2010), thus implying the atmosphere was already thin by the time these surface-water-related features were formed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grigg, Reid; McPherson, Brian; Lee, Rober

The Southwest Regional Partnership on Carbon Sequestration (SWP) one of seven regional partnerships sponsored by the U.S. Department of Energy (USDOE) carried out five field pilot tests in its Phase II Carbon Sequestration Demonstration effort, to validate the most promising sequestration technologies and infrastructure concepts, including three geologic pilot tests and two terrestrial pilot programs. This field testing demonstrated the efficacy of proposed sequestration technologies to reduce or offset greenhouse gas emissions in the region. Risk mitigation, optimization of monitoring, verification, and accounting (MVA) protocols, and effective outreach and communication were additional critical goals of these field validation tests. Themore » program included geologic pilot tests located in Utah, New Mexico, Texas, and a region-wide terrestrial analysis. Each geologic sequestration test site was intended to include injection of a minimum of ~75,000 tons/year CO{sub 2}, with minimum injection duration of one year. These pilots represent medium- scale validation tests in sinks that host capacity for possible larger-scale sequestration operations in the future. These validation tests also demonstrated a broad variety of carbon sink targets and multiple value-added benefits, including testing of enhanced oil recovery and sequestration, enhanced coalbed methane production and a geologic sequestration test combined with a local terrestrial sequestration pilot. A regional terrestrial sequestration demonstration was also carried out, with a focus on improved terrestrial MVA methods and reporting approaches specific for the Southwest region.« less

Evaluating the Contribution of Soil Carbon to Global Climate Change Mitigation in an Integrated Assessment

NASA Astrophysics Data System (ADS)

Thomson, A. M.; Izaurralde, R. C.; Clarke, L. E.

2006-12-01

Assessing the contribution of terrestrial carbon sequestration to national and international climate change mitigation requires integration across scientific and disciplinary boundaries. In a study for the US Climate Change Technology Program, site based measurements and geographic data were used to develop a three- pool, first-order kinetic model of global agricultural soil carbon (C) stock changes over 14 continental scale regions. This model was then used together with land use scenarios from the MiniCAM integrated assessment model in a global analysis of climate change mitigation options. MiniCAM evaluated mitigation strategies within a set of policy environments aimed at achieving atmospheric CO2 stabilization by 2100 under a suite of technology and development scenarios. Adoption of terrestrial sequestration practices is based on competition for land and economic markets for carbon. In the reference case with no climate policy, conversion of agricultural land from conventional cultivation to no tillage over the next century in the United States results in C sequestration of 7.6 to 59.8 Tg C yr-1, which doubles to 19.0 to 143.4 Tg C yr-1 under the most aggressive climate policy. Globally, with no carbon policy, agricultural C sequestration rates range from 75.2 to 18.2 Tg C yr-1 over the century, with the highest rates occurring in the first fifty years. Under the most aggressive global climate change policy, sequestration in agricultural soils reaches up to 190 Tg C yr-1 in the first 15 years. The contribution of agricultural soil C sequestration is a small fraction of the total global carbon offsets necessary to reach the stabilization targets (9 to 20 Gt C yr-1) by the end of the century. This integrated assessment provides decision makers with science-based estimates of the potential magnitude of terrestrial C sequestration relative to other greenhouse gas mitigation strategies in all sectors of the global economy. It also provides insight into the behavior of terrestrial C mitigation options in the presence and absence of climate change mitigation policies.

78 FR 10003 - Proposed Collection; Comment Request for Notice 2009-XX (NOT-151370-08)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-12

... comments concerning Notice 2009-XX, Credit for Carbon Dioxide Sequestration under Section 45Q. [email protected] . SUPPLEMENTARY INFORMATION: Title: Credit for Carbon Dioxide Sequestration under Section... carbon dioxide sequestration (CO 2 sequestration credit) under Sec. 45Q of the Internal Revenue Code...

Carbon dioxide adsorption in Brazilian coals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jose Luciano Soares; Andre L.B. Oberziner; Humberto J. Jose

Carbon dioxide (CO{sub 2}) is one of the most important greenhouse gases. In the period between 1980 and 1998, CO{sub 2} emissions increased more than 21% and projections suggest that the emissions will continue to increase globally by 2.2% between 2000 and 2020 and 3.3% in the developed countries. The sequestration of CO{sub 2} in deep unminable coal beds is one of the more promising of several methods of geological sequestration that are currently being investigated. CO{sub 2} can adsorb onto coal, and there are several studies demonstrating that CO{sub 2} dissolves in coals and swells them. At very lowmore » pressures (P {lt} 1 bar), CO{sub 2} dissolution does not seem to be a problem; however, high pressures are necessary for CO{sub 2} sequestration (P {gt} 50 bar). In this study, we evaluated the kinetics and equilibrium of sorption of CO{sub 2} on Brazilian coals at low pressures. The adsorption equilibrium isotherm at room temperature (30{sup o}C) was measured through the static method. The results showed that the Freundlich model or the Langmuir model is suitable to describe the equilibrium experimental results. The CO{sub 2} adsorption capacity of Brazilian coals are in the range of 0.089-0.186 mmol CO{sub 2}/g, which are typical values for coals with high ash content. The dynamics of adsorption in a fixed-bed column that contains granular coal (particle sizes of 0.8, 2.4, and 4.8 mm) showed that the adsorption rate is fast and a mathematical model was developed to describe the CO{sub 2} dynamics of the adsorption in a fixed-bed column. The linear driving force (LDF) was used to describe the rate of adsorption and the mass-transfer constants of the LDF model (K{sub s}) are in the range of 1.0-2.0 min{sup -1}. 29 refs., 5 figs., 3 tabs.« less

Multimodel predictive system for carbon dioxide solubility in saline formation waters.

PubMed

Wang, Zan; Small, Mitchell J; Karamalidis, Athanasios K

2013-02-05

The prediction of carbon dioxide solubility in brine at conditions relevant to carbon sequestration (i.e., high temperature, pressure, and salt concentration (T-P-X)) is crucial when this technology is applied. Eleven mathematical models for predicting CO(2) solubility in brine are compared and considered for inclusion in a multimodel predictive system. Model goodness of fit is evaluated over the temperature range 304-433 K, pressure range 74-500 bar, and salt concentration range 0-7 m (NaCl equivalent), using 173 published CO(2) solubility measurements, particularly selected for those conditions. The performance of each model is assessed using various statistical methods, including the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Different models emerge as best fits for different subranges of the input conditions. A classification tree is generated using machine learning methods to predict the best-performing model under different T-P-X subranges, allowing development of a multimodel predictive system (MMoPS) that selects and applies the model expected to yield the most accurate CO(2) solubility prediction. Statistical analysis of the MMoPS predictions, including a stratified 5-fold cross validation, shows that MMoPS outperforms each individual model and increases the overall accuracy of CO(2) solubility prediction across the range of T-P-X conditions likely to be encountered in carbon sequestration applications.

Status and potential of terrestrial carbon sequestration in West Virginia

Treesearch

Benktesh D. Sharma; Jingxin Wang

2011-01-01

Terrestrial ecosystem management offers cost-effective ways to enhance carbon (C) sequestration. This study utilized C stock and C sequestration in forest and agricultural lands, abandoned mine lands, and harvested wood products to estimate the net current annual C sequestration in West Virginia. Several management options within these components were simulated using a...

Use of relational databases to evaluate regional petroleum accumulation, groundwater flow, and CO2 sequestration in Kansas

USGS Publications Warehouse

Carr, T.R.; Merriam, D.F.; Bartley, J.D.

2005-01-01

Large-scale relational databases and geographic information system tools are used to integrate temperature, pressure, and water geo-chemistry data from numerous wells to better understand regional-scale geothermal and hydrogeological regimes of the lower Paleozoic aquifer systems in the mid-continent and to evaluate their potential for geologic CO2 sequestration. The lower Paleozoic (Cambrian to Mississippian) aquifer systems in Kansas, Missouri, and Oklahoma comprise one of the largest regional-scale saline aquifer systems in North America. Understanding hydrologic conditions and processes of these regional-scale aquifer systems provides insight to the evolution of the various sedimentary basins, migration of hydrocarbons out of the Anadarko and Arkoma basins, and the distribution of Arbuckle petroleum reservoirs across Kansas and provides a basis to evaluate CO2 sequestration potential. The Cambrian and Ordovician stratigraphic units form a saline aquifer that is in hydrologic continuity with the freshwater recharge from the Ozark plateau and along the Nemaha anticline. The hydrologic continuity with areas of freshwater recharge provides an explanation for the apparent underpressure in the Arbuckle Group. Copyright ?? 2005. The American Association of Petroleum Geologists. All rights reserved.

Simulating carbon sequestration using cellular automata and land use assessment for Karaj, Iran

NASA Astrophysics Data System (ADS)

Khatibi, Ali; Pourebrahim, Sharareh; Mokhtar, Mazlin Bin

2018-06-01

Carbon sequestration has been proposed as a means of slowing the atmospheric and marine accumulation of greenhouse gases. This study used observed and simulated land use/cover changes to investigate and predict carbon sequestration rates in the city of Karaj. Karaj, a metropolis of Iran, has undergone rapid population expansion and associated changes in recent years, and these changes make it suitable for use as a case study for rapidly expanding urban areas. In particular, high quality agricultural space, green space and gardens have rapidly transformed into industrial, residential and urban service areas. Five classes of land use/cover (residential, agricultural, rangeland, forest and barren areas) were considered in the study; vegetation and soil samples were taken from 20 randomly selected locations. The level of carbon sequestration was determined for the vegetation samples by calculating the amount of organic carbon present using the dry plant weight method, and for soil samples by using the method of Walkley and Black. For each area class, average values of carbon sequestration in vegetation and soil samples were calculated to give a carbon sequestration index. A cellular automata approach was used to simulate changes in the classes. Finally, the carbon sequestration indices were combined with simulation results to calculate changes in carbon sequestration for each class. It is predicted that, in the 15 year period from 2014 to 2029, much agricultural land will be transformed into residential land, resulting in a severe reduction in the level of carbon sequestration. Results from this study indicate that expansion of forest areas in urban counties would be an effective means of increasing the levels of carbon sequestration. Finally, future opportunities to include carbon sequestration into the simulation of land use/cover changes are outlined.

Going With the Flow: An Aid in Detecting and Differentiating Bronchopulmonary Sequestrations and Hybrid Lesions.

PubMed

Oliver, Edward R; DeBari, Suzanne E; Giannone, Mariann M; Pogoriler, Jennifer E; Johnson, Ann M; Horii, Steven C; Gebb, Juliana S; Howell, Lori J; Adzick, N Scott; Coleman, Beverly G

2018-02-01

To assess the ability of prenatal ultrasound (US) in identifying systemic feeding arteries in bronchopulmonary sequestrations and hybrid lesions and report the ability of US in classifying bronchopulmonary sequestrations as intralobar or extralobar. Institutional Review Board-approved radiology and clinical database searches from 2008 to 2015 were performed for prenatal lung lesions with final diagnoses of bronchopulmonary sequestrations or hybrid lesions. All patients had detailed US examinations, and most patients had ultrafast magnetic resonance imaging (MRI). Lesion location, size, and identification of systemic feeding arteries and draining veins were assessed with US. The study consisted of 102 bronchopulmonary sequestrations and 86 hybrid lesions. The median maternal age was 30 years. The median gestational age was 22 weeks 5 days. Of bronchopulmonary sequestrations, 66 had surgical pathologic confirmation, and 100 had postnatal imaging. Bronchopulmonary sequestration locations were intrathoracic (n = 77), intra-abdominal (n = 19), and transdiaphragmatic (n = 6). Of hybrid lesions, 84 had surgical pathologic confirmation, and 83 had postnatal imaging. Hybrid lesion locations were intrathoracic (n = 84) and transdiaphragmatic (n = 2). Ultrasound correctly identified systemic feeding arteries in 86 of 102 bronchopulmonary sequestrations and 79 of 86 hybrid lesions. Of patients who underwent MRI, systemic feeding arteries were reported in 62 of 92 bronchopulmonary sequestrations and 56 of 81 hybrid lesions. Ultrasound identified more systemic feeding arteries than MRI in both bronchopulmonary sequestrations and hybrid lesions (P < .01). Magnetic resonance imaging identified systemic feeding arteries that US did not in only 2 cases. In cases in which both systemic feeding arteries and draining veins were identified, US could correctly predict intrathoracic lesions as intralobar or extralobar in 44 of 49 bronchopulmonary sequestrations and 68 of 73 hybrid lesions. Ultrasound is most accurate for systemic feeding artery detection in bronchopulmonary sequestrations and hybrid lesions and can also type the lesions as intralobar or extralobar when draining veins are evaluated. © 2017 by the American Institute of Ultrasound in Medicine.

Capturing spiral radial growth of conifers using the superellipse to model tree-ring geometric shape

PubMed Central

Shi, Pei-Jian; Huang, Jian-Guo; Hui, Cang; Grissino-Mayer, Henri D.; Tardif, Jacques C.; Zhai, Li-Hong; Wang, Fu-Sheng; Li, Bai-Lian

2015-01-01

Tree-rings are often assumed to approximate a circular shape when estimating forest productivity and carbon dynamics. However, tree rings are rarely, if ever, circular, thereby possibly resulting in under- or over-estimation in forest productivity and carbon sequestration. Given the crucial role played by tree ring data in assessing forest productivity and carbon storage within a context of global change, it is particularly important that mathematical models adequately render cross-sectional area increment derived from tree rings. We modeled the geometric shape of tree rings using the superellipse equation and checked its validation based on the theoretical simulation and six actual cross sections collected from three conifers. We found that the superellipse better describes the geometric shape of tree rings than the circle commonly used. We showed that a spiral growth trend exists on the radial section over time, which might be closely related to spiral grain along the longitudinal axis. The superellipse generally had higher accuracy than the circle in predicting the basal area increment, resulting in an improved estimate for the basal area. The superellipse may allow better assessing forest productivity and carbon storage in terrestrial forest ecosystems. PMID:26528316

Capturing spiral radial growth of conifers using the superellipse to model tree-ring geometric shape.

PubMed

Shi, Pei-Jian; Huang, Jian-Guo; Hui, Cang; Grissino-Mayer, Henri D; Tardif, Jacques C; Zhai, Li-Hong; Wang, Fu-Sheng; Li, Bai-Lian

2015-01-01

Tree-rings are often assumed to approximate a circular shape when estimating forest productivity and carbon dynamics. However, tree rings are rarely, if ever, circular, thereby possibly resulting in under- or over-estimation in forest productivity and carbon sequestration. Given the crucial role played by tree ring data in assessing forest productivity and carbon storage within a context of global change, it is particularly important that mathematical models adequately render cross-sectional area increment derived from tree rings. We modeled the geometric shape of tree rings using the superellipse equation and checked its validation based on the theoretical simulation and six actual cross sections collected from three conifers. We found that the superellipse better describes the geometric shape of tree rings than the circle commonly used. We showed that a spiral growth trend exists on the radial section over time, which might be closely related to spiral grain along the longitudinal axis. The superellipse generally had higher accuracy than the circle in predicting the basal area increment, resulting in an improved estimate for the basal area. The superellipse may allow better assessing forest productivity and carbon storage in terrestrial forest ecosystems.

100% Solids Polyurethane Sequestration Coating

DTIC Science & Technology

2014-04-11

Distribution Unlimited 100% Solids Polyurethane Sequestration Coating The views, opinions and/or findings contained in this report are those of the...Papers published in non peer-reviewed journals: 100% Solids Polyurethane Sequestration Coating Report Title Report developed under Topic #CBD13-101...Final Technical Report Contract #: W911NF-13-P-0010 Proposal #: 63958CHSB1 Project: 100% Solids Polyurethane Sequestration Coating

Reduced carbon sequestration potential of biochar in acidic soil.

PubMed

Sheng, Yaqi; Zhan, Yu; Zhu, Lizhong

2016-12-01

Biochar application in soil has been proposed as a promising method for carbon sequestration. While factors affecting its carbon sequestration potential have been widely investigated, the number of studies on the effect of soil pH is limited. To investigate the carbon sequestration potential of biochar across a series of soil pH levels, the total carbon emission, CO 2 release from inorganic carbon, and phospholipid fatty acids (PLFAs) of six soils with various pH levels were compared after the addition of straw biochar produced at different pyrolysis temperatures. The results show that the acidic soils released more CO 2 (1.5-3.5 times higher than the control) after the application of biochar compared with neutral and alkaline soils. The degradation of both native soil organic carbon (SOC) and biochar were accelerated. More inorganic CO 2 release in acidic soil contributed to the increased degradation of biochar. Higher proportion of gram-positive bacteria in acidic soil (25%-36%) was responsible for the enhanced biochar degradation and simultaneously co-metabolism of SOC. In addition, lower substrate limitation for bacteria, indicated by higher C-O stretching after the biochar application in the acidic soil, also caused more CO 2 release. In addition to the soil pH, other factors such as clay contents and experimental duration also affected the phsico-chemical and biotic processes of SOC dynamics. Gram-negative/gram-positive bacteria ratio was found to be negatively related to priming effects, and suggested to serve as an indicator for priming effect. In general, the carbon sequestration potential of rice-straw biochar in soil reduced along with the decrease of soil pH especially in a short-term. Given wide spread of acidic soils in China, carbon sequestration potential of biochar may be overestimated without taking into account the impact of soil pH. Copyright © 2016 Elsevier B.V. All rights reserved.

Long-term nitrogen regulation of forest carbon sequestration

NASA Astrophysics Data System (ADS)

Yang, Y.; Luo, Y.

2009-12-01

It is well established that nitrogen (N) limits plant production but unclear how N regulates long-term terrestrial carbon (C) sequestration in response to rising atmospheric C dioxide (CO2)(Luo et al., 2004). Most experimental evidence on C-N interactions is primarily derived from short-term CO2 manipulative studies (e.g. Oren et al., 2001; Reich et al., 2006a), which abruptly increase C inputs into ecosystems and N demand from soil while atmospheric CO2 concentration in the real world is gradually increasing over time (Luo & Reynolds, 1999). It is essential to examine long-term N regulations of C sequestration in natural ecosystems. Here we present results of a synthesis of more than 100 studies on long-term C-N interactions during secondary succession. C significantly accumulates in plant, litter and forest floor in most studies, and in mineral soil in one-third studies during stand development. Substantial increases in C stock are tightly coupled with N accretion. The C: N ratio in plant increases with stand age in most cases, but remains relatively constant in litter, forest floor and mineral soil. Our results suggest that natural ecosystems could have the intrinsic capacity to maintain long-term C sequestration through external N accrual, high N use efficiency, and efficient internal N cycling.

Spatially simulating changes of soil water content and their effects on carbon sequestration in Canada's forests and wetlands

NASA Astrophysics Data System (ADS)

Ju, Weimin; Chen, Jing M.; Black, T. Andrew; Barr, Alan G.; McCaughey, Harry

2010-07-01

The variations of soil water content (SWC) and its influences on the carbon (C) cycle in Canada's forests and wetlands were studied through model simulations using the Integrated Terrestrial Ecosystem Carbon (InTEC) model. It shows that Canada's forests and wetlands experienced spatially and temporally heterogeneous changes in SWC from 1901 to 2000. SWC changes caused average NPP to decrease 40.8 Tg C yr-1 from 1901 to 2000, whereas the integrated effect of non-disturbance factors (climate change, CO2 fertilization and N deposition) enhanced NPP by 9.9%. During 1981-2000, the reduction of NPP caused by changes in SWC was 58.1 Tg C yr-1 whereas non-disturbance factors together caused NPP to increase by 16.6%. SWC changes resulted in an average increase of 4.1 Tg C yr-1 in the net C uptake during 1901-2000, relatively small compared with the enhancement in C uptake of 50.2 Tg C yr-1 by the integrated effect of non-disturbance factors. During 1981-2000, changes in SWC caused a reduction of 3.8 Tg C yr-1 in net C sequestration whereas the integrated factors increased net C sequestration by 54.1 Tg C yr-1. Increase in SWC enhanced C sequestration in all ecozones.

Three-decade long fertilization-induced soil organic carbon sequestration depends on edaphic characteristics in six typical croplands

PubMed Central

Liang, Feng; Li, Jianwei; Yang, Xueyun; Huang, Shaomin; Cai, Zejiang; Gao, Hongjun; Ma, Junyong; Cui, Xian; Xu, Minggang

2016-01-01

Fertilizations affect soil organic carbon (SOC) content but the relative influences of the edaphic and climate factors on SOC storage are rarely studied across wide spatiotemporal scales. This study synthesized long-term datasets of fertilization experiments in six typical Chinese croplands, and calculated annual C input from crops and manure amendments, changes in SOC storage (ΔSOC) and C sequestration efficiency (i.e. the percentage of soil C change per unit of C input, hereafter referred as CSE) in 0–20 cm soil over three decades. Three fertilization treatments include no fertilization (CK), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and combined chemical fertilizers and manure (NPKM). Results showed significant fertilization effects on C input and ΔSOC (NPKM>NPK>CK), and significantly higher CSE in Qiyang at Hunan than Zhengzhou at Henan and Heihe at Heilongjiang. The variance partitioning analysis (VPA) showed more variance of CSE can be explained by edaphic factors (up to 39.7%) than other factors. Furthermore, soil available N content and pH were identified as the major soil properties explaining CSE variance. This study demonstrated key controls of soil fertility factors on SOC sequestration and informs the need to develop strategic soil management plan to promote soil carbon sequestration under long-term intensive fertilization. PMID:27492771

Three-decade long fertilization-induced soil organic carbon sequestration depends on edaphic characteristics in six typical croplands

NASA Astrophysics Data System (ADS)

Liang, Feng; Li, Jianwei; Yang, Xueyun; Huang, Shaomin; Cai, Zejiang; Gao, Hongjun; Ma, Junyong; Cui, Xian; Xu, Minggang

2016-08-01

Fertilizations affect soil organic carbon (SOC) content but the relative influences of the edaphic and climate factors on SOC storage are rarely studied across wide spatiotemporal scales. This study synthesized long-term datasets of fertilization experiments in six typical Chinese croplands, and calculated annual C input from crops and manure amendments, changes in SOC storage (ΔSOC) and C sequestration efficiency (i.e. the percentage of soil C change per unit of C input, hereafter referred as CSE) in 0-20 cm soil over three decades. Three fertilization treatments include no fertilization (CK), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and combined chemical fertilizers and manure (NPKM). Results showed significant fertilization effects on C input and ΔSOC (NPKM>NPK>CK), and significantly higher CSE in Qiyang at Hunan than Zhengzhou at Henan and Heihe at Heilongjiang. The variance partitioning analysis (VPA) showed more variance of CSE can be explained by edaphic factors (up to 39.7%) than other factors. Furthermore, soil available N content and pH were identified as the major soil properties explaining CSE variance. This study demonstrated key controls of soil fertility factors on SOC sequestration and informs the need to develop strategic soil management plan to promote soil carbon sequestration under long-term intensive fertilization.

Three-decade long fertilization-induced soil organic carbon sequestration depends on edaphic characteristics in six typical croplands.

PubMed

Liang, Feng; Li, Jianwei; Yang, Xueyun; Huang, Shaomin; Cai, Zejiang; Gao, Hongjun; Ma, Junyong; Cui, Xian; Xu, Minggang

2016-08-05

Fertilizations affect soil organic carbon (SOC) content but the relative influences of the edaphic and climate factors on SOC storage are rarely studied across wide spatiotemporal scales. This study synthesized long-term datasets of fertilization experiments in six typical Chinese croplands, and calculated annual C input from crops and manure amendments, changes in SOC storage (ΔSOC) and C sequestration efficiency (i.e. the percentage of soil C change per unit of C input, hereafter referred as CSE) in 0-20 cm soil over three decades. Three fertilization treatments include no fertilization (CK), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and combined chemical fertilizers and manure (NPKM). Results showed significant fertilization effects on C input and ΔSOC (NPKM>NPK>CK), and significantly higher CSE in Qiyang at Hunan than Zhengzhou at Henan and Heihe at Heilongjiang. The variance partitioning analysis (VPA) showed more variance of CSE can be explained by edaphic factors (up to 39.7%) than other factors. Furthermore, soil available N content and pH were identified as the major soil properties explaining CSE variance. This study demonstrated key controls of soil fertility factors on SOC sequestration and informs the need to develop strategic soil management plan to promote soil carbon sequestration under long-term intensive fertilization.

Simulating the Cranfield geological carbon sequestration project with high-resolution static models and an accurate equation of state

DOE PAGES

Soltanian, Mohamad Reza; Amooie, Mohammad Amin; Cole, David R.; ...

2016-10-11

In this study, a field-scale carbon dioxide (CO 2) injection pilot project was conducted as part of the Southeast Regional Sequestration Partnership (SECARB) at Cranfield, Mississippi. We present higher-order finite element simulations of the compositional two-phase CO 2-brine flow and transport during the experiment. High- resolution static models of the formation geology in the Detailed Area Study (DAS) located below the oil- water contact (brine saturated) are used to capture the impact of connected flow paths on breakthrough times in two observation wells. Phase behavior is described by the cubic-plus-association (CPA) equation of state, which takes into account the polarmore » nature of water molecules. Parameter studies are performed to investigate the importance of Fickian diffusion, permeability heterogeneity, relative permeabilities, and capillarity. Simulation results for the pressure response in the injection well and the CO 2 breakthrough times at the observation wells show good agreement with the field data. For the high injection rates and short duration of the experiment, diffusion is relatively unimportant (high P clet numbers), while relative permeabilities have a profound impact on the pressure response. High-permeability pathways, created by fluvial deposits, strongly affect the CO 2 transport and highlight the importance of properly characterizing the formation heterogeneity in future carbon sequestration projects.« less

The sequestration switch: removing industrial CO2 by direct ocean absorption.

PubMed

Ametistova, Lioudmila; Twidell, John; Briden, James

2002-04-22

This review paper considers direct injection of industrial CO2 emissions into the mid-water oceanic column below 500 m depth. Such a process is a potential candidate for switching atmospheric carbon emissions directly to long term sequestration, thereby relieving the intermediate atmospheric burden. Given sufficient research justification, the argument is that harmful impact in both the Atmosphere and the biologically rich upper marine layer could be reduced. The paper aims to estimate the role that active intervention, through direct ocean CO2 storage, could play and to outline further research and assessment for the strategy to be a viable option for climate change mitigation. The attractiveness of direct ocean injection lies in its bypassing of the Atmosphere and upper marine region, its relative permanence, its practicability using existing technologies and its quantification. The difficulties relate to the uncertainty of some fundamental scientific issues, such as plume dynamics, lowered pH of the exposed waters and associated ecological impact, the significant energy penalty associated with the necessary engineering plant and the uncertain costs. Moreover, there are considerable uncertainties regarding related international marine law. Development of the process would require acceptance of the evidence for climate change, strict requirements for large industrial consumers of fossil fuel to reduce CO2 emissions into the Atmosphere and scientific evidence for the overall beneficial impact of ocean sequestration.

Simple dielectric mixing model in the monitoring of CO2 leakage from geological storage aquifer

NASA Astrophysics Data System (ADS)

Abidoye, L. K.; Bello, A. A.

2017-03-01

The principle of the dielectric mixing for multiphase systems in porous media has been employed to investigate CO2-water-porous media system and monitor the leakage of CO2, in analogy to scenarios that can be encountered in geological carbon sequestration. A dielectric mixing model was used to relate the relative permittivity for different subsurface materials connected with the geological carbon sequestration. The model was used to assess CO2 leakage and its upward migration, under the influences of the depth-dependent characteristics of the subsurface media as well as the fault-connected aquifers. The results showed that for the upward migration of CO2 in the subsurface, the change in the bulk relative permittivity (εb) of the CO2-water-porous media system clearly depicts the leakage and movement of CO2, especially at depth shallower than 800 m. At higher depth, with higher pressure and temperature, the relative permittivity of CO2 increases with pressure, while that of water decreases with temperature. These characteristics of water and supercritical CO2, combine to limit the change in the εb, at higher depth. Furthermore, it was noted that if the pore water was not displaced by the migrating CO2, the presence of CO2 in the system increases the εb. But, with the displacement of pore water by the migrating CO2, it was shown how the εb profile decreases with time. Owing to its relative simplicity, composite dielectric behaviour of multiphase materials can be effectively deployed for monitoring and enhancement of control of CO2 movement in the geological carbon sequestration.

Regression of left ventricular dilation after percutaneous closure of a large intralobar pulmonary sequestration.

PubMed

Alvarez, Alejandro; Borgia, Francesco; Guccione, Paolo

2010-02-01

We describe an infant of 8 months who presented with left ventricular dilation due to an extensive intralobar sequestration of the right lung. The pulmonary sequestration was associated with a patent arterial duct and a right aortic arch. Percutaneous closure of the anomalous aberrant artery feeding the sequestrated lung resulted in prompt regression of the left ventricular enlargement.

Options for accounting carbon sequestration in German forests

PubMed Central

Krug, Joachim; Koehl, Michael; Riedel, Thomas; Bormann, Kristin; Rueter, Sebastian; Elsasser, Peter

2009-01-01

Background The Accra climate change talks held from 21–27 August 2008 in Accra, Ghana, were part of an ongoing series of meetings leading up to the Copenhagen meeting in December 2009. During the meeting a set of options for accounting carbon sequestration in forestry on a post-2012 framework was presented. The options include gross-net and net-net accounting and approaches for establishing baselines. Results This article demonstrates the embedded consequences of Accra Accounting Options for the case study of German national GHG accounting. It presents the most current assessment of sequestration rates by forest management for the period 1990 – 2007, provides an outlook of future emissions and removals (up to the year 2042) as related to three different management scenarios, and shows that implementation of some Accra options may reverse sources to sinks, or sinks to sources. Conclusion The results of the study highlight the importance of elaborating an accounting system that would prioritize the climate convention goals, not national preferences. PMID:19650896

Large-scale sequestration of atmospheric carbon via plant roots in natural and agricultural ecosystems: why and how.

PubMed

Kell, Douglas B

2012-06-05

The soil holds twice as much carbon as does the atmosphere, and most soil carbon is derived from recent photosynthesis that takes carbon into root structures and further into below-ground storage via exudates therefrom. Nonetheless, many natural and most agricultural crops have roots that extend only to about 1 m below ground. What determines the lifetime of below-ground C in various forms is not well understood, and understanding these processes is therefore key to optimising them for enhanced C sequestration. Most soils (and especially subsoils) are very far from being saturated with organic carbon, and calculations show that the amounts of C that might further be sequestered (http://dbkgroup.org/carbonsequestration/rootsystem.html) are actually very great. Breeding crops with desirable below-ground C sequestration traits, and exploiting attendant agronomic practices optimised for individual species in their relevant environments, are therefore important goals. These bring additional benefits related to improvements in soil structure and in the usage of other nutrients and water.

Na+/K+-ATPase resistance and cardenolide sequestration: basal adaptations to host plant toxins in the milkweed bugs (Hemiptera: Lygaeidae: Lygaeinae)

PubMed Central

Bramer, Christiane; Dobler, Susanne; Deckert, Jürgen; Stemmer, Michael; Petschenka, Georg

2015-01-01

Despite sequestration of toxins being a common coevolutionary response to plant defence in phytophagous insects, the macroevolution of the traits involved is largely unaddressed. Using a phylogenetic approach comprising species from four continents, we analysed the ability to sequester toxic cardenolides in the hemipteran subfamily Lygaeinae, which is widely associated with cardenolide-producing Apocynaceae. In addition, we analysed cardenolide resistance of their Na+/K+-ATPases, the molecular target of cardenolides. Our data indicate that cardenolide sequestration and cardenolide-resistant Na+/K+-ATPase are basal adaptations in the Lygaeinae. In two species that shifted to non-apocynaceous hosts, the ability to sequester was secondarily reduced, yet Na+/K+-ATPase resistance was maintained. We suggest that both traits evolved together and represent major coevolutionary adaptations responsible for the evolutionary success of lygaeine bugs. Moreover, specialization on cardenolides was not an evolutionary dead end, but enabled this insect lineage to host shift to cardenolide-producing plants from distantly related families. PMID:25808891

Options for accounting carbon sequestration in German forests.

PubMed

Krug, Joachim; Koehl, Michael; Riedel, Thomas; Bormann, Kristin; Rueter, Sebastian; Elsasser, Peter

2009-08-03

The Accra climate change talks held from 21-27 August 2008 in Accra, Ghana, were part of an ongoing series of meetings leading up to the Copenhagen meeting in December 2009. During the meeting a set of options for accounting carbon sequestration in forestry on a post-2012 framework was presented. The options include gross-net and net-net accounting and approaches for establishing baselines. This article demonstrates the embedded consequences of Accra Accounting Options for the case study of German national GHG accounting. It presents the most current assessment of sequestration rates by forest management for the period 1990 - 2007, provides an outlook of future emissions and removals (up to the year 2042) as related to three different management scenarios, and shows that implementation of some Accra options may reverse sources to sinks, or sinks to sources. The results of the study highlight the importance of elaborating an accounting system that would prioritize the climate convention goals, not national preferences.

Geophysical monitoring technology for CO2 sequestration

NASA Astrophysics Data System (ADS)

Ma, Jin-Feng; Li, Lin; Wang, Hao-Fan; Tan, Ming-You; Cui, Shi-Ling; Zhang, Yun-Yin; Qu, Zhi-Peng; Jia, Ling-Yun; Zhang, Shu-Hai

2016-06-01

Geophysical techniques play key roles in the measuring, monitoring, and verifying the safety of CO2 sequestration and in identifying the efficiency of CO2-enhanced oil recovery. Although geophysical monitoring techniques for CO2 sequestration have grown out of conventional oil and gas geophysical exploration techniques, it takes a long time to conduct geophysical monitoring, and there are many barriers and challenges. In this paper, with the initial objective of performing CO2 sequestration, we studied the geophysical tasks associated with evaluating geological storage sites and monitoring CO2 sequestration. Based on our review of the scope of geophysical monitoring techniques and our experience in domestic and international carbon capture and sequestration projects, we analyzed the inherent difficulties and our experiences in geophysical monitoring techniques, especially, with respect to 4D seismic acquisition, processing, and interpretation.

Study on the methodology of road carbon sink forest

NASA Astrophysics Data System (ADS)

Wan, Lijuan; Zhang, Yi; Cheng, Dongxiang; Huang, Yanan

2017-01-01

Advanced concepts of forest carbon sink and forestry carbon sequestration are introduced in road carbon sink forest project and the measurement and carbon monitoring of road carbon sink forest are explored. Experience and technology are accumulated and a set of the carbon sequestration forestation and carbon measurement and monitoring technology systems on both sides of road are formed. To update the green concept, improve the forestation quality along road and to enhanced sequestration and ecological efficiency, it is important to realize the traffic low carbon and energy saving and emission reduction. To use scientific planting and monitoring methods, soil properties, carbon sequestration of soil organic carbon pool, and carbon sequestration capacity of different species of trees were studied and monitored. High carbon sequestration species selection, silvicultural management, measurement of carbon sink and carbon monitoring are explored.

Effects of lanthanum and acid rain stress on the bio-sequestration of lanthanum in phytoliths in germinated rice seeds

PubMed Central

Si, Yong; Wang, Lihong; Huang, Xiaohua

2018-01-01

REEs in the environment can be absorbed by plants and sequestered by plant phytoliths. Acid rain can directly or indirectly affect plant physiological functions. Currently, the effects of REEs and acid rain on phytolith-REEs complex in plants are not yet fully understood. In this study, a high-silicon accumulation crop, rice (Oryza sativa L.), was selected as a representative of plants, and orthogonal experiments were conducted under various levels of lanthanum [La(III)] and pH. The results showed that various La(III) concentrations could significantly improve the efficiency and sequestration of phytolith La(III) in germinated rice seeds. A pH of 4.5 promoted phytolith La(III) sequestration, while a pH of 3.5 inhibited sequestration. Compared with the single treatment with La(III), the combination of La(III) and acid rain inhibited the efficiency and sequestration of phytolith La(III). Correlation analysis showed that the efficiency of phytolith La(III) sequestration had no correlation with the production of phytolith but was closely correlated with the sequestration of phytolith La(III) and the physiological changes of germinated rice seeds. Phytolith morphology was an important factor affecting phytolith La(III) sequestration in germinated rice seeds, and the effect of tubes on sequestration was more significant than that of dumbbells. This study demonstrated that the formation of the phytolith and La(III) complex could be affected by exogenous La(III) and acid rain in germinated rice seeds. PMID:29763463

Soil Carbon Sequestration and Land-Use Change: Processes and Potential

DOE Data Explorer

Post, W. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kwon, K. C. [Tuskeegee University, Tuskeegee, AL (United States)

2005-01-01

When agricultural land is no longer used for cultivation and allowed to revert to natural vegetation or replanted to perennial vegetation, soil organic carbon can accumulate. This accumulation process essentially reverses some of the effects responsible for soil organic carbon losses from when the land was converted from perennial vegetation. We discuss the essential elements of what is known about soil organic matter dynamics that may result in enhanced soil carbon sequestration with changes in land-use and soil management. We review literature that reports changes in soil organic carbon after changes in land-use that favour carbon accumulation. This data summary provides a guide to approximate rates of SOC sequestration that are possible with management, and indicates the relative importance of some factors that influence the rates of organic carbon sequestration in soil. There is a large variation in the length of time for and the rate at which carbon may accumulate in soil, related to the productivity of the recovering vegetation, physical and biological conditions in the soil, and the past history of soil organic carbon inputs and physical disturbance. Maximum rates of C accumulation during the early aggrading stage of perennial vegetation growth, while substantial, are usually much less than 100g C m–2 y–1. Average rates of accumulation are similar for forest or grassland establishment: 33.8 g C m–2 y–1 and 33.2 g C m–2 y–1, respectively. These observed rates of soil organic C accumulation, when combined with the small amount of land area involved, are insufficient to account for a significant fraction of the missing C in the global carbon cycle as accumulating in the soils of formerly agricultural land.

Assessing the Feasibility and Risks of Using Wave-Driven Upwelling Pumps to Enhance the Biological Sequestration of Carbon in Open Oceans

NASA Astrophysics Data System (ADS)

White, A.; Bjorkman, K.; Grabowski, E.; Letelier, R. M.; Poulos, S.; Watkins, B.; Karl, D. M.

2008-12-01

In 1976, John D. Isaacs proposed to use wave energy to pump cold and nutrient-rich deep water into the sunlit surface layers. The motivation for this endeavor has taken many forms over the years, from energy production to fueling aquaculture to the more recent suggestion that artificial upwelling could be used to stimulate primary productivity and anthropogenic carbon sequestration in oligotrophic regions of the ocean. However, the potential for biological carbon sequestration in response to upwelling will depend on the concentration of nutrients relative to that of dissolved inorganic carbon in the water being upwelled and on the response of the marine microbial assemblage to this nutrient enrichment. In June 2008, we tested a commercially available wave pump in the vicinity of Station ALOHA, north of Oahu, Hawaii in order to assess the logistics of at-sea deployment and the survivability of the equipment in the open ocean. Our engineering test was also designed to evaluate a recently published hypothesis (Karl and Letelier, 2008, Marine Ecology Progress Series) that upwelling of water containing excess phosphate relative to nitrogen compared to the canonical "Redfield" molar ratio of 16N:1P, would generate a two-phased phytoplankton bloom and enhance carbon sequestration. In this presentation, we analyze the results of this field test within the context of pelagic biogeochemical cycles. Furthermore, we discuss the deployment of a 300m wave pump, efforts to sample a biochemical response, the engineering challenges faced and the practical and ethical implications of these results for future experiments aimed at stimulating the growth of phytoplankton in oligotrophic regions.

A rock physics and seismic reservoir characterization study of the Rock Springs Uplift, a carbon dioxide sequestration site in Southwestern Wyoming

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grana, Dario; Verma, Sumit; Pafeng, Josiane

We present a reservoir geophysics study, including rock physics modeling and seismic inversion, of a carbon dioxide sequestration site in Southwestern Wyoming, namely the Rock Springs Uplift, and build a petrophysical model for the potential injection reservoirs for carbon dioxide sequestration. Our objectives include the facies classification and the estimation of the spatial model of porosity and permeability for two sequestration targets of interest, the Madison Limestone and the Weber Sandstone. The available dataset includes a complete set of well logs at the location of the borehole available in the area, a set of 110 core samples, and a seismicmore » survey acquired in the area around the well. The proposed study includes a formation evaluation analysis and facies classification at the well location, the calibration of a rock physics model to link petrophysical properties and elastic attributes using well log data and core samples, the elastic inversion of the pre-stack seismic data, and the estimation of the reservoir model of facies, porosity and permeability conditioned by seismic inverted elastic attributes and well log data. In particular, the rock physics relations are facies-dependent and include granular media equations for clean and shaley sandstone, and inclusion models for the dolomitized limestone. The permeability model has been computed by applying a facies-dependent porosity-permeability relation calibrated using core sample measurements. Finally, the study shows that both formations show good storage capabilities. The Madison Limestone includes a homogeneous layer of high-porosity high-permeability dolomite; the Weber Sandstone is characterized by a lower average porosity but the layer is thicker than the Madison Limestone.« less

A rock physics and seismic reservoir characterization study of the Rock Springs Uplift, a carbon dioxide sequestration site in Southwestern Wyoming

DOE PAGES

Grana, Dario; Verma, Sumit; Pafeng, Josiane; ...

2017-06-20

We present a reservoir geophysics study, including rock physics modeling and seismic inversion, of a carbon dioxide sequestration site in Southwestern Wyoming, namely the Rock Springs Uplift, and build a petrophysical model for the potential injection reservoirs for carbon dioxide sequestration. Our objectives include the facies classification and the estimation of the spatial model of porosity and permeability for two sequestration targets of interest, the Madison Limestone and the Weber Sandstone. The available dataset includes a complete set of well logs at the location of the borehole available in the area, a set of 110 core samples, and a seismicmore » survey acquired in the area around the well. The proposed study includes a formation evaluation analysis and facies classification at the well location, the calibration of a rock physics model to link petrophysical properties and elastic attributes using well log data and core samples, the elastic inversion of the pre-stack seismic data, and the estimation of the reservoir model of facies, porosity and permeability conditioned by seismic inverted elastic attributes and well log data. In particular, the rock physics relations are facies-dependent and include granular media equations for clean and shaley sandstone, and inclusion models for the dolomitized limestone. The permeability model has been computed by applying a facies-dependent porosity-permeability relation calibrated using core sample measurements. Finally, the study shows that both formations show good storage capabilities. The Madison Limestone includes a homogeneous layer of high-porosity high-permeability dolomite; the Weber Sandstone is characterized by a lower average porosity but the layer is thicker than the Madison Limestone.« less

A Policy Option To Provide Sufficient Funding For Massive-Scale Sequestration of CO2

NASA Astrophysics Data System (ADS)

Kithil, P. W.

2007-12-01

Global emissions of CO2 now are nearly 30 billion tons per year, and are growing rapidly due to strong economic growth. Atmospheric levels of CO2 have reached 380 ppm and recent reports suggest the rate of increase has gone from 1% per year in the 1990's to 3% per year now - with potential to cross 550ppm in the 2020 decade. Without stabilization of atmospheric CO2 below 550ppm, climate models predict unacceptably higher average temperatures with significant risk of runaway global warming this century. While there is much talk about reducing CO2 emissions by switching to non-fossil energy sources, imposing energy efficiency, and a host of other changes, there are no new large-scale energy sources on the horizon. The options are to impose draconian cuts in fossil energy consumption that will keep us below 550ppm (devastating the global economy) - or to adopt massive-scale sequestration of CO2. Three approaches are feasible: biological ocean sequestration, geologic sequestration, and biological terrestrial sequestration. Biological sequestration is applicable to all CO2 sources, whereas geologic sequestration is limited to fossil-fuel power plants and some large point-source emitters such as cement plants and large industrial facilities. Sequestration provides a direct mechanism for reducing atmospheric levels of CO2, whereas offsetting technologies such as wind power or improved efficiency, reduce the need for more fossil fuels but do not physically remove CO2 from the environment. The primary geologic technique, carbon capture & sequestration (CCS), prevents CO2 from entering the atmosphere but likewise does not reduce existing levels of atmospheric CO2. Biological sequestration (ocean or terrestrial) physically removes CO2 from the atmosphere. Since we cannot shut down our global economy, urgent action is needed to counteract CO2 emissions, and avoid catastrophic climate change. Given the long lead time and/or small impact of offsetting energy sources, sequestration is the only way to achieve near and medium-term reductions in atmospheric CO2 levels. To finance massive-scale sequestration of CO2, we propose the World Trade Organization (WTO) become an active player in the sequestration market. Given the WTO's role as overseer of international trade agreements annually representing 30 trillion in imports and exports of goods and services, it is by far the largest global economic force and therefore offers the broadest economic base. Absent a real solution to CO2 emissions, the global economy - and world trade - will shrink dramatically. The WTO can jumpstart the market for CO2 sequestration by issuing long term contracts to purchase bona fide sequestration-derived CO2 credits. Under this proposal, an initial price of 100 per ton which steps-down by 5% per year could bring forth the sequestration investment needed to achieve upwards of 10 billion tons sequestered CO2 per year by 2025 (seven billion tons from biological ocean sequestration and at least three billion tons from geologic and terrestrial sequestration). Assuming a contract term of 40 years, and a parallel commodity market continues to develop for CO2 credits, at some time in the future the WTO's contractual price will be less than the commodity market price - and the WTO begins to recover its investment. Under one set of assumptions, the net WTO annual subsidy would peak at $86 billion by 2022, equal to an across-the-board WTO tariff on imports and exports of about 1.01%, then become positive a few years later as the market price climbed above WTO's contracted price. Under this proposal, the WTO effectively subsidizes CO2 sequestration in the near to medium term and then recoups its investment and reaps large profits over the long term.

An Overview of Geologic Carbon Sequestration Potential in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cameron Downey; John Clinkenbeard

2005-10-01

As part of the West Coast Regional Carbon Sequestration Partnership (WESTCARB), the California Geological Survey (CGS) conducted an assessment of geologic carbon sequestration potential in California. An inventory of sedimentary basins was screened for preliminary suitability for carbon sequestration. Criteria included porous and permeable strata, seals, and depth sufficient for critical state carbon dioxide (CO{sub 2}) injection. Of 104 basins inventoried, 27 met the criteria for further assessment. Petrophysical and fluid data from oil and gas reservoirs was used to characterize both saline aquifers and hydrocarbon reservoirs. Where available, well log or geophysical information was used to prepare basin-wide mapsmore » showing depth-to-basement and gross sand distribution. California's Cenozoic marine basins were determined to possess the most potential for geologic sequestration. These basins contain thick sedimentary sections, multiple saline aquifers and oil and gas reservoirs, widespread shale seals, and significant petrophysical data from oil and gas operations. Potential sequestration areas include the San Joaquin, Sacramento, Ventura, Los Angeles, and Eel River basins, followed by the smaller Salinas, La Honda, Cuyama, Livermore, Orinda, and Sonoma marine basins. California's terrestrial basins are generally too shallow for carbon sequestration. However, the Salton Trough and several smaller basins may offer opportunities for localized carbon sequestration.« less

Predicting long-term carbon sequestration in response to CO 2 enrichment: How and why do current ecosystem models differ?

DOE PAGES

Walker, Anthony P.; Zaehle, Sönke; Medlyn, Belinda E.; ...

2015-04-27

Large uncertainty exists in model projections of the land carbon (C) sink response to increasing atmospheric CO 2. Free-Air CO 2 Enrichment (FACE) experiments lasting a decade or more have investigated ecosystem responses to a step change in atmospheric CO 2 concentration. To interpret FACE results in the context of gradual increases in atmospheric CO 2 over decades to centuries, we used a suite of seven models to simulate the Duke and Oak Ridge FACE experiments extended for 300 years of CO 2 enrichment. We also determine key modeling assumptions that drive divergent projections of terrestrial C uptake and evaluatemore » whether these assumptions can be constrained by experimental evidence. All models simulated increased terrestrial C pools resulting from CO 2 enrichment, though there was substantial variability in quasi-equilibrium C sequestration and rates of change. In two of two models that assume that plant nitrogen (N) uptake is solely a function of soil N supply, the net primary production response to elevated CO 2 became progressively N limited. In four of five models that assume that N uptake is a function of both soil N supply and plant N demand, elevated CO 2 led to reduced ecosystem N losses and thus progressively relaxed nitrogen limitation. Many allocation assumptions resulted in increased wood allocation relative to leaves and roots which reduced the vegetation turnover rate and increased C sequestration. Additionally, self-thinning assumptions had a substantial impact on C sequestration in two models. As a result, accurate representation of N process dynamics (in particular N uptake), allocation, and forest self-thinning is key to minimizing uncertainty in projections of future C sequestration in response to elevated atmospheric CO 2.« less

Soil carbon sequestration and biochar as negative emission technologies.

PubMed

Smith, Pete

2016-03-01

Despite 20 years of effort to curb emissions, greenhouse gas (GHG) emissions grew faster during the 2000s than in the 1990s, which presents a major challenge for meeting the international goal of limiting warming to <2 °C relative to the preindustrial era. Most recent scenarios from integrated assessment models require large-scale deployment of negative emissions technologies (NETs) to reach the 2 °C target. A recent analysis of NETs, including direct air capture, enhanced weathering, bioenergy with carbon capture and storage and afforestation/deforestation, showed that all NETs have significant limits to implementation, including economic cost, energy requirements, land use, and water use. In this paper, I assess the potential for negative emissions from soil carbon sequestration and biochar addition to land, and also the potential global impacts on land use, water, nutrients, albedo, energy and cost. Results indicate that soil carbon sequestration and biochar have useful negative emission potential (each 0.7 GtCeq. yr(-1) ) and that they potentially have lower impact on land, water use, nutrients, albedo, energy requirement and cost, so have fewer disadvantages than many NETs. Limitations of soil carbon sequestration as a NET centre around issues of sink saturation and reversibility. Biochar could be implemented in combination with bioenergy with carbon capture and storage. Current integrated assessment models do not represent soil carbon sequestration or biochar. Given the negative emission potential of SCS and biochar and their potential advantages compared to other NETs, efforts should be made to include these options within IAMs, so that their potential can be explored further in comparison with other NETs for climate stabilization. © 2016 John Wiley & Sons Ltd.

40 CFR 98.448 - Geologic sequestration monitoring, reporting, and verification (MRV) plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Sequestration of Carbon Dioxide § 98.448 Geologic sequestration monitoring, reporting, and verification (MRV... use to calculate site-specific variables for the mass balance equation. This includes, but is not...

40 CFR 98.448 - Geologic sequestration monitoring, reporting, and verification (MRV) plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Sequestration of Carbon Dioxide § 98.448 Geologic sequestration monitoring, reporting, and verification (MRV... use to calculate site-specific variables for the mass balance equation. This includes, but is not...

Lead sequestration and species redistribution during soil organic matter decomposition

USGS Publications Warehouse

Schroth, A.W.; Bostick, B.C.; Kaste, J.M.; Friedland, A.J.

2008-01-01

The turnover of soil organic matter (SOM) maintains a dynamic chemical environment in the forest floor that can impact metal speciation on relatively short timescales. Here we measure the speciation of Pb in controlled and natural organic (O) soil horizons to quantify changes in metal partitioning during SOM decomposition in different forest litters. We provide a link between the sequestration of pollutant Pb in O-horizons, estimated by forest floor Pb inventories, and speciation using synchrotron-based X-ray fluorescence and X-ray absorption spectroscopy. When Pb was introduced to fresh forest Oi samples, it adsorbed primarily to SOM surfaces, but as decomposition progressed over two years in controlled experiments, up to 60% of the Pb was redistributed to pedogenic birnessite and ferrihydrite surfaces. In addition, a significant fraction of pollutant Pb in natural soil profiles was associated with similar mineral phases (???20-35%) and SOM (???65-80%). Conifer forests have at least 2-fold higher Pb burdens in the forest floor relative to deciduous forests due to more efficient atmospheric scavenging and slower organic matter turnover. We demonstrate that pedogenic minerals play an important role in surface soil Pb sequestration, particularly in deciduous forests, and should be considered in any assessment of pollutant Pb mobility. ?? 2008 American Chemical Society.

Efficiency of incentives to jointly increase carbon sequestration and species conservation on a landscape

PubMed Central

Nelson, Erik; Polasky, Stephen; Lewis, David J.; Plantinga, Andrew J.; Lonsdorf, Eric; White, Denis; Bael, David; Lawler, Joshua J.

2008-01-01

We develop an integrated model to predict private land-use decisions in response to policy incentives designed to increase the provision of carbon sequestration and species conservation across heterogeneous landscapes. Using data from the Willamette Basin, Oregon, we compare the provision of carbon sequestration and species conservation under five simple policies that offer payments for conservation. We evaluate policy performance compared with the maximum feasible combinations of carbon sequestration and species conservation on the landscape for various conservation budgets. None of the conservation payment policies produce increases in carbon sequestration and species conservation that approach the maximum potential gains on the landscape. Our results show that policies aimed at increasing the provision of carbon sequestration do not necessarily increase species conservation and that highly targeted policies do not necessarily do as well as more general policies. PMID:18621703

Impacts of land use and climate change on carbon dynamics in south-central Senegal

USGS Publications Warehouse

Liu, Shu-Guang; Kaire, M.; Wood, Eric C.; Diallo, O.; Tieszen, Larry L.

2004-01-01

Total carbon stock in vegetation and soils was reduced 37% in south-central Senegal from 1900 to 2000. The decreasing trend will continue during the 21st century unless forest clearing is stopped, selective logging dramatically reduced, and climate change, if any, relatively small. Developing a sustainable fuelwood and charcoal production system could be the most feasible and significant carbon sequestration project in the region. If future climate changes dramatically as some models have predicted, cropland productivity will drop more than 65% around 2100, posing a serious threat to food security and the efficiency of carbon sequestration projects.

Engineered Escherichia coli with Periplasmic Carbonic Anhydrase as a Biocatalyst for CO2 Sequestration

PubMed Central

Jo, Byung Hoon; Kim, Im Gyu; Seo, Jeong Hyun; Kang, Dong Gyun

2013-01-01

Carbonic anhydrase is an enzyme that reversibly catalyzes the hydration of carbon dioxide (CO2). It has been suggested recently that this remarkably fast enzyme can be used for sequestration of CO2, a major greenhouse gas, making this a promising alternative for chemical CO2 mitigation. To promote the economical use of enzymes, we engineered the carbonic anhydrase from Neisseria gonorrhoeae (ngCA) in the periplasm of Escherichia coli, thereby creating a bacterial whole-cell catalyst. We then investigated the application of this system to CO2 sequestration by mineral carbonation, a process with the potential to store large quantities of CO2. ngCA was highly expressed in the periplasm of E. coli in a soluble form, and the recombinant bacterial cell displayed the distinct ability to hydrate CO2 compared with its cytoplasmic ngCA counterpart and previously reported whole-cell CA systems. The expression of ngCA in the periplasm of E. coli greatly accelerated the rate of calcium carbonate (CaCO3) formation and exerted a striking impact on the maximal amount of CaCO3 produced under conditions of relatively low pH. It was also shown that the thermal stability of the periplasmic enzyme was significantly improved. These results demonstrate that the engineered bacterial cell with periplasmic ngCA can successfully serve as an efficient biocatalyst for CO2 sequestration. PMID:23974145

Carbon sequestration is related to mycorrhizal fungal community shifts during long-term succession in boreal forests.

PubMed

Clemmensen, Karina E; Finlay, Roger D; Dahlberg, Anders; Stenlid, Jan; Wardle, David A; Lindahl, Björn D

2015-03-01

Boreal forest soils store a major proportion of the global terrestrial carbon (C) and below-ground inputs contribute as much as above-ground plant litter to the total C stored in the soil. A better understanding of the dynamics and drivers of root-associated fungal communities is essential to predict long-term soil C storage and climate feedbacks in northern ecosystems. We used 454-pyrosequencing to identify fungal communities across fine-scaled soil profiles in a 5000 yr fire-driven boreal forest chronosequence, with the aim of pinpointing shifts in fungal community composition that may underlie variation in below-ground C sequestration. In early successional-stage forests, higher abundance of cord-forming ectomycorrhizal fungi (such as Cortinarius and Suillus species) was linked to rapid turnover of mycelial biomass and necromass, efficient nitrogen (N) mobilization and low C sequestration. In late successional-stage forests, cord formers declined, while ericoid mycorrhizal ascomycetes continued to dominate, potentially facilitating long-term humus build-up through production of melanized hyphae that resist decomposition. Our results suggest that cord-forming ectomycorrhizal fungi and ericoid mycorrhizal fungi play opposing roles in below-ground C storage. We postulate that, by affecting turnover and decomposition of fungal tissues, mycorrhizal fungal identity and growth form are critical determinants of C and N sequestration in boreal forests. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Development and validation of a testing protocol for carbon sequestration using a controlled environment.

DOT National Transportation Integrated Search

2012-05-01

Carbon footprints, carbon credits and associated carbon sequestration techniques are rapidly becoming part : of how environmental mitigation business is conducted, not only in Texas but globally. Terrestrial carbon : sequestration is the general term...

Carbon dioxide (CO2) sequestration in deep saline aquifers and formations: Chapter 3

USGS Publications Warehouse

Rosenbauer, Robert J.; Thomas, Burt

2010-01-01

Carbon dioxide (CO2) capture and sequestration in geologic media is one among many emerging strategies to reduce atmospheric emissions of anthropogenic CO2. This chapter looks at the potential of deep saline aquifers – based on their capacity and close proximity to large point sources of CO2 – as repositories for the geologic sequestration of CO2. The petrochemical characteristics which impact on the suitability of saline aquifers for CO2 sequestration and the role of coupled geochemical transport models and numerical tools in evaluating site feasibility are also examined. The full-scale commercial CO2 sequestration project at Sleipner is described together with ongoing pilot and demonstration projects.

Making carbon sequestration a paying proposition

NASA Astrophysics Data System (ADS)

Han, Fengxiang X.; Lindner, Jeff S.; Wang, Chuji

2007-03-01

Atmospheric carbon dioxide (CO2) has increased from a preindustrial concentration of about 280 ppm to about 367 ppm at present. The increase has closely followed the increase in CO2 emissions from the use of fossil fuels. Global warming caused by increasing amounts of greenhouse gases in the atmosphere is the major environmental challenge for the 21st century. Reducing worldwide emissions of CO2 requires multiple mitigation pathways, including reductions in energy consumption, more efficient use of available energy, the application of renewable energy sources, and sequestration. Sequestration is a major tool for managing carbon emissions. In a majority of cases CO2 is viewed as waste to be disposed; however, with advanced technology, carbon sequestration can become a value-added proposition. There are a number of potential opportunities that render sequestration economically viable. In this study, we review these most economically promising opportunities and pathways of carbon sequestration, including reforestation, best agricultural production, housing and furniture, enhanced oil recovery, coalbed methane (CBM), and CO2 hydrates. Many of these terrestrial and geological sequestration opportunities are expected to provide a direct economic benefit over that obtained by merely reducing the atmospheric CO2 loading. Sequestration opportunities in 11 states of the Southeast and South Central United States are discussed. Among the most promising methods for the region include reforestation and CBM. The annual forest carbon sink in this region is estimated to be 76 Tg C/year, which would amount to an expenditure of 11.1-13.9 billion/year. Best management practices could enhance carbon sequestration by 53.9 Tg C/year, accounting for 9.3% of current total annual regional greenhouse gas emission in the next 20 years. Annual carbon storage in housing, furniture, and other wood products in 1998 was estimated to be 13.9 Tg C in the region. Other sequestration options, including the direct injection of CO2 in deep saline aquifers, mineralization, and biomineralization, are not expected to lead to direct economic gain. More detailed studies are needed for assessing the ultimate changes to the environment and the associated indirect cost savings for carbon sequestration.

Making carbon sequestration a paying proposition.

PubMed

Han, Fengxiang X; Lindner, Jeff S; Wang, Chuji

2007-03-01

Atmospheric carbon dioxide (CO(2)) has increased from a preindustrial concentration of about 280 ppm to about 367 ppm at present. The increase has closely followed the increase in CO(2) emissions from the use of fossil fuels. Global warming caused by increasing amounts of greenhouse gases in the atmosphere is the major environmental challenge for the 21st century. Reducing worldwide emissions of CO(2) requires multiple mitigation pathways, including reductions in energy consumption, more efficient use of available energy, the application of renewable energy sources, and sequestration. Sequestration is a major tool for managing carbon emissions. In a majority of cases CO(2) is viewed as waste to be disposed; however, with advanced technology, carbon sequestration can become a value-added proposition. There are a number of potential opportunities that render sequestration economically viable. In this study, we review these most economically promising opportunities and pathways of carbon sequestration, including reforestation, best agricultural production, housing and furniture, enhanced oil recovery, coalbed methane (CBM), and CO(2) hydrates. Many of these terrestrial and geological sequestration opportunities are expected to provide a direct economic benefit over that obtained by merely reducing the atmospheric CO(2) loading. Sequestration opportunities in 11 states of the Southeast and South Central United States are discussed. Among the most promising methods for the region include reforestation and CBM. The annual forest carbon sink in this region is estimated to be 76 Tg C/year, which would amount to an expenditure of $11.1-13.9 billion/year. Best management practices could enhance carbon sequestration by 53.9 Tg C/year, accounting for 9.3% of current total annual regional greenhouse gas emission in the next 20 years. Annual carbon storage in housing, furniture, and other wood products in 1998 was estimated to be 13.9 Tg C in the region. Other sequestration options, including the direct injection of CO(2) in deep saline aquifers, mineralization, and biomineralization, are not expected to lead to direct economic gain. More detailed studies are needed for assessing the ultimate changes to the environment and the associated indirect cost savings for carbon sequestration.

Terrestrial Carbon Sequestration: Analysis of Terrestrial Carbon Sequestration at Three Contaminated Sites Remediated and Revitalized with Soil Amendments

EPA Pesticide Factsheets

This paper provides EPA's analysis of the data to determine carbon sequestration rates at three diverse sites that differ in geography/location, weather, soil properties, type of contamination, and age.

Terrestrial sequestration

ScienceCinema

Charlie Byrer

2017-12-09

Terrestrial sequestration is the enhancement of CO2 uptake by plants that grow on land and in freshwater and, importantly, the enhancement of carbon storage in soils where it may remain more permanently stored. Terrestrial sequestration provides an opportunity for low-cost CO2 emissions offsets.

An efficient approach to imaging underground hydraulic networks

NASA Astrophysics Data System (ADS)

Kumar, Mohi

2012-07-01

To better locate natural resources, treat pollution, and monitor underground networks associated with geothermal plants, nuclear waste repositories, and carbon dioxide sequestration sites, scientists need to be able to accurately characterize and image fluid seepage pathways below ground. With these images, scientists can gain knowledge of soil moisture content, the porosity of geologic formations, concentrations and locations of dissolved pollutants, and the locations of oil fields or buried liquid contaminants. Creating images of the unknown hydraulic environments underfoot is a difficult task that has typically relied on broad extrapolations from characteristics and tests of rock units penetrated by sparsely positioned boreholes. Such methods, however, cannot identify small-scale features and are very expensive to reproduce over a broad area. Further, the techniques through which information is extrapolated rely on clunky and mathematically complex statistical approaches requiring large amounts of computational power.

Transient dynamics of terrestrial carbon storage: Mathematical foundation and its applications

DOE PAGES

Luo, Yiqi; Shi, Zheng; Lu, Xingjie; ...

2017-01-12

Terrestrial ecosystems have absorbed roughly 30% of anthropogenic CO 2 emissions over the past decades, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling and experimental and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under global change is still not very clear. Here we develop a new framework for understanding transient dynamics of terrestrial C storage through mathematical analysis and numerical experiments. Our analysis indicates that the ultimate force driving ecosystem C storage change is the C storage capacity, which is jointly determined by ecosystem C input (e.g.,more » net primary production, NPP) and residence time. Since both C input and residence time vary with time, the C storage capacity is time-dependent and acts as a moving attractor that actual C storage chases. The rate of change in C storage is proportional to the C storage potential, which is the difference between the current storage and the storage capacity. The C storage capacity represents instantaneous responses of the land C cycle to external forcing, whereas the C storage potential represents the internal capability of the land C cycle to influence the C change trajectory in the next time step. The influence happens through redistribution of net C pool changes in a network of pools with different residence times. Moreover, this and our other studies have demonstrated that one matrix equation can replicate simulations of most land C cycle models (i.e., physical emulators). As a result, simulation outputs of those models can be placed into a three-dimensional (3-D) parameter space to measure their differences. The latter can be decomposed into traceable components to track the origins of model uncertainty. In addition, the physical emulators make data assimilation computationally feasible so that both C flux- and pool-related datasets can be used to better constrain model predictions of land C sequestration. Altogether, this new mathematical framework offers new approaches to understanding, evaluating, diagnosing, and improving land C cycle models.« less

Transient dynamics of terrestrial carbon storage: Mathematical foundation and its applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Yiqi; Shi, Zheng; Lu, Xingjie

Terrestrial ecosystems have absorbed roughly 30% of anthropogenic CO 2 emissions over the past decades, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling and experimental and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under global change is still not very clear. Here we develop a new framework for understanding transient dynamics of terrestrial C storage through mathematical analysis and numerical experiments. Our analysis indicates that the ultimate force driving ecosystem C storage change is the C storage capacity, which is jointly determined by ecosystem C input (e.g.,more » net primary production, NPP) and residence time. Since both C input and residence time vary with time, the C storage capacity is time-dependent and acts as a moving attractor that actual C storage chases. The rate of change in C storage is proportional to the C storage potential, which is the difference between the current storage and the storage capacity. The C storage capacity represents instantaneous responses of the land C cycle to external forcing, whereas the C storage potential represents the internal capability of the land C cycle to influence the C change trajectory in the next time step. The influence happens through redistribution of net C pool changes in a network of pools with different residence times. Moreover, this and our other studies have demonstrated that one matrix equation can replicate simulations of most land C cycle models (i.e., physical emulators). As a result, simulation outputs of those models can be placed into a three-dimensional (3-D) parameter space to measure their differences. The latter can be decomposed into traceable components to track the origins of model uncertainty. In addition, the physical emulators make data assimilation computationally feasible so that both C flux- and pool-related datasets can be used to better constrain model predictions of land C sequestration. Altogether, this new mathematical framework offers new approaches to understanding, evaluating, diagnosing, and improving land C cycle models.« less

Geological Carbon Sequestration in the Ohio River Valley: An Evaluation of Possible Target Formations

NASA Astrophysics Data System (ADS)

Dalton, T. A.; Daniels, J. J.

2009-12-01

The development of geological carbon sequestration within the Ohio River Valley is of major interest to the national electricity and coal industries because the Valley is home to a heavy concentration of coal-burning electricity generation plants and the infrastructure is impossible to eliminate in the short-term. It has been determined by Ohio's politicians and citizenry that the continued use of coal in this region until alternative energy supplies are available will be necessary over the next few years. Geologic sequestration is the only possible means of keeping the CO2 out of the atmosphere in the region. The cost of the sequestration effort greatly decreases CO2 emissions by sequestering CO2 directly on site of these plants, or by minimizing the distance between fossil-fueled generation and sequestration (i.e., by eliminating the cost of transportation of supercritical CO2 from plant to sequestration site). Thus, the practicality of CO2 geologic sequestration within the Ohio River Valley is central to the development of such a commercial effort. Though extensive work has been done by the Regional Partnerships of the DOE/NETL in the characterization of general areas for carbon sequestration throughout the nation, few projects have narrowed their focus into a single geologic region in order to evaluate the sites of greatest commercial potential. As an undergraduate of the Earth Sciences at Ohio State, I have engaged in thorough research to obtain a detailed understanding of the geology of the Ohio River Valley and its potential for commercial-scale carbon sequestration. Through this research, I have been able to offer an estimate of the areas of greatest interest for CO2 geologic sequestration. This research has involved petrological, mineralogical, geochemical, and geophysical analyses of four major reservoir formations within Ohio—the Rose Run, the Copper Ridge, the Clinton, and the Oriskany—along with an evaluation of the possible effects of injection into these saline reservoirs.

Soil carbon sequestration potential for "grain for green" project in Loess Plateau, China

USGS Publications Warehouse

Chang, R.; Fu, B.; Liu, Gaisheng; Liu, S.

2011-01-01

Conversion of cropland into perennial vegetation land can increase soil organic carbon (SOC) accumulation, which might be an important mitigation measure to sequester carbon dioxide from the atmosphere. The “Grain for Green” project, one of the most ambitious ecological programmes launched in modern China, aims at transforming the low-yield slope cropland into grassland and woodland. The Loess Plateau in China is the most important target of this project due to its serious soil erosion. The objectives of this study are to answer three questions: (1) what is the rate of the SOC accumulation for this “Grain for Green” project in Loess Plateau? (2) Is there a difference in SOC sequestration among different restoration types, including grassland, shrub and forest? (3) Is the effect of restoration types on SOC accumulation different among northern, middle and southern regions of the Loess Plateau? Based on analysis of the data collected from the literature conducted in the Loess Plateau, we found that SOC increased at a rate of 0.712 TgC/year in the top 20 cm soil layer for 60 years under this project across the entire Loess Plateau. This was a relatively reliable estimation based on current data, although there were some uncertainties. Compared to grassland, forest had a significantly greater effect on SOC accumulation in middle and southern Loess Plateau but had a weaker effect in the northern Loess Plateau. There were no differences found in SOC sequestration between shrub and grassland across the entire Loess Plateau. Grassland had a stronger effect on SOC sequestration in the northern Loess Plateau than in the middle and southern regions. In contrast, forest could increase more SOC in the middle and southern Loess Plateau than in the northern Loess Plateau, whereas shrub had a similar effect on SOC sequestration across the Loess Plateau. Our results suggest that the “Grain for Green” project can significantly increase the SOC storage in Loess Plateau, and it is recommended to expand grassland and shrub areas in the northern Loess Plateau and forest in the middle and southern Loess Plateau to enhance the SOC sequestration in this area.

Physical and Biological Regulation of Carbon Sequestration in Tidal Marshes

NASA Astrophysics Data System (ADS)

Morris, J. T.; Callaway, J.

2017-12-01

The rate of carbon sequestration in tidal marshes is regulated by complex feedbacks among biological and physical factors including the rate of sea-level rise (SLR), biomass production, tidal amplitude, and the concentration of suspended sediment. We used the Marsh Equilibrium Model (MEM) to explore the effects on C-sequestration across a wide range of permutations of these variables. C-sequestration increased with the rate of SLR to a maximum, then down to a vanishing point at higher SLR when marshes convert to mudflats. An acceleration in SLR will increase C-sequestration in marshes that can keep pace, but at high rates of SLR this is only possible with high biomass and suspended sediment concentrations. We found that there were no feasible solutions at SLR >13 mm/yr for permutations of variables that characterize the great majority of tidal marshes, i.e., the equilibrium elevation exists below the lower vertical limit for survival of marsh vegetation. The rate of SLR resulting in maximum C-sequestration varies with biomass production. C-sequestration rates at SLR=1 mm/yr averaged only 36 g C m-2 yr-1, but at the highest maximum biomass tested (5000 g/m2) the mean C-sequestration reached 399 g C m-2 yr-1 at SLR = 14 mm/yr. The empirical estimate of C-sequestration in a core dated 50-years overestimates the theoretical long-term rate by 34% for realistic values of decomposition rate and belowground production. The overestimate of the empirical method arises from the live and decaying biomass contained within the carbon inventory above the marker horizon, and overestimates were even greater for shorter surface cores.

Dynamics and climate change mitigation potential of soil organic carbon sequestration.

PubMed

Sommer, Rolf; Bossio, Deborah

2014-11-01

When assessing soil organic carbon (SOC) sequestration and its climate change (CC) mitigation potential at global scale, the dynamic nature of soil carbon storage and interventions to foster it should be taken into account. Firstly, adoption of SOC-sequestration measures will take time, and reasonably such schemes could only be implemented gradually at large-scale. Secondly, if soils are managed as carbon sinks, then SOC will increase only over a limited time, up to the point when a new SOC equilibrium is reached. This paper combines these two processes and predicts potential SOC sequestration dynamics in agricultural land at global scale and the corresponding CC mitigation potential. Assuming that global governments would agree on a worldwide effort to gradually change land use practices towards turning agricultural soils into carbon sinks starting 2014, the projected 87-year (2014-2100) global SOC sequestration potential of agricultural land ranged between 31 and 64 Gt. This is equal to 1.9-3.9% of the SRES-A2 projected 87-year anthropogenic emissions. SOC sequestration would peak 2032-33, at that time reaching 4.3-8.9% of the projected annual SRES-A2 emission. About 30 years later the sequestration rate would have reduced by half. Thus, SOC sequestration is not a C wedge that could contribute increasingly to mitigating CC. Rather, the mitigation potential is limited, contributing very little to solving the climate problem of the coming decades. However, we deliberately did not elaborate on the importance of maintaining or increasing SOC for sustaining soil health, agro-ecosystem functioning and productivity; an issue of global significance that deserves proper consideration irrespectively of any potential additional sequestration of SOC. Copyright © 2014 Elsevier Ltd. All rights reserved.

Near-term deployment of carbon capture and sequestration from biorefineries in the United States.

PubMed

Sanchez, Daniel L; Johnson, Nils; McCoy, Sean T; Turner, Peter A; Mach, Katharine J

2018-05-08

Capture and permanent geologic sequestration of biogenic CO 2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO 2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source-sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO 2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO 2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO 2 A sequestration credit, analogous to existing CCS tax credits, of $60/tCO 2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO 2 credits, of $90/tCO 2 can incent 38 Mt of abatement. Aggregation of CO 2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO 2 This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. Copyright © 2018 the Author(s). Published by PNAS.

Near-term deployment of carbon capture and sequestration from biorefineries in the United States

PubMed Central

Johnson, Nils; McCoy, Sean T.; Turner, Peter A.; Mach, Katharine J.

2018-01-01

Capture and permanent geologic sequestration of biogenic CO2 emissions may provide critical flexibility in ambitious climate change mitigation. However, most bioenergy with carbon capture and sequestration (BECCS) technologies are technically immature or commercially unavailable. Here, we evaluate low-cost, commercially ready CO2 capture opportunities for existing ethanol biorefineries in the United States. The analysis combines process engineering, spatial optimization, and lifecycle assessment to consider the technical, economic, and institutional feasibility of near-term carbon capture and sequestration (CCS). Our modeling framework evaluates least cost source–sink relationships and aggregation opportunities for pipeline transport, which can cost-effectively transport small CO2 volumes to suitable sequestration sites; 216 existing US biorefineries emit 45 Mt CO2 annually from fermentation, of which 60% could be captured and compressed for pipeline transport for under $25/tCO2. A sequestration credit, analogous to existing CCS tax credits, of $60/tCO2 could incent 30 Mt of sequestration and 6,900 km of pipeline infrastructure across the United States. Similarly, a carbon abatement credit, analogous to existing tradeable CO2 credits, of $90/tCO2 can incent 38 Mt of abatement. Aggregation of CO2 sources enables cost-effective long-distance pipeline transport to distant sequestration sites. Financial incentives under the low-carbon fuel standard in California and recent revisions to existing federal tax credits suggest a substantial near-term opportunity to permanently sequester biogenic CO2. This financial opportunity could catalyze the growth of carbon capture, transport, and sequestration; improve the lifecycle impacts of conventional biofuels; support development of carbon-negative fuels; and help fulfill the mandates of low-carbon fuel policies across the United States. PMID:29686063

36 CFR 230.40 - Eligible practices for cost-share assistance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... regeneration or to ensure forest establishment and carbon sequestration. (3) Forest Stand Improvement—Practices to enhance growth and quality of wood fiber, special forest products, and carbon sequestration. (4... carbon sequestration in conjunction with agriculture, forest, and other land uses. (5) Water Quality...

Carbon sequestration and its role in the global carbon cycle

USGS Publications Warehouse

McPherson, Brian J.; Sundquist, Eric T.

2009-01-01

For carbon sequestration the issues of monitoring, risk assessment, and verification of carbon content and storage efficacy are perhaps the most uncertain. Yet these issues are also the most critical challenges facing the broader context of carbon sequestration as a means for addressing climate change. In response to these challenges, Carbon Sequestration and Its Role in the Global Carbon Cycle presents current perspectives and research that combine five major areas: • The global carbon cycle and verification and assessment of global carbon sources and sinks • Potential capacity and temporal/spatial scales of terrestrial, oceanic, and geologic carbon storage • Assessing risks and benefits associated with terrestrial, oceanic, and geologic carbon storage • Predicting, monitoring, and verifying effectiveness of different forms of carbon storage • Suggested new CO2 sequestration research and management paradigms for the future. The volume is based on a Chapman Conference and will appeal to the rapidly growing group of scientists and engineers examining methods for deliberate carbon sequestration through storage in plants, soils, the oceans, and geological repositories.

Working memory and language: skill-specific or domain-general relations to mathematics?

PubMed

Purpura, David J; Ganley, Colleen M

2014-06-01

Children's early mathematics skills develop in a cumulative fashion; foundational skills form a basis for the acquisition of later skills. However, non-mathematical factors such as working memory and language skills have also been linked to mathematical development at a broad level. Unfortunately, little research has been conducted to evaluate the specific relations of these two non-mathematical factors to individual aspects of early mathematics. Thus, the focus of this study was to determine whether working memory and language were related to only individual aspects of early mathematics or related to many components of early mathematics skills. A total of 199 4- to 6-year-old preschool and kindergarten children were assessed on a battery of early mathematics tasks as well as measures of working memory and language. Results indicated that working memory has a specific relation to only a few-but critically important-early mathematics skills and language has a broad relation to nearly all early mathematics skills. Copyright © 2014 Elsevier Inc. All rights reserved.

Preservice Elementary Mathematics Teachers' Level of Relating Mathematical Concepts in Daily Life Contexts

ERIC Educational Resources Information Center

Akkus, Oylum

2008-01-01

The purpose of this study was to investigate preservice elementary mathematics teachers' ability of relating mathematical concepts and daily life context. Two research questions were set; what is the preservice elementary mathematics teachers' level of relating mathematical concepts and daily life context regarding to their education year and…

75 FR 33613 - Notice of the Carbon Sequestration-Geothermal Energy-Science Joint Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-14

... Sequestration--Geothermal Energy--Science Joint Workshop AGENCY: Office of Energy Efficiency and Renewable Energy, DOE. ACTION: Notice of the Carbon Sequestration--Geothermal Energy--Science Joint Workshop... Carbon Storage and Geothermal Energy, June 15-16, 2010. Experts from industry, academia, national labs...

Mathematics Teachers' Perceptions of Their Students' Mathematical Competence: Relations to Mathematics Achievement, Affect, and Engagement in Singapore and Australia

ERIC Educational Resources Information Center

Areepattamannil, Shaljan; Kaur, Berinderjeet

2013-01-01

This study, drawing on data from the Trends in International Mathematics and Science Study (TIMSS) 2011, examined whether mathematics teachers' perceptions of their students' mathematical competence were related to mathematics achievement, affect toward mathematics, and engagement in mathematics lessons among Grade 8 students in Singapore and…

Experimental multi-phase H2O-CO2 brine interactions at elevated temperature and pressure: Implications for CO2 sequestration in deep-saline aquifers

USGS Publications Warehouse

Rosenbauer, R.; Koksalan, T.

2004-01-01

The burning of fossil fuel and other anthropogenic activities have caused a continuous and dramatic 30% increase of atmospheric CO2 over the past 150 yr. CO2 sequestration is increasingly being viewed as a tool for managing these anthropogenic CO2 emissions to the atmosphere. CO2-saturated brine-rock experiments were carried out to evaluate the effects of multiphase H2O-CO2 fluids on mineral equilibria and the potential for CO2 sequestration in mineral phases within deep-saline aquifers. Experimental results were generally consistent with theoretical thermodynamic calculations. The solubility of CO2 was enhanced in brines in the presence of both limestone and sandstone relative to brines alone. Reactions between CO2 saturated brines and arkosic sandstones were characterized by desiccation of the brine and changes in the chemical composition of the brine suggesting fixation of CO2 in mineral phases. These reactions were occurring on a measurable but kinetically slow time scale at 120??C.

MODELING THE ENDOCRINE CONTROL OF VITELLOGENIN PRODUCTION IN FEMALE RAINBOW TROUT

PubMed Central

Sundling, Kaitlin; Craciun, Gheorghe; Schultz, Irvin; Hook, Sharon; Nagler, James; Cavileer, Tim; Verducci, Joseph; Liu, Yushi; Kim, Jonghan; Hayton, William

2015-01-01

The rainbow trout endocrine system is sensitive to changes in annual day length, which is likely the principal environmental cue controlling its reproductive cycle. This study focuses on the endocrine regulation of vitellogenin (Vg) protein synthesis, which is the major egg yolk precursor in this fish species. We present a model of Vg production in female rainbow trout which incorporates a biological pathway beginning with sex steroid estradiol-17β levels in the plasma and concluding with Vg secretion by the liver and sequestration in the oocytes. Numerical simulation results based on this model are compared with experimental data for estrogen receptor mRNA, Vg mRNA, and Vg in the plasma from female rainbow trout over a normal annual reproductive cycle. We also analyze the response of the model to parameter changes. The model is subsequently tested against experimental data from female trout under a compressed photoperiod regime. Comparison of numerical and experimental results suggests the possibility of a time-dependent change in oocyte Vg uptake rate. This model is part of a larger effort that is developing a mathematical description of the endocrine control of reproduction in female rainbow trout. We anticipate that these mathematical and computational models will play an important role in future regulatory toxicity assessments and in the prediction of ecological risk. PMID:24506554

Mathematical Modeling of RNA-Based Architectures for Closed Loop Control of Gene Expression.

PubMed

Agrawal, Deepak K; Tang, Xun; Westbrook, Alexandra; Marshall, Ryan; Maxwell, Colin S; Lucks, Julius; Noireaux, Vincent; Beisel, Chase L; Dunlop, Mary J; Franco, Elisa

2018-05-08

Feedback allows biological systems to control gene expression precisely and reliably, even in the presence of uncertainty, by sensing and processing environmental changes. Taking inspiration from natural architectures, synthetic biologists have engineered feedback loops to tune the dynamics and improve the robustness and predictability of gene expression. However, experimental implementations of biomolecular control systems are still far from satisfying performance specifications typically achieved by electrical or mechanical control systems. To address this gap, we present mathematical models of biomolecular controllers that enable reference tracking, disturbance rejection, and tuning of the temporal response of gene expression. These controllers employ RNA transcriptional regulators to achieve closed loop control where feedback is introduced via molecular sequestration. Sensitivity analysis of the models allows us to identify which parameters influence the transient and steady state response of a target gene expression process, as well as which biologically plausible parameter values enable perfect reference tracking. We quantify performance using typical control theory metrics to characterize response properties and provide clear selection guidelines for practical applications. Our results indicate that RNA regulators are well-suited for building robust and precise feedback controllers for gene expression. Additionally, our approach illustrates several quantitative methods useful for assessing the performance of biomolecular feedback control systems.

76 FR 24007 - Notice of Intent To Prepare an Environmental Impact Statement for the Lake Charles Carbon Capture...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-29

... Charles Carbon Capture and Sequestration Project, Lake Charles, LA AGENCY: Department of Energy. ACTION... competitive process under the Industrial Carbon Capture and Sequestration (ICCS) Program. The Lake Charles Carbon Capture and Sequestration Project (Lake Charles CCS Project) would demonstrate: (1) advanced...

Intro to Carbon Sequestration

ScienceCinema

None

2017-12-09

NETL's Carbon Sequestration Program is helping to develop technologies to capture, purify, and store carbon dioxide (CO2) in order to reduce greenhouse gas emissions without adversely influencing energy use or hindering economic growth. Carbon sequestration technologies capture and store CO2 that would otherwise reside in the atmosphere for long periods of time.

Carbon dynamics and sequestration in urban turfgrass ecosystems

USDA-ARS?s Scientific Manuscript database

Urbanization is a global trend. Turfgrass covers 1.9% of land in the continental US. Here we review existing literature associated with carbon (C) pools, sequestration, and nitrous oxide emission of urban turfgrass ecosystems. Turfgrasses exhibit significant carbon sequestration (0.34–1.4 Mg ha-1 ye...

From sink to source: Regional variation in U.S. forest carbon futures

PubMed Central

Wear, David N.; Coulston, John W.

2015-01-01

The sequestration of atmospheric carbon (C) in forests has partially offset C emissions in the United States (US) and might reduce overall costs of achieving emission targets, especially while transportation and energy sectors are transitioning to lower-carbon technologies. Using detailed forest inventory data for the conterminous US, we estimate forests’ current net sequestration of atmospheric C to be 173 Tg yr−1, offsetting 9.7% of C emissions from transportation and energy sources. Accounting for multiple driving variables, we project a gradual decline in the forest C emission sink over the next 25 years (to 112 Tg yr−1) with regional differences. Sequestration in eastern regions declines gradually while sequestration in the Rocky Mountain region declines rapidly and could become a source of atmospheric C due to disturbances such as fire and insect epidemics. C sequestration in the Pacific Coast region stabilizes as forests harvested in previous decades regrow. Scenarios simulating climate-induced productivity enhancement and afforestation policies increase sequestration rates, but would not fully offset declines from aging and forest disturbances. Separating C transfers associated with land use changes from sequestration clarifies forests’ role in reducing net emissions and demonstrates that retention of forest land is crucial for protecting or enhancing sink strength. PMID:26558439

From sink to source: Regional variation in U.S. forest carbon futures.

PubMed

Wear, David N; Coulston, John W

2015-11-12

The sequestration of atmospheric carbon (C) in forests has partially offset C emissions in the United States (US) and might reduce overall costs of achieving emission targets, especially while transportation and energy sectors are transitioning to lower-carbon technologies. Using detailed forest inventory data for the conterminous US, we estimate forests' current net sequestration of atmospheric C to be 173 Tg yr(-1), offsetting 9.7% of C emissions from transportation and energy sources. Accounting for multiple driving variables, we project a gradual decline in the forest C emission sink over the next 25 years (to 112 Tg yr(-1)) with regional differences. Sequestration in eastern regions declines gradually while sequestration in the Rocky Mountain region declines rapidly and could become a source of atmospheric C due to disturbances such as fire and insect epidemics. C sequestration in the Pacific Coast region stabilizes as forests harvested in previous decades regrow. Scenarios simulating climate-induced productivity enhancement and afforestation policies increase sequestration rates, but would not fully offset declines from aging and forest disturbances. Separating C transfers associated with land use changes from sequestration clarifies forests' role in reducing net emissions and demonstrates that retention of forest land is crucial for protecting or enhancing sink strength.

Parasite Sequestration in Plasmodium falciparum Malaria: Spleen and Antibody Modulation of Cytoadherence of Infected Erythrocytes

NASA Astrophysics Data System (ADS)

David, Peter H.; Hommel, Marcel; Miller, Louis H.; Udeinya, Iroka J.; Oligino, Lynette D.

1983-08-01

Sequestration, the adherence of infected erythrocytes containing late developmental stages of the parasite (trophozoites and schizonts) to the endothelium of capillaries and venules, is characteristic of Plasmodium falciparum infections. We have studied two host factors, the spleen and antibody, that influence sequestration of P. falciparum in the squirrel monkey. Sequestration of trophozoite/schizont-infected erythrocytes that occurs in intact animals is reduced in splenectomized animals; in vitro, when infected blood is incubated with monolayers of human melanoma cells, trophozoite/schizont-infected erythrocytes from intact animals but not from splenectomized animals bind to the melanoma cells. The switch in cytoadherence characteristics of the infected erythrocytes from nonbinding to binding occurs with a cloned parasite. Immune serum can inhibit and reverse in vitro binding to melanoma cells of infected erythrocytes from intact animals. Similarly, antibody can reverse in vivo sequestration as shown by the appearance of trophozoite/schizont-infected erythrocytes in the peripheral blood of an intact animal after inoculation with immune serum. These results indicate that the spleen modulates the expression of parasite alterations of the infected erythrocyte membrane responsible for sequestration and suggest that the prevention and reversal of sequestration could be one of the effector mechanisms involved in antibody-mediated protection against P. falciparum malaria.

Site Development, Operations, and Closure Plan Topical Report 5 An Assessment of Geologic Carbon Sequestration Options in the Illinois Basin. Phase III

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finley, Robert; Payne, William; Kirksey, Jim

2015-06-01

The Midwest Geological Sequestration Consortium (MGSC) has partnered with Archer Daniels Midland Company (ADM) and Schlumberger Carbon Services to conduct a large-volume, saline reservoir storage project at ADM’s agricultural products processing complex in Decatur, Illinois. The Development Phase project, named the Illinois Basin Decatur Project (IBDP) involves the injection of 1 million tonnes of carbon dioxide (CO 2) into a deep saline formation of the Illinois Basin over a three-year period. This report focuses on objectives, execution, and lessons learned/unanticipated results from the site development (relating specifically to surface equipment), operations, and the site closure plan.

Development of Contextual Mathematics teaching Material integrated related sciences and realistic for students grade xi senior high school

NASA Astrophysics Data System (ADS)

Helma, H.; Mirna, M.; Edizon, E.

2018-04-01

Mathematics is often applied in physics, chemistry, economics, engineering, and others. Besides that, mathematics is also used in everyday life. Learning mathematics in school should be associated with other sciences and everyday life. In this way, the learning of mathematics is more realstic, interesting, and meaningful. Needs analysis shows that required contextual mathematics teaching materials integrated related sciences and realistic on learning mathematics. The purpose of research is to produce a valid and practical contextual mathematics teaching material integrated related sciences and realistic. This research is development research. The result of this research is a valid and practical contextual mathematics teaching material integrated related sciences and realistic produced

Relating soil biochemistry to sustainable crop production

USDA-ARS?s Scientific Manuscript database

Amino acids, amino sugars, carbohydrates, phenols, and fatty acids together comprise appreciable proportions of soil organic matter (SOM). Their cycling contribute to soil processes, including nitrogen availability, carbon sequestration and aggregation. For example, soil accumulation of phenols has ...

Human neutrophil elastase and collagenase sequestration with phosphorylated cotton wound dressings.

PubMed

Edwards, J Vincent; Howley, Phyllis S

2007-11-01

The design and preparation of wound dressings that redress the protease imbalance in chronic wounds is an important goal of wound healing and medical materials science. Chronic wounds contain high levels of tissue and cytokine-destroying proteases including matrix metalloprotease and neutrophil elastase. Thus, the lowering of excessive protease levels in the wound environment by wound dressing sequestration prevents the breakdown of extracellular matrix proteins and growth factors necessary for wound healing. Phosphorylated cotton wound dressings were prepared to target sequestration of proteases from chronic wound exudate through a cationic uptake binding mechanism involving salt bridge formation of the positively charged amino acid side chains of proteases with the phosphate counterions of the wound dressing fiber. Dressings were prepared by applying sodium hexametaphosphate and diammonium phosphate in separate formulations to cotton gauze by pad/dry/cure methods. Phosphorylated cotton dressings were assessed for their ability to lower elastase and collagenase activity. The phosphorylated cotton dressings lowered elastase and collagenase activity 40-80% more effectively than the untreated cotton wound dressings under conditions that mimic chronic wound exudate. Efficacy of the phosphorylated cotton was found to be related to the level of phosphorylation and a lower pH due to protonated phosphate at the surface of the dressing. The capacity of the modified gauze to sequester continued elastase secretions similar to that found in a chronic wound over a 24-h period was retained within a 80% retention of elastase sequestration and was dose-dependent. Copyright (c) 2007 Wiley Periodicals, Inc.

Infectious complications after surgical splenectomy in children with sickle cell disease

PubMed Central

Monaco, Cypriano Petrus; Fonseca, Patricia Belintani Blum; Braga, Josefina Aparecida Pellegrini

2015-01-01

OBJECTIVE: To evaluate the frequency of infectious complications in children with sickle cell disease (SCD) after surgical splenectomy for acute splenic sequestration crisis. METHODS: Retrospective cohort of children with SCD who were born after 2002 and were regularly monitored until July 2013. Patients were divided into two groups: cases (children with SCD who underwent surgical splenectomy after an episode of splenic sequestration) and controls (children with SCD who did not have splenic sequestration and surgical procedures), in order to compare the frequency of invasive infections (sepsis, meningitis, bacteremia with positive blood cultures, acute chest syndrome and/or pneumonia) by data collected from medical records. Data were analyzed by descriptive statistical analysis. RESULTS: 44 patients were included in the case group. The mean age at the time of splenectomy was 2.6 years (1-6.9 years) and the mean postoperative length of follow-up was 6.1 years (3.8-9.9 years). The control group consisted of 69 patients with a mean age at the initial follow-up visit of 5.6 months (1-49 months) and a mean length of follow-up of 7.2 years (4-10.3 years).All children received pneumococcal conjugate vaccine. No significant difference was observed between groups in relation to infections during the follow-up. CONCLUSIONS: Surgical splenectomy in children with sickle cell disease that had splenic sequestration did not affect the frequency of infectious complications during 6 years of clinical follow-up. PMID:25913493

Soil Carbon 4 per mille

NASA Astrophysics Data System (ADS)

Minasny, Budiman; van Wesemael, Bas

2017-04-01

The '4 per mille Soils for Food Security and Climate' was launched at the COP21 aiming to increase global soil organic matter stocks by 4 per mille (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia) and asked whether the 4 per mille initiative is feasible. This study highlights region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates generally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha-1), and at the first twenty years after implementation of best management practices. In addition, areas that have reached equilibrium but not at their saturation level will not be able to further increase their sequestration. We found that most studies on SOC sequestration globally only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille initiative was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille on global topsoil of agricultural land, SOC sequestration is about 3.6 Gt C per year, which effectively offset 40% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become viable. The challenge for cropping farmers is to find disruptive technologies that will further improve soil condition and deliver increased soil carbon. Progress in 4 per mille requires collaboration and communication between scientists, farmers, policy makers, and marketeers.

Training Students to Analyze Spatial and Temporal Heterogeneities in Reservoir and Seal Petrology, Mineralogy, and Geochemistry: Implications for CO{sub 2} Sequestration Prediction, Simulation, and Monitoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bowen, Brenda

The objective of this project was to expose and train multiple students in geological tools that are essential to reservoir characterization and geologic sequestration including but not limited to advanced petrological methods, mineralogical methods, and geochemical methods; core analysis, and geophysical well-log interpretation. These efforts have included training of multiple students through geologically based curriculum and research using advanced petrological, mineralogical, and geochemical methods. In whole, over the last 3+ years, this award has supported 5,828 hours of student research, supporting the work of several graduate and undergraduate students. They have all received training directly related to ongoing CO{sub 2}more » sequestration demonstrations. The students have all conducted original scientific research on topics related to understanding the importance of lithological, textural, and compositional variability in formations that are being targeted as CO{sub 2} sequestration reservoirs and seals. This research was linked to the Mount Simon Sandstone reservoir and overlying Eau Claire Formation seal in the Illinois Basin- a system where over one million tons of CO{sub 2} are actively being injected with the first large-scale demonstration of anthropogenic CO{sub 2} storage in the U.S. Student projects focused specifically on 1) reservoir porosity characterization and evaluation, 2) petrographic, mineralogical, and geochemical evidence of fluid-related diagenesis in the caprock, 3) textural changes in reservoir samples exposed to experimental CO{sub 2} + brine conditions, 4) controls on spatial heterogeneity in composition and texture in both the reservoir and seal, 5) the implications of small-scale fractures within the reservoir, and 6) petrographic and stable isotope analyses of carbonates in the seal to understand the burial history of the system. The student-led research associated with this project provided real-time and hands-on experience with a relevant CO{sub 2} system, provided relevant information to the regional partnerships who are working within these formations, and provides more broadly applicable understanding and method development for other carbon capture and storage systems.« less

Restoring Sustainable Forests on Appalachian Mined Lands for Wood Products, Renewable Energy, Carbon Sequestration, and Other Ecosystem Services

DOE Office of Scientific and Technical Information (OSTI.GOV)

James A. Burger; J. Galbraith; T. Fox

2005-12-01

The overall purpose of this project is to evaluate the biological and economic feasibility of restoring high-quality forests on mined land, and to measure carbon sequestration and wood production benefits that would be achieved from forest restoration procedures. We are currently estimating the acreage of lands in Virginia, West Virginia, Kentucky, Ohio, and Pennsylvania mined under SMCRA and reclaimed to non-forested post-mining land uses that are not currently under active management, and therefore can be considered as available for carbon sequestration. To determine actual sequestration under different forest management scenarios, a field study was installed as a 3 x 3more » factorial in a random complete block design with three replications at each of three locations, one each in Ohio, West Virginia, and Virginia. The treatments included three forest types (white pine, hybrid poplar, mixed hardwood) and three silvicultural regimes (competition control, competition control plus tillage, competition control plus tillage plus fertilization). Each individual treatment plot is 0.5 acres. Each block of nine plots is 4.5 acres, and the complete installation at each site is 13.5 acres. Regression models of chemical and physical soil properties were created in order to estimate the SOC content down the soil profile. Soil organic carbon concentration and volumetric percent of the fines decreased exponentially down the soil profile. The results indicated that one-third of the total SOC content on mined lands was found in the surface 0-13 cm soil layer, and more than two-thirds of it was located in the 0-53 cm soil profile. A relative estimate of soil density may be best in broad-scale mine soil mapping since actual D{sub b} values are often inaccurate and difficult to obtain in rocky mine soils. Carbon sequestration potential is also a function of silvicultural practices used for reforestation success. Weed control plus tillage may be the optimum treatment for hardwoods and white pine, as any increased growth resulting from fertilization may not offset the decreased survival that accompanied fertilization. Relative to carbon value, our analysis this quarter shows that although short-rotation hardwood management on reclaimed surface mined lands may have higher LEVs than traditional long-rotation hardwood management, it is only profitable in a limited set of circumstances.« less

Vegetation carbon sequestration in Chinese forests from 2010 to 2050.

PubMed

He, Nianpeng; Wen, Ding; Zhu, Jianxing; Tang, Xuli; Xu, Li; Zhang, Li; Hu, Huifeng; Huang, Mei; Yu, Guirui

2017-04-01

Forests store a large part of the terrestrial vegetation carbon (C) and have high C sequestration potential. Here, we developed a new forest C sequestration (FCS) model based on the secondary succession theory, to estimate vegetation C sequestration capacity in China's forest vegetation. The model used the field measurement data of 3161 forest plots and three future climate scenarios. The results showed that logistic equations provided a good fit for vegetation biomass with forest age in natural and planted forests. The FCS model has been verified with forest biomass data, and model uncertainty is discussed. The increment of vegetation C storage in China's forest vegetation from 2010 to 2050 was estimated as 13.92 Pg C, while the average vegetation C sequestration rate was 0.34 Pg C yr -1 with a 95% confidence interval of 0.28-0.42 Pg C yr -1 , which differed significantly between forest types. The largest contributor to the increment was deciduous broadleaf forest (37.8%), while the smallest was deciduous needleleaf forest (2.7%). The vegetation C sequestration rate might reach its maximum around 2020, although vegetation C storage increases continually. It is estimated that vegetation C sequestration might offset 6-8% of China's future emissions. Furthermore, there was a significant negative relationship between vegetation C sequestration rate and C emission rate in different provinces of China, suggesting that developed provinces might need to compensate for undeveloped provinces through C trade. Our findings will provide valuable guidelines to policymakers for designing afforestation strategies and forest C trade in China. © 2016 John Wiley & Sons Ltd.

Mathematics Self-Related Beliefs and Online Learning

ERIC Educational Resources Information Center

Ichinose, Cherie; Bonsangue, Martin

2016-01-01

This study examined students' mathematical self-related beliefs in an online mathematics course. Mathematical self-related beliefs of a sample of high school students learning mathematics online were compared with student response data from the 2012 Programme for International Student Assessment (PISA). The treatment group reported higher levels…

78 FR 28205 - Notice of Availability of the Draft Environmental Impact Statement for the Lake Charles Carbon...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-14

... Lake Charles Carbon Capture and Sequestration Project (DOE/EIS-0464D) AGENCY: U.S. Department of Energy...) announces the availability of the Lake Charles Carbon Capture and Sequestration Project Draft [[Page 28206... potential environmental impacts associated with the Lake Charles Carbon Capture and Sequestration Project...

Geochemical Impacts to Groundwater from Geologic Carbon Sequestration: Controls on pH and Inorganic Carbon Concentrations from Reaction Path and Kinetic Modeling

EPA Science Inventory

Geologic carbon sequestration has the potential to cause long-term reductions in global emissions of carbon dioxide to the atmosphere. Safe and effective application of carbon sequestration technology requires an understanding of the potential risks to the quality of underground...

Hurricane impacts on US forest carbon sequestration

Treesearch

Steven G. McNulty

2002-01-01

Recent focus has been given to US forests as a sink for increases in atmospheric carbon dioxide. Current estimates of US Forest carbon sequestration average approximately 20 Tg (i.e. 1012 g) year. However, predictions of forest carbon sequestration often do not include the influence of hurricanes on forest carbon storage. Intense hurricanes...

Integrated Mid-Continent Carbon Capture, Sequestration & Enhanced Oil Recovery Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brian McPherson

2010-08-31

A consortium of research partners led by the Southwest Regional Partnership on Carbon Sequestration and industry partners, including CAP CO2 LLC, Blue Source LLC, Coffeyville Resources, Nitrogen Fertilizers LLC, Ash Grove Cement Company, Kansas Ethanol LLC, Headwaters Clean Carbon Services, Black & Veatch, and Schlumberger Carbon Services, conducted a feasibility study of a large-scale CCS commercialization project that included large-scale CO{sub 2} sources. The overall objective of this project, entitled the 'Integrated Mid-Continent Carbon Capture, Sequestration and Enhanced Oil Recovery Project' was to design an integrated system of US mid-continent industrial CO{sub 2} sources with CO{sub 2} capture, and geologicmore » sequestration in deep saline formations and in oil field reservoirs with concomitant EOR. Findings of this project suggest that deep saline sequestration in the mid-continent region is not feasible without major financial incentives, such as tax credits or otherwise, that do not exist at this time. However, results of the analysis suggest that enhanced oil recovery with carbon sequestration is indeed feasible and practical for specific types of geologic settings in the Midwestern U.S.« less

Mathematics-Related Emotions among Finnish Adolescents across Different Performance Levels

ERIC Educational Resources Information Center

Holm, Marja Eliisa; Hannula, Markku Sakari; Björn, Piia Maria

2017-01-01

This study examined the relation of mathematics performance and gender with seven mathematics-related emotions (enjoyment, pride, anger, anxiety, shame, hopelessness and boredom) among adolescents. Using strict and lenient mathematics performance cut-off scores, respective groups of adolescents with mathematics difficulties (MD, n = 136), low (LA,…

Ocean sequestration of crop residue carbon: recycling fossil fuel carbon back to deep sediments.

PubMed

Strand, Stuart E; Benford, Gregory

2009-02-15

For significant impact any method to remove CO2 from the atmosphere must process large amounts of carbon efficiently, be repeatable, sequester carbon for thousands of years, be practical, economical and be implemented soon. The only method that meets these criteria is removal of crop residues and burial in the deep ocean. We show here that this method is 92% efficient in sequestration of crop residue carbon while cellulosic ethanol production is only 32% and soil sequestration is about 14% efficient. Deep ocean sequestration can potentially capture 15% of the current global CO2 annual increase, returning that carbon backto deep sediments, confining the carbon for millennia, while using existing capital infrastructure and technology. Because of these clear advantages, we recommend enhanced research into permanent sequestration of crop residues in the deep ocean.

Carbon sequestration efficiency of organic amendments in a long-term experiment on a vertisol in Huang-Huai-Hai Plain, China.

PubMed

Hua, Keke; Wang, Daozhong; Guo, Xisheng; Guo, Zibin

2014-01-01

Soil organic carbon (SOC) sequestration is important for improving soil fertility of cropland and for the mitigation of greenhouse gas emissions to the atmosphere. The efficiency of SOC sequestration depends on the quantity and quality of the organic matter, soil type, and climate. Little is known about the SOC sequestration efficiency of organic amendments in Vertisols. Thus, we conducted the research based on 29 years (1982-2011) of long-term fertilization experiment with a no fertilizer control and five fertilization regimes: CK (control, no fertilizer), NPK (mineral NPK fertilizers alone), NPK+1/2W (mineral NPK fertilizers combined with half the amount of wheat straw), NPK+W (mineral NPK fertilizers combined with full the amount of wheat straw), NPK+PM (mineral NPK fertilizers combined with pig manure) and NPK+CM (mineral NPK fertilizers combined cattle manure). Total mean annual C inputs were 0.45, 1.55, 2.66, 3.71, 4.68 and 6.56 ton/ha/yr for CK, NPK, NPKW1/2, NPKW, NPKPM and NPKCM, respectively. Mean SOC sequestration rate was 0.20 ton/ha/yr in the NPK treatment, and 0.39, 0.50, 0.51 and 0.97 ton/ha/yr in the NPKW1/2, NPKW, NPKPM, and NPKCM treatments, respectively. A linear relationship was observed between annual C input and SOC sequestration rate (SOCsequestration rate  = 0.16 Cinput -0.10, R = 0.95, P<0.01), suggesting a C sequestration efficiency of 16%. The Vertisol required an annual C input of 0.63 ton/ha/yr to maintain the initial SOC level. Moreover, the C sequestration efficiencies of wheat straw, pig manure and cattle manure were 17%, 11% and 17%, respectively. The results indicate that the Vertisol has a large potential to sequester SOC with a high efficiency, and applying cattle manure or wheat straw is a recommendable SOC sequestration practice in Vertisols.

Carbon Sequestration Efficiency of Organic Amendments in a Long-Term Experiment on a Vertisol in Huang-Huai-Hai Plain, China

PubMed Central

Hua, Keke; Wang, Daozhong; Guo, Xisheng; Guo, Zibin

2014-01-01

Soil organic carbon (SOC) sequestration is important for improving soil fertility of cropland and for the mitigation of greenhouse gas emissions to the atmosphere. The efficiency of SOC sequestration depends on the quantity and quality of the organic matter, soil type, and climate. Little is known about the SOC sequestration efficiency of organic amendments in Vertisols. Thus, we conducted the research based on 29 years (1982–2011) of long-term fertilization experiment with a no fertilizer control and five fertilization regimes: CK (control, no fertilizer), NPK (mineral NPK fertilizers alone), NPK+1/2W (mineral NPK fertilizers combined with half the amount of wheat straw), NPK+W (mineral NPK fertilizers combined with full the amount of wheat straw), NPK+PM (mineral NPK fertilizers combined with pig manure) and NPK+CM (mineral NPK fertilizers combined cattle manure). Total mean annual C inputs were 0.45, 1.55, 2.66, 3.71, 4.68 and 6.56 ton/ha/yr for CK, NPK, NPKW1/2, NPKW, NPKPM and NPKCM, respectively. Mean SOC sequestration rate was 0.20 ton/ha/yr in the NPK treatment, and 0.39, 0.50, 0.51 and 0.97 ton/ha/yr in the NPKW1/2, NPKW, NPKPM, and NPKCM treatments, respectively. A linear relationship was observed between annual C input and SOC sequestration rate (SOCsequestration rate  = 0.16 Cinput –0.10, R = 0.95, P<0.01), suggesting a C sequestration efficiency of 16%. The Vertisol required an annual C input of 0.63 ton/ha/yr to maintain the initial SOC level. Moreover, the C sequestration efficiencies of wheat straw, pig manure and cattle manure were 17%, 11% and 17%, respectively. The results indicate that the Vertisol has a large potential to sequester SOC with a high efficiency, and applying cattle manure or wheat straw is a recommendable SOC sequestration practice in Vertisols. PMID:25265095

Trading forest carbon

EPA Science Inventory

The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

Mathematics Anxiety in Young Children: Concurrent and Longitudinal Associations with Mathematical Performance

ERIC Educational Resources Information Center

Vukovic, Rose K.; Kieffer, Michael J.; Bailey, Sean P.; Harari, Rachel R.

2013-01-01

This study explored mathematics anxiety in a longitudinal sample of 113 children followed from second to third grade. We examined how mathematics anxiety related to different types of mathematical performance concurrently and longitudinally and whether the relations between mathematics anxiety and mathematical performance differed as a function of…

Combined global change effects on ecosystem processesin nine U.S. topographically complex areas

USGS Publications Warehouse

Hartman, Melannie D.; Baron, Jill S.; Ewing, Holly A.; Weathers, Kathleen

2014-01-01

Concurrent changes in climate, atmospheric nitrogen (N) deposition, and increasing levels of atmospheric carbon dioxide (CO2) affect ecosystems in complex ways. The DayCent-Chem model was used to investigate the combined effects of these human-caused drivers of change over the period 1980–2075 at seven forested montane and two alpine watersheds in the United States. Net ecosystem production (NEP) increased linearly with increasing N deposition for six out of seven forested watersheds; warming directly increased NEP at only two of these sites. Warming reduced soil organic carbon storage at all sites by increasing heterotrophic respiration. At most sites, warming together with high N deposition increased nitrous oxide (N2O) emissions enough to negate the greenhouse benefit of soil carbon sequestration alone, though there was a net greenhouse gas sink across nearly all sites mainly due to the effect of CO2 fertilization and associated sequestration by plants. Over the simulation period, an increase in atmospheric CO2 from 350 to 600 ppm was the main driver of change in net ecosystem greenhouse gas sequestration at all forested sites and one of two alpine sites, but an additional increase in CO2 from 600 to 760 ppm produced smaller effects. Warming either increased or decreased net greenhouse gas sequestration, depending on the site. The N contribution to net ecosystem greenhouse gas sequestration averaged across forest sites was only 5–7 % and was negligible for the alpine. Stream nitrate (NO3−) fluxes increased sharply with N-loading, primarily at three watersheds where initial N deposition values were high relative to terrestrial N uptake capacity. The simulated results displayed fewer synergistic responses to warming, N-loading, and CO2 fertilization than expected. Overall, simulations with DayCent-Chem suggest individual site characteristics and historical patterns of N deposition are important determinants of forest or alpine ecosystem responses to global change.

Modeling of CO 2 sequestration in coal seams: Role of CO 2 -induced coal softening on injectivity, storage efficiency and caprock deformation: Original Research Article: Modeling of CO 2 sequestration in coal seams

DOE PAGES

Ma, Tianran; Rutqvist, Jonny; Liu, Weiqun; ...

2017-01-30

An effective and safe operation for sequestration of CO 2 in coal seams requires a clear understanding of injection-induced coupled hydromechanical processes such as the evolution of pore pressure, permeability, and induced caprock deformation. In this study, CO 2 injection into coal seams was studied using a coupled flow-deformation model with a new stress-dependent porosity and permeability model that considers CO 2 -induced coal softening. Based on triaxial compression tests of coal samples extracted from the site of the first series of enhanced coalbed methane field tests in China, a softening phenomenon that a substantial (one-order-of-magnitude) decrease of Young's modulusmore » and an increase of Poisson's ratio with adsorbed CO 2 content was observed. Such softening was considered in the numerical simulation through an exponential relation between elastic properties (Young's modulus and Poisson's ratio) and CO 2 pressure considering that CO 2 content is proportional to the CO 2 pressure. Our results of the numerical simulation show that the softening of the coal strongly affects the CO 2 sequestration performance, first by impeding injectivity and stored volume (cumulative injection) during the first week of injection, and thereafter by softening mediated rebound in permeability that tends to increase injectivity and storage over the longer term. A sensitivity study shows that stronger CO 2 -induced coal softening and higher CO 2 injection pressure contribute synergistically to increase a significant increase of CO 2 injectivity and adsorption, but also result in larger caprock deformations and uplift. This study demonstrates the importance of considering the CO 2 -induced softening when analyzing the performance and environmental impact of CO 2 -sequestration operations in unminable coal seams.« less

Modeling of CO 2 sequestration in coal seams: Role of CO 2 -induced coal softening on injectivity, storage efficiency and caprock deformation: Original Research Article: Modeling of CO 2 sequestration in coal seams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Tianran; Rutqvist, Jonny; Liu, Weiqun

An effective and safe operation for sequestration of CO 2 in coal seams requires a clear understanding of injection-induced coupled hydromechanical processes such as the evolution of pore pressure, permeability, and induced caprock deformation. In this study, CO 2 injection into coal seams was studied using a coupled flow-deformation model with a new stress-dependent porosity and permeability model that considers CO 2 -induced coal softening. Based on triaxial compression tests of coal samples extracted from the site of the first series of enhanced coalbed methane field tests in China, a softening phenomenon that a substantial (one-order-of-magnitude) decrease of Young's modulusmore » and an increase of Poisson's ratio with adsorbed CO 2 content was observed. Such softening was considered in the numerical simulation through an exponential relation between elastic properties (Young's modulus and Poisson's ratio) and CO 2 pressure considering that CO 2 content is proportional to the CO 2 pressure. Our results of the numerical simulation show that the softening of the coal strongly affects the CO 2 sequestration performance, first by impeding injectivity and stored volume (cumulative injection) during the first week of injection, and thereafter by softening mediated rebound in permeability that tends to increase injectivity and storage over the longer term. A sensitivity study shows that stronger CO 2 -induced coal softening and higher CO 2 injection pressure contribute synergistically to increase a significant increase of CO 2 injectivity and adsorption, but also result in larger caprock deformations and uplift. This study demonstrates the importance of considering the CO 2 -induced softening when analyzing the performance and environmental impact of CO 2 -sequestration operations in unminable coal seams.« less

CO2 sequestration in two mediterranean dune areas subjected to a different level of anthropogenic disturbance

NASA Astrophysics Data System (ADS)

Bonito, Andrea; Ricotta, Carlo; Iberite, Mauro; Gratani, Loretta; Varone, Laura

2017-09-01

Coastal sand dunes are among the most threatened habitats, especially in the Mediterranean Basin, where the high levels of human pressure impair the presence of plant species, putting at risk the maintenance of the ecosystem services, such as CO2 sequestration provided by these habitats. The aim of this study was to analyze how disturbance-induced changes in plant species abundance patterns account for variations in annual CO2 sequestration flow (CS) of Mediterranean sand dune areas. Two sites characterized by a high (site HAD) and a lower (site LAD) anthropogenic disturbance level were selected. At both sites, plant species number, cover, height and CS based on net photosynthesis measurements were sampled. At the plant species level, our results highlighted that Ammophila arenaria and Pancratium maritimum, had a key role in CS. Moreover, the results revealed a patchy species assemblage in both sites. In particular, HAD was characterized by a higher extension of the anthropogenic aphytoic zone (64% of the total transect length) than LAD. In spite of the observed differences in plant species composition, there were not significant differences between HAD and LAD in structural and functional traits, such as plant height and net photosynthesis. As a consequence, HAD and LAD had a similar CS (443 and 421 Mg CO2 ha-1 y-1, respectively). From a monetary point of view, our estimates based on the social costs of carbon revealed that the flow of sequestered CO2 valued on an average 3181 ± 114 ha-1 year-1 (mean value for the two sites). However, considering also the value of the CO2 negative flow related to loss of vegetated area, the annual net benefit arising from CO2 sequestration amounted to 1641 and 1772 for HAD and LAD, respectively. Overall, the results highlighted the importance to maximize the efforts to preserve dune habitats by applying an effective management policy, which could allow maintaining also a regulatory ecosystem service such as CO2 sequestration.

Accounting for Organic Carbon Change in Deep Soil Altered Carbon Sequestration Efficiency

NASA Astrophysics Data System (ADS)

Li, J.; Liang, F.; Xu, M.; Huang, S.

2017-12-01

Study on soil organic carbon (SOC) sequestration under fertilization practices in croplands lacks information of soil C change at depth lower than plow layer (i.e. 20 30-cm). By synthesizing long-term datasets of fertilization experiments in four typical Chinese croplands representing black soil at Gongzhuling(GZL), aquatic Chao soil at Zhengzhou(ZZ), red soil at Qiyang(QY) and purple soil at Chongqing(CQ) city, we calculated changes in SOC storage relative to initial condition (ΔSOC) in 0-20cm and 0-60cm, organic C inputs (OC) from the stubble, roots and manure amendment, and C sequestration efficiency (CSE: the ratio of ΔSOC over OC) in 0-20cm and 0-60cm. The fertilization treatments include cropping with no fertilization (CK), chemical nitrogen, phosphorus and potassium fertilizers (NPK) and combined chemical fertilizers and manure (NPKM). Results showed SOC storage generally decreased with soil depth (i.e. 0-20 > 20-40, 40-60 cm) and increased with fertilizations (i.e. initial < CK < NPK < NPKM). The annual OC input to soil remained relatively stable and manure input was the primary source of OC input under NPKM treatment. Assuming all OC input remained at 0-60cm and 50 90% distributed at 0-20cm, our results supported that CSE at 0-60cm was consistently larger than that at 0-20cm under NPK and NPKM at GZL (p-value<0.05), but significantly lower under NPK at ZZ and QY (p-value<0.05). These results demonstrated that under long-term fertilizations, soil at depth (>20cm) can act as important soil carbon sinks in intrinsically high fertility soils (i.e. black soil) but less likely at poor fertility soil (i.e. aquatic Chao soil). It thus informs the need to account for C change in deep soils for estimating soil C sequestration capacity particularly with indigenously fertile cropland soils.

HSPB8 and BAG3 cooperate to promote spatial sequestration of ubiquitinated proteins and coordinate the cellular adaptive response to proteasome insufficiency.

PubMed

Guilbert, Solenn M; Lambert, Herman; Rodrigue, Marc-Antoine; Fuchs, Margit; Landry, Jacques; Lavoie, Josée N

2018-02-05

BCL2-associated athanogene (BAG)-3 is viewed as a platform that would physically and functionally link distinct classes of molecular chaperones of the heat shock protein (HSP) family for the stabilization and clearance of damaged proteins. In this study, we show that HSPB8, a member of the small heat shock protein subfamily, cooperates with BAG3 to coordinate the sequestration of harmful proteins and the cellular adaptive response upon proteasome inhibition. Silencing of HSPB8, like depletion of BAG3, inhibited targeting of ubiquitinated proteins to the juxtanuclear aggresome, a mammalian system of spatial quality control. However, aggresome targeting was restored in BAG3-depleted cells by a mutant BAG3 defective in HSPB8 binding, uncoupling HSPB8 function from its binding to BAG3. Depletion of HSPB8 impaired formation of ubiquitinated microaggregates in an early phase and interfered with accurate modifications of the stress sensor p62/sequestosome (SQSTM)-1. This impairment correlated with decreased coupling of BAG3 to p62/SQSTM1 in response to stress, hindering Kelch-like ECH-associated protein (KEAP)-1 sequestration and stabilization of nuclear factor E2-related factor (Nrf)-2, an important arm of the antioxidant defense. Notably, the myopathy-associated mutation of BAG3 (P209L), which lies within the HSPB8-binding motif, deregulated the association between BAG3 and p62/SQSTM1 and the KEAP1-Nrf2 signaling axis. Together, our findings support a so-far-unrecognized role for the HSPB8-BAG3 connection in mounting of an efficient stress response, which may be involved in BAG3-related human diseases.-Guilbert, S. M., Lambert, H., Rodrigue, M.-A., Fuchs, M., Landry, J., Lavoie, J. N. HSPB8 and BAG3 cooperate to promote spatial sequestration of ubiquitinated proteins and coordinate the cellular adaptive response to proteasome insufficiency.

Basin-Scale Hydrologic Impacts of CO2 Storage: Regulatory and Capacity Implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Birkholzer, J.T.; Zhou, Q.

Industrial-scale injection of CO{sub 2} into saline sedimentary basins will cause large-scale fluid pressurization and migration of native brines, which may affect valuable groundwater resources overlying the deep sequestration reservoirs. In this paper, we discuss how such basin-scale hydrologic impacts can (1) affect regulation of CO{sub 2} storage projects and (2) may reduce current storage capacity estimates. Our assessment arises from a hypothetical future carbon sequestration scenario in the Illinois Basin, which involves twenty individual CO{sub 2} storage projects in a core injection area suitable for long-term storage. Each project is assumed to inject five million tonnes of CO{sub 2}more » per year for 50 years. A regional-scale three-dimensional simulation model was developed for the Illinois Basin that captures both the local-scale CO{sub 2}-brine flow processes and the large-scale groundwater flow patterns in response to CO{sub 2} storage. The far-field pressure buildup predicted for this selected sequestration scenario suggests that (1) the area that needs to be characterized in a permitting process may comprise a very large region within the basin if reservoir pressurization is considered, and (2) permits cannot be granted on a single-site basis alone because the near- and far-field hydrologic response may be affected by interference between individual sites. Our results also support recent studies in that environmental concerns related to near-field and far-field pressure buildup may be a limiting factor on CO{sub 2} storage capacity. In other words, estimates of storage capacity, if solely based on the effective pore volume available for safe trapping of CO{sub 2}, may have to be revised based on assessments of pressure perturbations and their potential impact on caprock integrity and groundwater resources, respectively. We finally discuss some of the challenges in making reliable predictions of large-scale hydrologic impacts related to CO{sub 2} sequestration projects.« less

Characterization of Most Promising Sequestration Formations in the Rocky Mountain Region (RMCCS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

McPherson, Brian; Matthews, Vince

2013-09-30

The primary objective of the “Characterization of Most Promising Carbon Capture and Sequestration Formations in the Central Rocky Mountain Region” project, or RMCCS project, is to characterize the storage potential of the most promising geologic sequestration formations within the southwestern U.S. and the Central Rocky Mountain region in particular. The approach included an analysis of geologic sequestration formations under the Craig Power Station in northwestern Colorado, and application or extrapolation of those local-scale results to the broader region. A ten-step protocol for geologic carbon storage site characterization was a primary outcome of this project.

A database and probabilistic assessment methodology for carbon dioxide enhanced oil recovery and associated carbon dioxide retention in the United States

USGS Publications Warehouse

Warwick, Peter D.; Verma, Mahendra K.; Attanasi, Emil; Olea, Ricardo A.; Blondes, Madalyn S.; Freeman, Philip; Brennan, Sean T.; Merrill, Matthew; Jahediesfanjani, Hossein; Roueche, Jacqueline; Lohr, Celeste D.

2017-01-01

The U.S. Geological Survey (USGS) has developed an assessment methodology for estimating the potential incremental technically recoverable oil resources resulting from carbon dioxide-enhanced oil recovery (CO2-EOR) in reservoirs with appropriate depth, pressure, and oil composition. The methodology also includes a procedure for estimating the CO2 that remains in the reservoir after the CO2-EOR process is complete. The methodology relies on a reservoir-level database that incorporates commercially available geologic and engineering data. The mathematical calculations of this assessment methodology were tested and produced realistic results for the Permian Basin Horseshoe Atoll, Upper Pennsylvanian-Wolfcampian Play (Texas, USA). The USGS plans to use the new methodology to conduct an assessment of technically recoverable hydrocarbons and associated CO2 sequestration resulting from CO2-EOR in the United States.

Implication of soil C sequestration on sustainable agriculture and environment.

PubMed

Mondini, C; Sequi, P

2008-01-01

Soil organic matter (SOM) is the largest C stock of the continental biosphere with 1550Pg. The size of C reservoir in the soil and environmental concerns on climate change have recently attracted the attention of scientist and politicians on C sequestration as an effective strategy to tackle greenhouse gas (GHG) emissions. It has been estimated that the potential for C storage in world cropland is relevant (about 0.6-1.2PgCy(-1)). However, there are several constraints of C sequestration that raise concern about its effectiveness as a strategy to offset climate change. C sequestration is finite in quantity and time, reversible, and can be further decreased by socio-economic restrictions. Given these limitations, C sequestration can play only a minor role in the reduction of emissions (2-5% of total GHG emission under the highest emission scenarios). Yet, C sequestration is still attractive for two main reasons: it is likely to be particularly effective in reducing atmospheric CO2 levels in the first 20-30yr of its implementation and presents ancillary benefits for environment and sustainability that make it a real win-win strategy. These beneficial implications are discussed in this paper with emphasis on the need of C sequestration not only to offset climatic changes, but also for the equilibria of the environment and for the sustainability of agriculture and of entire human society.

Biotic and abiotic effects on CO2 sequestration during microbially-induced calcium carbonate precipitation.

PubMed

Okyay, Tugba Onal; Rodrigues, Debora F

2015-03-01

In this study, CO2 sequestration was investigated through the microbially-induced calcium carbonate precipitation (MICP) process with isolates obtained from a cave called 'Cave Without A Name' (Boerne, TX, USA) and the Pamukkale travertines (Denizli, Turkey). The majority of the bacterial isolates obtained from these habitats belonged to the genera Sporosarcina, Brevundimonas, Sphingobacterium and Acinetobacter. The isolates were investigated for their capability to precipitate calcium carbonate and sequester CO2. Biotic and abiotic effects of CO2 sequestration during MICP were also investigated. In the biotic effect, we observed that the rate and concentration of CO2 sequestered was dependent on the species or strains. The main abiotic factors affecting CO2 sequestration during MICP were the pH and medium components. The increase in pH led to enhanced CO2 sequestration by the growth medium. The growth medium components, on the other hand, were shown to affect both the urease activity and CO2 sequestration. Through the Plackett-Burman experimental design, the most important growth medium component involved in CO2 sequestration was determined to be urea. The optimized medium composition by the Plackett-Burman design for each isolate led to a statistically significant increase, of up to 148.9%, in CO2 uptake through calcification mechanisms. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Teacher and Classroom Characteristics and Their Relations to Mathematics Achievement of the Students in the TIMSS

ERIC Educational Resources Information Center

Akyuz, Gozde; Berberoglu, Giray

2010-01-01

Background: Teacher-related factors such as gender, experience, conceptions related to mathematics, instructional practices have effects with various magnitudes on students' mathematics achievement. Classroom related factors such as class size, class climate and limitations to teaching and their relation to mathematics achievement have also been…

Efficiency of incentives to jointly increase carbon sequestration and species conservation on a landscape

Treesearch

Erik Nelson; Stephen Polasky; David J. Lewis; Andrew J. Plantinga; Eric Lonsdorf; Denis White; David Bael; Joshua Lawler

2008-01-01

We develop an integrated model to predict private land-use decisions in response to policy incentives designed to increase the provision of carbon sequestration and species conservation across heterogeneous landscapes. Using data from the Willamette Basin, Oregon, we compare the provision of carbon sequestration and species conservation under five simple policies that...

Today's PTA Advocate: Speak Up to Stop Sequestration

ERIC Educational Resources Information Center

Chevalier, Jacque

2012-01-01

The word sequestration has been in the news lately when talking about the federal budget. Sequestration refers to across-the-board cuts, and depending on where one lives and the amount of federal aid one's community receives, those cuts could amount to as much as 17 percent. That spells bad news for schools unless parents, educators, and other…

Quantifying carbon sequestration in forest plantations by modeling the dynamics of above and below ground carbon pools

Treesearch

Chris A. Maier; Kurt H. Johnsen

2010-01-01

Intensive pine plantation management may provide opportunities to increase carbon sequestration in the Southeastern United States. Developing management options that increase fiber production and soil carbon sequestration require an understanding of the biological and edaphic processes that control soil carbon turnover. Belowground carbon resides primarily in three...

Soil carbon sequestration potential in semi-arid grasslands in the conservation reserve program

USDA-ARS?s Scientific Manuscript database

The Conservation Reserve Program (CRP) in the USA plays a major role in carbon (C) sequestration to help mitigate rising CO2 levels and climate change. The Southern High Plains (SHP) region contains N900.000 ha enrolled in CRP, but a regionally specific C sequestration rate has not been studied, and...

Using silviculture to influence carbon sequestration in southern Appalachian spruce-fir forests

Treesearch

Patrick T. Moore; R. Justin DeRose; James N. Long; Helga van Miegroet

2012-01-01

Enhancement of forest growth through silvicultural modification of stand density is one strategy for increasing carbon (C) sequestration. Using the Fire and Fuels Extension of the Forest Vegetation Simulator, the effects of even-aged, uneven-aged and no-action management scenarios on C sequestration in a southern Appalachian red spruce-Fraser fir forest were modeled....

A drawdown solution for constant-flux pumping in a confined anticline aquifer

NASA Astrophysics Data System (ADS)

Chen, Yen-Ju; Yeh, Hund-Der; Kuo, Chia-Chen

2011-08-01

SummaryAn anticline, known as a convex-upward fold in layers of rock, commonly is formed during lateral compression, which may be elected as a potential site for carbon sequestration. A mathematical model is developed in this study for describing the steady-state drawdown distribution in an anticline aquifer in response to the constant-flux pumping. The topographical shape of the anticline is mimicked by three successive blocks. The solution is obtained by applying the infinite Fourier transform and the finite Fourier cosine transform in each blocks and acquiring the hydraulic continuities between the blocks. Simulated results reveal that the introduction of a thin-limbs or narrow-ridged anticline would produce a much greater head drop in the ridge zone. For a well of constant pumping rate, the dimensionless drawdown around the well increases with decreasing well screen length or/and aquifer anisotropy ratio. An examination of the effect of well location on the drawdown reveals that the partially penetrating well located at the top-middle of the ridge zone produces the largest drawdown. The simulation of the flow in an anticline aquifer based on MODFLOW results in slightly smaller drawdown values in most regions when compared with those predicted by the present solution. The present solution can also be used to simulate the flow in a slab-shaped aquifer or a hillslope aquifer. It can be applied to determine the aquifer parameters if coupled with an optimization scheme and to provide the basis for selecting a potential site for carbon sequestration in the future as well.

Self-concept mediates the relation between achievement and emotions in mathematics.

PubMed

Van der Beek, Jojanneke P J; Van der Ven, Sanne H G; Kroesbergen, Evelyn H; Leseman, Paul P M

2017-09-01

Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions. The aims were (1) to investigate the mediating role of mathematical self-concept in the relation between mathematics achievement and the achievement emotions of enjoyment and anxiety in a comprehensive model, and (2) to test possible differences in this mediating role between low-, average-, and high-achieving students. Participants were ninth-grade students (n = 1,014) from eight secondary schools in the Netherlands. Through an online survey including mathematical problems, students were asked to indicate their levels of mathematics enjoyment, anxiety, and self-concept. Structural equation modelling was used to test the mediating role of self-concept in the relation between mathematics achievement and emotions. Multigroup analyses were performed to compare these relations across the three achievement groups. Results confirmed full mediation of the relation between mathematics achievement and emotions by mathematical self-concept. Furthermore, we found higher self-concepts, more enjoyment and less math anxiety in high-achieving students compared to their average and low-achieving peers. No differences across these achievement groups were found in the relations in the mediational model. Mathematical self-concept plays a pivotal role in students' appraisal of mathematics. Mathematics achievement is only one factor explaining students' self-concept. Likely also classroom instruction and teachers' feedback strategies help to shape students' self-concept. © 2017 The British Psychological Society.

The United States Department of Energy's Regional Carbon Sequestration Partnerships program: a collaborative approach to carbon management.

PubMed

Litynski, John T; Klara, Scott M; McIlvried, Howard G; Srivastava, Rameshwar D

2006-01-01

This paper reviews the Regional Carbon Sequestration Partnerships (RCSP) concept, which is a first attempt to bring the U.S. Department of Energy's (DOE) carbon sequestration program activities into the "real world" by using a geographically-disposed-system type approach for the U.S. Each regional partnership is unique and covers a unique section of the U.S. and is tasked with determining how the research and development activities of DOE's carbon sequestration program can best be implemented in their region of the country. Although there is no universal agreement on the cause, it is generally understood that global warming is occurring, and many climate scientists believe that this is due, in part, to the buildup of carbon dioxide (CO(2)) in the atmosphere. This is evident from the finding presented in the National Academy of Science Report to the President on Climate Change which stated "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise. Temperatures are, in fact, rising. The changes observed over the last several decades are likely mostly due to human activities, ...". In the United States, emissions of CO(2) originate mainly from the combustion of fossil fuels for energy production, transportation, and other industrial processes. Roughly one third of U.S. anthropogenic CO(2) emissions come from power plants. Reduction of CO(2) emissions through sequestration of carbon either in geologic formations or in terrestrial ecosystems can be part of the solution to the problem of global warming. However, a number of steps must be accomplished before sequestration can become a reality. Cost effective capture and separation technology must be developed, tested, and demonstrated; a database of potential sequestration sites must be established; and techniques must be developed to measure, monitor, and verify the sequestered CO(2). Geographical differences in fossil fuel use, the industries present, and potential sequestration sinks across the United States dictate the use of a regional approach to address the sequestration of CO(2). To accommodate these differences, the DOE has created a nationwide network of seven Regional Carbon Sequestration Partnerships (RCSP) to help determine and implement the carbon sequestration technologies, infrastructure, and regulations most appropriate to promote CO(2) sequestration in different regions of the nation. These partnerships currently represent 40 states, three Indian Nations, four Canadian Provinces, and over 200 organizations, including academic institutions, research institutions, coal companies, utilities, equipment manufacturers, forestry and agricultural representatives, state and local governments, non-governmental organizations, and national laboratories. These partnerships are dedicated to developing the necessary infrastructure and validating the carbon sequestration technologies that have emerged from DOE's core R&D and other programs to mitigate emissions of CO(2), a potent greenhouse gas. The partnerships provide a critical link to DOE's plans for FutureGen, a highly efficient and technologically sophisticated coal-fired power plant that will produce both hydrogen and electricity with near-zero emissions. Though limited to the situation in the U.S., the paper describes for the international scientific community the approach being taken by the U.S. to prepare for carbon sequestration, should that become necessary.

Carbon sequestration potential estimates with changes in land use and tillage practice in Ohio, USA

USGS Publications Warehouse

Tan, Z.; Lal, R.

2005-01-01

Soil C sequestration through changes in land use and management is one of the important strategies to mitigate the global greenhouse effect. This study was conducted to estimate C sequestration potential of the top 20 cm depth of soil for two scenarios in Ohio, USA: (1) with reforestation of both current cropland and grassland where SOC pools are less than the baseline SOC pool under current forest; (2) with the adoption of NT on all current cropland. Based on Ohio Soil Survey Characterization Database and long-term experimental data of paired conservation tillage (CT) versus no-till (NT), we specified spatial variations of current SOC pools and C sequestration potentials associated with soil taxa within each major land resource area (MLRA). For scenario I, there would be 4.56 Mha of cropland having an average SOC sequestration capacity of 1.55 kg C m−2 and 0.80 Mha of grassland with that of 1.35 kg C m−2. Of all potential area, 73% are associated with Alfisols and 15% with Mollisols, but the achievable potential could vary significantly with individual MLRAs. Alternately, an average SOC sequestration rate of 62 g C m−2 year−1 was estimated with conversion from CT to NT for cultivated Alfisols, by which a cumulative increase of 71 Tg C resulted from reforestation of cropland could be realized in 25 years. Soils with lower antecedent C contents have higher C sequestration rates. In comparison with the results obtained at the state scale, the estimates of SOC sequestration potentials taxonomically associated with each specific MLRA may be more useful to the formulation of C credit trading programs.

Identification of a Platelet Membrane Glycoprotein as a Falciparum Malaria Sequestration Receptor

NASA Astrophysics Data System (ADS)

Ockenhouse, Christian F.; Tandon, Narendra N.; Magowan, Cathleen; Jamieson, G. A.; Chulay, Jeffrey D.

1989-03-01

Infections with the human malaria parasite Plasmodium falciparum are characterized by sequestration of erythrocytes infected with mature forms of the parasite. Sequestration of infected erythrocytes appears to be critical for survival of the parasite and to mediate immunopathological abnormalities in severe malaria. A leukocyte differentiation antigen (CD36) was previously suggested to have a role in sequestration of malaria-infected erythrocytes. CD36 was purified from platelets, where it is known as GPIV, and was shown to be a receptor for binding of infected erythrocytes. Infected erythrocytes adhered to CD36 immobilized on plastic; purified CD36 exhibited saturable, specific binding to infected erythrocytes; and purified CD36 or antibodies to CD36 inhibited and reversed binding of infected erythrocytes to cultured endothelial cells and melanoma cells in vitro. The portion of the CD36 molecule that reverses cytoadherence may be useful therapeutically for rapid reversal of sequestration in cerebral malaria.

Submicron structures provide preferential spots for carbon and nitrogen sequestration in soils

PubMed Central

Vogel, Cordula; Mueller, Carsten W.; Höschen, Carmen; Buegger, Franz; Heister, Katja; Schulz, Stefanie; Schloter, Michael; Kögel-Knabner, Ingrid

2014-01-01

The sequestration of carbon and nitrogen by clay-sized particles in soils is well established, and clay content or mineral surface area has been used to estimate the sequestration potential of soils. Here, via incubation of a sieved (<2 mm) topsoil with labelled litter, we find that only some of the clay-sized surfaces bind organic matter (OM). Surprisingly, <19% of the visible mineral areas show an OM attachment. OM is preferentially associated with organo-mineral clusters with rough surfaces. By combining nano-scale secondary ion mass spectrometry and isotopic tracing, we distinguish between new labelled and pre-existing OM and show that new OM is preferentially attached to already present organo-mineral clusters. These results, which provide evidence that only a limited proportion of the clay-sized surfaces contribute to OM sequestration, revolutionize our view of carbon sequestration in soils and the widely used carbon saturation estimates. PMID:24399306

A ranking of net national contributions to climate change mitigation through tropical forest conservation.

PubMed

Carrasco, L R; Papworth, S K

2014-12-15

Deforestation in tropical regions causes 15% of global anthropogenic carbon emissions and reduces the mitigation potential of carbon sequestration services. A global market failure occurs as the value of many ecosystem services provided by forests is not recognised by the markets. Identifying the contribution of individual countries to tropical carbon stocks and sequestration might help identify responsibilities and facilitate debate towards the correction of the market failure through international payments for ecosystem services. We compare and rank tropical countries' contributions by estimating carbon sequestration services vs. emissions disservices. The annual value of tropical carbon sequestration services in 2010 from 88 tropical countries was estimated to range from $2.8 to $30.7 billion, using market and social prices of carbon respectively. Democratic Republic of Congo, India and Sudan contribute the highest net carbon sequestration, whereas Brazil, Nigeria and Indonesia are the highest net emitters. Copyright © 2014 Elsevier Ltd. All rights reserved.

On the Relationships between (Relatively) Advanced Mathematical Knowledge and (Relatively) Advanced Problem-Solving Behaviours

ERIC Educational Resources Information Center

Koichu, Boris

2010-01-01

This article discusses an issue of inserting mathematical knowledge within the problem-solving processes. Relatively advanced mathematical knowledge is defined in terms of "three mathematical worlds"; relatively advanced problem-solving behaviours are defined in terms of taxonomies of "proof schemes" and "heuristic behaviours". The relationships…

Deep-ocean ferromanganese crusts and nodules

USGS Publications Warehouse

Hein, James R.; Koschinsky, Andrea

2014-01-01

Ferromanganese crusts and nodules may provide a future resource for a large variety of metals, including many that are essential for emerging high- and green-technology applications. A brief review of nodules and crusts provides a setting for a discussion on the latest (past 10 years) research related to the geochemistry of sequestration of metals from seawater. Special attention is given to cobalt, nickel, titanium, rare earth elements and yttrium, bismuth, platinum, tungsten, tantalum, hafnium, tellurium, molybdenum, niobium, zirconium, and lithium. Sequestration from seawater by sorption, surface oxidation, substitution, and precipitation of discrete phases is discussed. Mechanisms of metal enrichment reflect modes of formation of the crusts and nodules, such as hydrogenetic (from seawater), diagenetic (from porewaters), and mixed diagenetic–hydrogenetic processes.

Restingomyces, a new sequestrate genus from the Brazilian Atlantic rainforest that is phylogenetically related to early-diverging taxa in Trappeaceae (Phallales).

PubMed

Sulzbacher, Marcelo A; Grebenc, Tine; Cabral, Tiara S; Giachini, Admir J; Goto, Bruno T; Smith, Matthew E; Baseia, Iuri G

2016-09-01

Restingomyces reticulatus gen. et sp. nov. is a recently discovered false truffle species from Atlantic "restinga" rainforest in northeastern Brazil. Molecular and morphological characters separate this new sequestrate species from other described taxa in the order Phallales (Phallomycetidae, Basidiomycota). In our phylogenetic analysis based on nuc 28S rDNA and atp6, R. reticulatus forms a sister clade to Trappea darkeri and Phallobata alba, with the three taxa forming the earliest diverging lineage within Phallales. Morphological and molecular data warrant the recognition of the new genus and species, described here, and we also amend the taxonomic description for the family Trappeaceae. © 2016 by The Mycological Society of America.

Assessment on the rates and potentials of soil organic carbon sequestration in agricultural lands in Japan using a process-based model and spatially explicit land-use change inventories - Part 2: Future potentials

NASA Astrophysics Data System (ADS)

Yagasaki, Y.; Shirato, Y.

2014-08-01

Future potentials of the sequestration of soil organic carbon (SOC) in agricultural lands in Japan were estimated using a simulation system we recently developed to simulate SOC stock change at country-scale under varying land-use change, climate, soil, and agricultural practices, in a spatially explicit manner. Simulation was run from 1970 to 2006 with historical inventories, and subsequently to 2020 with future scenarios of agricultural activity comprised of various agricultural policy targets advocated by the Japanese government. Furthermore, the simulation was run subsequently until 2100 while forcing no temporal changes in land-use and agricultural activity to investigate duration and course of SOC stock change at country scale. A scenario with an increased rate of organic carbon input to agricultural fields by intensified crop rotation in combination with the suppression of conversion of agricultural lands to other land-use types was found to have a greater reduction of CO2 emission by enhanced soil carbon sequestration, but only under a circumstance in which the converted agricultural lands will become settlements that were considered to have a relatively lower rate of organic carbon input. The size of relative reduction of CO2 emission in this scenario was comparable to that in another contrasting scenario (business-as-usual scenario of agricultural activity) in which a relatively lower rate of organic matter input to agricultural fields was assumed in combination with an increased rate of conversion of the agricultural fields to unmanaged grasslands through abandonment. Our simulation experiment clearly demonstrated that net-net-based accounting on SOC stock change, defined as the differences between the emissions and removals during the commitment period and the emissions and removals during a previous period (base year or base period of Kyoto Protocol), can be largely influenced by variations in future climate. Whereas baseline-based accounting, defined as differences between the net emissions in the accounting period and the ex ante estimation of net business-as-usual emissions for the same period, has robustness over variations in future climate and effectiveness to factor out some of the direct human-induced effects such as changing land-use and agricultural activity. Factors affecting uncertainties in the estimation of the country-scale potential of SOC sequestration were discussed, especially those related to estimation of the rate of organic carbon input to soils under different land-use types. Our study suggested that, in order to assist decision making of policy on agriculture, land management, and mitigation of global climate change, it is also important to take account of duration and time course of SOC sequestration, supposition on land-use change pattern in future, as well as feasibility of agricultural policy planning.

Geologic Sequestration of CO2: Potential Permeability Changes in Host Formations of the San Juan Basin, New Mexico

NASA Astrophysics Data System (ADS)

Abel, A. P.; McPherson, B.; Lichtner, P.; Bond, G.; Stringer, J.; Grigg, R.

2002-12-01

Terrestrial sequestration through injection into geologic formations is one proposed method for the isolation of anthropogenic CO2 from the atmosphere. A variety of physical and chemical processes are known to occur both during and after geologic CO2 injection, including diagenetic chemical reactions and associated permeability changes. Although it is commonly assumed that CO2 sequestered in this way will ultimately become mineralized, the rates of these changes, including CO2 hydration in brines, are known to be relatively slow. Bond and others (this volume) have developed a biomimetic approach to CO2 sequestration, in which the rate of CO2 hydration is accelerated by the use of a biological catalyst. Together with the hydrated CO2, cations from produced brines may be used to form solid-state carbonate minerals at the earth's surface, or this bicarbonate solution may be reinjected for geologic sequestration. Chemical composition of produced brines will affect both the diagenetic reactions that occur within the host formation, and the precipitation reactions that will occur above ground. In a specific case study of the San Juan Basin, New Mexico, we are cataloging different brines present in that basin. We are using this information to facilitate evaluation of potential applications of the biomimetic process and geologic sequestration. In a separate collaborative study by Grigg and others (this volume), laboratory experiments have been conducted on multiphase CO2 and brine injection and flow through saturated rock cores. We are extending from that study to our specific case study of the San Juan basin, to examine and characterize potential permeability changes associated with accelerated diagenesis due to the presence of high concentrations of CO2 or bicarbonate solutions in situ. We are developing and conducting new laboratory experiments to evaluate relative permeability (to CO2 and brine) of selected strata from the Fruitland Formation and Pictured Cliffs Sandstone. In addition to relative permeability, we are conducting longer-term flow tests reflecting marked permeability changes, and documenting the changes by comparing detailed pre-test measurements of porosity and permeability to post-test measurements. We are using these experimental results to parameterize coupled-flow and reactive-chemistry models of a selected cross-section of the San Juan basin. Our flow and chemistry model is based on the Los Alamos National Laboratory reactive chemistry simulator, TRANS, coupled to the Lawrence Berkeley Laboratory flow simulator, TOUGH2. The purpose of these simulation models is to evaluate potential CO2- and bicarbonate-induced diagenetic changes in permeability and flow at the basin-scale. In addition they will provide useful information in relation to brine extraction. We are also using these calibrated basin models to examine natural diagenesis and permeability evolution associated with changing brine properties and flow conditions over geologic time.

Carbon sequestration in the U.S. forest sector from 1990 to 2010

Treesearch

Peter B. Woodbury; James E. Smith; Linda S. Heath

2007-01-01

Forest inventory data supplemented with data from intensive research sites and models were used to estimate carbon stocks and sequestration rates in U.S. forests, including effects of land use change. Data on the production of wood products and emission from decomposition were used to estimate carbon stocks and sequestration rates in wood products and landfills. From...

New cost estimates for carbon sequestration through afforestation in the United States

Treesearch

Anne Sofie Elburg Nielsen; Andrew J. Plantinga; Ralph J. Alig

2014-01-01

This report provides new cost estimates for carbon sequestration through afforestation in the United States. We extend existing studies of carbon sequestration costs in several important ways, while ensuring the transparency of our approach. We clearly identify all components of our cost estimates so that other researchers can reconstruct our results as well as use our...

Assessing net carbon sequestration on urban and community forests of northern New England, USA

Treesearch

Daolan Zheng; Mark J. Ducey; Linda S. Heath

2013-01-01

Urban and community forests play an important role in the overall carbon budget of the USA. Accurately quantifying carbon sequestration by these forests can provide insight for strategic planning to mitigate greenhouse gas effects on climate change. This study provides a new methodology to estimate net forest carbon sequestration (FCS) in urban and community lands of...

Payments for carbon sequestration to alleviate development pressure in a rapidly urbanizing region

USGS Publications Warehouse

Smith, Jordan W.; Dorning, Monica; Shoemaker, Douglas A.; Méley, Andréanne; Dupey, Lauren; Meentemeyer, Ross K.

2017-01-01

The purpose of this study was to determine individuals' willingness to enroll in voluntary payments for carbon sequestration programs through the use of a discrete choice experiment delivered to forest owners living in the rapidly urbanizing region surrounding Charlotte, North Carolina. We examined forest owners' willingness to enroll in payments for carbon sequestration policies under different levels of financial incentives (annual revenue), different contract lengths, and different program administrators (e.g., private companies versus a state or federal agency). We also examined the influence forest owners' sense of place had on their willingness to enroll in hypothetical programs. Our results showed a high level of ambivalence toward participating in payments for carbon sequestration programs. However, both financial incentives and contract lengths significantly influenced forest owners' intent to enroll. Neither program administration nor forest owners' sense of place influenced intent to enroll. Although our analyses indicated that payments from carbon sequestration programs are not currently competitive with the monetary returns expected from timber harvest or property sales, certain forest owners might see payments for carbon sequestration programs as a viable option for offsetting increasing tax costs as development encroaches and property values rise.

[Greenhouse gas emissions, carbon leakage and net carbon sequestration from afforestation and forest management: A review.

PubMed

Liu, Bo Jie; Lu, Fei; Wang, Xiao Ke; Liu, Wei Wei

2017-02-01

Forests play an important role in climate change mitigation and concentration of CO 2 reduction in the atmosphere. Forest management, especially afforestation and forest protection, could increase carbon stock of forests significantly. Carbon sequestration rate of afforestation ranges from 0.04 to 7.52 t C·hm -2 ·a -1 , while that of forest protection is 0.33-5.20 t C·hm -2 ·a -1 . At the same time, greenhouse gas (GHG) is generated within management boundary due to the production and transportation of the materials consumed in relevant activities of afforestation and forest management. In addition, carbon leakage is also generated outside boundary from activity shifting, market effects and change of environments induced by forest management. In this review, we summarized the definition of emission sources of GHG, monitoring methods, quantity and rate of greenhouse gas emissions within boundary of afforestation and forest management. In addition, types, monitoring methods and quantity of carbon leakage outside boundary of forest management were also analyzed. Based on the reviewed results of carbon sequestration, we introduced greenhouse gas emissions within boundary and carbon leakage, net carbon sequestration as well as the countervailing effects of greenhouse gas emissions and carbon leakage to carbon sequestration. Greenhouse gas emissions within management boundary counteract 0.01%-19.3% of carbon sequestration, and such counteraction could increase to as high as 95% considering carbon leakage. Afforestation and forest management have substantial net carbon sequestration benefits, when only taking direct greenhouse gas emissions within boundary and measurable carbon leakage from activity shifting into consideration. Compared with soil carbon sequestration measures in croplands, afforestation and forest management is more advantageous in net carbon sequestration and has better prospects for application in terms of net mitigation potential. Along with the implementation of the new stage of key ecological stewardship projects in China as well as the concern on carbon benefits brought by projects, it is necessary to make efforts to increase net carbon sequestration via reducing greenhouse gas emissions and carbon leakage. Rational planning before start-up of the projects should be promoted to avoid carbon emissions due to unnecessary consumption of materials and energy. Additionally, strengthening the control and monitoring on greenhouse gas emissions and carbon leakage during the implementation of projects are also advocated.

A Survey of Measurement, Mitigation, and Verification Field Technologies for Carbon Sequestration Geologic Storage

NASA Astrophysics Data System (ADS)

Cohen, K. K.; Klara, S. M.; Srivastava, R. D.

2004-12-01

The U.S. Department of Energy's (U.S. DOE's) Carbon Sequestration Program is developing state-of-the-science technologies for measurement, mitigation, and verification (MM&V) in field operations of geologic sequestration. MM&V of geologic carbon sequestration operations will play an integral role in the pre-injection, injection, and post-injection phases of carbon capture and storage projects to reduce anthropogenic greenhouse gas emissions. Effective MM&V is critical to the success of CO2 storage projects and will be used by operators, regulators, and stakeholders to ensure safe and permanent storage of CO2. In the U.S. DOE's Program, Carbon sequestration MM&V has numerous instrumental roles: Measurement of a site's characteristics and capability for sequestration; Monitoring of the site to ensure the storage integrity; Verification that the CO2 is safely stored; and Protection of ecosystems. Other drivers for MM&V technology development include cost-effectiveness, measurement precision, and frequency of measurements required. As sequestration operations are implemented in the future, it is anticipated that measurements over long time periods and at different scales will be required; this will present a significant challenge. MM&V sequestration technologies generally utilize one of the following approaches: below ground measurements; surface/near-surface measurements; aerial and satellite imagery; and modeling/simulations. Advanced subsurface geophysical technologies will play a primary role for MM&V. It is likely that successful MM&V programs will incorporate multiple technologies including but not limited to: reservoir modeling and simulations; geophysical techniques (a wide variety of seismic methods, microgravity, electrical, and electromagnetic techniques); subsurface fluid movement monitoring methods such as injection of tracers, borehole and wellhead pressure sensors, and tiltmeters; surface/near surface methods such as soil gas monitoring and infrared sensors and; aerial and satellite imagery. This abstract will describe results, similarities, and contrasts for funded studies from the U.S. DOE's Carbon Sequestration Program including examples from the Sleipner North Sea Project, the Canadian Weyburn Field/Dakota Gasification Plant Project, the Frio Formation Texas Project, and Yolo County Bioreactor Landfill Project. The abstract will also address the following: How are the terms ``measurement,'' ``mitigation''and ``verification'' defined in the Program? What is the U.S. DOE's Carbon Sequestration Program Roadmap and what are the Roadmap goals for MM&V? What is the current status of MM&V technologies?

[Regional and global estimates of carbon stocks and carbon sequestration capacity in forest ecosystems: A review].

PubMed

Liu, Wei-wei; Wang, Xiao-ke; Lu, Fei; Ouyang, Zhi-yun

2015-09-01

As a dominant part of terrestrial ecosystems, forest ecosystem plays an important role in absorbing atmospheric CO2 and global climate change mitigation. From the aspects of zonal climate and geographical distribution, the present carbon stocks and carbon sequestration capacity of forest ecosystem were comprehensively examined based on the review of the latest literatures. The influences of land use change on forest carbon sequestration were analyzed, and factors that leading to the uncertainty of carbon sequestration assessment in forest ecosystem were also discussed. It was estimated that the current forest carbon stock was in the range of 652 to 927 Pg C and the carbon sequestration capacity was approximately 4.02 Pg C · a(-1). In terms of zonal climate, the carbon stock and carbon sequestration capacity of tropical forest were the maximum, about 471 Pg C and 1.02-1.3 Pg C · a(-1) respectively; then the carbon stock of boreal forest was about 272 Pg C, while its carbon sequestration capacity was the minimum, approximately 0.5 Pg C · a(-1); for temperate forest, the carbon stock was minimal, around 113 to 159 Pg C and its carbon sequestration capacity was 0.8 Pg C · a(-1). From the aspect of geographical distribution, the carbon stock of forest ecosystem in South America was the largest (187.7-290 Pg C), then followed by European (162.6 Pg C), North America (106.7 Pg C), Africa (98.2 Pg C) and Asia (74.5 Pg C), and Oceania (21.7 Pg C). In addition, carbon sequestration capacity of regional forest ecosystem was summed up as listed below: Tropical South America forest was the maximum (1276 Tg C · a(-1)), then were Tropical Africa (753 Tg C · a(-1)), North America (248 Tg C · a(-1)) and European (239 Tg C · a(-1)), and East Asia (98.8-136.5 Tg C · a(-1)) was minimum. To further reduce the uncertainty in the estimations of the carbon stock and carbon sequestration capacity of forest ecosystem, comprehensive application of long-term observation, inventories, remote sensing and modeling method should be required.

A national look at carbon capture and storage-National carbon sequestration database and geographical information system (NatCarb)

USGS Publications Warehouse

Carr, T.R.; Iqbal, A.; Callaghan, N.; ,; Look, K.; Saving, S.; Nelson, K.

2009-01-01

The US Department of Energy's Regional Carbon Sequestration Partnerships (RCSPs) are responsible for generating geospatial data for the maps displayed in the Carbon Sequestration Atlas of the United States and Canada. Key geospatial data (carbon sources, potential storage sites, transportation, land use, etc.) are required for the Atlas, and for efficient implementation of carbon sequestration on a national and regional scale. The National Carbon Sequestration Database and Geographical Information System (NatCarb) is a relational database and geographic information system (GIS) that integrates carbon storage data generated and maintained by the RCSPs and various other sources. The purpose of NatCarb is to provide a national view of the carbon capture and storage potential in the U.S. and Canada. The digital spatial database allows users to estimate the amount of CO2 emitted by sources (such as power plants, refineries and other fossil-fuel-consuming industries) in relation to geologic formations that can provide safe, secure storage sites over long periods of time. The NatCarb project is working to provide all stakeholders with improved online tools for the display and analysis of CO2 carbon capture and storage data. NatCarb is organizing and enhancing the critical information about CO2 sources and developing the technology needed to access, query, model, analyze, display, and distribute natural resource data related to carbon management. Data are generated, maintained and enhanced locally at the RCSP level, or at specialized data warehouses, and assembled, accessed, and analyzed in real-time through a single geoportal. NatCarb is a functional demonstration of distributed data-management systems that cross the boundaries between institutions and geographic areas. It forms the first step toward a functioning National Carbon Cyberinfrastructure (NCCI). NatCarb provides access to first-order information to evaluate the costs, economic potential and societal issues of CO2 capture and storage, including public perception and regulatory aspects. NatCarb online access has been modified to address the broad needs of a spectrum of users. NatCarb includes not only GIS and database query tools for high-end user, but simplified display for the general public using readily available web tools such as Google Earth???and Google Maps???. Not only is NatCarb connected to all the RCSPs, but data are also pulled from public servers including the U.S. Geological Survey-EROS Data Center and from the Geography Network. Data for major CO2 sources have been obtained from U.S. Environmental Protection Agency (EPA) databases, and data on major coal basins and coalbed methane wells were obtained from the Energy Information Administration (EIA). ?? 2009 Elsevier Ltd. All rights reserved.

A Scale for Measuring Teachers' Mathematics-Related Beliefs: A Validity and Reliability Study

ERIC Educational Resources Information Center

Purnomo,Yoppy Wahyu

2017-01-01

The purpose of this study was to develop and validate a scale of teacher beliefs related to mathematics, namely, beliefs about the nature of mathematics, mathematics teaching, and assessment in mathematics learning. A scale development study was used to achieve it. The draft scale consisted of 54 items in which 16 items related to beliefs about…

The Influence of Seal Properties on Pressure Buildup and Leakage of Carbon Dioxide from Sequestration Reservoirs (Invited)

NASA Astrophysics Data System (ADS)

Benson, S. M.; Chabora, E.

2009-12-01

The transport properties of seals, namely permeability, relative permeability, and capillary pressure control both migration of carbon dioxide and brine through the seal. Only recently has the the importance of brine migration emerged as key issue in the environmental performance of carbon dioxide sequestration projects. In this study we use numerical simulation to show that brine migration through the seal can be either advantageous or deleterious to the environmental performance of a carbon dioxide sequestration project. Brine migration through the seal can lower the pressure buildup in the storage reservoir, thereby reducing the risk of leakage or geomechanical stresses on the seal. On the other hand, if the seal is penetrated by a permeable fault it can lead to focused flow up a fault, which could lead to brine migration into drinking water aquifers. We also show that as the carbon dioxide plume grows, brine flow undergoes a complex evolution from upward flow to downward flows driven by countercurrent migration of carbon dioxide and brine in the seal and capillary pressure gradients at the base of the seal. Finally, we discuss desirable attributes seals, taking into account both carbon dioxide and brine migration through the seal. In particular, identifying seals that provide an effective capillary barrier to block the flow of carbon dioxide while allowing some brine migration through the seal can help to control pressure buildup and allow more efficient utilization of a sequestration reservoir. This could be particularly important in those settings that may be limited by the maximum allowable pressure buildup.

Economics- and policy-driven organic carbon input enhancement dominates soil organic carbon accumulation in Chinese croplands.

PubMed

Zhao, Yongcun; Wang, Meiyan; Hu, Shuijin; Zhang, Xudong; Ouyang, Zhu; Zhang, Ganlin; Huang, Biao; Zhao, Shiwei; Wu, Jinshui; Xie, Deti; Zhu, Bo; Yu, Dongsheng; Pan, Xianzhang; Xu, Shengxiang; Shi, Xuezheng

2018-04-17

China's croplands have experienced drastic changes in management practices, such as fertilization, tillage, and residue treatments, since the 1980s. There is an ongoing debate about the impact of these changes on soil organic carbon (SOC) and its implications. Here we report results from an extensive study that provided direct evidence of cropland SOC sequestration in China. Based on the soil sampling locations recorded by the Second National Soil Survey of China in 1980, we collected 4,060 soil samples in 2011 from 58 counties that represent the typical cropping systems across China. Our results showed that across the country, the average SOC stock in the topsoil (0-20 cm) increased from 28.6 Mg C ha -1 in 1980 to 32.9 Mg C ha -1 in 2011, representing a net increase of 140 kg C ha -1 year -1 However, the SOC change differed among the major agricultural regions: SOC increased in all major agronomic regions except in Northeast China. The SOC sequestration was largely attributed to increased organic inputs driven by economics and policy: while higher root biomass resulting from enhanced crop productivity by chemical fertilizers predominated before 2000, higher residue inputs following the large-scale implementation of crop straw/stover return policy took over thereafter. The SOC change was negatively related to N inputs in East China, suggesting that the excessive N inputs, plus the shallowness of plow layers, may constrain the future C sequestration in Chinese croplands. Our results indicate that cropland SOC sequestration can be achieved through effectively manipulating economic and policy incentives to farmers.

Soil organic carbon sequestration in cotton production systems of the southeastern United States: a review.

PubMed

Causarano, H J; Franzluebbers, A J; Reeves, D W; Shaw, J N

2006-01-01

Past agricultural management practices have contributed to the loss of soil organic carbon (SOC) and emission of greenhouse gases (e.g., carbon dioxide and nitrous oxide). Fortunately, however, conservation-oriented agricultural management systems can be, and have been, developed to sequester SOC, improve soil quality, and increase crop productivity. Our objectives were to (i) review literature related to SOC sequestration in cotton (Gossypium hirsutum L.) production systems, (ii) recommend best management practices to sequester SOC, and (iii) outline the current political scenario and future probabilities for cotton producers to benefit from SOC sequestration. From a review of 20 studies in the region, SOC increased with no tillage compared with conventional tillage by 0.48 +/- 0.56 Mg C ha(-1) yr(-1) (H(0): no change, p < 0.001). More diverse rotations of cotton with high-residue-producing crops such as corn (Zea mays L.) and small grains would sequester greater quantities of SOC than continuous cotton. No-tillage cropping with a cover crop sequestered 0.67 +/- 0.63 Mg C ha(-1) yr(-1), while that of no-tillage cropping without a cover crop sequestered 0.34 +/- 47 Mg C ha(-1) yr(-1) (mean comparison, p = 0.04). Current government incentive programs recommend agricultural practices that would contribute to SOC sequestration. Participation in the Conservation Security Program could lead to government payments of up to Dollars 20 ha(-1). Current open-market trading of C credits would appear to yield less than Dollars 3 ha(-1), although prices would greatly increase should a government policy to limit greenhouse gas emissions be mandated.

[Deposition and burial of organic carbon in coastal salt marsh: research progress].

PubMed

Cao, Lei; Song, Jin-Ming; Li, Xue-Gang; Yuan, Hua-Mao; Li, Ning; Duan, Li-Qin

2013-07-01

Coastal salt marsh has higher potential of carbon sequestration, playing an important role in mitigating global warming, while coastal saline soil is the largest organic carbon pool in the coastal salt marsh carbon budget. To study the carbon deposition and burial in this soil is of significance for clearly understanding the carbon budget of coastal salt marsh. This paper summarized the research progress on the deposition and burial of organic carbon in coastal salt marsh from the aspects of the sources of coastal salt marsh soil organic carbon, soil organic carbon storage and deposition rate, burial mechanisms of soil organic carbon, and the relationships between the carbon sequestration in coastal salt marsh and the global climate change. Some suggestions for the future related researches were put forward: 1) to further study the underlying factors that control the variability of carbon storage in coastal salt marsh, 2) to standardize the methods for measuring the carbon storage and the deposition and burial rates of organic carbon in coastal salt marsh, 3) to quantify the lateral exchange of carbon flux between coastal salt marsh and adjacent ecosystems under the effects of tide, and 4) to approach whether the effects of global warming and the increased productivity could compensate for the increase of the organic carbon decomposition rate resulted from sediment respiration. To make clear the driving factors determining the variability of carbon sequestration rate and how the organic carbon storage is affected by climate change and anthropogenic activities would be helpful to improve the carbon sequestration capacity of coastal salt marshes in China.

[Infectious complications after surgical splenectomy in children with sickle cell anemia disease].

PubMed

Monaco Junior, Cypriano Petrus; Fonseca, Patricia Belintani Blum; Braga, Josefina Aparecida Pellegrini

2015-01-01

To evaluate the frequency of infectious complications in children with sickle cell disease (SCD) after surgical splenectomy for acute splenic sequestration crisis. Retrospective cohort of children with SCD who were born after 2002 and were regularly monitored until July 2013. Patients were divided into two groups: cases (children with SCD who underwent surgical splenectomy after an episode of splenic sequestration) and controls (children with SCD who did not have splenic sequestration and surgical procedures), in order to compare the frequency of invasive infections (sepsis, meningitis, bacteremia with positive blood cultures, acute chest syndrome and/or pneumonia) by data collected from medical records. Data were analyzed by descriptive statistical analysis. 44 patients were included in the case group. The mean age at the time of splenectomy was 2.6 years (1-6.9 years) and the mean postoperative length of follow-up was 6.1 years (3.8-9.9 years). The control group consisted of 69 patients with a mean age at the initial follow-up visit of 5.6 months (1-49 months) and a mean length of follow-up of 7.2 years (4-10.3 years). All children received pneumococcal conjugate vaccine. No significant difference was observed between groups in relation to infections during the follow-up. Surgical splenectomy in children with sickle cell disease that had splenic sequestration did not affect the frequency of infectious complications during 6 years of clinical follow-up. Copyright © 2015 Associação de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

Fever of unclear origin and cytopenia because of acute splenic sequestration in a young immunocompetent carrier of beta-globin mutation for Hb Valletta.

PubMed

Parrinello, Gaspare; Torres, Daniele; Paterna, Salvatore; Di Pasquale, Pietro; Licata, Giuseppe

2008-12-01

Fever of unclear origin is a clinical challenge in medical practice. Infectious diseases, neoplasms, and collagen vascular illnesses are its main causes in adults and children. Acute splenic sequestration crises, a known potentially fatal complication of sickle cell disease and sickle beta-thalassemia, are uncommon in beta-heterozygosis. We describe a case of prolonged recurrent episodes of fever with spontaneous resolution, commencing at age 10 in a 15-year-old boy with a history of hypochromic microcytic anemia attributed to a thalassemic trait. He was admitted twice to our university hospital for continuous-remittent fever with a pruritic, macular evanescent Still's skin rash, severe splenomegaly, leucopenia, thrombocytopenia, and sudden aggravation of anemia. Infectious, rheumatologic, autoimmune, and hematologic illnesses were excluded. A genetic-based study revealed heterozygosis of the beta-globin gene for a A>C (Thr>Pro) substitution at position 87 called Hemoglobin Valletta (alpha 2 beta 2 87 PRO) with a C>G transition in homozygosis in beta-globin intronic polymorphism intervening sequence 2 at nucleotide 745. After a follow-up period of 1 year without treatment, the young patient remains apyretic and in good general clinical health with persistent microcythemia and hepatosplenomegaly. Acute splenic sequestration crisis and related cytopenia may be an unusual complication of fever of unclear origin in a beta-thalassemic carrier of a Hemoglobin Valletta mutation and polymorphism in homozygosis of intervening sequence 2 at nucleotide 745. This hemoglobinopathy may predispose to a clinical phenotype of minor or intermediate thalassemia and, during a febrile illness, to hemoglobin instability and splenic sequestration.

Sequestration of flue gas CO₂ by direct gas-solid carbonation of air pollution control system residues.

PubMed

Tian, Sicong; Jiang, Jianguo

2012-12-18

Direct gas-solid carbonation reactions of residues from an air pollution control system (APCr) were conducted using different combinations of simulated flue gas to study the impact on CO₂ sequestration. X-ray diffraction analysis of APCr determined the existence of CaClOH, whose maximum theoretical CO₂ sequestration potential of 58.13 g CO₂/kg APCr was calculated by the reference intensity ratio method. The reaction mechanism obeyed a model of a fast kinetics-controlled process followed by a slow product layer diffusion-controlled process. Temperature is the key factor in direct gas-solid carbonation and had a notable influence on both the carbonation conversion and the CO₂ sequestration rate. The optimal CO₂ sequestrating temperature of 395 °C was easily obtained for APCr using a continuous heating experiment. CO₂ content in the flue gas had a definite influence on the CO₂ sequestration rate of the kinetics-controlled process, but almost no influence on the final carbonation conversion. Typical concentrations of SO₂ in the flue gas could not only accelerate the carbonation reaction rate of the product layer diffusion-controlled process, but also could improve the final carbonation conversion. Maximum carbonation conversions of between 68.6% and 77.1% were achieved in a typical flue gas. Features of rapid CO₂ sequestration rate, strong impurities resistance, and high capture conversion for direct gas-solid carbonation were proved in this study, which presents a theoretical foundation for the applied use of this encouraging technology on carbon capture and storage.

Effect of rainfall seasonality on carbon storage in tropical dry ecosystems

NASA Astrophysics Data System (ADS)

Rohr, Tyler; Manzoni, Stefano; Feng, Xue; Menezes, Rômulo S. C.; Porporato, Amilcare

2013-07-01

seasonally dry conditions are typical of large areas of the tropics, their biogeochemical responses to seasonal rainfall and soil carbon (C) sequestration potential are not well characterized. Seasonal moisture availability positively affects both productivity and soil respiration, resulting in a delicate balance between C deposition as litterfall and C loss through heterotrophic respiration. To understand how rainfall seasonality (i.e., duration of the wet season and rainfall distribution) affects this balance and to provide estimates of long-term C sequestration, we develop a minimal model linking the seasonal behavior of the ensemble soil moisture, plant productivity, related C inputs through litterfall, and soil C dynamics. A drought-deciduous caatinga ecosystem in northeastern Brazil is used as a case study to parameterize the model. When extended to different patterns of rainfall seasonality, the results indicate that for fixed annual rainfall, both plant productivity and soil C sequestration potential are largely, and nonlinearly, dependent on wet season duration. Moreover, total annual rainfall is a critical driver of this relationship, leading at times to distinct optima in both production and C storage. These theoretical predictions are discussed in the context of parameter uncertainties and possible changes in rainfall regimes in tropical dry ecosystems.

Estimating the CO2 sequestration potential of depleted and fractured shale formations using CH4 production rates

NASA Astrophysics Data System (ADS)

Clarens, A. F.; Tao, Z.

2013-12-01

Oil and gas production from hydraulically fractured shale formations is an abundant new source of domestically available energy for the United States. It will also result in significant CO2 emissions with important climate implications. Several studies have suggested that fractured shale formations could be used to permanently store CO2 once they are depleted of hydrocarbons. Many of the largest shale formations being developed in the United States have temperature and pressure profiles that are similar to those of saline aquifers being widely studied for geologic carbon sequestration. Here a modeling framework was developed that can be used to estimate the sequestration capacity for a shale formation based on historical CH4 production. The model is applied to those portions of the Marcellus formation found in Pennsylvania because reliable data on well production is readily available for this state. Production data from over 300 wells was compiled and used to estimate historical production and to extrapolate projected production. In shales, much of the CO2 would be sorbed to the pore and fracture surface and so this model considers sorption kinetics as well as total sorption capacity. The results suggest that shale formations could represent a significant repository for geologic carbon sequestration. The Marcellus shale in Pennsylvania alone could store between 10.4 and 18.4 Gigatonnes of CO2 between now and 2030. This would be over 50% of total annual US CO2 emissions from stationary sources. The mass transfer and sorption kinetics results indicate that CO2 injection proceeds several times faster than CH4 production. Model estimates were most sensitive to the permeability of the formation and assumptions about the ultimate ratio of adsorbed CH4 to CO2. CH4 production is a useful basis for calculating sequestration capacity because gas mass transfer out of the formation will be impacted by the same factors (e.g., temperature, pressure, and moisture content) influencing gas injection. The differences between horizontal and non-horizontal wells were taken into account to understand how well structure would influence gas transport kinetics. It was assumed that only the sorbed CO2 would stay in the formation over time. These estimates for sequestration capacity suggest that the approach merits further study to understand the viability of this approach and opportunities to leverage existing infrastructure. Other synergies could exist in terms of monitoring. Related impacts associated with induced seismicity and leakage would need to be explored to understand the full potential of this approach. The sequestration capacity estimated using this model supports continued exploration into this pathway for producing carbon neutral energy.

A review on soil carbon accumulation due to the management change of major Brazilian agricultural activities.

PubMed

La Scala, N; De Figueiredo, E B; Panosso, A R

2012-08-01

Agricultural areas deal with enormous CO2 intake fluxes offering an opportunity for greenhouse effect mitigation. In this work we studied the potential of soil carbon sequestration due to the management conversion in major agricultural activities in Brazil. Data from several studies indicate that in soybean/maize, and related rotation systems, a significant soil carbon sequestration was observed over the year of conversion from conventional to no-till practices, with a mean rate of 0.41 Mg C ha(-1) year(-1). The same effect was observed in sugarcane fields, but with a much higher accumulation of carbon in soil stocks, when sugarcane fields are converted from burned to mechanised based harvest, where large amounts of sugarcane residues remain on the soil surface (1.8 Mg C ha(-1) year(-1)). The higher sequestration potential of sugarcane crops, when compared to the others, has a direct relation to the primary production of this crop. Nevertheless, much of this mitigation potential of soil carbon accumulation in sugarcane fields is lost once areas are reformed, or intensive tillage is applied. Pasture lands have shown soil carbon depletion once natural areas are converted to livestock use, while integration of those areas with agriculture use has shown an improvement in soil carbon stocks. Those works have shown that the main crop systems of Brazil have a huge mitigation potential, especially in soil carbon form, being an opportunity for future mitigation strategies.

Remediation of degraded arable steppe soils in Moldova using vetch as green manure

NASA Astrophysics Data System (ADS)

Wiesmeier, M.; Lungu, M.; Hübner, R.; Cerbari, V.

2015-01-01

In the Republic of Moldova, non-sustainable arable farming led to severe degradation and erosion of fertile steppe soils (Chernozems). As a result, the Chernozems lost about 40% of their initial amounts of soil organic carbon (SOC). Aim of this study was to remediate degraded arable soils and promote carbon sequestration by implementation of cover cropping and green manuring in Moldova. Thereby, the suitability of the legume hairy vetch (Vicia sativa) as cover crop under the dry, continental climate of Moldova was examined. At two experimental sites, the effect of cover cropping on chemical and physical soil properties as well as on yields of subsequent main crops was determined. The results showed a significant increase of SOC after incorporation of hairy vetch due to a high above- and belowground biomass production that was related with a high input of carbon and nitrogen. A calculation of SOC stocks based on equivalent soil masses revealed a sequestration of around 3 t C ha-1 yr-1 as a result of hairy vetch cover cropping. The buildup of SOC was associated with an improvement of the soil structure as indicated by a distinct decrease of bulk density and a relative increase of macroaggregates at the expense of microaggregates and clods. As a result, yields of subsequent main crops increased by around 20%. Our results indicated that hairy vetch is a promising cover crop to remediate degraded steppe soils, control soil erosion and sequestrate substantial amounts of atmospheric C in arable soils of Moldova.

Uncertainty In Greenhouse Gas Emissions On Carbon Sequestration In Coastal and Freshwater Wetlands of the Mississippi River Delta: A Subsiding Coastline as a Proxy for Future Global Sea Level

NASA Astrophysics Data System (ADS)

White, J. R.; DeLaune, R. D.; Roy, E. D.; Corstanje, R.

2014-12-01

The highly visible phenomenon of wetland loss in coastal Louisiana (LA) is examined through the prism of carbon accumulation, wetland loss and greenhouse gas (GHG) emissions. The Mississippi River Deltaic region experiences higher relative sea level rise due to coupled subsidence and eustatic sea level rise allowing this region to serve as a proxy for future projected golbal sea level rise. Carbon storage or sequestration in rapidly subsiding LA coastal marsh soils is based on vertical marsh accretion and areal change data. While coastal marshes sequester significant amount of carbon through vertical accretion, large amounts of carbon, previously sequested in the soil profile is lost through annual deterioration of these coastal marshes as well as through GHG emissions. Efforts are underway in Louisiana to access the carbon credit market in order to provide significant funding for coastal restoration projects. However, there is very large uncertainty on GHG emission rates related to both marsh type and temporal (daily and seasonal) effects. Very little data currently exists which addresses this uncertainty which can significantly affect the carbon credit value of a particular wetland system. We provide an analysis of GHG emission rates for coastal freshwater, brackish and and salt marshes compared to the net soil carbon sequestration rate. Results demonstrate that there is very high uncertainty on GHG emissions which can substantially alter the carbon credit value of a particular wetland system.

CARBON SEQUESTRATION AND PLANT COMMUNITY DYNAMICS FOLLOWING REFORESTATION OF TROPICAL PASTURE.

Treesearch

WHENDEE L. SILVER; LARA M. KUEPPERS; ARIEL E. LUGO; REBECCA OSTERTAG; VIRGINIA MATZEK

2004-01-01

Conversion of abandoned cattle pastures to secondary forests and plantations in the tropics has been proposed as a means to increase rates of carbon (C) sequestration from the atmosphere and enhance local biodiversity. We used a long-term tropical reforestation project (55–61 yr) to estimate rates of above- and belowground C sequestration and to investigate the impact...

Estimating the potential of carbon sequestration by Korean forestry sector under climate change and management scenarios

NASA Astrophysics Data System (ADS)

Lee, J.; Kim, M.; Son, Y.; Lee, W. K.

2017-12-01

Korean forests have recovered by the national-scale reforestation program and can contribute to the national greenhouse gas (GHG) mitigation goal. The forest carbon (C) sequestration is expected to change by climate change and forest management regime. In this context, estimating the changes in GHG mitigation potential of Korean forestry sector by climate and management is a timely issue. Thus, we estimated the forest C sequestration of Korea under four scenarios (2010­-2050): constant temperature with no management (CT_No), representative concentration pathway (RCP) 8.5 with no management (RCP_No), constant temperature with thinning management (CT_Man), and RCP 8.5 with thinning management (RCP_Man). Dynamic stand growth model (KO-G-Dynamic; for biomass) and forest C model (FBDC model; for non-biomass) were used at approximately 64,000 simulation units (1km2). As model input data, the forest data (e.g., forest type and stand age) and climate data were spatially prepared from the national forest inventories and the RCP 8.5 climate data. The model simulation results showed that the mean annual C sequestrations during the period (Tg C yr-1) were 11.0, 9.9, 11.5, and 10.5, respectively, under the CT_No, RCP_No, CT_Man, and RCP_Man, respectively, at the national scale. The C sequestration decreased with the time passage due to the maturity of the forests. The climate change seemed disadvantageous to the C sequestration by the forest ecosystems (≒ -1.0 Tg C yr-1) due to the increase in organic matter decomposition. In particular, the decrease in C sequestration by the climate change was greater for the needle-leaved species, compared to the broad-leaved species. Meanwhile, the forest management enhanced forest C sequestration (≒ 0.5 Tg C yr-1). Accordingly, implementing appropriate forest management strategies for adaptation would contribute to maintaining the C sequestration by Korean forestry sector under climate change. Acknowledgement: This study was supported by Korean Ministry of Environment (2014001310008).

How Are the Mathematical Identities of Low Achieving South African Eleventh Graders Related to Their Ability to Solve Mathematical Tasks?

ERIC Educational Resources Information Center

Cranfield, Corvell

2013-01-01

The construct of mathematical identity has recently been widely used in mathematics education with the intention to understand how students relate to and engage (or disengage) with mathematics. Grootenboer and Zevenbergen (2008) define mathematical identity as the students' knowledge, abilities, skills, beliefs, dispositions, attitudes and…

Public Views on the Gendering of Mathematics and Related Careers: International Comparisons

ERIC Educational Resources Information Center

Forgasz, Helen; Leder, Gilah; Tan, Hazel

2014-01-01

Mathematics continues to be an enabling discipline for Science, Technology, Engineering, and Mathematics (STEM)-based university studies and related careers. Explanatory models for females' underrepresentation in higher level mathematics and STEM-based courses comprise learner-related and environmental variables--including societal beliefs. Using…

Agricultural land abandonment in Mediterranean environment provides ecosystem services via soil carbon sequestration.

PubMed

Novara, Agata; Gristina, Luciano; Sala, Giovanna; Galati, Antonino; Crescimanno, Maria; Cerdà, Artemi; Badalamenti, Emilio; La Mantia, Tommaso

2017-01-15

Abandonment of agricultural land leads to several consequences for ecosystem functions. Agricultural abandonment may be a significant and low cost strategy for carbon sequestration and mitigation of anthropogenic CO 2 emissions due to the vegetation recovery and increase in soil organic matter. The aim of this study was to: (i) estimate the influence of different Soil Regions (areas characterized by a typical climate and parent material association) and Bioclimates (zones with homogeneous climatic regions and thermotype indices) on soil organic carbon (SOC) dynamics after agricultural land abandonment; and (ii) to analyse the efficiency of the agri-environment policy (agri-environment measures) suggested by the European Commission in relation to potential SOC stock ability in the Sicilian Region (Italy). In order to quantify the effects of agricultural abandonment on SOC, a dataset with original data that was sampled in Sicily and existing data from the literature were analysed according to the IPCC (Intergovernmental Panel on Climate Change) methodology. Results showed that abandonment of cropland soils increased SOC stock by 9.03MgCha -1 on average, ranging from 5.4MgCha -1 to 26.7MgCha -1 in relation to the Soil Region and Bioclimate. The estimation of SOC change after agricultural use permitted calculation of the payments for ecosystem service (PES) of C sequestration after agricultural land abandonment in relation to environmental benefits, increasing in this way the efficiency of PES. Considering the 14,337ha of abandoned lands in Sicily, the CO 2 emission as a whole was reduced by 887,745Mg CO 2 . Therefore, it could be concluded that abandoned agricultural fields represents a valid opportunity to mitigate agriculture sector emissions in Sicily. Copyright © 2016 Elsevier B.V. All rights reserved.

Ferric iron-bearing sediments as a mineral trap for CO2 sequestration: Iron reduction using sulfur-bearing waste gas

USGS Publications Warehouse

Palandri, J.L.; Kharaka, Y.K.

2005-01-01

We present a novel method for geologic sequestration of anthropogenic CO2 in ferrous carbonate, using ferric iron present in widespread redbeds and other sediments. Iron can be reduced by SO2 that is commonly a component of flue gas produced by combustion of fossil fuel, or by adding SO2 or H2S derived from other industrial processes to the injected waste gas stream. Equilibrium and kinetically controlled geochemical simulations at 120 bar and 50 and 100 ??C with SO2 or H2S show that iron can be transformed almost entirely to siderite thereby trapping CO2, and simultaneously, that sulfur can be converted predominantly to dissolved sulfate. If there is an insufficient amount of sulfur-bearing gas relative to CO2 as for typical flue gas, then some of the iron is not reduced, and some of the CO2 is not sequestered. If there is an excess of sulfur-bearing gas, then complete iron reduction is ensured, and some of the iron precipitates as pyrite or other solid iron sulfide, depending on their relative precipitation kinetics. Gas mixtures with insufficient sulfur relative to CO2 can be used in sediments containing Ca, Mg, or other divalent metals capable of precipitating carbonate minerals. For quartz arenite with an initial porosity of 21% and containing 0.25 wt.% Fe2O3, approximately 0.7 g of CO2 is sequestered per kg of rock, and the porosity decrease is less than 0.03%. Sequestration of CO2 using ferric iron has the advantage of disposing of SO2 that may already be present in the combustion gas. ?? 2005 Published by Elsevier B.V.

Intralober pulmonary sequestration with arterial supply from two different origins: a case report.

PubMed

Erden, Ersin Sukru; Yetim, Tulin Durgun; Balci, Ali; Akcay, Adnan Burak; Hakverdi, Sibel; Demirkose, Mesut

2012-01-01

Pulmonary sequestration is a rare anomaly, which does not have a connection with the bronchial system and gets its blood supply, generally, from the aorta or its branches. Anatomically, two different forms were described: intralobar and extralobar. Although 74% of intralobar pulmonary sequestrations get their blood supply from the descending thoracic aorta, they may get their blood supply from different arteries. Furthermore, there is more than one arterial anomaly in 14.8% of cases. We report an intralobar pulmonary sequestration, in which arterial blood supply is from two different origins (Arcus aorta and celiac trunk). To the best of our knowledge, this is the first case in the literature.

The Influence of Symbols and Equations on Understanding Mathematical Equivalence

ERIC Educational Resources Information Center

Powell, Sarah R.

2015-01-01

Students with mathematics difficulty demonstrate lower mathematics performance than typical-performing peers. One contributing factor to lower mathematics performance may be misunderstanding of mathematics symbols. In several studies related to the equal sign (=), students who received explicit instruction on the relational definition (i.e.,…

Investigations in Mathematics Education, Vol. 10, No. 1.

ERIC Educational Resources Information Center

Osborne, Alan R., Ed.

Eighteen research reports related to mathematics education are abstracted and analyzed. Studies include elementary, secondary, and college mathematics education areas. A majority of the studies relate to instruction and learning. Research related to mathematics education which was reported in RESOURCES IN EDUCATION and CURRENT INDEX TO JOURNALS IN…

The relative contributions of forest growth and areal expansion to forest biomass carbon

Treesearch

P. Li; J. Zhu; H. Hu; Z. Guo; Y. Pan; R. Birdsey; J. Fang

2016-01-01

Forests play a leading role in regional and global terrestrial carbon (C) cycles. Changes in C sequestration within forests can be attributed to areal expansion (increase in forest area) and forest growth (increase in biomass density). Detailed assessment of the relative contributions of areal expansion and forest growth to C sinks is crucial to reveal the mechanisms...

Is a Clean Development Mechanism project economically justified? Case study of an International Carbon Sequestration Project in Iran.

PubMed

Katircioglu, Salih; Dalir, Sara; Olya, Hossein G

2016-01-01

The present study evaluates a carbon sequestration project for the three plant species in arid and semiarid regions of Iran. Results show that Haloxylon performed appropriately in the carbon sequestration process during the 6 years of the International Carbon Sequestration Project (ICSP). In addition to a high degree of carbon dioxide sequestration, Haloxylon shows high compatibility with severe environmental conditions and low maintenance costs. Financial and economic analysis demonstrated that the ICSP was justified from an economic perspective. The financial assessment showed that net present value (NPV) (US$1,098,022.70), internal rate of return (IRR) (21.53%), and payback period (6 years) were in an acceptable range. The results of the economic analysis suggested an NPV of US$4,407,805.15 and an IRR of 50.63%. Therefore, results of this study suggest that there are sufficient incentives for investors to participate in such kind of Clean Development Mechanism (CDM) projects.

Soil carbon sequestration is a climate stabilization wedge: comments on Sommer and Bossio (2014).

PubMed

Lassaletta, Luis; Aguilera, Eduardo

2015-04-15

Sommer and Bossio (2014) model the potential soil organic carbon (SOC) sequestration in agricultural soils (croplands and grasslands) during the next 87 years, concluding that this process cannot be considered as a climate stabilization wedge. We argue, however, that the amounts of SOC potentially sequestered in both scenarios (pessimistic and optimistic) fulfil the requirements for being considered as wedge because in both cases at least 25 GtC would be sequestered during the next 50 years. We consider that it is precisely in the near future, and meanwhile other solutions are developed, when this stabilization effort is most urgent even if after some decades the sequestration rate is significantly reduced. Indirect effects of SOC sequestration on mitigation could reinforce the potential of this solution. We conclude that the sequestration of organic carbon in agricultural soils as a climate change mitigation tool still deserves important attention for scientists, managers and policy makers. Copyright © 2015 Elsevier Ltd. All rights reserved.

Barriers and Prospects of Carbon Sequestration in India.

PubMed

Gupta, Anjali; Nema, Arvind K

2014-04-01

Carbon sequestration is considered a leading technology for reducing carbon dioxide (CO2) emissions from fossil-fuel based electricity generating power plants and could permit the continued use of coal and gas whilst meeting greenhouse gas targets. India will become the world's third largest emitter of CO2 by 2015. Considering the dependence of health of the Indian global economy, there is an imperative need to develop a global approach which could address the capturing and securely storing carbon dioxide emitted from an array of energy. Therefore technology such as carbon sequestration will deliver significant CO2 reductions in a timely fashion. Considerable energy is required for the capture, compression, transport and storage steps. With the availability of potential technical storage methods for carbon sequestration like forest, mineral and geological storage options with India, it would facilitate achieving stabilization goal in the near future. This paper examines the potential carbon sequestration options available in India and evaluates them with respect to their strengths, weakness, threats and future prospects.

Relation between Approximate Number System Acuity and Mathematical Achievement: The Influence of Fluency

PubMed Central

Wang, Li; Sun, Yuhua; Zhou, Xinlin

2016-01-01

Previous studies have observed inconsistent relations between the acuity of the Approximate Number System (ANS) and mathematical achievement. In this paper, we hypothesize that the relation between ANS acuity and mathematical achievement is influenced by fluency; that is, the mathematical achievement test covering a greater expanse of mathematical fluency may better reflect the relation between ANS acuity and mathematics skills. We explored three types of mathematical achievement tests utilized in this study: Subtraction, graded, and semester-final examination. The subtraction test was designed to measure the mathematical fluency. The graded test was more fluency-based than the semester-final examination, but both involved the same mathematical knowledge from the class curriculum. A total of 219 fifth graders from primary schools were asked to perform all three tests, then given a numerosity comparison task, a visual form perception task (figure matching), and a series of other tasks to assess general cognitive processes (mental rotation, non-verbal matrix reasoning, and choice reaction time). The findings were consistent with our expectations. The relation between ANS acuity and mathematical achievement was particularly clearly reflected in the participants’ performance on the visual form perception task, which supports the domain-general explanations for the underlying mechanisms of the relation between ANS acuity and math achievement. PMID:28066291

Integrated management of carbon sequestration and biomass utilization opportunities in a changing climate: Proceedings of the 2009 National Silviculture Workshop; 2009 June 15-18; Boise, ID.

Treesearch

Theresa B. Jain; Russell T. Graham; Jonathan Sandquist

2010-01-01

Forests are important for carbon sequestration and how they are manipulated either through natural or human induced disturbances can have an effect on CO2 emissions and carbon sequestration. The 2009 National Silviculture Workshop presented scientific information and management strategies to meet a variety of objectives while simultaneously addressing carbon...

Reply to 'Comments on upscaling geochemical reaction rates usingpore-scale network modeling' by Peter C. Lichtner and Qinjun Kang

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Li; Peters, Catherine A.; Celia, Michael A.

2006-05-03

Our paper "Upscaling geochemical reaction rates usingpore-scale network modeling" presents a novel application of pore-scalenetwork modeling to upscale mineral dissolution and precipitationreaction rates from the pore scale to the continuum scale, anddemonstrates the methodology by analyzing the scaling behavior ofanorthite and kaolinite reaction kinetics under conditions related to CO2sequestration. We conclude that under highly acidic conditions relevantto CO2 sequestration, the traditional continuum-based methodology may notcapture the spatial variation in concentrations from pore to pore, andscaling tools may be important in correctly modeling reactive transportprocesses in such systems. This work addresses the important butdifficult question of scaling mineral dissolution and precipitationreactionmore » kinetics, which is often ignored in fields such as geochemistry,water resources, and contaminant hydrology. Although scaling of physicalprocesses has been studied for almost three decades, very few studieshave examined the scaling issues related to chemical processes, despitetheir importance in governing the transport and fate of contaminants insubsurface systems.« less

Big Sky Carbon Sequestration Partnership

DOE Office of Scientific and Technical Information (OSTI.GOV)

Susan Capalbo

2005-12-31

The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I are organized into four areas: (1) Evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; (2) Development of GIS-based reporting framework that links with national networks; (3) Design of an integrated suite of monitoring, measuring, and verification technologies, market-based opportunities for carbon management, and an economic/risk assessmentmore » framework; (referred to below as the Advanced Concepts component of the Phase I efforts) and (4) Initiation of a comprehensive education and outreach program. As a result of the Phase I activities, the groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that complements the ongoing DOE research agenda in Carbon Sequestration. The geology of the Big Sky Carbon Sequestration Partnership Region is favorable for the potential sequestration of enormous volume of CO{sub 2}. The United States Geological Survey (USGS 1995) identified 10 geologic provinces and 111 plays in the region. These provinces and plays include both sedimentary rock types characteristic of oil, gas, and coal productions as well as large areas of mafic volcanic rocks. Of the 10 provinces and 111 plays, 1 province and 4 plays are located within Idaho. The remaining 9 provinces and 107 plays are dominated by sedimentary rocks and located in the states of Montana and Wyoming. The potential sequestration capacity of the 9 sedimentary provinces within the region ranges from 25,000 to almost 900,000 million metric tons of CO{sub 2}. Overall every sedimentary formation investigated has significant potential to sequester large amounts of CO{sub 2}. Simulations conducted to evaluate mineral trapping potential of mafic volcanic rock formations located in the Idaho province suggest that supercritical CO{sub 2} is converted to solid carbonate mineral within a few hundred years and permanently entombs the carbon. Although MMV for this rock type may be challenging, a carefully chosen combination of geophysical and geochemical techniques should allow assessment of the fate of CO{sub 2} in deep basalt hosted aquifers. Terrestrial carbon sequestration relies on land management practices and technologies to remove atmospheric CO{sub 2} where it is stored in trees, plants, and soil. This indirect sequestration can be implemented today and is on the front line of voluntary, market-based approaches to reduce CO{sub 2} emissions. Initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil Carbon (C) on rangelands, and forested, agricultural, and reclaimed lands. Rangelands can store up to an additional 0.05 mt C/ha/yr, while the croplands are on average four times that amount. Estimates of technical potential for soil sequestration within the region in cropland are in the range of 2.0 M mt C/yr over 20 year time horizon. This is equivalent to approximately 7.0 M mt CO{sub 2}e/yr. The forestry sinks are well documented, and the potential in the Big Sky region ranges from 9-15 M mt CO{sub 2} equivalent per year. Value-added benefits include enhanced yields, reduced erosion, and increased wildlife habitat. Thus the terrestrial sinks provide a viable, environmentally beneficial, and relatively low cost sink that is available to sequester C in the current time frame. The Partnership recognizes the critical importance of measurement, monitoring, and verification technologies to support not only carbon trading but all policies and programs that DOE and other agencies may want to pursue in support of GHG mitigation. The efforts in developing and implementing MMV technologies for geological and terrestrial sequestration reflect this concern. Research in Phase I has identified and validated best management practices for soil C in the Partnership region, and outlined a risk/cost effectiveness framework to make comparative assessments of each viable sink, taking into account economic costs, offsetting benefits, scale of sequestration opportunities, spatial and time dimensions, environmental risks, and long-term viability. This is the basis for the integrative analysis that will be undertaken in Phase II to work with industry, state and local governments and with the pilot demonstration projects to quantify the economic costs and risks associated with all opportunities for carbon storage in the Big Sky region. Scientifically sound MMV is critical for public acceptance of these technologies.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Yiqi; Shi, Zheng; Lu, Xingjie

Terrestrial ecosystems have absorbed roughly 30 % of anthropogenic CO 2 emissions over the past decades, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling and experimental and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under global change is still not very clear. Here we develop a new framework for understanding transient dynamics of terrestrial C storage through mathematical analysis and numerical experiments. Our analysis indicates that the ultimate force driving ecosystem C storage change is the C storage capacity, which is jointly determined by ecosystem C inputmore » (e.g., net primary production, NPP) and residence time. Since both C input and residence time vary with time, the C storage capacity is time-dependent and acts as a moving attractor that actual C storage chases. The rate of change in C storage is proportional to the C storage potential, which is the difference between the current storage and the storage capacity. The C storage capacity represents instantaneous responses of the land C cycle to external forcing, whereas the C storage potential represents the internal capability of the land C cycle to influence the C change trajectory in the next time step. The influence happens through redistribution of net C pool changes in a network of pools with different residence times. Moreover, this and our other studies have demonstrated that one matrix equation can replicate simulations of most land C cycle models (i.e., physical emulators). As a result, simulation outputs of those models can be placed into a three-dimensional (3-D) parameter space to measure their differences. The latter can be decomposed into traceable components to track the origins of model uncertainty. In addition, the physical emulators make data assimilation computationally feasible so that both C flux- and pool-related datasets can be used to better constrain model predictions of land C sequestration. Overall, this new mathematical framework offers new approaches to understanding, evaluating, diagnosing, and improving land C cycle models.« less

Visual short term memory related brain activity predicts mathematical abilities.

PubMed

Boulet-Craig, Aubrée; Robaey, Philippe; Lacourse, Karine; Jerbi, Karim; Oswald, Victor; Krajinovic, Maja; Laverdière, Caroline; Sinnett, Daniel; Jolicoeur, Pierre; Lippé, Sarah

2017-07-01

Previous research suggests visual short-term memory (VSTM) capacity and mathematical abilities are significantly related. Moreover, both processes activate similar brain regions within the parietal cortex, in particular, the intraparietal sulcus; however, it is still unclear whether the neuronal underpinnings of VSTM directly correlate with mathematical operation and reasoning abilities. The main objective was to investigate the association between parieto-occipital brain activity during the retention period of a VSTM task and performance in mathematics. The authors measured mathematical abilities and VSTM capacity as well as brain activity during memory maintenance using magnetoencephalography (MEG) in 19 healthy adult participants. Event-related magnetic fields (ERFs) were computed on the MEG data. Linear regressions were used to estimate the strength of the relation between VSTM related brain activity and mathematical abilities. The amplitude of parieto-occipital cerebral activity during the retention of visual information was related to performance in 2 standardized mathematical tasks: mathematical reasoning and calculation fluency. The findings show that brain activity during retention period of a VSTM task is associated with mathematical abilities. Contributions of VSTM processes to numerical cognition should be considered in cognitive interventions. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Soil Organic Carbon Sequestration by Tillage and Crop Rotation: A Global Data Analysis

DOE Data Explorer

West, Tristram O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Post, Wilfred M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2002-01-01

Changes in agricultural management can potentially increase the accumulation rate of soil organic carbon (SOC), thereby sequestering CO2 from the atmosphere. This study was conducted to quantify potential soil carbon (C) sequestration rates for different crops in response to decreasing tillage intensity or enhancing rotation complexity, and to estimate the duration of time over which sequestration may occur. Analyses of C sequestration rates were completed using a global database of 67 long-term agricultural experiments, consisting of 276 paired treatments. Results indicate, on average, that a change from conventional tillage (CT) to no-till (NT) can sequester 57 ± 14 g C m^–2 yr^–1, excluding wheat (Triticum aestivum L.)-fallow systems which may not result in SOC accumulation with a change from CT to NT. Enhancing rotation complexity can sequester an average 14 ± 11 g C m^–2 yr^–1, excluding a change from continuous corn (Zea mays L.) to corn-soybean (Glycine max L.) which may not result in a significant accumulation of SOC. Carbon sequestration rates, with a change from CT to NT, can be expected to peak in 5-10 yr with SOC reaching a new equilibrium in 15-20 yr. Following initiation of an enhancement in rotation complexity, SOC may reach a new equilibrium in approximately 40-60 yr. Carbon sequestration rates, estimated for a number of individual crops and crop rotations in this study, can be used in spatial modeling analyses to more accurately predict regional, national, and global C sequestration potentials.

Carbon Sequestration Estimation of Street Trees Based on Point Cloud from Vehicle-Borne Laser Scanning System

NASA Astrophysics Data System (ADS)

Zhao, Y.; Hu, Q.

2017-09-01

Continuous development of urban road traffic system requests higher standards of road ecological environment. Ecological benefits of street trees are getting more attention. Carbon sequestration of street trees refers to the carbon stocks of street trees, which can be a measurement for ecological benefits of street trees. Estimating carbon sequestration in a traditional way is costly and inefficient. In order to solve above problems, a carbon sequestration estimation approach for street trees based on 3D point cloud from vehicle-borne laser scanning system is proposed in this paper. The method can measure the geometric parameters of a street tree, including tree height, crown width, diameter at breast height (DBH), by processing and analyzing point cloud data of an individual tree. Four Chinese scholartree trees and four camphor trees are selected for experiment. The root mean square error (RMSE) of tree height is 0.11m for Chinese scholartree and 0.02m for camphor. Crown widths in X direction and Y direction, as well as the average crown width are calculated. And the RMSE of average crown width is 0.22m for Chinese scholartree and 0.10m for camphor. The last calculated parameter is DBH, the RMSE of DBH is 0.5cm for both Chinese scholartree and camphor. Combining the measured geometric parameters and an appropriate carbon sequestration calculation model, the individual tree's carbon sequestration will be estimated. The proposed method can help enlarge application range of vehicle-borne laser point cloud data, improve the efficiency of estimating carbon sequestration, construct urban ecological environment and manage landscape.

State and Regional Control of Geological Carbon Sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reitze, Arnold; Durrant, Marie

2011-03-01

The United States has economically recoverable coal reserves of about 261 billion tons, which is in excess of a 250-­year supply based on 2009 consumption rates. However, in the near future the use of coal may be legally restricted because of concerns over the effects of its combustion on atmospheric carbon dioxide concentrations. Carbon capture and geologic sequestration offer one method to reduce carbon emissions from coal and other hydrocarbon energy production. While the federal government is providing increased funding for carbon capture and sequestration, recent congressional legislative efforts to create a framework for regulating carbon emissions have failed. However,more » regional and state bodies have taken significant actions both to regulate carbon and facilitate its capture and sequestration. This article explores how regional bodies and state government are addressing the technical and legal problems that must be resolved in order to have a viable carbon sequestration program. Several regional bodies have formed regulations and model laws that affect carbon capture and storage, and three bodies comprising twenty-three states—the Regional Greenhouse Gas Initiative, the Midwest Regional Greenhouse Gas Reduction Accord, and the Western Climate initiative—have cap-­and-trade programs in various stages of development. State property, land use and environmental laws affect the development and implementation of carbon capture and sequestration projects, and unless federal standards are imposed, state laws on torts and renewable portfolio requirements will directly affect the liability and viability of these projects. This paper examines current state laws and legislative efforts addressing carbon capture and sequestration.« less

Rapid assessment of U.S. forest and soil organic carbon storage and forest biomass carbon-sequestration capacity

USGS Publications Warehouse

Sundquist, Eric T.; Ackerman, Katherine V.; Bliss, Norman B.; Kellndorfer, Josef M.; Reeves, Matt C.; Rollins, Matthew G.

2009-01-01

This report provides results of a rapid assessment of biological carbon stocks and forest biomass carbon sequestration capacity in the conterminous United States. Maps available from the U.S. Department of Agriculture are used to calculate estimates of current organic carbon storage in soils (73 petagrams of carbon, or PgC) and forest biomass (17 PgC). Of these totals, 3.5 PgC of soil organic carbon and 0.8 PgC of forest biomass carbon occur on lands managed by the U.S. Department of the Interior (DOI). Maps of potential vegetation are used to estimate hypothetical forest biomass carbon sequestration capacities that are 3–7 PgC higher than current forest biomass carbon storage in the conterminous United States. Most of the estimated hypothetical additional forest biomass carbon sequestration capacity is accrued in areas currently occupied by agriculture and development. Hypothetical forest biomass carbon sequestration capacities calculated for existing forests and woodlands are within ±1 PgC of estimated current forest biomass carbon storage. Hypothetical forest biomass sequestration capacities on lands managed by the DOI in the conterminous United States are 0–0.4 PgC higher than existing forest biomass carbon storage. Implications for forest and other land management practices are not considered in this report. Uncertainties in the values reported here are large and difficult to quantify, particularly for hypothetical carbon sequestration capacities. Nevertheless, this rapid assessment helps to frame policy and management discussion by providing estimates that can be compared to amounts necessary to reduce predicted future atmospheric carbon dioxide levels.

Carbon sequestration index as a determinant for climate change mitigation: Case study of Bintan Island

NASA Astrophysics Data System (ADS)

Wahyudi, A.'an J.; Afdal; Prayudha, Bayu; Dharmawan, I. W. E.; Irawan, Andri; Abimanyu, Haznan; Meirinawati, Hanny; Surinati, Dewi; Syukri, Agus F.; Yuliana, Chitra I.; Yuniati, Putri I.

2018-02-01

The increase of the anthropogenic carbon dioxide (CO2) affects the global carbon cycle altering the atmospheric system and initiates the climate changes. There are two ways to mitigate these changes, by maintaining the greenhouse gasses below the carbon budget and by conserving the marine and terrestrial vegetation for carbon sequestration. These two strategies become variable to the carbon sequestration index (CSI) that represents the potential of a region in carbon sequestration, according to its natural capacity. As a study case, we conducted carbon sequestration research in Bintan region (Bintan Island and its surrounding), Riau Archipelago province. This research was aimed to assess the CSI and its possibility for climate change mitigation. We observed carbon sequestration of seagrass meadows and mangrove, greenhouse gas (CO2) emission (correlated to population growth, the increase of vehicles), and CSI. Bintan region has 125,849.9 ha of vegetation area and 14,879.6 ha of terrestrial and marine vegetation area, respectively. Both vegetation areas are able to sequester 0.262 Tg C yr-1 in total and marine vegetation contributes about 77.1%. Total CO2 emission in Bintan region is up to 0.273 Tg C yr-1, produced by transportation, industry and land use sectors. Therefore, CSI of the Bintan region is 0.98, which is above the global average (i.e. 0.58). This value demonstrates that the degree of sequestration is comparable to the total carbon emission. This result suggests that Bintan’s vegetation has high potential for reducing greenhouse gas effects.

The nonlinear relations of the approximate number system and mathematical language to early mathematics development.

PubMed

Purpura, David J; Logan, Jessica A R

2015-12-01

Both mathematical language and the approximate number system (ANS) have been identified as strong predictors of early mathematics performance. Yet, these relations may be different depending on a child's developmental level. The purpose of this study was to evaluate the relations between these domains across different levels of ability. Participants included 114 children who were assessed in the fall and spring of preschool on a battery of academic and cognitive tasks. Children were 3.12 to 5.26 years old (M = 4.18, SD = .58) and 53.6% were girls. Both mixed-effect and quantile regressions were conducted. The mixed-effect regressions indicated that mathematical language, but not the ANS, nor other cognitive domains, predicted mathematics performance. However, the quantile regression analyses revealed a more nuanced relation among domains. Specifically, it was found that mathematical language and the ANS predicted mathematical performance at different points on the ability continuum. These dual nonlinear relations indicate that different mechanisms may enhance mathematical acquisition dependent on children's developmental abilities. (c) 2015 APA, all rights reserved).

Terrestrial C sequestration at elevated CO2 and temperature: the role of dissolved organic N loss

USGS Publications Warehouse

Rastetter, Edward B.; Perakis, Steven S.; Shaver, Gaius R.; Agren, Goran I.

2005-01-01

We used a simple model of carbon–nitrogen (C–N) interactions in terrestrial ecosystems to examine the responses to elevated CO2 and to elevated CO2 plus warming in ecosystems that had the same total nitrogen loss but that differed in the ratio of dissolved organic nitrogen (DON) to dissolved inorganic nitrogen (DIN) loss. We postulate that DIN losses can be curtailed by higher N demand in response to elevated CO2, but that DON losses cannot. We also examined simulations in which DON losses were held constant, were proportional to the amount of soil organic matter, were proportional to the soil C:N ratio, or were proportional to the rate of decomposition. We found that the mode of N loss made little difference to the short‐term (<60 years) rate of carbon sequestration by the ecosystem, but high DON losses resulted in much lower carbon sequestration in the long term than did low DON losses. In the short term, C sequestration was fueled by an internal redistribution of N from soils to vegetation and by increases in the C:N ratio of soils and vegetation. This sequestration was about three times larger with elevated CO2 and warming than with elevated CO2 alone. After year 60, C sequestration was fueled by a net accumulation of N in the ecosystem, and the rate of sequestration was about the same with elevated CO2 and warming as with elevated CO2alone. With high DON losses, the ecosystem either sequestered C slowly after year 60 (when DON losses were constant or proportional to soil organic matter) or lost C (when DON losses were proportional to the soil C:N ratio or to decomposition). We conclude that changes in long‐term C sequestration depend not only on the magnitude of N losses, but also on the form of those losses.

A novel dendrochronological approach reveals drivers of carbon sequestration in tree species of riparian forests across spatiotemporal scales.

PubMed

Rieger, Isaak; Kowarik, Ingo; Cherubini, Paolo; Cierjacks, Arne

2017-01-01

Aboveground carbon (C) sequestration in trees is important in global C dynamics, but reliable techniques for its modeling in highly productive and heterogeneous ecosystems are limited. We applied an extended dendrochronological approach to disentangle the functioning of drivers from the atmosphere (temperature, precipitation), the lithosphere (sedimentation rate), the hydrosphere (groundwater table, river water level fluctuation), the biosphere (tree characteristics), and the anthroposphere (dike construction). Carbon sequestration in aboveground biomass of riparian Quercus robur L. and Fraxinus excelsior L. was modeled (1) over time using boosted regression tree analysis (BRT) on cross-datable trees characterized by equal annual growth ring patterns and (2) across space using a subsequent classification and regression tree analysis (CART) on cross-datable and not cross-datable trees. While C sequestration of cross-datable Q. robur responded to precipitation and temperature, cross-datable F. excelsior also responded to a low Danube river water level. However, CART revealed that C sequestration over time is governed by tree height and parameters that vary over space (magnitude of fluctuation in the groundwater table, vertical distance to mean river water level, and longitudinal distance to upstream end of the study area). Thus, a uniform response to climatic drivers of aboveground C sequestration in Q. robur was only detectable in trees of an intermediate height class and in taller trees (>21.8m) on sites where the groundwater table fluctuated little (≤0.9m). The detection of climatic drivers and the river water level in F. excelsior depended on sites at lower altitudes above the mean river water level (≤2.7m) and along a less dynamic downstream section of the study area. Our approach indicates unexploited opportunities of understanding the interplay of different environmental drivers in aboveground C sequestration. Results may support species-specific and locally adapted forest management plans to increase carbon dioxide sequestration from the atmosphere in trees. Copyright © 2016 Elsevier B.V. All rights reserved.

Deep horizons: Soil Carbon sequestration and storage potential in grassland soils

NASA Astrophysics Data System (ADS)

Torres-Sallan, Gemma; Schulte, Rogier; Lanigan, Gary J.; Byrne, Kenneth A.; Reidy, Brian; Creamer, Rachel

2016-04-01

Soil Organic Carbon (SOC) enhances soil fertility, holding nutrients in a plant-available form. It also improves aeration and water infiltration. Soils are considered a vital pool for C (Carbon) sequestration, as they are the largest pool of C after the oceans, and contain 3.5 more C than the atmosphere. SOC models and inventories tend to focus on the top 30 cm of soils, only analysing total SOC values. Association of C with microaggregates (53-250 μm) and silt and clay (<53 μm) is considered C sequestration as these fractions offer the greatest protection against mineralization. This study assessed the role of aggregation in C sequestration throughout the profile, down to 1 m depth, of 30 grassland sites divided in 6 soil types. One kg sample was collected for each horizon, sieved at 8 mm and dried at 40 °C. Through a wet sieving procedure, four aggregate sizes were isolated: large macroaggregates (>2000 μm); macroaggregates (250-2000 μm); microaggregates and silt & clay. Organic C associated to each aggregate fraction was analysed on a LECO combustion analyser. Sand-free C was calculated for each aggregate size. For all soil types, 84% of the SOC located in the first 30 cm was contained inside macroaggregates and large macroaggregates. Given that this fraction has a turnover time of 1 to 10 years, sampling at that depth only provides information on the labile fraction in soil, and does not consider the longer term C sequestration potential. Only when looking at the whole profile, two clear trends could be observed: 1) soils with a clay increase at depth had most of their C located in the silt and clay fractions, which indicate their enhanced C sequestration capacity, 2) free-draining soils had a bigger part of their SOC located in the macroaggregate fractions. These results indicate that current C inventories and models that focus on the top 30 cm, do not accurately measure soil C sequestration potential in soils, but rather the more labile fraction. However, at depth soil forming processes have been identified as a major factor influencing C sequestration potential in soils. This has a major impact in further quantifying and sustaining C sequestration into the future. Soils with a high sequestration potential at depth need to be managed to enhance the residence time to contribute to future off-setting of greenhouse gas emissions.

Perspectives for genetic engineering for the phytoremediation of arsenic-contaminated environments: from imagination to reality?

PubMed

Zhu, Yong-Guan; Rosen, Barry P

2009-04-01

Phytoremediation to clean up arsenic-contaminated environments has been widely hailed as environmentally friendly and cost effective, and genetic engineering is believed to improve the efficiency and versatility of phytoremediation. Successful genetic engineering requires the thorough understanding of the mechanisms involved in arsenic tolerance and accumulation by natural plant species. Key mechanisms include arsenate reduction, arsenic sequestration in vacuoles of root or shoot, arsenic loading to the xylem, and volatilization through the leaves. Key advances include the identification of arsenic (As) translocation from root to shoot in the As hyperaccumulator, Pteris vittata, and the characterization of related key genes from hyperaccumulator and nonaccumulators. In this paper we have proposed three pathways for genetic engineering: arsenic sequestration in the root, hyperaccumulation of arsenic in aboveground tissues, and phytovolatilization.

Evaluation of the in vivo disintegration of solid dosage forms of a bile acid sequestrant in dogs using gamma-scintigraphy and correlation to in vitro disintegration.

PubMed

Hussain, Munir A; Chang, Rong-Kun; Sandefer, Erik; Page, Richard C; Digenis, George A

2003-03-01

[corrected] To evaluate the in vivo disintegration behavior of tablets and capsules of a bile acid sequestrant, DMP 504, in beagle dogs and to assess the significance of the in vitro disintegration of the dosage forms on subsequent in vivo behavior in order to draw possible in vitro-in vivo correlations. Tablet and capsule formulations of a bile acid sequestrant, DMP 504, were formulated with samarium oxide and neutron activated to produce radioactive 53Sm to noninvasively evaluate their in vivo behavior in beagle dogs by gamma-scintigraphy. A four-way crossover design was completed (n = 4) in which (a) tablets from two different batches were administered under the fasted condition and manufactured using different lots of drug substance where one batch exhibited relatively faster in vitro disintegration time (30 min) than the other tablet batch, which resulted in slower disintegration (45 min), (b) a capsule formulation was administered to fasted beagles, and (c) the tablet having slower in vitro disintegration was also administered in the fed state, and its in vivo disintegration was compared to that observed in the fasted state. Tablets manufactured using a lot of DMP 504 having relatively fast in vitro disintegration (approximately 30 min) resulted in relatively rapid in vivo disintegration time (15 min) in the fasted condition. This in vivo disintegration time was comparable to the in vivo disintegration of the capsules (17 min) even though the in vitro capsule disintegration time was considerably faster (2 min). Tablets prepared using a drug substance that provided a longer in vitro disintegration time (approximately 45 min) resulted in a slower in vivo disintegration (63 min). There was no difference observed in the in vivo disintegration behavior in fasted and fed dogs for the tablets that provided slower in vitro disintegration. In vivo disintegration of tablets of the bile acid sequestrant DMP 504 correlated with in vitro disintegration times. Gamma-Scintigraphy continues to be a good tool to use during early stages of product development to investigate in vivo performance of dosage forms. The results of this study provided evidence that the physical chemical specifications of the drug substance may not always be indicative of in vitro or in vivo performance of tablet dosage form, even when formulation and process are not changed.

Mathematics Self-Efficacy, Ethnic Identity, Gender, and Career Interests Related to Mathematics and Science.

ERIC Educational Resources Information Center

O'Brien, Virginia; Martinez-Pons, Manual; Kopala, Mary

1999-01-01

Surveyed 11th graders to examine the relations among mathematics self-efficacy (SE), gender, ethnic identity, and career interests (CI) in mathematics and science. Researchers also examined socioeconomic status (SES) and academic achievement. Science CI was predicted solely by science-mathematics SE. SE was predicted by academic performance and…

Attitudes toward and approaches to learning first-year university mathematics.

PubMed

Alkhateeb, Haitham M; Hammoudi, Lakhdar

2006-08-01

This study examined the relationship for 180 undergraduate students enrolled in a first-year university calculus course between attitudes toward mathematics and approaches to learning mathematics using the Mathematics Attitude Scale and the Approaches to Learning Mathematics Questionnaire, respectively. Regression analyses indicated that scores for the Mathematics Attitude Scale were negatively related to scores for the Surface Approach and accounted for 10.4% of the variance and scores for the Mathematics Attitude Scale were positively related to scores for the Deep Approach to learning mathematics and accounted for 31.7% of the variance.

Micromotor-Based Biomimetic Carbon Dioxide Sequestration: Towards Mobile Microscrubbers.

PubMed

Uygun, Murat; Singh, Virendra V; Kaufmann, Kevin; Uygun, Deniz A; de Oliveira, Severina D S; Wang, Joseph

2015-10-26

We describe a mobile CO2 scrubbing platform that offers a greatly accelerated biomimetic sequestration based on a self-propelled carbonic anhydrase (CA) functionalized micromotor. The CO2 hydration capability of CA is coupled with the rapid movement of catalytic micromotors, and along with the corresponding fluid dynamics, results in a highly efficient mobile CO2 scrubbing microsystem. The continuous movement of CA and enhanced mass transport of the CO2 substrate lead to significant improvements in the sequestration efficiency and speed over stationary immobilized or free CA platforms. This system is a promising approach to rapid and enhanced CO2 sequestration platforms for addressing growing concerns over the buildup of greenhouse gas. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of Protective Coatings for Co-Sequestration Processes and Pipelines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bierwagen, Gordon; Huang, Yaping

2011-11-30

The program, entitled Development of Protective Coatings for Co-Sequestration Processes and Pipelines, examined the sensitivity of existing coating systems to supercritical carbon dioxide (SCCO2) exposure and developed new coating system to protect pipelines from their corrosion under SCCO2 exposure. A literature review was also conducted regarding pipeline corrosion sensors to monitor pipes used in handling co-sequestration fluids. Research was to ensure safety and reliability for a pipeline involving transport of SCCO2 from the power plant to the sequestration site to mitigate the greenhouse gas effect. Results showed that one commercial coating and one designed formulation can both be supplied asmore » potential candidates for internal pipeline coating to transport SCCO2.« less

Section 4: Evaluation of carbon management requirements

NASA Astrophysics Data System (ADS)

The chapters in this section are perhaps the broadest of the book. They discuss the integrated set of factors that affect carbon management in general. Roed-Larsen and Flach start the section with a detailed summary of current accreditation schemes. Verification of carbon credits is critical for validation of monetary sequestration incentives. Commercial-scale geologic sequestration will likely not advance unless such financial incentives are implemented. The type of incentive also is critical. For example, in the one country where a carbon tax is in place, Norway, commercial geologic sequestration has been underway since 1996. In other countries, where a cap-and-trade system is in place, and of course in countries where no incentives are offered, no commercial carbon sequestration is taking place.

Mathematical Representation by Students in Building Relational Understanding on Concepts of Area and Perimeter of Rectangle

ERIC Educational Resources Information Center

Anwar, Rahmad Bustanul; Yuwono, Ipung; As'ari, Abdur Rahman; Sisworo; Dwi, Rahmawati

2016-01-01

Representation is an important aspect of learners in building a relational understanding of mathematical concepts. But the ability of a mathematical representation of students in building relational understanding is still very limited. The purpose of this research is to description of mathematical representation of students who appear in building…

Hybrid Task Design: Connecting Learning Opportunities Related to Critical Thinking and Statistical Thinking

ERIC Educational Resources Information Center

Kuntze, Sebastian; Aizikovitsh-Udi, Einav; Clarke, David

2017-01-01

Stimulating thinking related to mathematical content is the focus of many tasks in the mathematics classroom. Beyond such content-related thinking, promoting forms of higher order thinking is among the goals of mathematics instruction as well. So-called hybrid tasks focus on combining both goals: they aim at fostering mathematical thinking and…

Biogeologic Carbon Sequestration - a Cost-Effective Proposal

NASA Astrophysics Data System (ADS)

Shaw, G. H.; Kuhns, R.

2009-05-01

Carbon sequestration has been proposed as a strategy for reducing the impact of carbon dioxide emissions from burning of fossil fuels. There are two main routes: 1) capture CO2 emissions from power plants or other large point sources followed by some form of "burial/sequestration", and 2) extraction of CO2 from the ambient atmosphere (involving substantial concentration relative to atmospheric levels) also followed by burial/sequestration. In either case the goal is to achieve significant long-term isolation of CO2 at an economically sustainable price, perhaps measured by some "market price" for CO2, such as the European carbon futures market, where the price is now (2/3/09) about 14-15/tonne of CO2. The second approach, removal of CO2 from the atmosphere, has the potential benefit of reversing the previous buildup of atmospheric CO2, and perhaps even providing a means to "adjust" terrestrial climate by regulating atmospheric CO2 concentrations. For the present, ideas of planetary "geo-engineering" are not as popular as reducing the impact of continued CO2 emissions. In fact, the energy and capital costs of extraction from a dilute atmosphere appear to make this approach uneconomical. Proposals to fertilize the open ocean suffer from concerns about long term ecosystem effects, to say nothing of a lack of verifiability. There is, however, an approach using biological systems that can not only extract significant amounts of CO2, but can do so cost-effectively. Lakes are known in which primary productivity approaches or exceeds 1gm C/cm2-yr. This equates to removal of 35,000 tonnes of CO2 per km2 per year, with a "market value" of about 500,000/yr. Such productivity only occurs under highly eutrophic conditions, and presumably requires significant nutrient additions. As such it would be unthinkable to pursue this technique on a large scale in extant lakes. If, however, it is possible to produce one or more large artificial lakes under acceptable conditions it is conceivable that this approach to carbon sequestration could prove invaluable in both the near and long term.

Effective CO2 sequestration monitoring using joint inversion result of seismic and electromagnetic data

NASA Astrophysics Data System (ADS)

Noh, K.; Jeong, S.; Seol, S. J.; Byun, J.; Kwon, T.

2015-12-01

Man-made carbon dioxide (CO2) released into the atmosphere is a significant contributor to the greenhouse gas effect and related global warming. Sequestration of CO2 into saline aquifers has been proposed as one of the most practical options of all geological sequestration possibilities. During CO2 geological sequestration, monitoring is indispensable to delineate the change of CO2 saturation and migration of CO2 in the subsurface. Especially, monitoring of CO2 saturation in aquifers provides useful information for determining amount of injected CO2. Seismic inversion can provide the migration of CO2 plume with high resolution because velocity is reduced when CO2 replaces the pore fluid during CO2 injection. However, the estimation of CO2 saturation using the seismic method is difficult due to the lower sensitivity of the velocity to the saturation when the CO2 saturation up to 20%. On the other hand, marine controlled-source EM (mCSEM) inversion is sensitive to the resistivity changes resulting from variations in CO2 saturation, even though it has poor resolution than seismic method. In this study, we proposed an effective CO2 sequestration monitoring method using joint inversion of seismic and mCSEM data based on a cross-gradient constraint. The method was tested with realistic CO2 injection models in a deep brine aquifer beneath a shallow sea which is selected with consideration for the access convenience for the installation of source and receiver and an environmental safety. Resistivity images of CO2 plume by the proposed method for different CO2 injection stages have been significantly improved over those obtained from individual EM inversion. In addition, we could estimate a reliable CO2 saturation by rock physics model (RPM) using the P-wave velocity and the improved resistivity. The proposed method is a basis of three-dimensional estimation of reservoir parameters such as porosity and fluid saturation, and the method can be also applied for detecting a reservoir and calculating the accurate oil and gas reserves.

Molecular modeling studies of interfacial reactions in wet supercritical CO2.

NASA Astrophysics Data System (ADS)

Glezakou, V.; McGrail, B. P.; Windisch, C. F.; Schaef, H. T.; Martin, P.

2011-12-01

In the recent years, Carbon Capture and Sequestration (CCS) technologies have gained considerable momentum in a globally organized effort to mitigate greenhouse emissions and adverse climate change. Co-sequestration refers to the capture and geologic sequestration of carbon dioxide and minor contaminants (sulfur compounds, NOx, Hg, etc.) in subsurface formations. Cosequestration offers the potential to make carbon management more economically acceptable to industry relative to sequestration of pure CO2. This may be achieved through significant savings in plant (and retrofit) capital cost, operating cost, and energy savings as well by eliminating the need for one or more individual pollutant capture systems (such as SO2 scrubbers). The latter point is important because co-sequestration may result in a net positive impact to the environment through avoided loss of power generation capacity from parasitic loads and reduced fuel needs. This paper will discuss our research on modeling, imaging and characterization of cosequestration processes and reactivity at a fundamental level. Our work examines the interactions of CO2-rich fluids with metal and mineral surfaces, and how these are affected by the presence of other gas components (e.g. SO2, H2O or NOx) commonly present in the CO2 streams. We have found that reactivity is also affected by the composition of the surface or, less obviously, by the surface exposed, for example, (104) vs (100 )of carbonate minerals. We combine experimental techniques such as XRD and Raman spectroscopy, which can detect and follow reactive processes, with ab initio modeling methods based on density functional theory, to establish a reliable correspondence between theory and experiment with predictive capability. Analysis of our molecular dynamics simulations, reveals structural information and vibrational density of states that can directly compare with XRD measurements and vibrational spectroscopy. While reactivity in CO2-containing aqueous environments has been widely studied, the reverse, i.e. reactivity in water-bearing condensed media, is not true. Our simulations show that mechanistic details in these environments can be drastically different, and they are very important in elucidating molecular transformations relevant to CCS or carbon conversion.

Soil organic carbon sequestration and tillage systems in Mediterranean environments

NASA Astrophysics Data System (ADS)

Francaviglia, Rosa; Di Bene, Claudia; Marchetti, Alessandro; Farina, Roberta

2016-04-01

Soil carbon sequestration is of special interest in Mediterranean areas, where rainfed cropping systems are prevalent, inputs of organic matter to soils are low and mostly rely on crop residues, while losses are high due to climatic and anthropic factors such as intensive and non-conservative farming practices. The adoption of reduced or no tillage systems, characterized by a lower soil disturbance in comparison with conventional tillage, has proved to be positively effective on soil organic carbon (SOC) conservation and other physical and chemical processes, parameters or functions, e.g. erosion, compaction, ion retention and exchange, buffering capacity, water retention and aggregate stability. Moreover, soil biological and biochemical processes are usually improved by the reduction of tillage intensity. The work deals with some results available in the scientific literature, and related to field experiment on arable crops performed in Italy, Greece, Morocco and Spain. Data were organized in a dataset containing the main environmental parameters (altitude, temperature, rainfall), soil tillage system information (conventional, minimum and no-tillage), soil parameters (bulk density, pH, particle size distribution and texture), crop type, rotation, management and length of the experiment in years, initial SOCi and final SOCf stocks. Sampling sites are located between 33° 00' and 43° 32' latitude N, 2-860 m a.s.l., with mean annual temperature and rainfall in the range 10.9-19.6° C and 355-900 mm. SOC data, expressed in t C ha-1, have been evaluated both in terms of Carbon Sequestration Rate, given by [(SOCf-SOCi)/length in years], and as percentage change in comparison with the initial value [(SOCf-SOCi)/SOCi*100]. Data variability due to the different environmental, soil and crop management conditions that influence SOC sequestration and losses will be examined.

Comparison of Carbon Sequestration Rates and Energy Balance of Turf in the Denver Urban Ecosystem and an Adjacent Native Grassland

NASA Astrophysics Data System (ADS)

Thienelt, T. S.; Anderson, D. E.; Powell, K. M.

2011-12-01

Urban ecosystems are currently characterized by rapid growth, are expected to continually expand and, thus, represent an important driver of land use change. A significant component of urban ecosystems is lawns, potentially the single largest irrigated "crop" in the U.S. Beginning in March of 2011 (ahead of the growing season), eddy covariance measurements of net carbon exchange and evapotranspiration along with energy balance fluxes were conducted for a well-watered, fertilized lawn (rye-bluegrass-mix) in metropolitan Denver and for a nearby tallgrass prairie (big bluestem, switchgrass, cheatgrass, blue grama). Due to the semi-arid climate conditions of the Denver region, differences in management (i.e., irrigation and fertilization) are expected to have a discernible impact on ecosystem productivity and thus on carbon sequestration rates, evapotranspiration, and the sensible and latent heat partitioning of the energy balance. By mid-July, preliminary data indicated that cumulative evapotranspiration was approximately 270 mm and 170 mm for urban and native grasslands, respectively, although cumulative carbon sequestration at that time was similar for both (approximately 40 mg/m2). However, the pattern of carbon exchange differed between the grasslands. Both sites showed daily net uptake of carbon starting in late May, but the urban lawn displayed greater diurnal variability as well as greater uptake rates in general, especially following fertilization in mid-June. In contrast, the trend of carbon uptake at the prairie site was occasionally reversed following strong convective precipitation events, resulting in a temporary net release of carbon. The continuing acquisition of data and investigation of these relations will help us assess the potential impact of urban growth on regional carbon sequestration.

Dual Agonist Surrobody Simultaneously Activates Death Receptors DR4 and DR5 to Induce Cancer Cell Death.

PubMed

Milutinovic, Snezana; Kashyap, Arun K; Yanagi, Teruki; Wimer, Carina; Zhou, Sihong; O'Neil, Ryann; Kurtzman, Aaron L; Faynboym, Alexsandr; Xu, Li; Hannum, Charles H; Diaz, Paul W; Matsuzawa, Shu-ichi; Horowitz, Michael; Horowitz, Lawrence; Bhatt, Ramesh R; Reed, John C

2016-01-01

Death receptors of the TNF family are found on the surface of most cancer cells and their activation typically kills cancer cells through the stimulation of the extrinsic apoptotic pathway. The endogenous ligand for death receptors 4 and 5 (DR4 and DR5) is TNF-related apoptosis-inducing ligand, TRAIL (Apo2L). As most untransformed cells are not susceptible to TRAIL-induced apoptosis, death receptor activators have emerged as promising cancer therapeutic agents. One strategy to stimulate death receptors in cancer patients is to use soluble human recombinant TRAIL protein, but this agent has limitations of a short half-life and decoy receptor sequestration. Another strategy that attempted to evade decoy receptor sequestration and to provide improved pharmacokinetic properties was to generate DR4 or DR5 agonist antibodies. The resulting monoclonal agonist antibodies overcame the limitations of short half-life and avoided decoy receptor sequestration, but are limited by activating only one of the two death receptors. Here, we describe a DR4 and DR5 dual agonist produced using Surrobody technology that activates both DR4 and DR5 to induce apoptotic death of cancer cells in vitro and in vivo and also avoids decoy receptor sequestration. This fully human anti-DR4/DR5 Surrobody displays superior potency to DR4- and DR5-specific antibodies, even when combined with TRAIL-sensitizing proapoptotic agents. Moreover, cancer cells were less likely to acquire resistance to Surrobody than either anti-DR4 or anti-DR5 monospecific antibodies. Taken together, Surrobody shows promising preclinical proapoptotic activity against cancer cells, meriting further exploration of its potential as a novel cancer therapeutic agent. ©2015 American Association for Cancer Research.

Dual agonist Surrobody™ simultaneously activates death receptors DR4 and DR5 to induce cancer cell death

PubMed Central

Milutinovic, Snezana; Kashyap, Arun K.; Yanagi, Teruki; Wimer, Carina; Zhou, Sihong; O' Neil, Ryann; Kurtzman, Aaron L.; Faynboym, Alexsandr; Xu, Li; Hannum, Charles H.; Diaz, Paul W.; Matsuzawa, Shu-ichi; Horowitz, Michael; Horowitz, Lawrence; Bhatt, Ramesh R.; Reed, John C.

2015-01-01

Death receptors of the Tumor Necrosis Factor (TNF) family are found on surface of most cancer cells and their activation typically kills cancer cells through the stimulation of the extrinsic apoptotic pathway. The endogenous ligand for death receptors-4 and -5 (DR4 and DR5) is Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand, TRAIL (Apo2L). Since most untransformed cells are not susceptible to TRAIL-induced apoptosis, death receptor activators have emerged as promising cancer therapeutic agents. One strategy to stimulate death receptors in cancer patients is to use soluble human recombinant TRAIL protein, but this agent has limitations of a short half-life and decoy receptor sequestration. Another strategy that attempted to evade decoy receptor sequestration and to provide improved pharmacokinetic properties was to generate DR4 or DR5 agonist antibodies. The resulting monoclonal agonist antibodies overcame the limitations of short half-life and avoided decoy receptor sequestration, but are limited by activating only one of the two death receptors. Here, we describe a DR4 and DR5 dual agonist produced using Surrobody™ technology that activates both DR4 and DR5 to induce apoptotic death of cancer cells in vitro and in vivo and also avoids decoy receptor sequestration. This fully human anti-DR4/DR5 Surrobody displays superior potency to DR4- and DR5-specific antibodies, even when combined with TRAIL-sensitizing pro-apoptotic agents. Moreover, cancer cells were less likely to acquire resistance to Surrobody than either anti-DR4 or anti-DR5 mono-specific antibodies. Taken together, Surrobody shows promising preclinical pro-apoptotic activity against cancer cells, meriting further exploration of its potential as a novel cancer therapeutic agent. PMID:26516157

Ultrasonic laboratory measurements of the seismic velocity changes due to CO2 injection

NASA Astrophysics Data System (ADS)

Park, K. G.; Choi, H.; Park, Y. C.; Hwang, S.

2009-04-01

Monitoring the behavior and movement of carbon dioxide (CO2) in the subsurface is a quite important in sequestration of CO2 in geological formation because such information provides a basis for demonstrating the safety of CO2 sequestration. Recent several applications in many commercial and pilot scale projects and researches show that 4D surface or borehole seismic methods are among the most promising techniques for this purpose. However, such information interpreted from the seismic velocity changes can be quite subjective and qualitative without petrophysical characterization for the effect of CO2 saturation on the seismic changes since seismic wave velocity depends on various factors and parameters like mineralogical composition, hydrogeological factors, in-situ conditions. In this respect, we have developed an ultrasonic laboratory measurement system and have carried out measurements for a porous sandstone sample to characterize the effects of CO2 injection to seismic velocity and amplitude. Measurements are done by ultrasonic piezoelectric transducer mounted on both ends of cylindrical core sample under various pressure, temperature, and saturation conditions. According to our fundamental experiments, injected CO2 introduces the decrease of seismic velocity and amplitude. We identified that the velocity decreases about 6% or more until fully saturated by CO2, but the attenuation of seismic amplitude is more drastically than the velocity decrease. We also identified that Vs/Vp or elastic modulus is more sensitive to CO2 saturation. We note that this means seismic amplitude and elastic modulus change can be an alternative target anomaly of seismic techniques in CO2 sequestration monitoring. Thus, we expect that we can estimate more quantitative petrophysical relationships between the changes of seismic attributes and CO2 concentration, which can provide basic relation for the quantitative assessment of CO2 sequestration by further researches.

Geologic CO2 Sequestration: Predicting and Confirming Performance in Oil Reservoirs and Saline Aquifers

NASA Astrophysics Data System (ADS)

Johnson, J. W.; Nitao, J. J.; Newmark, R. L.; Kirkendall, B. A.; Nimz, G. J.; Knauss, K. G.; Ziagos, J. P.

2002-05-01

Reducing anthropogenic CO2 emissions ranks high among the grand scientific challenges of this century. In the near-term, significant reductions can only be achieved through innovative sequestration strategies that prevent atmospheric release of large-scale CO2 waste streams. Among such strategies, injection into confined geologic formations represents arguably the most promising alternative; and among potential geologic storage sites, oil reservoirs and saline aquifers represent the most attractive targets. Oil reservoirs offer a unique "win-win" approach because CO2 flooding is an effective technique of enhanced oil recovery (EOR), while saline aquifers offer immense storage capacity and widespread distribution. Although CO2-flood EOR has been widely used in the Permian Basin and elsewhere since the 1980s, the oil industry has just recently become concerned with the significant fraction of injected CO2 that eludes recycling and is therefore sequestered. This "lost" CO2 now has potential economic value in the growing emissions credit market; hence, the industry's emerging interest in recasting CO2 floods as co-optimized EOR/sequestration projects. The world's first saline aquifer storage project was also catalyzed in part by economics: Norway's newly imposed atmospheric emissions tax, which spurred development of Statoil's unique North Sea Sleipner facility in 1996. Successful implementation of geologic sequestration projects hinges on development of advanced predictive models and a diverse set of remote sensing, in situ sampling, and experimental techniques. The models are needed to design and forecast long-term sequestration performance; the monitoring techniques are required to confirm and refine model predictions and to ensure compliance with environmental regulations. We have developed a unique reactive transport modeling capability for predicting sequestration performance in saline aquifers, and used it to simulate CO2 injection at Sleipner; we are now extending this capability to address CO2-flood EOR/sequestration in oil reservoirs. We have also developed a suite of innovative geophysical and geochemical techniques for monitoring sequestration performance in both settings. These include electromagnetic induction imaging and electrical resistance tomography for tracking migration of immiscible CO2, noble gas isotopes for assessing trace CO2 leakage through the cap rock, and integrated geochemical sampling, analytical, and experimental methods for determining sequestration partitioning among solubility and mineral trapping mechanisms. We have proposed to demonstrate feasibility of the co-optimized EOR/sequestration concept and utility of our modeling and monitoring technologies to design and evaluate its implementation by conducting a demonstration project in the Livermore Oil Field. This small, mature, shallow field, located less than a mile east of Lawrence Livermore National Laboratory, is representative of many potential EOR/sequestration sites in California. In approach, this proposed demonstration is analogous to the Weyburn EOR/CO2 monitoring project, to which it will provide an important complement by virtue of its contrasting depth (immiscible versus Weyburn's miscible CO2 flood) and geologic setting (clay-capped sand versus Weyburn's anhydrite-capped carbonate reservoir).

Basin-Scale Leakage Risks from Geologic Carbon Sequestration: Impact on Carbon Capture and Storage Energy Market Competitiveness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peters, Catherine; Fitts, Jeffrey; Wilson, Elizabeth

This three-year project, performed by Princeton University in partnership with the University of Minnesota and Brookhaven National Laboratory, examined geologic carbon sequestration in regard to CO{sub 2} leakage and potential subsurface liabilities. The research resulted in basin-scale analyses of CO{sub 2} and brine leakage in light of uncertainties in the characteristics of leakage processes, and generated frameworks to monetize the risks of leakage interference with competing subsurface resources. The geographic focus was the Michigan sedimentary basin, for which a 3D topographical model was constructed to represent the hydrostratigraphy. Specifically for Ottawa County, a statistical analysis of the hydraulic properties ofmore » underlying sedimentary formations was conducted. For plausible scenarios of injection into the Mt. Simon sandstone, leakage rates were estimated and fluxes into shallow drinking-water aquifers were found to be less than natural analogs of CO{sub 2} fluxes. We developed the Leakage Impact Valuation (LIV) model in which we identified stakeholders and estimated costs associated with leakage events. It was found that costs could be incurred even in the absence of legal action or other subsurface interference because there are substantial costs of finding and fixing the leak and from injection interruption. We developed a model framework called RISCS, which can be used to predict monetized risk of interference with subsurface resources by combining basin-scale leakage predictions with the LIV method. The project has also developed a cost calculator called the Economic and Policy Drivers Module (EPDM), which comprehensively calculates the costs of carbon sequestration and leakage, and can be used to examine major drivers for subsurface leakage liabilities in relation to specific injection scenarios and leakage events. Finally, we examined the competiveness of CCS in the energy market. This analysis, though qualitative, shows that financial incentives, such as a carbon tax, are needed for coal combustion with CCS to gain market share. In another part of the project we studied the role of geochemical reactions in affecting the probability of CO{sub 2} leakage. A basin-scale simulation tool was modified to account for changes in leakage rates due to permeability alterations, based on simplified mathematical rules for the important geochemical reactions between acidified brines and caprock minerals. In studies of reactive flows in fractured caprocks, we examined the potential for permeability increases, and the extent to which existing reactive transport models would or would not be able to predict it. Using caprock specimens from the Eau Claire and Amherstburg, we found that substantial increases in permeability are possible for caprocks that have significant carbonate content, but minimal alteration is expected otherwise. We also found that while the permeability increase may be substantial, it is much less than what would be predicted from hydrodynamic models based on mechanical aperture alone because the roughness that is generated tends to inhibit flow.« less

In the Middle of Nowhere: How a Textbook Can Position the Mathematics Learner

ERIC Educational Resources Information Center

Herbel-Eisenmann, Beth; Wagner, David

2005-01-01

We outline a framework for investigating how a mathematics textbook positions the mathematics learner. We use tools and concepts from discourse analysis, a field of linguistic scholarship, to illustrate the ways in which a textbook can position people in relation to mathematics and how the text can position the mathematics learner in relation to…

Secondary Teachers’ Mathematics-related Beliefs and Knowledge about Mathematical Problem-solving

NASA Astrophysics Data System (ADS)

E Siswono, T. Y.; Kohar, A. W.; Hartono, S.

2017-02-01

This study investigates secondary teachers’ belief about the three mathematics-related beliefs, i.e. nature of mathematics, teaching mathematics, learning mathematics, and knowledge about mathematical problem solving. Data were gathered through a set of task-based semi-structured interviews of three selected teachers with different philosophical views of teaching mathematics, i.e. instrumental, platonist, and problem solving. Those teachers were selected from an interview using a belief-related task from purposively selected teachers in Surabaya and Sidoarjo. While the interviews about knowledge examine teachers’ problem solving content and pedagogical knowledge, the interviews about beliefs examine their views on several cases extracted from each of such mathematics-related beliefs. Analysis included the categorization and comparison on each of beliefs and knowledge as well as their interaction. Results indicate that all the teachers did not show a high consistency in responding views of their mathematics-related beliefs, while they showed weaknesses primarily on problem solving content knowledge. Findings also point out that teachers’ beliefs have a strong relationship with teachers’ knowledge about problem solving. In particular, the instrumental teacher’s beliefs were consistent with his insufficient knowledge about problem-solving, while both platonist and problem-solving teacher’s beliefs were consistent with their sufficient knowledge of either content or pedagogical problem solving.

Why do early mathematics skills predict later reading? The role of mathematical language.

PubMed

Purpura, David J; Logan, Jessica A R; Hassinger-Das, Brenna; Napoli, Amy R

2017-09-01

A growing body of evidence indicates that the development of mathematics and literacy skills is highly related. The importance of literacy skills-specifically language-for mathematics development has been well rationalized. However, despite several prominent studies indicating that mathematics skills are highly predictive of literacy development, the reason for this relation is not well understood. The purpose of this study was to identify how and why early mathematics is predictive of early literacy development. Participants included 125 preschool children 3-5 years old (M = 4 years 3 months). Participants were assessed on mathematics, literacy, and cognitive measures in both the fall and spring of their preschool year. Mediation analyses indicated that the relation between early mathematics and literacy skills is mediated by children's mathematical language skills. These findings suggest that, in prior research identifying mathematical performance as a significant predictor of later literacy skills, mathematical performance may have acted only as a proxy measure for more complex language skills such as those assessed on a mathematical language measure. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The co-development and interrelation of proof and authority: The case of Yana and Ronit

NASA Astrophysics Data System (ADS)

Fried, Michael N.; Amit, Miriam

2008-12-01

Students' mathematical lives are characterized not only by a set of mathematical ideas and the engagement in mathematical thinking, but also by social relations, specifically, relations of authority. Watching student actions and speaking to students, one becomes cognizant of a `web of authority' ever present in mathematics classrooms. In past work, it has been shown how those relations of authority may sometimes interfere with students' reflecting on mathematical ideas. However, "…by shifting the emphasis from domination and obedience to negotiation and consent…" (Amit & Fried, 2005, p.164) it has also been stressed that these relations are fluid and are, in fact, a sine qua non in the process of students' defining their place in a mathematical community. But can these fluid relations be operative also in the formation of specific mathematical ideas? It is my contention that they may at least coincide with students' thinking about one significant mathematical idea, namely, the idea of proof. In this talk, I shall discuss both the general question of authority in the mathematics classroom and its specific connection with students' thinking about proof in the context of work done in two 8th grade classrooms.

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees.

PubMed

Zhao, Chang; Sander, Heather A

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration.

Effects of conventional and a novel colonic-release bile acid sequestrant, A3384, on fibroblast growth factor 19 and bile acid metabolism in healthy volunteers and patients with bile acid diarrhoea.

PubMed

Appleby, R N; Bajor, A; Gillberg, P-G; Graffner, H; Simrén, M; Ung, K A; Walters, Jrf

2017-04-01

Primary bile acid diarrhoea (BAD) is associated with increased bile acid synthesis and low fibroblast growth factor 19 (FGF19). Bile acid sequestrants are used as therapy, but are poorly tolerated and may exacerbate FGF19 deficiency. The purpose of this study was to evaluate the pharmacological effects of conventional sequestrants and a colonic-release formulation preparation of colestyramine (A3384) on bile acid metabolism and bowel function in patients with BAD. Patients with seven-day 75 selenium-homocholic acid taurine (SeHCAT) scan retention <10% were randomised in a double-blind protocol to two weeks treatment with twice-daily A3384 250 mg ( n  = 6), 1 g ( n  = 7) or placebo ( n  = 6). Thirteen patients were taking conventional sequestrants at the start of the study. Symptoms were recorded and serum FGF19 and 7α-hydroxy-4-cholesten-3-one (C4) measured. Median serum FGF19 on conventional sequestrant treatment was 28% lower than baseline values in BAD ( p  < 0.05). C4 on conventional sequestrant treatment was 58% higher in BAD ( p  < 0.001). No changes were seen on starting or withdrawing A3384. A3384 improved diarrhoeal symptoms, with a median reduction of 2.2 points on a 0-10 Likert scale compared to placebo, p  < 0.05. Serum FGF19 was suppressed and bile acid production up-regulated on conventional bile acid sequestrants, but not with A3384. This colonic-release formulation of colestyramine produced symptomatic benefit in patients with BAD.

Effects of conventional and a novel colonic-release bile acid sequestrant, A3384, on fibroblast growth factor 19 and bile acid metabolism in healthy volunteers and patients with bile acid diarrhoea

PubMed Central

Bajor, A; Gillberg, P-G; Graffner, H; Simrén, M; Ung, KA; Walters, JRF

2016-01-01

Background Primary bile acid diarrhoea (BAD) is associated with increased bile acid synthesis and low fibroblast growth factor 19 (FGF19). Bile acid sequestrants are used as therapy, but are poorly tolerated and may exacerbate FGF19 deficiency. Aim The purpose of this study was to evaluate the pharmacological effects of conventional sequestrants and a colonic-release formulation preparation of colestyramine (A3384) on bile acid metabolism and bowel function in patients with BAD. Methods Patients with seven-day 75selenium-homocholic acid taurine (SeHCAT) scan retention <10% were randomised in a double-blind protocol to two weeks treatment with twice-daily A3384 250 mg (n = 6), 1 g (n = 7) or placebo (n = 6). Thirteen patients were taking conventional sequestrants at the start of the study. Symptoms were recorded and serum FGF19 and 7α-hydroxy-4-cholesten-3-one (C4) measured. Results Median serum FGF19 on conventional sequestrant treatment was 28% lower than baseline values in BAD (p < 0.05). C4 on conventional sequestrant treatment was 58% higher in BAD (p < 0.001). No changes were seen on starting or withdrawing A3384. A3384 improved diarrhoeal symptoms, with a median reduction of 2.2 points on a 0–10 Likert scale compared to placebo, p < 0.05. Conclusions Serum FGF19 was suppressed and bile acid production up-regulated on conventional bile acid sequestrants, but not with A3384. This colonic-release formulation of colestyramine produced symptomatic benefit in patients with BAD. PMID:28507750

The interconnectedness between landowner knowledge, value, belief, attitude, and willingness to act: policy implications for carbon sequestration on private rangelands.

PubMed

Cook, Seth L; Ma, Zhao

2014-02-15

Rangelands can be managed to increase soil carbon and help mitigate emissions of carbon dioxide. This study assessed Utah rangeland owner's environmental values, beliefs about climate change, and awareness of and attitudes towards carbon sequestration, as well as their perceptions of potential policy strategies for promoting carbon sequestration on private rangelands. Data were collected from semi-structured interviews and a statewide survey of Utah rangeland owners, and were analyzed using descriptive and bivariate statistics. Over two-thirds of respondents reported some level of awareness of carbon sequestration and a generally positive attitude towards it, contrasting to their lack of interest in participating in a relevant program in the future. Having a positive attitude was statistically significantly associated with having more "biocentric" environmental values, believing the climate had been changing over the past 30 years, and having a stronger belief of human activities influencing the climate. Respondents valued the potential ecological benefits of carbon sequestration more than the potential financial or climate change benefits. Additionally, respondents indicated a preference for educational approaches over financial incentives. They also preferred to work with a private agricultural entity over a non-profit or government entity on improving land management practices to sequester carbon. These results suggest potential challenges for developing technically sound and socially acceptable policies and programs for promoting carbon sequestration on private rangelands. Potential strategies for overcoming these challenges include emphasizing the ecological benefits associated with sequestering carbon to appeal to landowners with ecologically oriented management objectives, enhancing the cooperation between private agricultural organizations and government agencies, and funneling resources for promoting carbon sequestration into existing land management and conservation programs that may produce carbon benefits. Copyright © 2014 Elsevier Ltd. All rights reserved.

Potential restrictions for CO2 sequestration sites due to shale and tight gas production.

PubMed

Elliot, T R; Celia, M A

2012-04-03

Carbon capture and geological sequestration is the only available technology that both allows continued use of fossil fuels in the power sector and reduces significantly the associated CO(2) emissions. Geological sequestration requires a deep permeable geological formation into which captured CO(2)can be injected, and an overlying impermeable formation, called a caprock, that keeps the buoyant CO(2) within the injection formation. Shale formations typically have very low permeability and are considered to be good caprock formations. Production of natural gas from shale and other tight formations involves fracturing the shale with the explicit objective to greatly increase the permeability of the shale. As such, shale gas production is in direct conflict with the use of shale formations as a caprock barrier to CO(2) migration. We have examined the locations in the United States where deep saline aquifers, suitable for CO(2) sequestration, exist, as well as the locations of gas production from shale and other tight formations. While estimated sequestration capacity for CO(2) sequestration in deep saline aquifers is large, up to 80% of that capacity has areal overlap with potential shale-gas production regions and, therefore, could be adversely affected by shale and tight gas production. Analysis of stationary sources of CO(2) shows a similar effect: about two-thirds of the total emissions from these sources are located within 20 miles of a deep saline aquifer, but shale and tight gas production could affect up to 85% of these sources. These analyses indicate that colocation of deep saline aquifers with shale and tight gas production could significantly affect the sequestration capacity for CCS operations. This suggests that a more comprehensive management strategy for subsurface resource utilization should be developed.

Land-use changes and carbon sequestration through the twentieth century in a Mediterranean mountain ecosystem: implications for land management.

PubMed

Padilla, Francisco M; Vidal, Beatriz; Sánchez, Joaquín; Pugnaire, Francisco I

2010-12-01

Ecosystems in the western Mediterranean basin have undergone intense changes in land use throughout the centuries, resulting in areas with severe alterations. Today, most these areas have become sensitive to human activity, prone to profound changes in land-use configuration and ecosystem services. A consensus exists amongst stakeholders that ecosystem services must be preserved but managerial strategies that help to preserve them while ensuring sustainability are often inadequate. To provide a basis for measuring implications of land-use change on carbon sequestration services, changes in land use and associated carbon sequestration potential throughout the 20th century in a rural area at the foothills of the Sierra Nevada range (SE Spain) were explored. We found that forest systems replaced dryland farming and pastures from the middle of the century onwards as a result of agricultural abandonment and afforestation programs. The area has always acted as a carbon sink with sequestration rates ranging from 28,961 t CO(2) year(-1) in 1921 to 60,635 t CO(2) year(-1) in 1995, mirroring changes in land use. Conversion from pastures to woodland, for example, accounted for an increase in carbon sequestration above 30,000 t CO(2) year(-1) by the end of the century. However, intensive deforestation would imply a decrease of approximately 66% of the bulk CO(2) fixed. In our study area, woodland conservation is essential to maintain the ecosystem services that underlie carbon sequestration. Our essay could inspire policymakers to better achieve goals of increasing carbon sequestration rates and sustainability within protected areas. Copyright © 2010 Elsevier Ltd. All rights reserved.

Time-Lapse Seismic Monitoring and Performance Assessment of CO 2 Sequestration in Hydrocarbon Reservoirs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Datta-Gupta, Akhil

Carbon dioxide sequestration remains an important and challenging research topic as a potentially viable approach for mitigating the effects of greenhouse gases on global warming (e.g., Chu and Majumdar, 2012; Bryant, 2007; Orr, 2004; Hepple and Benson, 2005; Bachu, 2003; Grimston et al., 2001). While CO 2 can be sequestered in oceanic or terrestrial biomass, the most mature and effective technology currently available is sequestration in geologic formations, especially in known hydrocarbon reservoirs (Barrufet et al., 2010; Hepple and Benson, 2005). However, challenges in the design and implementation of sequestration projects remain, especially over long time scales. One problem ismore » that the tendency for gravity override caused by the low density and viscosity of CO 2. In the presence of subsurface heterogeneity, fractures and faults, there is a significant risk of CO 2 leakage from the sequestration site into overlying rock compared to other liquid wastes (Hesse and Woods, 2010; Ennis-King and Patterson, 2002; Tsang et al., 2002). Furthermore, the CO 2 will likely interact chemically with the rock in which it is stored, so that understanding and predicting its transport behavior during sequestration can be complex and difficult (Mandalaparty et al., 2011; Pruess et al., 2003). Leakage of CO 2 can lead to such problems as acidification of ground water and killing of plant life, in addition to contamination of the atmosphere (Ha-Duong, 2003; Gasda et al., 2004). The development of adequate policies and regulatory systems to govern sequestration therefore requires improved characterization of the media in which CO 2 is stored and the development of advanced methods for detecting and monitoring its flow and transport in the subsurface (Bachu, 2003).« less

Pulmonary Sequestration: Early Diagnosis and Management

PubMed Central

Wani, Sajad A.; Mufti, Gowher N.; Bhat, Nisar A.; Baba, Ajaz A.

2015-01-01

Intralobar sequestration is characterized by aberrant formation of nonfunctional lung tissue that has no communication with the bronchial tree and receives systemic arterial blood supply. Failure of earlier diagnosis can lead to recurrent pneumonia, failure to thrive, multiple hospital admissions, and more morbidity. The aim of this case report is to increase the awareness about the lung sequestration, to diagnose and treat it early, so that it is resected before repeated infection, and prevent the morbidity and mortality. PMID:26273485

Heart Failure in a Preterm Infant. Case Report and Echocardiographic Clues for the Diagnostic Approach to Pulmonary Sequestration.

PubMed

Rodriguez-Gonzalez, Moises; Segado-Arenas, Antonio; Matamala-Morillo, Miguel A

2016-08-01

Pulmonary sequestration is an unusual cause of heart failure in infants. We report a preterm newborn with signs of congestive heart failure supposed secondary to a ductus arteriosus that was finally diagnosed as a coexistent extralobar pulmonary sequestration. In this case, Doppler echocardiography was essential for diagnosis, revealing an abnormal systemic arterial supply to the sequestered lung and abnormal venous drainage. © 2016, Wiley Periodicals, Inc.

Ensuring a Strong U.S. Defense for the Future: The National Defense Panel Review of the 2014 Quadrennial Defense Review

DTIC Science & Technology

2014-07-31

began declining before partial sequestration, which has only worsened the problem. When automatic budget cuts took effect in April 2013 for three...structures, including the BUR force, the 2002 Force, the QDR force, and the sequestration force. Table 1 (Appendix A) contains a comparison of these...to address those same security challenges. Under the BCA, automatic reductions of the caps on Government-wide discretionary funding (sequestration

A Review of CO2 Sequestration Projects and Application in China

PubMed Central

Tang, Yong; Yang, Ruizhi; Bian, Xiaoqiang

2014-01-01

In 2008, the top CO2 emitters were China, United States, and European Union. The rapid growing economy and the heavy reliance on coal in China give rise to the continued growth of CO2 emission, deterioration of anthropogenic climate change, and urgent need of new technologies. Carbon Capture and sequestration is one of the effective ways to provide reduction of CO2 emission and mitigation of pollution. Coal-fired power plants are the focus of CO2 source supply due to their excessive emission and the energy structure in China. And over 80% of the large CO2 sources are located nearby storage reservoirs. In China, the CO2 storage potential capacity is of about 3.6 × 109 t for all onshore oilfields; 30.483 × 109 t for major gas fields between 900 m and 3500 m of depth; 143.505 × 109 t for saline aquifers; and 142.67 × 109 t for coal beds. On the other hand, planation, soil carbon sequestration, and CH4–CO2 reforming also contribute a lot to carbon sequestration. This paper illustrates some main situations about CO2 sequestration applications in China with the demonstration of several projects regarding different ways of storage. It is concluded that China possesses immense potential and promising future of CO2 sequestration. PMID:25302323

CCS Activities Being Performed by the U.S. DOE

PubMed Central

Dressel, Brian; Deel, Dawn; Rodosta, Traci; Plasynski, Sean; Litynski, John; Myer, Larry

2011-01-01

The United States Department of Energy (DOE) is the lead federal agency for the development and deployment of carbon sequestration technologies. Its mission includes promoting scientific and technological innovations and transfer of knowledge for safe and permanent storage of CO2 in the subsurface. To accomplish its mission, DOE is characterizing and classifying potential geologic storage reservoirs in basins throughout the U.S. and Canada, and developing best practices for project developers, to help ensure the safety of future geologic storage projects. DOE’s Carbon Sequestration Program, Regional Carbon Sequestration Partnership (RCSP) Initiative, administered by the National Energy Technology Laboratory (NETL), is identifying, characterizing, and testing potential injection formations. The RCSP Initiative consists of collaborations among government, industry, universities, and international organizations. Through this collaborative effort, a series of integrated knowledge-based tools have been developed to help potential sequestration project developers. They are the Carbon Sequestration Atlas of the United States and Canada, National Carbon Sequestration Database and Geographic System (NATCARB), and best practice manuals for CCS including Depositional Reservoir Classification for CO2; Public Outreach and Education for Carbon Storage Projects; Monitoring, Verification, and Accounting of CO2 Stored in Deep Geologic Formation; Site Screening, Site Selection, and Initial Characterization of CO2 Storage in Deep Geologic Formations. DOE’s future research will help with refinement of these tools and additional best practice manuals (BPM) which focus on other technical aspects of project development. PMID:21556188

In Vitro Assessment of Uptake and Lysosomal Sequestration of Respiratory Drugs in Alveolar Macrophage Cell Line NR8383.

PubMed

Ufuk, Ayşe; Somers, Graham; Houston, J Brian; Galetin, Aleksandra

2015-12-01

To assess accumulation and lysosomal sequestration of 9 drugs used in respiratory indications (plus imipramine as positive control) in the alveolar macrophage (AM) cell line NR8383. For all drugs, uptake at 5 μM was investigated at 37 and 4°C to delineate active uptake and passive diffusion processes. Accumulation of basic clarithromycin, formoterol and imipramine was also assessed over 0.1-100 μM concentration range. Lysosomal sequestration was investigated using ammonium chloride (NH4Cl), monensin and nigericin. Impact of lysosomal sequestration on clarithromycin accumulation kinetics was investigated. Both cell-to-medium concentration ratio (Kp) and uptake clearance (CLuptake) ranged > 400-fold for the drugs investigated. The greatest Kp was observed for imipramine (391) and clarithromycin (82), in contrast to no accumulation seen for terbutaline. A concentration-dependent accumulation was evident for the basic drugs investigated. Imipramine and clarithromycin Kp and CLuptake were reduced by 59-85% in the presence of NH4Cl and monensin/nigericin, indicating lysosomal accumulation, whereas lysosomal sequestration was not pronounced for the other 8 respiratory drugs. Clarithromycin uptake rate was altered by NH4Cl, highlighting the impact of subcellular distribution on accumulation kinetics. This study provides novel evidence of the utility of NR8383 for investigating accumulation and lysosomal sequestration of respiratory drugs in AMs.

Mathematics beliefs and achievement of a national sample of Native American students: results from the Trends in International Mathematics and Science Study (TIMSS) 2003 United States assessment.

PubMed

House, J Daniel

2009-04-01

Recent mathematics assessment findings indicate that Native American students tend to score below students of the ethnic majority. Findings suggest that students' beliefs about mathematics are significantly related to achievement outcomes. This study examined relations between self-beliefs and mathematics achievement for a national sample of 130 Grade 8 Native American students from the Trends in International Mathematics and Science Study (TIMSS) 2003 United States sample of (M age = 14.2 yr., SD = 0.5). Multiple regression indicated several significant relations of mathematics beliefs with achievement and accounted for 26.7% of the variance in test scores. Students who earned high test scores tended to hold more positive beliefs about their ability to learn mathematics quickly, while students who earned low scores expressed negative beliefs about their ability to learn new mathematics topics.

Evaluation of factors affecting soil carbon sequestration services of stormwater wet retention ponds in varying climate zones.

PubMed

Merriman, L S; Moore, T L C; Wang, J W; Osmond, D L; Al-Rubaei, A M; Smolek, A P; Blecken, G T; Viklander, M; Hunt, W F

2017-04-01

The carbon sequestration services of stormwater wet retention ponds were investigated in four different climates: U.S., Northern Sweden, Southern Sweden, and Singapore, representing a range of annual mean temperatures, growing season lengths and rainfall depths: geographic factors that were not statistically compared, but have great effect on carbon (C) accumulation. A chronosequence was used to estimate C accumulations rates; C accumulation and decomposition rates were not directly measured. C accumulated significantly over time in vegetated shallow water areas (0-30cm) in the USA (78.4gCm -2 yr -1 ), in vegetated temporary inundation zones in Sweden (75.8gCm -2 yr -1 ), and in all ponds in Singapore (135gCm -2 yr -1 ). Vegetative production appeared to exert a stronger influence on relative C accumulation rates than decomposition. Comparing among the four climatic zones, the effects of increasing rainfall and growing season lengths (vegetative production) outweighed the effects of higher temperature on decomposition rates. Littoral vegetation was a significant source to the soil C pool relative to C sources draining from watersheds. Establishment of vegetation in the shallow water zones of retention ponds is vital to providing a C source to the soil. Thus, the width of littoral shelves containing this vegetation along the perimeter may be increased if C sequestration is a design goal. This assessment establishes that stormwater wet retention ponds can sequester C across different climate zones with generally annual rainfall and lengths of growing season being important general factors for C accumulation. Copyright © 2017 Elsevier B.V. All rights reserved.

Recent organic carbon sequestration in the shelf sediments of the Bohai Sea and Yellow Sea, China

NASA Astrophysics Data System (ADS)

Hu, Limin; Shi, Xuefa; Bai, Yazhi; Qiao, Shuqing; Li, Li; Yu, Yonggui; Yang, Gang; Ma, Deyi; Guo, Zhigang

2016-03-01

This study provides an extensive depiction of regional scale sedimentary total organic carbon (TOC) sequestration in the Bohai Sea (BS) and Yellow Sea (YS), marginal system of the western Pacific Ocean. The spatial pattern of the sediment mass accumulation rate (MAR) in the BS and YS was summarized based on a 100-year timescale. The relatively higher MAR (3 - 7 g/cm2/y) in the Yellow River estuary, compared to the adjacent areas, indicate a predominant impact of river discharge on the modern sedimentation process in the BS. Relatively stable sedimentary environment in the offshore mud deposits of the BS and YS was also identified based on the along-core sediment composition and radionuclides profiles. The corresponding spatial pattern of grain size and TOC content suggest a hydrodynamic constraint on the sedimentary TOC accumulation. Moreover, in spite of the various TOC sources revealed by the bulk organic matter (OM) proxies (C/N ratio and δ13C), the restriction of these bulk parameters with potential masking of the signature of terrigenous OM was also identified. The average burial flux of TOC (15.3 g C/m2/y) was finally obtained with a total sequestration of 5.6 × 106 t C/y, suggesting that the BS and YS serve as a significant repository of sedimentary TOC. The overall organic carbon storage capacity of the BS and YS is mainly sustained by the fluvial/land-based OM input, high phytoplankton primary productivity, convergent hydrodynamic and stable depositional settings.

Granulocyte Macrophage-Colony Stimulating Factor-induced Zn Sequestration Enhances Macrophage Superoxide and Limits Intracellular Pathogen Survival

PubMed Central

Vignesh, Kavitha Subramanian; Landero Figueroa, Julio A.; Porollo, Aleksey; Caruso, Joseph A.; Deepe, George S.

2013-01-01

SUMMARY Macrophages possess numerous mechanisms to combat microbial invasion, including sequestration of essential nutrients, like Zn. The pleiotropic cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) enhances antimicrobial defenses against intracellular pathogens such as Histoplasma capsulatum, but its mode of action remains elusive. We have found that GM-CSF activated infected macrophages sequestered labile Zn by inducing binding to metallothioneins (MTs) in a STAT3 and STAT5 transcription factor-dependent manner. GM-CSF upregulated expression of Zn exporters, Slc30a4 and Slc30a7 and the metal was shuttled away from phagosomes and into the Golgi apparatus. This distinctive Zn sequestration strategy elevated phagosomal H+ channel function and triggered reactive oxygen species (ROS) generation by NADPH oxidase. Consequently, H. capsulatum was selectively deprived of Zn, thereby halting replication and fostering fungal clearance. GM-CSF mediated Zn sequestration via MTs in vitro and in vivo in mice and in human macrophages. These findings illuminate a GM-CSF-induced Zn-sequestration network that drives phagocyte antimicrobial effector function. PMID:24138881

HIV internalization into oral and genital epithelial cells by endocytosis and macropinocytosis leads to viral sequestration in the vesicles

PubMed Central

Yasen, Aizezi; Herrera, Rossana; Rosbe, Kristina; Lien, Kathy; Tugizov, Sharof M.

2018-01-01

Recently, we showed that HIV-1 is sequestered, i.e., trapped, in the intracellular vesicles of oral and genital epithelial cells. Here, we investigated the mechanisms of HIV-1 sequestration in vesicles of polarized tonsil, foreskin and cervical epithelial cells. HIV-1 internalization into epithelial cells is initiated by multiple entry pathways, including clathrin-, caveolin/lipid raft-associated endocytosis and macropinocytosis. Inhibition of HIV-1 attachment to galactosylceramide and heparan sulfate proteoglycans, and virus endocytosis and macropinocytosis reduced HIV-1 sequestration by 30–40%. T-cell immunoglobulin and mucin domain 1 (TIM-1) were expressed on the apical surface of polarized tonsil, cervical and foreskin epithelial cells. However, TIM-1-associated HIV-1 macropinocytosis and sequestration were detected mostly in tonsil epithelial cells. Sequestered HIV-1 was resistant to trypsin, pronase, and soluble CD4, indicating that the sequestered virus was intracellular. Inhibition of HIV-1 intraepithelial sequestration and elimination of vesicles containing virus in the mucosal epithelium may help in the prevention of HIV-1 mucosal transmission. PMID:29277006

An Analysis of the Climate Change Mitigation Potential through Soil Organic Carbon Sequestration in a Corn Belt Watershed.

PubMed

Bhattarai, Mukesh Dev; Secchi, Silvia; Schoof, Justin

2017-01-01

Land-based carbon sequestration constitutes a major low cost and immediately viable option in climate change mitigation. Using downscaled data from eight atmosphere-ocean general circulation models for a simulation period between 2015 and 2099, we examine the carbon sequestration potential of alternative agricultural land uses in an intensively farmed Corn Belt watershed and the impact of climate change on crop yields. Our results show that switching from conventional tillage continuous corn to no-till corn-soybean can sequester the equivalent of 192.1 MtCO 2 eq of soil organic carbon per hectare with a sequestration rate of 2.26 MtCO 2 eq ha -1 yr -1 . Our results also indicate that switchgrass can sequester the equivalent of 310.7 MtCO 2 eq of soil organic carbon per hectare with a sequestration rate of 3.65 MtCO 2 eq ha -1 yr -1 . Our findings suggest that, unlike for corn and soybean yields, climate change does not have a significant effect on switchgrass yields, possibly due to the carbon fertilization effect.

Development and Implementation of the Midwest Geological Sequestration Consortium CO 2-Technology Transfer Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenberg, Sallie E.

2015-06-30

In 2009, the Illinois State Geological Survey (ISGS), in collaboration with the Midwest Geological Sequestration Consortium (MGSC), created a regional technology training center to disseminate carbon capture and sequestration (CCS) technology gained through leadership and participation in regional carbon sequestration projects. This technology training center was titled and branded as the Sequestration Training and Education Program (STEP). Over the last six years STEP has provided local, regional, national, and international education and training opportunities for engineers, geologists, service providers, regulators, executives, K-12 students, K-12 educators, undergraduate students, graduate students, university and community college faculty members, and participants of community programsmore » and functions, community organizations, and others. The goal for STEP educational programs has been on knowledge sharing and capacity building to stimulate economic recovery and development by training personnel for commercial CCS projects. STEP has worked with local, national and international professional organizations and regional experts to leverage existing training opportunities and provide stand-alone training. This report gives detailed information on STEP activities during the grant period (2009-2015).« less

An Analysis of the Climate Change Mitigation Potential through Soil Organic Carbon Sequestration in a Corn Belt Watershed

NASA Astrophysics Data System (ADS)

Bhattarai, Mukesh Dev; Secchi, Silvia; Schoof, Justin

2017-01-01

Land-based carbon sequestration constitutes a major low cost and immediately viable option in climate change mitigation. Using downscaled data from eight atmosphere-ocean general circulation models for a simulation period between 2015 and 2099, we examine the carbon sequestration potential of alternative agricultural land uses in an intensively farmed Corn Belt watershed and the impact of climate change on crop yields. Our results show that switching from conventional tillage continuous corn to no-till corn-soybean can sequester the equivalent of 192.1 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 2.26 MtCO2 eq ha-1 yr-1. Our results also indicate that switchgrass can sequester the equivalent of 310.7 MtCO2 eq of soil organic carbon per hectare with a sequestration rate of 3.65 MtCO2 eq ha-1 yr-1. Our findings suggest that, unlike for corn and soybean yields, climate change does not have a significant effect on switchgrass yields, possibly due to the carbon fertilization effect.

Atmospheric CO2 sequestration in iron and steel slag: Consett, Co. Durham, UK.

PubMed

Mayes, William Matthew; Riley, Alex L; Gomes, Helena I; Brabham, Peter; Hamlyn, Joanna; Pullin, Huw; Renforth, Phil

2018-06-12

Carbonate formation in waste from the steel industry could constitute a non-trivial proportion of global requirements to remove carbon dioxide from the atmosphere at potentially low cost. To constrain this potential, we examined atmospheric carbon dioxide sequestration in a >20 million tonne legacy slag deposit in northern England, UK. Carbonates formed from the drainage water of the heap had stable carbon and oxygen isotopes between -12 and -25 ‰ and -5 and -18 ‰ for δ13C and δ18O respectively, suggesting atmospheric carbon dioxide sequestration in high pH solutions. From analysis of solution saturation state, we estimate that between 280 and 2,900 tCO2 have precipitated from the drainage waters. However, by combining a thirty-seven-year dataset of the drainage water chemistry with geospatial analysis, we estimate that <1 % of the maximum carbon capture potential of the deposit may have been realised. This implies that uncontrolled deposition of slag is insufficient to maximise carbon sequestration, and there may be considerable quantities of unreacted legacy deposits available for atmospheric carbon sequestration.

Implications of changes in tropical shifting cultivation intensification on land productivity and GHG-related biogeochemistry

NASA Astrophysics Data System (ADS)

Bustier, Bernard; Ngoy, Alfred; Pietsch, Stephan; Mosnier, Aline

2017-04-01

Traditional shifting cultivation used to be a sustainable type of land use for the subsistence of populations in tropical rainforests. The vast resource of moist tropical forests together with low population densities allowed for long fallow periods on sparsely distributed slash and burn parcels with large areas of untouched forest in between. Population growth and concomitant increase in land demand for subsistence as well as increasing infrastructure development for commercial forestry, cash crops and mining, however, altered the picture over recent decades. As a result, fallow periods were reduced due to lack of pristine land. In this study we use field data and modeling results from the Congo Basin to assess the impacts of reduced fallow periods on Carbon sequestration dynamics using a BGC model calibrated and validated with > 150 research plots distributed over the western Congo Basin and representing different management and land use histories. We find that the average carbon sequestration rate reduces over the number of cultivation cycles and that a reduction of the fallow from 10 years to 7 years reduce the average carbon sequestration between 13 and 21% and from 7 years to 4 years between 23 and 29% depending on soil fertility. Results will be discussed in the context of population growth and changes in environmetal conditions.

Environmental drivers of deadwood dynamics in woodlands and forests

Treesearch

M. Garbarino; R. Marzano; John Shaw; J. N. Long

2015-01-01

Deadwood dynamics play a key role in many forest ecosystems. Understanding the mechanisms involved in the accumulation and depletion of deadwood can enhance our understanding of fundamental processes such as carbon sequestration and disturbance regimes, allowing better predictions of future changes related to alternative management and climate scenarios. A...

Overview of global climate change and carbon sequestration

Treesearch

Kurt Johnsen

2004-01-01

The potential influence of global climate change on southern forests is uncertain. Outputs of climate change models differ considerably in their projections for precipitation and other variables that affect forests. Forest responses, particularly effects on competition among species, are difficult to assess. Even the responses of relatively simple ecosystems, such as...

Calibration of the soil conditioning index (SCI) to soil organic carbon in the southeastern USA

USDA-ARS?s Scientific Manuscript database

Prediction of soil organic C sequestration with adoption of various conservation agricultural management approaches is needed to meet the emerging market for environmental services provided by agricultural land stewardship. The soil conditioning index (SCI) is a relatively simple model used by the ...

Australasian sequestrate fungi 17: the genus Hydnoplicata (Ascomycota, Pezizaceae) resurrected.

Treesearch

James M. Trappe; Andrew W. Claridge

2006-01-01

The genus Hydnoplicata and its type species, H. whitei, were described by Gilkey in 1954. Having discovered that it has amyloid asci and other characters that relate it to the genus Peziza, Trappe later proposed the new combination, Peziza whitei, even though the species is consistently...

Australasian sequestrate fungi 17: The genus Hydnoplicata (Ascomycota, Pezizacae) resurrected

Treesearch

James M. Trappe; Andrew W. Claridge

2006-01-01

The genus Hydnoplicata and its type species, H. whitei, were described by Gilkey in 1954. Having discovered that it has amyloid asci and other characters that relate it to the genus Peziza, Trappe later proposed the new combination, Peziza whiten, even though the species is consistently...

Soil Organic Carbon Fractions Differ in Two Contrasting Tall Fescue Systems

USDA-ARS?s Scientific Manuscript database

The value of tall fescue (Festuca arundinacea Schreb.) for C sequestration in addition to forage production and soil conservation is of current interest. However, studies relating to the impacts of endophyte infected (E+) and endophyte free (E-) tall fescue on soil organic matter fractions are few....

21 CFR 582.6751 - Sodium citrate.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized as...

21 CFR 582.6751 - Sodium citrate.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized as...

21 CFR 582.6751 - Sodium citrate.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized as...

21 CFR 582.6751 - Sodium citrate.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized as...

21 CFR 582.6751 - Sodium citrate.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Sodium citrate. 582.6751 Section 582.6751 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6751 Sodium citrate. (a) Product. Sodium citrate. (b) Conditions of use. This substance is generally recognized as...

Early Executive Function and Mathematics Relations: Correlation Does Not Ensure Concordance.

PubMed

Mazzocco, Michèle M M; Chan, Jenny Yun-Chen; Bock, Allison M

2017-01-01

In this chapter, we address one potentially overlooked component of the relation between executive function (EF) skills and early mathematics, a relation for which there is widespread empirical support. Evidence for this relation has, thus far, been largely correlational. Here we emphasize that because positive correlations do not guarantee concordance among all members of a sample or population, a small but meaningful number of children may either fare well in mathematics despite poor EF skills, or may have strong EF skills despite weak mathematics skills. We propose that attention to different profiles of discordance for EF and mathematics may help identify individualized learning needs for students at risk for mathematics difficulties and disabilities. © 2017 Elsevier Inc. All rights reserved.

A Circular Bioeconomy with Biobased Products from CO2 Sequestration.

PubMed

Venkata Mohan, S; Modestra, J Annie; Amulya, K; Butti, Sai Kishore; Velvizhi, G

2016-06-01

The unprecedented climate change influenced by elevated concentrations of CO2 has compelled the research world to focus on CO2 sequestration. Although existing natural and anthropogenic CO2 sinks have proven valuable, their ability to further assimilate CO2 is now questioned. Thus, we highlight here the importance of biological sequestration methods as alternate and viable routes for mitigating climate change while simultaneously synthesizing value-added products that could sustainably fuel the circular bioeconomy. Four conceptual models for CO2 biosequestration and the synthesis of biobased products, as well as an integrated CO2 biorefinery model, are proposed. Optimizing and implementing this biorefinery model might overcome the limitations of existing sequestration methods and could help realign the carbon balance. Copyright © 2016 Elsevier Ltd. All rights reserved.

Exploring Collective Mathematical Creativity in Elementary School

ERIC Educational Resources Information Center

Levenson, Esther

2011-01-01

This study combines theories related to collective learning and theories related to mathematical creativity to investigate the notion of collective mathematical creativity in elementary school classrooms. Collective learning takes place when mathematical ideas and actions, initially stemming from an individual, are built upon and reworked,…

Dynamic Boolean Mathematics

ERIC Educational Resources Information Center

Bossé, Michael J.; Adu-Gyamfi, Kwaku; Chandler, Kayla; Lynch-Davis, Kathleen

2016-01-01

Dynamic mathematical environments allow users to reify mathematical concepts through multiple representations, transform mathematical relations and organically explore mathematical properties, investigate integrated mathematics, and develop conceptual understanding. Herein, we integrate Boolean algebra, the functionalities of a dynamic…

How sequestration cuts affect primary care physicians and graduate medical education.

PubMed

Chauhan, Bindiya; Coffin, Janis

2013-01-01

On April 1, 2013, sequestration cuts went into effect impacting Medicare physician payments, graduate medical education, and many other healthcare agencies. The cuts range from 2% to 5%, affecting various departments and organizations. There is already a shortage of primary care physicians in general, not including rural or underserved areas, with limited grants for advanced training. The sequestration cuts negatively impact the future of many primary care physicians and hinder the care many Americans will receive over time.

Pedagogical Reform and College WOMEN’S Persistence in Mathematics

NASA Astrophysics Data System (ADS)

Strand, Kerry J. Strand; Mayfield, M. Elizabeth

Significant gender differences persist in the election of mathematics courses and math-related majors in college. Recent research suggests that part of the blame lies with conventional pedagogical approaches and that alternative approaches emphasizing practical applications, collaborative problem solving, and group work make mathematics more understandable and appealing to all students, particularly women. Using questionnaires administered to 355 traditional-age female college students, the authors examined the relationship between alternative teaching strategies in high school mathematics classes and two categories of outcome variables: mathematics-related attitudes and mathematics persistence in college. Multivariate analysis showed that experience with this so-called female-friendly pedagogy is positively related to students’ math-related attitudes and that these attitudes predict math persistence in college. However, the authors’ data also indicate that alternative teaching strategies have no discernible direct effect on students’ choices of mathematics courses or mathrelated

Perspectives for genetic engineering for the phytoremediation of arsenic-contaminated environments: from imagination to reality?

PubMed Central

Zhu, Yong-Guan; Rosen, Barry P

2015-01-01

Phytoremediation to clean up arsenic-contaminated environments has been widely hailed as environmentally friendly and cost effective, and genetic engineering is believed to improve the efficiency and versatility of phytoremediation. Successful genetic engineering requires the thorough understanding of the mechanisms involved in arsenic tolerance and accumulation by natural plant species. Key mechanisms include arsenate reduction, arsenic sequestration in vacuoles of root or shoot, arsenic loading to the xylem, and volatilization through the leaves. Key advances include the identification of arsenic (As) translocation from root to shoot in the As hyperaccumulator, Pteris vittata, and the characterization of related key genes from hyperaccumulator and nonaccumulators. In this paper we have proposed three pathways for genetic engineering: arsenic sequestration in the root, hyperaccumulation of arsenic in aboveground tissues, and phytovolatilization. PMID:19303764

Vegetation turnover and nitrogen feedback drive temperate forest carbon sequestration in response to elevated CO[2]. A multi-model structural analysis

NASA Astrophysics Data System (ADS)

Walker, A. P.; Zaehle, S.; Medlyn, B. E.; De Kauwe, M. G.; Asao, S.; Hickler, T.; Lomas, M. R.; Pak, B. C.; Parton, W. J.; Quegan, S.; Ricciuto, D. M.; Wang, Y.; Warlind, D.; Norby, R. J.

2013-12-01

Predicting forest carbon (C) sequestration requires understanding the processes leading to rates of biomass C accrual (net primary productivity; NPP) and loss (turnover). In temperate forest ecosystems, experiments and models have shown that feedback via progressive nitrogen limitation (PNL) is a key driver of NPP responses to elevated CO[2]. In this analysis we show that while still important, PNL may not be as severe a constraint on NPP as indicated by some studies and that the response of turnover to elevated CO[2] could be as important, especially in the near to medium term. Seven terrestrial ecosystem and biosphere models that couple C and N cycles with varying assumptions and complexity were used to simulate responses over 300 years to a step change in CO[2] to 550 ppmv. Simulations were run for the evergreen needleleaf Duke forest and the deciduous broadleaf Oak Ridge forest FACE experiments. Whether or not a model simulated PNL under elevated CO[2] depended on model structure and the timescale of observation. Avoiding PNL depended on mechanisms that reduced ecosystem N losses. The two key assumptions that reduced N losses were whether plant N uptake was based on plant N demand and whether ecosystem N losses (volatisation and leaching) were dependent on the concentration of N in the soil solution. Assumptions on allocation and turnover resulted in very different responses of turnover to elevated CO[2], which had profound implications for C sequestration. For example, at equilibrium CABLE2.0 predicted an increase in vegetation C sequestration despite decreased NPP, while O-CN predicted much less vegetation C sequestration than would be expected from predicted NPP increases alone. Generally elevated CO[2] favoured a shift in C partitioning towards longer lived wood biomass, which increased vegetation turnover and enhanced C sequestration. Enhanced wood partitioning was overlaid by increases or decreases in self-thinning depended on whether self-thinning was simply a function of forest structure, or structure and NPP. Self-thinning assumptions altered equilibrium C sequestration and were extremely important for the immediate transient response and near-term prediction of C sequestration.

NATIVE PLANTS FOR OPTIMIZING CARBON SEQUESTRATION IN RECLAIMED LANDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

P. UNKEFER; M. EBINGER; ET AL

Carbon emissions and atmospheric concentrations are expected to continue to increase through the next century unless major changes are made in the way carbon is managed. Managing carbon has emerged as a pressing national energy and environmental need that will drive national policies and treaties through the coming decades. Addressing carbon management is now a major priority for DOE and the nation. One way to manage carbon is to use energy more efficiently to reduce our need for major energy and carbon source-fossil fuel combustion. Another way is to increase our use of low-carbon and carbon free fuels and technologies.more » A third way, and the focus of this proposal, is carbon sequestration, in which carbon is captured and stored thereby mitigating carbon emissions. Sequestration of carbon in the terrestrial biosphere has emerged as the principle means by which the US will meet its near-term international and economic requirements for reducing net carbon emissions (DOE Carbon Sequestration: State of the Science. 1999; IGBP 1998). Terrestrial carbon sequestration provides three major advantages. First, terrestrial carbon pools and fluxes are of sufficient magnitude to effectively mitigate national and even global carbon emissions. The terrestrial biosphere stores {approximately}2060 GigaTons of carbon and transfers approximately 120 GigaTons of carbon per year between the atmosphere and the earth's surface, whereas the current global annual emissions are about 6 GigaTons. Second, we can rapidly and readily modify existing management practices to increase carbon sequestration in our extensive forest, range, and croplands. Third, increasing soil carbon is without negative environment consequences and indeed positively impacts land productivity. The terrestrial carbon cycle is dependent on several interrelationships between plants and soils. Because the soil carbon pool ({approximately}1500 Giga Tons) is approximately three times that in terrestrial vegetation ({approximately}560 GigaTons), the principal focus of terrestrial sequestration efforts is to increase soil carbon. But soil carbon ultimately derives from vegetation and therefore must be managed indirectly through aboveground management of vegetation and nutrients. Hence, the response of whole ecosystems must be considered in terrestrial carbon sequestration strategies.« less

Separation and capture of CO2 from large stationary sources and sequestration in geological formations--coalbeds and deep saline aquifers.

PubMed

White, Curt M; Strazisar, Brian R; Granite, Evan J; Hoffman, James S; Pennline, Henry W

2003-06-01

The topic of global warming as a result of increased atmospheric CO2 concentration is arguably the most important environmental issue that the world faces today. It is a global problem that will need to be solved on a global level. The link between anthropogenic emissions of CO2 with increased atmospheric CO2 levels and, in turn, with increased global temperatures has been well established and accepted by the world. International organizations such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Intergovernmental Panel on Climate Change (IPCC) have been formed to address this issue. Three options are being explored to stabilize atmospheric levels of greenhouse gases (GHGs) and global temperatures without severely and negatively impacting standard of living: (1) increasing energy efficiency, (2) switching to less carbon-intensive sources of energy, and (3) carbon sequestration. To be successful, all three options must be used in concert. The third option is the subject of this review. Specifically, this review will cover the capture and geologic sequestration of CO2 generated from large point sources, namely fossil-fuel-fired power gasification plants. Sequestration of CO2 in geological formations is necessary to meet the President's Global Climate Change Initiative target of an 18% reduction in GHG intensity by 2012. Further, the best strategy to stabilize the atmospheric concentration of CO2 results from a multifaceted approach where sequestration of CO2 into geological formations is combined with increased efficiency in electric power generation and utilization, increased conservation, increased use of lower carbon-intensity fuels, and increased use of nuclear energy and renewables. This review covers the separation and capture of CO2 from both flue gas and fuel gas using wet scrubbing technologies, dry regenerable sorbents, membranes, cryogenics, pressure and temperature swing adsorption, and other advanced concepts. Existing commercial CO2 capture facilities at electric power-generating stations based on the use of monoethanolamine are described, as is the Rectisol process used by Dakota Gasification to separate and capture CO2 from a coal gasifier. Two technologies for storage of the captured CO2 are reviewed--sequestration in deep unmineable coalbeds with concomitant recovery of CH4 and sequestration in deep saline aquifers. Key issues for both of these techniques include estimating the potential storage capacity, the storage integrity, and the physical and chemical processes that are initiated by injecting CO2 underground. Recent studies using computer modeling as well as laboratory and field experimentation are presented here. In addition, several projects have been initiated in which CO2 is injected into a deep coal seam or saline aquifer. The current status of several such projects is discussed. Included is a commercial-scale project in which a million tons of CO2 are injected annually into an aquifer under the North Sea in Norway. The review makes the case that this can all be accomplished safely with off-the-shelf technologies. However, substantial research and development must be performed to reduce the cost, decrease the risks, and increase the safety of sequestration technologies. This review also includes discussion of possible problems related to deep injection of CO2. There are safety concerns that need to be addressed because of the possibilities of leakage to the surface and induced seismic activity. These issues are presented along with a case study of a similar incident in the past. It is clear that monitoring and verification of storage will be a crucial part of all geological sequestration practices so that such problems may be avoided. Available techniques include direct measurement of CO2 and CH4 surface soil fluxes, the use of chemical tracers, and underground 4-D seismic monitoring. Ten new hypotheses were formulated to describe what happens when CO2 is pumped into a coal seam. These hypotheses provide significant insight into the fundamental chemical, physical, and thermodynamic phenomena that occur during coal seam sequestration of CO2.

Bile acid sequestrants for cholesterol

MedlinePlus

... ency/patientinstructions/000787.htm Bile acid sequestrants for cholesterol To use the sharing features on this page, ... are medicines that help lower your LDL (bad) cholesterol . Too much cholesterol in your blood can stick ...

The Threshold Hypothesis Applied to Spatial Skill and Mathematics

ERIC Educational Resources Information Center

Freer, Daniel

2017-01-01

This cross-sectional study assessed the relation between spatial skills and mathematics in 854 participants across kindergarten, third grade, and sixth grade. Specifically, the study probed for a threshold for spatial skills when performing mathematics, above which spatial scores and mathematics scores would be significantly less related. This…

Perception determinants in learning mathematics

NASA Astrophysics Data System (ADS)

Mokhtar, Siti Fairus; Ali, Noor Rasidah; Rashid, Nurazlina Abdul

2015-05-01

This article described a statistical study of students' perception in mathematics. The objective of this study is to identify factors related to perception about learning mathematics among non mathematics' student. This study also determined the relationship between of these factors among non mathematics' student. 43 items questionnaires were distributed to one hundred students in UiTM Kedah who enrolled in the Business Mathematics course. These items were measured by using a semantic scale with the following anchors: 1 = strongly disagree to 7 = strongly agree. A factor analysis of respondents were identified into five factors that influencing the students' perception in mathematics. In my study, factors identified were attitude, interest, role of the teacher, role of peers and usefulness of mathematics that may relate to the perception about learning mathematics among non mathematics' student.

The Relation Between Inattentive and Hyperactive/Impulsive Behaviors and Early Mathematics Skills.

PubMed

Sims, Darcey M; Purpura, David J; Lonigan, Christopher J

2016-08-01

Despite strong evidence that inattentive and hyperactive/impulsive behaviors are associated with mathematical difficulties in school-age children, little research has been conducted to examine the link between these constructs before the start of formal education. The purpose of this study was to examine how different manifestations of inattentive and hyperactive/impulsive behaviors, as measured by different assessment tools, are related to early mathematics skills in preschoolers. Eighty-two preschool children completed a measure of early mathematics and the Continuous Performance Test (CPT). Teachers rated children's behaviors using the Conners' Teacher Rating Scale-15 Item. Sixty-five of these children completed mathematics assessments 1 year later. Teacher ratings of inattention were uniquely related to concurrent early mathematics skills, whereas CPT errors were uniquely predictive of early mathematics skills 1 year later. Findings have implications for the understanding and assessment of behavior problems that are associated with early mathematics difficulties. © The Author(s) 2012.

[Computed tomography semiotics of osteonecrosis and sequestration in chronic hematogenic osteomyelitis].

PubMed

D'iachkova, G V; Mitina, Iu L

2007-01-01

Based on the data of computed tomography, radiography and densitometry in 39 patients the authors describe in detail the signs of osteonecrosis and sequestration of different localization and extension.

Special relativity from observer's mathematics point of view

NASA Astrophysics Data System (ADS)

Khots, Boris; Khots, Dmitriy

2015-09-01

When we create mathematical models for quantum theory of light we assume that the mathematical apparatus used in modeling, at least the simplest mathematical apparatus, is infallible. In particular, this relates to the use of "infinitely small" and "infinitely large" quantities in arithmetic and the use of Newton - Cauchy definitions of a limit and derivative in analysis. We believe that is where the main problem lies in contemporary study of nature. We have introduced a new concept of Observer's Mathematics (see www.mathrelativity.com). Observer's Mathematics creates new arithmetic, algebra, geometry, topology, analysis and logic which do not contain the concept of continuum, but locally coincide with the standard fields. We use Einstein special relativity principles and get the analogue of classical Lorentz transformation. This work considers this transformation from Observer's Mathematics point of view.

Proposed roadmap for overcoming legal and financial obstacles to carbon capture and sequestration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacobs, Wendy; Chohen, Leah; Kostakidis-Lianos, Leah

Many existing proposals either lack sufficient concreteness to make carbon capture and geological sequestration (CCGS) operational or fail to focus on a comprehensive, long term framework for its regulation, thus failing to account adequately for the urgency of the issue, the need to develop immediate experience with large scale demonstration projects, or the financial and other incentives required to launch early demonstration projects. We aim to help fill this void by proposing a roadmap to commercial deployment of CCGS in the United States.This roadmap focuses on the legal and financial incentives necessary for rapid demonstration of geological sequestration in themore » absence of national restrictions on CO2 emissions. It weaves together existing federal programs and financing opportunities into a set of recommendations for achieving commercial viability of geological sequestration.« less

Cardiomyopathy Induced by Pulmonary Sequestration in a 50-Year-Old Man

PubMed Central

Chatelain, Shaun; Comp, Robert A.; Grace, R. Randal

2015-01-01

A 50-year-old black man presented at the emergency department with midsternal, nonradiating chest pressure and chronic dyspnea on exertion. Four years before the current admission, he had been diagnosed with nonischemic cardiomyopathy at another facility. After our complete evaluation, we suspected that his symptoms arose from left-to-left shunting in association with pulmonary sequestration, a congenital malformation. Our preliminary diagnosis of secondary dilated cardiomyopathy was confirmed by normalization of the patient's ventricular size and function after lobectomy. To our knowledge, this patient is the oldest on record to present with cardiomyopathy consequent to pulmonary sequestration. His case is highly unusual because of his age and the rapid resolution of his symptoms after lobectomy. We believe that pulmonary sequestration should be included in the differential diagnosis of dilated cardiomyopathy. PMID:25873803

The NatCarb geoportal: Linking distributed data from the Carbon Sequestration Regional Partnerships

USGS Publications Warehouse

Carr, T.R.; Rich, P.M.; Bartley, J.D.

2007-01-01

The Department of Energy (DOE) Carbon Sequestration Regional Partnerships are generating the data for a "carbon atlas" of key geospatial data (carbon sources, potential sinks, etc.) required for rapid implementation of carbon sequestration on a broad scale. The NATional CARBon Sequestration Database and Geographic Information System (NatCarb) provides Web-based, nation-wide data access. Distributed computing solutions link partnerships and other publicly accessible repositories of geological, geophysical, natural resource, infrastructure, and environmental data. Data are maintained and enhanced locally, but assembled and accessed through a single geoportal. NatCarb, as a first attempt at a national carbon cyberinfrastructure (NCCI), assembles the data required to address technical and policy challenges of carbon capture and storage. We present a path forward to design and implement a comprehensive and successful NCCI. ?? 2007 The Haworth Press, Inc. All rights reserved.

Biologically Enhanced Carbon Sequestration: Research Needs and Opportunities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oldenburg, Curtis; Oldenburg, Curtis M.; Torn, Margaret S.

2008-03-21

Fossil fuel combustion, deforestation, and biomass burning are the dominant contributors to increasing atmospheric carbon dioxide (CO{sub 2}) concentrations and global warming. Many approaches to mitigating CO{sub 2} emissions are being pursued, and among the most promising are terrestrial and geologic carbon sequestration. Recent advances in ecology and microbial biology offer promising new possibilities for enhancing terrestrial and geologic carbon sequestration. A workshop was held October 29, 2007, at Lawrence Berkeley National Laboratory (LBNL) on Biologically Enhanced Carbon Sequestration (BECS). The workshop participants (approximately 30 scientists from California, Illinois, Oregon, Montana, and New Mexico) developed a prioritized list of researchmore » needed to make progress in the development of biological enhancements to improve terrestrial and geologic carbon sequestration. The workshop participants also identified a number of areas of supporting science that are critical to making progress in the fundamental research areas. The purpose of this position paper is to summarize and elaborate upon the findings of the workshop. The paper considers terrestrial and geologic carbon sequestration separately. First, we present a summary in outline form of the research roadmaps for terrestrial and geologic BECS. This outline is elaborated upon in the narrative sections that follow. The narrative sections start with the focused research priorities in each area followed by critical supporting science for biological enhancements as prioritized during the workshop. Finally, Table 1 summarizes the potential significance or 'materiality' of advances in these areas for reducing net greenhouse gas emissions.« less

Carbon sequestration and Jerusalem artichoke biomass under nitrogen applications in coastal saline zone in the northern region of Jiangsu, China.

PubMed

Niu, Li; Manxia, Chen; Xiumei, Gao; Xiaohua, Long; Hongbo, Shao; Zhaopu, Liu; Zed, Rengel

2016-10-15

Agriculture is an important source of greenhouse gases, but can also be a significant sink. Nitrogen fertilization is effective in increasing agricultural production and carbon storage. We explored the effects of different rates of nitrogen fertilization on biomass, carbon density, and carbon sequestration in fields under the cultivation of Jerusalem artichoke as well as in soil in a coastal saline zone for two years. Five nitrogen fertilization rates were tested (in guream(-2)): 4 (N1), 8 (N2), 12 (N3), 16 (N4), and 0 (control, CK). The biomass of different organs of Jerusalem artichoke during the growth cycle was significantly higher in N2 than the other treatments. Under different nitrogen treatments, carbon density in organs of Jerusalem artichoke ranged from 336 to 419gCkg(-1). Carbon sequestration in Jerusalem artichoke was higher in treatments with nitrogen fertilization compared to the CK treatment. The highest carbon sequestration was found in the N2 treatment. Soil carbon content was higher in the 0-10cm than 10-20cm layer, with nitrogen fertilization increasing carbon content in both soil layers. The highest soil carbon sequestration was measured in the N2 treatment. Carbon sequestration in both soil and Jerusalem artichoke residue was increased by nitrogen fertilization depending on the rates in the coastal saline zone studied. Copyright © 2016 Elsevier B.V. All rights reserved.

Using Mathematics, Mathematical Applications, Mathematical Modelling, and Mathematical Literacy: A Theoretical Study

ERIC Educational Resources Information Center

Mumcu, Hayal Yavuz

2016-01-01

The purpose of this theoretical study is to explore the relationships between the concepts of using mathematics in the daily life, mathematical applications, mathematical modelling, and mathematical literacy. As these concepts are generally taken as independent concepts in the related literature, they are confused with each other and it becomes…

Relations of different types of numerical magnitude representations to each other and to mathematics achievement.

PubMed

Fazio, Lisa K; Bailey, Drew H; Thompson, Clarissa A; Siegler, Robert S

2014-07-01

We examined relations between symbolic and non-symbolic numerical magnitude representations, between whole number and fraction representations, and between these representations and overall mathematics achievement in fifth graders. Fraction and whole number symbolic and non-symbolic numerical magnitude understandings were measured using both magnitude comparison and number line estimation tasks. After controlling for non-mathematical cognitive proficiency, both symbolic and non-symbolic numerical magnitude understandings were uniquely related to mathematics achievement, but the relation was much stronger for symbolic numbers. A meta-analysis of 19 published studies indicated that relations between non-symbolic numerical magnitude knowledge and mathematics achievement are present but tend to be weak, especially beyond 6 years of age. Copyright © 2014 Elsevier Inc. All rights reserved.

A Meta-Analysis of Mathematics and Working Memory: Moderating Effects of Working Memory Domain, Type of Mathematics Skill, and Sample Characteristics

ERIC Educational Resources Information Center

Peng, Peng; Namkung, Jessica; Barnes, Marcia; Sun, Congying

2016-01-01

The purpose of this meta-analysis was to determine the relation between mathematics and working memory (WM) and to identify possible moderators of this relation including domains of WM, types of mathematics skills, and sample type. A meta-analysis of 110 studies with 829 effect sizes found a significant medium correlation of mathematics and WM, r…

The relation between children’s constructive play activities, spatial ability, and mathematical word problem-solving performance: a mediation analysis in sixth-grade students

PubMed Central

Oostermeijer, Meike; Boonen, Anton J. H.; Jolles, Jelle

2014-01-01

The scientific literature shows that constructive play activities are positively related to children’s spatial ability. Likewise, a close positive relation is found between spatial ability and mathematical word problem-solving performances. The relation between children’s constructive play and their performance on mathematical word problems is, however, not reported yet. The aim of the present study was to investigate whether spatial ability acted as a mediator in the relation between constructive play and mathematical word problem-solving performance in 128 sixth-grade elementary school children. This mediating role of spatial ability was tested by utilizing the current mediation approaches suggested by Preacher and Hayes (2008). Results showed that 38.16% of the variance in mathematical word problem-solving performance is explained by children’s constructive play activities and spatial ability. More specifically, spatial ability acted as a partial mediator, explaining 31.58% of the relation between constructive play and mathematical word problem-solving performance. PMID:25101038

Project-Based Learning and Design-Focused Projects to Motivate Secondary Mathematics Students

ERIC Educational Resources Information Center

Remijan, Kelly W.

2017-01-01

This article illustrates how mathematics teachers can develop design-focused projects, related to project-based learning, to motivate secondary mathematics students. With first-hand experience as a secondary mathematics teacher, I provide a series of steps related to the engineering design process, which are helpful to teachers in developing…

The Transition from School to University in Mathematics: Which Influence Do School-Related Variables Have?

ERIC Educational Resources Information Center

Rach, Stefanie; Heinze, Aiso

2017-01-01

Particularly in mathematics, the transition from school to university often appears to be a substantial hurdle in the individual learning biography. Differences between the characters of school mathematics and scientific university mathematics as well as different demands related to the learning cultures in both institutions are discussed as…

Mathematics-Related Anxiety and Attitudes: Examining the Impact among Latina Preservice Teachers

ERIC Educational Resources Information Center

Gautreau, Cynthia; Brye, Michelle VanderVeldt; Lunceford, Christina

2016-01-01

The purpose of this study was to investigate mathematics-related anxiety and attitudes among Latina preservice teachers. Three sections from the Inventory of Mathematics Attitudes, Experience, and Self Awareness were administered to preservice teachers enrolled in a curriculum and instruction mathematics course during the 1st semester of a…

Effect of heterogeneousatmospheric CO2 on simulated global carbon budget

USGS Publications Warehouse

Zhang, Zhen; Jiang, Hong; Liu, Jinxun; Ju, Weimin; Zhang, Xiuying

2013-01-01

The effects of rising atmospheric carbon dioxide (CO2) on terrestrial carbon (C) sequestration have been a key focus in global change studies. As anthropological CO2 emissions substantially increase, the spatial variability of atmospheric CO2 should be considered to reduce the potential bias on C source and sink estimations. In this study, the global spatial–temporal patterns of near surface CO2 concentrations for the period 2003-2009 were established using the SCIAMACHY satellite observations and the GLOBALVIEW-CO2 field observations. With this CO2 data and the Integrated Biosphere Simulator (IBIS), our estimation of the global mean annual NPP and NEP was 0.5% and 7% respectively which differs from the traditional C sequestration assessments. The Amazon, Southeast Asia, and Tropical Africa showed higher C sequestration than the traditional assessment, and the rest of the areas around the world showed slightly lower C sequestration than the traditional assessment. We find that the variability of NEP is less intense under heterogeneous CO2 pattern on a global scale. Further studies of the cause of CO2 variation and the interactions between natural and anthropogenic processes of C sequestration are needed.

Calcium silicates synthesised from industrial residues with the ability for CO2 sequestration.

PubMed

Morales-Flórez, Victor; Santos, Alberto; López, Antonio; Moriña, Isabel; Esquivias, Luis

2014-12-01

This work explored several synthesis routes to obtain calcium silicates from different calcium-rich and silica-rich industrial residues. Larnite, wollastonite and calcium silicate chloride were successfully synthesised with moderate heat treatments below standard temperatures. These procedures help to not only conserve natural resources, but also to reduce the energy requirements and CO2 emissions. In addition, these silicates have been successfully tested as carbon dioxide sequesters, to enhance the viability of CO2 mineral sequestration technologies using calcium-rich industrial by-products as sequestration agents. Two different carbon sequestration experiments were performed under ambient conditions. Static experiments revealed carbonation efficiencies close to 100% and real-time resolved experiments characterised the dynamic behaviour and ability of these samples to reduce the CO2 concentration within a mixture of gases. The CO2 concentration was reduced up to 70%, with a carbon fixation dynamic ratio of 3.2 mg CO2 per g of sequestration agent and minute. Our results confirm the suitability of the proposed synthesis routes to synthesise different calcium silicates recycling industrial residues, being therefore energetically more efficient and environmentally friendly procedures for the cement industry. © The Author(s) 2014.

21 CFR 582.6033 - Citric acid.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Citric acid. 582.6033 Section 582.6033 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6033 Citric acid. (a) Product. Citric acid. 2 For the purpose of this subpart, no attempt has been made to...

21 CFR 582.6033 - Citric acid.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Citric acid. 582.6033 Section 582.6033 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6033 Citric acid. (a) Product. Citric acid. 2 For the purpose of this subpart, no attempt has been made to...

21 CFR 582.6033 - Citric acid.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Citric acid. 582.6033 Section 582.6033 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6033 Citric acid. (a) Product. Citric acid. 2 For the purpose of this subpart, no attempt has been made to...

21 CFR 582.6033 - Citric acid.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Citric acid. 582.6033 Section 582.6033 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6033 Citric acid. (a) Product. Citric acid. 2 For the purpose of this subpart, no attempt has been made to...

21 CFR 582.6033 - Citric acid.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Citric acid. 582.6033 Section 582.6033 Food and..., FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Sequestrants 2 § 582.6033 Citric acid. (a) Product. Citric acid. 2 For the purpose of this subpart, no attempt has been made to...

The enigmatic truffle Fevansia aurantiaca is an ectomycorrhizal member of the Albatrellus lineage

Treesearch

Matthew E. Smith; Karlee J. Schell; Michael Castellano; Matthew J. Trappe; James M. Trappe

2013-01-01

Fevansia aurantiaca is an orange-colored truffle that has been collected infrequently in the Pacific Northwest of the USA. This sequestrate, hypogeous fungus was originally thought to be related to the genera Rhizopogon or Alpova in the Boletales, but the large, inflated cells in the trama and the very pale...

ESTIMATING THE TERRESTIAL CARBON POOLS OF THE FORMER SOVIET UNION, CONTERMINOUS U.S., AND BRAZIL

EPA Science Inventory

Terrestrial-carbon (C) pool sizes are of interest in relation to quantifying current sources and sinks of C, and evaluating the possibilities for future C sequestration or release by the biosphere. In this study, the C pools in the terrestrial ecosystems of the former Soviet Unio...

Carbon capture and sequestration (CCS)

DOT National Transportation Integrated Search

2009-06-19

Carbon capture and sequestration (or storage)known as CCShas attracted interest as a : measure for mitigating global climate change because large amounts of carbon dioxide (CO2) : emitted from fossil fuel use in the United States are potentiall...

Exploring individual differences in children's mathematical skills: a correlational and dimensional approach.

PubMed

Sigmundsson, H; Polman, R C J; Lorås, H

2013-08-01

Individual differences in mathematical skills are typically explained by an innate capability to solve mathematical tasks. At the behavioural level this implies a consistent level of mathematical achievement that can be captured by strong relationships between tasks, as well as by a single statistical dimension that underlies performance on all mathematical tasks. To investigate this general assumption, the present study explored interrelations and dimensions of mathematical skills. For this purpose, 68 ten-year-old children from two schools were tested using nine mathematics tasks from the Basic Knowledge in Mathematics Test. Relatively low-to-moderate correlations between the mathematics tasks indicated most tasks shared less than 25% of their variance. There were four principal components, accounting for 70% of the variance in mathematical skill across tasks and participants. The high specificity in mathematical skills was discussed in relation to the principle of task specificity of learning.

Experimental burial inhibits methanogenesis and anaerobic decomposition in water-saturated peats.

PubMed

Blodau, Christian; Siems, Melanie; Beer, Julia

2011-12-01

A mechanistic understanding of carbon (C) sequestration and methane (CH(4)) production is of great interest due to the importance of these processes for the global C budget. Here we demonstrate experimentally, by means of column experiments, that burial of water saturated, anoxic bog peat leads to inactivation of anaerobic respiration and methanogenesis. This effect can be related to the slowness of diffusive transport of solutes and evolving energetic constraints on anaerobic respiration. Burial lowered decomposition constants in homogenized peat sand mixtures from about 10(-5) to 10(-7) yr(-1), which is considerably slower than previously assumed, and methanogenesis slowed down in a similar manner. The latter effect could be related to acetoclastic methanogenesis approaching a minimum energy quantum of -25 kJ mol(-1) (CH(4)). Given the robustness of hydraulic properties that locate the oxic-anoxic boundary near the peatland surface and constrain solute transport deeper into the peat, this effect has likely been critical for building the peatland C store and will continue supporting long-term C sequestration in northern peatlands even under moderately changing climatic conditions.

Detailing Relational Interactions in Urban Elementary Mathematics Classrooms

ERIC Educational Resources Information Center

Battey, Dan; Neal, Rebecca A.

2018-01-01

The lack of quality of instruction in urban mathematics classrooms in the United States has received much attention in the scholarly literature. Other classroom mechanisms such as relational interactions, however, have not received much attention of mathematics education researchers. Relational interactions go above and beyond content instruction…

Carbon Capture and Storage, 2008

ScienceCinema

None

2017-12-09

The U.S. Department of Energy is researching the safe implementation of a technology called carbon sequestration, also known as carbon capture and storage, or CCS. Based on an oilfield practice, this approach stores carbon dioxide, or CO2 generated from human activities for millennia as a means to mitigate global climate change. In 2003, the Department of Energys National Energy Technology Laboratory formed seven Regional Carbon Sequestration Partnerships to assess geologic formations suitable for storage and to determine the best approaches to implement carbon sequestration in each region. This video describes the work of these partnerships.

A United States marine presenting with hemoptysis after push-ups.

PubMed

Thurber, John S; Unger, Jason A; DeVries, William C

2014-04-01

We present an unusual case of right lower lobe intralobar pulmonary sequestration in a previously healthy and physical active 27-year-old U.S. Marine, who presented with new onset hemoptysis after doing push-ups. Diagnosis was obtained by chest X-ray and contrast computed tomography scan. Preoperatively the patient underwent fluoroscopy-guided embolization of the aberrant systemic artery supplying the sequestration. The segmental resection of the sequestration was then successfully performed through a muscle-sparing thoracotomy. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

Mathematical background and attitudes toward statistics in a sample of Spanish college students.

PubMed

Carmona, José; Martínez, Rafael J; Sánchez, Manuel

2005-08-01

To examine the relation of mathematical background and initial attitudes toward statistics of Spanish college students in social sciences the Survey of Attitudes Toward Statistics was given to 827 students. Multivariate analyses tested the effects of two indicators of mathematical background (amount of exposure and achievement in previous courses) on the four subscales. Analysis suggested grades in previous courses are more related to initial attitudes toward statistics than the number of mathematics courses taken. Mathematical background was related with students' affective responses to statistics but not with their valuing of statistics. Implications of possible research are discussed.

Relationship between academic motivation and mathematics achievement among Indian adolescents in Canada and India.

PubMed

Areepattamannil, Shaljan

2014-01-01

This study examined the relationships between academic motivation-intrinsic motivation, extrinsic motivation, amotivation-and mathematics achievement among 363 Indian adolescents in India and 355 Indian immigrant adolescents in Canada. Results of hierarchical multiple regression analyses showed that intrinsic motivation, extrinsic motivation, and amotivation were not statistically significantly related to mathematics achievement among Indian adolescents in India. In contrast, both intrinsic motivation and extrinsic motivation were statistically significantly related to mathematics achievement among Indian immigrant adolescents in Canada. While intrinsic motivation was a statistically significant positive predictor of mathematics achievement among Indian immigrant adolescents in Canada, extrinsic motivation was a statistically significant negative predictor of mathematics achievement among Indian immigrant adolescents in Canada. Amotivation was not statistically significantly related to mathematics achievement among Indian immigrant adolescents in Canada. Implications of the findings for pedagogy and practice are discussed.

Quantifying and Mapping the Supply of and Demand for Carbon Storage and Sequestration Service from Urban Trees

PubMed Central

Zhao, Chang; Sander, Heather A.

2015-01-01

Studies that assess the distribution of benefits provided by ecosystem services across urban areas are increasingly common. Nevertheless, current knowledge of both the supply and demand sides of ecosystem services remains limited, leaving a gap in our understanding of balance between ecosystem service supply and demand that restricts our ability to assess and manage these services. The present study seeks to fill this gap by developing and applying an integrated approach to quantifying the supply and demand of a key ecosystem service, carbon storage and sequestration, at the local level. This approach follows three basic steps: (1) quantifying and mapping service supply based upon Light Detection and Ranging (LiDAR) processing and allometric models, (2) quantifying and mapping demand for carbon sequestration using an indicator based on local anthropogenic CO2 emissions, and (3) mapping a supply-to-demand ratio. We illustrate this approach using a portion of the Twin Cities Metropolitan Area of Minnesota, USA. Our results indicate that 1735.69 million kg carbon are stored by urban trees in our study area. Annually, 33.43 million kg carbon are sequestered by trees, whereas 3087.60 million kg carbon are emitted by human sources. Thus, carbon sequestration service provided by urban trees in the study location play a minor role in combating climate change, offsetting approximately 1% of local anthropogenic carbon emissions per year, although avoided emissions via storage in trees are substantial. Our supply-to-demand ratio map provides insight into the balance between carbon sequestration supply in urban trees and demand for such sequestration at the local level, pinpointing critical locations where higher levels of supply and demand exist. Such a ratio map could help planners and policy makers to assess and manage the supply of and demand for carbon sequestration. PMID:26317530

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brian McPherson

The Southwest Partnership on Carbon Sequestration completed its Phase I program in December 2005. The main objective of the Southwest Partnership Phase I project was to evaluate and demonstrate the means for achieving an 18% reduction in carbon intensity by 2012. Many other goals were accomplished on the way to this objective, including (1) analysis of CO{sub 2} storage options in the region, including characterization of storage capacities and transportation options, (2) analysis and summary of CO{sub 2} sources, (3) analysis and summary of CO{sub 2} separation and capture technologies employed in the region, (4) evaluation and ranking of themore » most appropriate sequestration technologies for capture and storage of CO{sub 2} in the Southwest Region, (5) dissemination of existing regulatory/permitting requirements, and (6) assessing and initiating public knowledge and acceptance of possible sequestration approaches. Results of the Southwest Partnership's Phase I evaluation suggested that the most convenient and practical ''first opportunities'' for sequestration would lie along existing CO{sub 2} pipelines in the region. Action plans for six Phase II validation tests in the region were developed, with a portfolio that includes four geologic pilot tests distributed among Utah, New Mexico, and Texas. The Partnership will also conduct a regional terrestrial sequestration pilot program focusing on improved terrestrial MMV methods and reporting approaches specific for the Southwest region. The sixth and final validation test consists of a local-scale terrestrial pilot involving restoration of riparian lands for sequestration purposes. The validation test will use desalinated waters produced from one of the geologic pilot tests. The Southwest Regional Partnership comprises a large, diverse group of expert organizations and individuals specializing in carbon sequestration science and engineering, as well as public policy and outreach. These partners include 21 state government agencies and universities, five major electric utility companies, seven oil, gas and coal companies, three federal agencies, the Navajo Nation, several NGOs, and the Western Governors Association. This group is continuing its work in the Phase II Validation Program, slated to conclude in 2009.« less

Towards Providing Solutions to the Air Quality Crisis in the Mexico City Metropolitan Area: Carbon Sequestration by Succulent Species in Green Roofs

PubMed Central

Collazo-Ortega, Margarita; Rosas, Ulises; Reyes-Santiago, Jerónimo

2017-01-01

INTRODUCTION: In the first months of 2016, the Mexico City Metropolitan Area experienced the worst air pollution crisis in the last decade, prompting drastic short-term solutions by the Mexico City Government and neighboring States. In order to help further the search for long-term sustainable solutions, we felt obliged to immediately release the results of our research regarding the monitoring of carbon sequestration by green roofs. Large-scale naturation, such as the implementation of green roofs, provides a way to partially mitigate the increased carbon dioxide output in urban areas. METHODS: Here, we quantified the carbon sequestration capabilities of two ornamental succulent plant species, Sedum dendroideum and Sedum rubrotinctum, which require low maintenance, and little or no irrigation. To obtain a detailed picture of these plants’ carbon sequestration capabilities, we measured carbon uptake on the Sedum plants by quantifying carbon dioxide exchange and fixation as organic acids, during the day and across the year, on a green roof located in Southern Mexico City. RESULTS: The species displayed their typical CAM photosynthetic metabolism. Moreover, our quantification allowed us to conservatively estimate that a newly planted green roof of Sedum sequesters approximately 180,000,000 ppm of carbon dioxide per year in a green roof of 100 square meters in the short term. DISCUSSION: The patterns of CAM and carbon dioxide sequestration were highly robust to the fluctuations of temperature and precipitation between seasons, and therefore we speculate that carbon sequestration would be comparable in any given year of a newly planted green roof. Older green roof would require regular trimming to mantain their carbon sink properties, but their carbon sequestration capabilities remain to be quantified. Nevertheless, we propose that Sedum green roofs can be part of the long-term solutions to mitigate the air pollution crisis in the Mexico City Metropolitan area, and other “megacities” with marked seasonal drought. PMID:28480127

Towards Providing Solutions to the Air Quality Crisis in the Mexico City Metropolitan Area: Carbon Sequestration by Succulent Species in Green Roofs.

PubMed

Collazo-Ortega, Margarita; Rosas, Ulises; Reyes-Santiago, Jerónimo

2017-03-31

In the first months of 2016, the Mexico City Metropolitan Area experienced the worst air pollution crisis in the last decade, prompting drastic short-term solutions by the Mexico City Government and neighboring States. In order to help further the search for long-term sustainable solutions, we felt obliged to immediately release the results of our research regarding the monitoring of carbon sequestration by green roofs. Large-scale naturation, such as the implementation of green roofs, provides a way to partially mitigate the increased carbon dioxide output in urban areas. Here, we quantified the carbon sequestration capabilities of two ornamental succulent plant species, Sedum dendroideum and Sedum rubrotinctum, which require low maintenance, and little or no irrigation. To obtain a detailed picture of these plants' carbon sequestration capabilities, we measured carbon uptake on the Sedum plants by quantifying carbon dioxide exchange and fixation as organic acids, during the day and across the year, on a green roof located in Southern Mexico City. The species displayed their typical CAM photosynthetic metabolism. Moreover, our quantification allowed us to conservatively estimate that a newly planted green roof of Sedum sequesters approximately 180,000,000 ppm of carbon dioxide per year in a green roof of 100 square meters in the short term. The patterns of CAM and carbon dioxide sequestration were highly robust to the fluctuations of temperature and precipitation between seasons, and therefore we speculate that carbon sequestration would be comparable in any given year of a newly planted green roof. Older green roof would require regular trimming to mantain their carbon sink properties, but their carbon sequestration capabilities remain to be quantified. Nevertheless, we propose that Sedum green roofs can be part of the long-term solutions to mitigate the air pollution crisis in the Mexico City Metropolitan area, and other "megacities" with marked seasonal drought.

Southwestern Regional Partnership For Carbon Sequestration (Phase 2) Pump Canyon CO2- ECBM/Sequestration Demonstration, San Juan Basin, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Advanced Resources International

2010-01-31

Within the Southwest Regional Partnership on Carbon Sequestration (SWP), three demonstrations of geologic CO{sub 2} sequestration are being performed -- one in an oilfield (the SACROC Unit in the Permian basin of west Texas), one in a deep, unmineable coalbed (the Pump Canyon site in the San Juan basin of northern New Mexico), and one in a deep, saline reservoir (underlying the Aneth oilfield in the Paradox basin of southeast Utah). The Pump Canyon CO{sub 2}-enhanced coalbed methane (CO{sub 2}/ECBM) sequestration demonstration project plans to demonstrate the effectiveness of CO{sub 2} sequestration in deep, unmineable coal seams via a small-scalemore » geologic sequestration project. The site is located in San Juan County, northern New Mexico, just within the limits of the high-permeability fairway of prolific coalbed methane production. The study area for the SWP project consists of 31 coalbed methane production wells located in a nine section area. CO{sub 2} was injected continuously for a year and different monitoring, verification and accounting (MVA) techniques were implemented to track the CO{sub 2} movement inside and outside the reservoir. Some of the MVA methods include continuous measurement of injection volumes, pressures and temperatures within the injection well, coalbed methane production rates, pressures and gas compositions collected at the offset production wells, and tracers in the injected CO{sub 2}. In addition, time-lapse vertical seismic profiling (VSP), surface tiltmeter arrays, a series of shallow monitoring wells with a regular fluid sampling program, surface measurements of soil composition, CO{sub 2} fluxes, and tracers were used to help in tracking the injected CO{sub 2}. Finally, a detailed reservoir model was constructed to help reproduce and understand the behavior of the reservoir under production and injection operation. This report summarizes the different phases of the project, from permitting through site closure, and gives the results of the different MVA techniques.« less

Direct gas-solid carbonation kinetics of steel slag and the contribution to in situ sequestration of flue gas CO(2) in steel-making plants.

PubMed

Tian, Sicong; Jiang, Jianguo; Chen, Xuejing; Yan, Feng; Li, Kaimin

2013-12-01

Direct gas-solid carbonation of steel slag under various operational conditions was investigated to determine the sequestration of the flue gas CO2 . X-ray diffraction analysis of steel slag revealed the existence of portlandite, which provided a maximum theoretical CO2 sequestration potential of 159.4 kg CO 2 tslag (-1) as calculated by the reference intensity ratio method. The carbonation reaction occurred through a fast kinetically controlled stage with an activation energy of 21.29 kJ mol(-1) , followed by 10(3) orders of magnitude slower diffusion-controlled stage with an activation energy of 49.54 kJ mol(-1) , which could be represented by a first-order reaction kinetic equation and the Ginstling equation, respectively. Temperature, CO2 concentration, and the presence of SO2 impacted on the carbonation conversion of steel slag through their direct and definite influence on the rate constants. Temperature was the most important factor influencing the direct gas-solid carbonation of steel slag in terms of both the carbonation conversion and reaction rate. CO2 concentration had a definite influence on the carbonation rate during the kinetically controlled stage, and the presence of SO2 at typical flue gas concentrations enhanced the direct gas-solid carbonation of steel slag. Carbonation conversions between 49.5 % and 55.5 % were achieved in a typical flue gas at 600 °C, with the maximum CO2 sequestration amount generating 88.5 kg CO 2 tslag (-1) . Direct gas-solid carbonation of steel slag showed a rapid CO2 sequestration rate, high CO2 sequestration amounts, low raw-material costs, and a large potential for waste heat utilization, which is promising for in situ carbon capture and sequestration in the steel industry. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biorefineries of carbon dioxide: From carbon capture and storage (CCS) to bioenergies production.

PubMed

Cheah, Wai Yan; Ling, Tau Chuan; Juan, Joon Ching; Lee, Duu-Jong; Chang, Jo-Shu; Show, Pau Loke

2016-09-01

Greenhouse gas emissions have several adverse environmental effects, like pollution and climate change. Currently applied carbon capture and storage (CCS) methods are not cost effective and have not been proven safe for long term sequestration. Another attractive approach is CO2 valorization, whereby CO2 can be captured in the form of biomass via photosynthesis and is subsequently converted into various form of bioenergy. This article summarizes the current carbon sequestration and utilization technologies, while emphasizing the value of bioconversion of CO2. In particular, CO2 sequestration by terrestrial plants, microalgae and other microorganisms are discussed. Prospects and challenges for CO2 conversion are addressed. The aim of this review is to provide comprehensive knowledge and updated information on the current advances in biological CO2 sequestration and valorization, which are essential if this approach is to achieve environmental sustainability and economic feasibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

Robust CO2 Injection: Application of Bayesian-Information-Gap Decision Theory

NASA Astrophysics Data System (ADS)

Grasinger, M.; O'Malley, D.; Vesselinov, V. V.; Karra, S.

2015-12-01

Carbon capture and sequestration has the potential to reduce greenhouse gasemissions. However, care must be taken when choosing a site for CO2 seques-tration to ensure that the CO2 remains sequestered for many years, and thatthe environment is not harmed in any way. Making a rational decision be-tween potential sites for sequestration is not without its challenges because, asin the case of many environmental and subsurface problems, there is a lot ofuncertainty that exists. A method for making decisions under various typesand severities of uncertainty, Bayesian-Information-Gap Decision Theory (BIGDT), is presented. BIG DT was coupled with a numerical model for CO2 wellinjection and the resulting framework was then applied to a problem of selectingbetween two potential sites for CO2 sequestration. The results of the analysisare presented, followed by a discussion of the decision process.

An Alternative Mechanism for Accelerated Carbon Sequestration in Concrete

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haselbach, Liv M.; Thomle, Jonathan N.

The increased rate of carbon dioxide sequestration (carbonation) is desired in many primary and secondary life applications of concrete in order to make the life cycle of concrete structures more carbon neutral. Most carbonation rate studies have focused on concrete exposed to air under various conditions. An alternative mechanism for accelerated carbon sequestration in concrete was investigated in this research based on the pH change of waters in contact with pervious concrete which have been submerged in carbonate laden waters. The results indicate that the concrete exposed to high levels of carbonate species in water may carbonate faster than whenmore » exposed to ambient air, and that the rate is higher with higher concentrations. Validation of increased carbon dioxide sequestration was also performed via thermogravimetric analysis (TGA). It is theorized that the proposed alternative mechanism reduces a limiting rate effect of carbon dioxide dissolution in water in the micro pores of the concrete.« less

A Comparison of Red Cell Rejuvenation versus Mechanical Washing for the Prevention of Transfusion-associated Organ Injury in Swine.

PubMed

Woźniak, Marcin J; Qureshi, Saqib; Sullo, Nikol; Dott, William; Cardigan, Rebecca; Wiltshire, Michael; Nath, Mintu; Patel, Nishith N; Kumar, Tracy; Goodall, Alison H; Murphy, Gavin J

2018-02-01

We evaluated the effects of two interventions that modify the red cell storage lesion on kidney and lung injury in experimental models of transfusion. White-landrace pigs (n = 32) were allocated to receive sham transfusion (crystalloid), 14-day stored allogeneic red cells, 14-day red cells washed using the red cells washing/salvage system (CATS; Fresenius, Germany), or 14-day red cells rejuvenated using the inosine solution (Rejuvesol solution; Zimmer Biomet, USA) and washed using the CATS device. Functional, biochemical, and histologic markers of organ injury were assessed for up to 24 h posttransfusion. Transfusion of 14 day red cells resulted in lung injury (lung injury score vs. sham, mean difference -0.3 (95% CI, -0.6 to -0.1; P = 0.02), pulmonary endothelial dysfunction, and tissue leukocyte sequestration. Mechanical washing reduced red cell-derived microvesicles but increased cell-free hemoglobin in 14-day red cell units. Transfusion of washed red cells reduced leukocyte sequestration but did not reduce the lung injury score (mean difference -0.2; 95% CI, -0.5 to 0.1; P = 0.19) relative to 14-day cells. Transfusion of washed red cells also increased endothelial activation and kidney injury. Rejuvenation restored adenosine triphosphate to that of fresh red cells and reduced microvesicle concentrations without increasing cell-free hemoglobin release. Transfusion of rejuvenated red cells reduced plasma cell-free hemoglobin, leukocyte sequestration, and endothelial dysfunction in recipients and reduced lung and kidney injury relative to 14-day or washed 14-day cells. Reversal of the red cell storage lesion by rejuvenation reduces transfusion-associated organ injury in swine.

Effect of chemical environment and rock composition on fracture mechanics properties of reservoir lithologies in context of CO2 sequestration

NASA Astrophysics Data System (ADS)

Major, J. R.; Eichhubl, P.; Callahan, O. A.

2015-12-01

The coupled chemical and mechanical response of reservoir and seal rocks to injection of CO2 have major implications on the short and long term security of sequestered carbon. Many current numerical models evaluating behavior of reservoirs and seals during and after CO2 injection in the subsurface consider chemistry and mechanics separately and use only simple mechanical stability criteria while ignoring time-dependent failure parameters. CO2 injection irreversibly alters the subsurface chemical environment which can then affect geomechanical properties on a range of time scales by altering rock mineralogy and cements through dissolution, remobilization, and precipitation. It has also been documented that geomechanical parameters such as fracture toughness (KIC) and subcritical index (SCI) are sensitive to chemical environment. Double torsion fracture mechanics testing of reservoir lithologies under controlled environmental conditions relevant to CO2 sequestration show that chemical environment can measurably affect KIC and SCI. This coupled chemical-mechanical behavior is also influenced by rock composition, grains, amount and types of cement, and fabric. Fracture mechanics testing of the Aztec Sandstone, a largely silica-cemented, subarkose sandstone demonstrate it is less sensitive to chemical environment than Entrada Sandstone, a silty, clay-rich sandstone. The presence of de-ionized water lowers KIC by approximately 20% and SCI 30% in the Aztec Sandstone relative to tests performed in air, whereas the Entrada Sandstone shows reductions on the order of 70% and 90%, respectively. These results indicate that rock composition influences the chemical-mechanical response to deformation, and that the relative chemical reactivity of target reservoirs should be recognized in context of CO2 sequestration. In general, inert grains and cements such as quartz will be less sensitive to the changing subsurface environment than carbonates and clays.

An Organochronology and Deep History of a North Carolina Tidal Marsh

NASA Astrophysics Data System (ADS)

Morris, J. T.; Kemp, A.; Horton, B.

2016-12-01

Tidal marshes have survived for millennia in a dynamic equilibrium with sea level. A record of their history can be found in the sediments underlying modern marshes. Since the industrial revolution the rate of relative sea-level rise has been increasing and the equilibrium is changing. To reconstruct the history of these marshes we analyzed a 1000 year record of soil organic matter content (SOM) from Tump Point, Cedar Island, North Carolina. SOM concentration is a function of the standing biomass at the time of its creation, its subsequent preservation, and annual input of inorganic matter. SOM and inorganic concentration determine the soil bulk density and volume. The standing biomass, sediment organic matter input, and consequent carbon sequestration are functions of hydroperiod or, by proxy, the paleo-marsh elevation (PME) below mean high water. The annual input of inorganic matter is determined by the depth, duration, and frequency of flooding, concentration of total suspended solids (TSS), and settling velocity. Using an inverse modeling technique we were able to solve the Marsh Equilibrium Model (MEM) for PME and relative sea level that would have resulted in the observed SOM chronologies. The TSS was inferred from the accretion rates derived from dated core sections. Consistent with foraminifera-derived relative sea-level reconstructions, the MEM-derived rate of SLR doubled after 1700 CE compared with the previous 900 years, and the PME has declined and is approaching the lower limit of the vegetation. We estimate that C-sequestration prior to 1260 varied between 15 and 40 (average 30) g C m-2 y-1, but has since declined to a range of 5 to 33 (average 16) g C m-2 y-1. The decline in carbon sequestration can be attributed to the acceleration in rate of sea-level rise and is a trend that probably will characterize most tidal wetlands in the future.

The Impact of Afforestation on Soil Organic Carbon Sequestration on the Qinghai Plateau, China

PubMed Central

Shi, Sheng-wei; Han, Peng-fei; Zhang, Ping; Ding, Fan; Ma, Cheng-lin

2015-01-01

Afforestation, the conversion of non-forested land into forest, is widespread in China. However, the dynamics of soil organic carbon (SOC) after afforestation are not well understood, especially in plateau climate zones. For a total of 48 shrub- and/or tree-dominated afforestation sites on the Qinghai Plateau, Northwestern China, post-afforestation changes in SOC, total nitrogen (TN), the carbon-to-nitrogen ratio (C/N) and soil bulk density (BD) were investigated to a soil depth of 60 cm using the paired-plots method. SOC and TN accumulated at rates of 138.2 g C m-2 yr-1 and 4.6 g N m-2 yr-1, respectively, in shrub-dominated afforestation sites and at rates of 113.3 g C m-2 yr--1 and 6.7 g N m-2yr-1, respectively, in tree-dominated afforestation sites. Soil BD was slightly reduced in all layers in the shrub-dominated afforestation plots, and significantly reduced in soil layers from 0–40cm in the tree-dominated afforestation plots. The C/N ratio was higher in afforested sites relative to the reference sites. SOC accumulation was closely related to TN accumulation following afforestation, and the inclusion of N-fixing species in tree-dominated afforestation sites additionally increased the soil accumulation capacity for SOC (p < 0.05). Multiple regression models including the age of an afforestation plot and total number of plant species explained 75% of the variation in relative SOC content change at depth of 0–20 cm, in tree-dominated afforestation sites. We conclude that afforestation on the Qinghai Plateau is associated with great capability of SOC and TN sequestration. This study improves our understanding of the mechanisms underlying SOC and TN accumulation in a plateau climate, and provides evidence on the C sequestration potentials associated with forestry projects in China. PMID:25706724

The impact of afforestation on soil organic carbon sequestration on the Qinghai Plateau, China.

PubMed

Shi, Sheng-wei; Han, Peng-fei; Zhang, Ping; Ding, Fan; Ma, Cheng-lin

2015-01-01

Afforestation, the conversion of non-forested land into forest, is widespread in China. However, the dynamics of soil organic carbon (SOC) after afforestation are not well understood, especially in plateau climate zones. For a total of 48 shrub- and/or tree-dominated afforestation sites on the Qinghai Plateau, Northwestern China, post-afforestation changes in SOC, total nitrogen (TN), the carbon-to-nitrogen ratio (C/N) and soil bulk density (BD) were investigated to a soil depth of 60 cm using the paired-plots method. SOC and TN accumulated at rates of 138.2 g C m(-2) yr(-1) and 4.6 g N m(-2) yr(-1), respectively, in shrub-dominated afforestation sites and at rates of 113.3 g C m(-2) yr(-1) and 6.7 g N m(-2) yr(-1), respectively, in tree-dominated afforestation sites. Soil BD was slightly reduced in all layers in the shrub-dominated afforestation plots, and significantly reduced in soil layers from 0-40cm in the tree-dominated afforestation plots. The C/N ratio was higher in afforested sites relative to the reference sites. SOC accumulation was closely related to TN accumulation following afforestation, and the inclusion of N-fixing species in tree-dominated afforestation sites additionally increased the soil accumulation capacity for SOC (p < 0.05). Multiple regression models including the age of an afforestation plot and total number of plant species explained 75% of the variation in relative SOC content change at depth of 0-20 cm, in tree-dominated afforestation sites. We conclude that afforestation on the Qinghai Plateau is associated with great capability of SOC and TN sequestration. This study improves our understanding of the mechanisms underlying SOC and TN accumulation in a plateau climate, and provides evidence on the C sequestration potentials associated with forestry projects in China.

Obstacles Related to Structuring for Mathematization Encountered by Students When Solving Physics Problems

ERIC Educational Resources Information Center

Niss, Martin

2017-01-01

This paper studies the cognitive obstacles related to one aspect of mathematization in physics problem-solving, namely, what might be called "structuring for mathematization," where the problem situation is structured in such a way that a translation to a mathematical universe can be done. We report the results of an analysis of four…

Is There a Causal Relation between Mathematical Creativity and Mathematical Problem-Solving Performance?

ERIC Educational Resources Information Center

Tyagi, Tarun Kumar

2016-01-01

The relationship between mathematical creativity (MC) and mathematical problem-solving performance (MP) has often been studied but the causal relation between these two constructs has yet to be clearly reported. The main purpose of this study was to define the causal relationship between MC and MP. Data from a representative sample of 480…

The Relation between Mathematics and Working Memory in Young Children with Fetal Alcohol Spectrum Disorders

ERIC Educational Resources Information Center

Rasmussen, Carmen; Bisanz, Jeffrey

2011-01-01

The goal of this study was to examine the relation between mathematics and working memory in young children with Fetal Alcohol Spectrum Disorders (FASD). Children with FASD and comparison children (4 to 6 years old) completed standardized tests of mathematics and working memory. Children with FASD showed impairments on mathematics (applied…

The Co-Development and Interrelation of Proof and Authority: The Case of Yana and Ronit

ERIC Educational Resources Information Center

Fried, Michael N.; Amit, Miriam

2008-01-01

Students' mathematical lives are characterized not only by a set of mathematical ideas and the engagement in mathematical thinking, but also by social relations, specifically, relations of authority. Watching student actions and speaking to students, one becomes cognizant of a "web of authority" ever present in mathematics classrooms. In…

Assessing Senior Secondary School Students' Mathematical Proficiency as Related to Gender and Performance in Mathematics in Nigeria

ERIC Educational Resources Information Center

Awofala, Adeneye O. A.

2017-01-01

The study investigated mathematical proficiency as related to gender and performance in mathematics among 400 Nigerian senior secondary school students from 10 elitist senior secondary schools in Lagos State using the quantitative research method within the blueprint of descriptive survey design. Data collected were analysed using the descriptive…

Assessing Preservice Teachers' Mathematics Cognitive Failures as Related to Mathematics Anxiety and Performance in Undergraduate Calculus

ERIC Educational Resources Information Center

Awofala, Adeneye O. A.; Odogwu, Helen N.

2017-01-01

The study investigated mathematics cognitive failures as related to mathematics anxiety, gender and performance in calculus among 450 preservice teachers from four public universities in the South West geo-political zone of Nigeria using the quantitative research method within the blueprint of the descriptive survey design. Data collected were…

Prospective Mathematics Teachers' Ability to Identify Mistakes Related to Angle Concept of Sixth Grade Students

ERIC Educational Resources Information Center

Arslan, Cigdem; Erbay, Hatice Nur; Guner, Pinar

2017-01-01

In the present study we try to highlight prospective mathematics teachers' ability to identify mistakes of sixth grade students related to angle concept. And also we examined prospective mathematics teachers' knowledge of angle concept. Study was carried out with 30 sixth-grade students and 38 prospective mathematics teachers. Sixth grade students…

The Characteristics of Mathematical Creativity

ERIC Educational Resources Information Center

Sriraman, Bharath

2004-01-01

Mathematical creativity ensures the growth of mathematics as a whole. However, the source of this growth, the creativity of the mathematician, is a relatively unexplored area in mathematics and mathematics education. In order to investigate how mathematicians create mathematics, a qualitative study involving five creative mathematicians was…

Examining Mathematics Anxiety in Elementary Classroom Teachers

ERIC Educational Resources Information Center

McAnallen, Rachel R.

2010-01-01

Test anxiety and mathematics anxiety have been found to relate to mathematics performance in both children and adults. This study investigated mathematics anxiety in elementary teachers and whether those who experience mathematics anxiety also have professional anxiety about teaching mathematics. A researcher-developed instrument called the…

Promoting Preservice Teachers' Mathematics Identity Exploration

ERIC Educational Resources Information Center

Heffernan, Kayla

2016-01-01

Despite the effort of teacher education programs, early childhood, and elementary preservice teachers often fear mathematics, have high mathematics anxiety, hold negative self-perceptions in relation to mathematics, find mathematics irrelevant, and have low mathematics achievement. The aim of this study was to implement and investigate the…

Declining resilience of ecosystem functions under biodiversity loss.

PubMed

Oliver, Tom H; Isaac, Nick J B; August, Tom A; Woodcock, Ben A; Roy, David B; Bullock, James M

2015-12-08

The composition of species communities is changing rapidly through drivers such as habitat loss and climate change, with potentially serious consequences for the resilience of ecosystem functions on which humans depend. To assess such changes in resilience, we analyse trends in the frequency of species in Great Britain that provide key ecosystem functions--specifically decomposition, carbon sequestration, pollination, pest control and cultural values. For 4,424 species over four decades, there have been significant net declines among animal species that provide pollination, pest control and cultural values. Groups providing decomposition and carbon sequestration remain relatively stable, as fewer species are in decline and these are offset by large numbers of new arrivals into Great Britain. While there is general concern about degradation of a wide range of ecosystem functions, our results suggest actions should focus on particular functions for which there is evidence of substantial erosion of their resilience.

Rodent Plasmodium-infected red blood cells: imaging their fates and interactions within their hosts.

PubMed

Claser, Carla; Malleret, Benoit; Peng, Kaitian; Bakocevic, Nadja; Gun, Sin Yee; Russell, Bruce; Ng, Lai Guan; Rénia, Laurent

2014-02-01

Malaria, a disease caused by the Plasmodium parasite, remains one of the most deadly infectious diseases known to mankind. The parasite has a complex life cycle, of which only the erythrocytic stage is responsible for the diverse pathologies induced during infection. To date, the disease mechanisms that underlie these pathologies are still poorly understood. In the case of infections caused by Plasmodium falciparum, the species responsible for most malaria related deaths, pathogenesis is thought to be due to the sequestration of infected red blood cells (IRBCs) in deep tissues. Other human and rodent malaria parasite species are also known to exhibit sequestration. Here, we review the different techniques that allow researchers to study how rodent malaria parasites modify their host cells, the distribution of IRBCs in vivo as well as the interactions between IRBCs and host tissues. © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

Predicting Children's Reading and Mathematics Achievement from Early Quantitative Knowledge and Domain-General Cognitive Abilities

PubMed Central

Chu, Felicia W.; vanMarle, Kristy; Geary, David C.

2016-01-01

One hundred children (44 boys) participated in a 3-year longitudinal study of the development of basic quantitative competencies and the relation between these competencies and later mathematics and reading achievement. The children's preliteracy knowledge, intelligence, executive functions, and parental educational background were also assessed. The quantitative tasks assessed a broad range of symbolic and nonsymbolic knowledge and were administered four times across 2 years of preschool. Mathematics achievement was assessed at the end of each of 2 years of preschool, and mathematics and word reading achievement were assessed at the end of kindergarten. Our goals were to determine how domain-general abilities contribute to growth in children's quantitative knowledge and to determine how domain-general and domain-specific abilities contribute to children's preschool mathematics achievement and kindergarten mathematics and reading achievement. We first identified four core quantitative competencies (e.g., knowledge of the cardinal value of number words) that predict later mathematics achievement. The domain-general abilities were then used to predict growth in these competencies across 2 years of preschool, and the combination of domain-general abilities, preliteracy skills, and core quantitative competencies were used to predict mathematics achievement across preschool and mathematics and word reading achievement at the end of kindergarten. Both intelligence and executive functions predicted growth in the four quantitative competencies, especially across the first year of preschool. A combination of domain-general and domain-specific competencies predicted preschoolers' mathematics achievement, with a trend for domain-specific skills to be more strongly related to achievement at the beginning of preschool than at the end of preschool. Preschool preliteracy skills, sensitivity to the relative quantities of collections of objects, and cardinal knowledge predicted reading and mathematics achievement at the end of kindergarten. Preliteracy skills were more strongly related to word reading, whereas sensitivity to relative quantity was more strongly related to mathematics achievement. The overall results indicate that a combination of domain-general and domain-specific abilities contribute to development of children's early mathematics and reading achievement. PMID:27252675

Predicting Children's Reading and Mathematics Achievement from Early Quantitative Knowledge and Domain-General Cognitive Abilities.

PubMed

Chu, Felicia W; vanMarle, Kristy; Geary, David C

2016-01-01

One hundred children (44 boys) participated in a 3-year longitudinal study of the development of basic quantitative competencies and the relation between these competencies and later mathematics and reading achievement. The children's preliteracy knowledge, intelligence, executive functions, and parental educational background were also assessed. The quantitative tasks assessed a broad range of symbolic and nonsymbolic knowledge and were administered four times across 2 years of preschool. Mathematics achievement was assessed at the end of each of 2 years of preschool, and mathematics and word reading achievement were assessed at the end of kindergarten. Our goals were to determine how domain-general abilities contribute to growth in children's quantitative knowledge and to determine how domain-general and domain-specific abilities contribute to children's preschool mathematics achievement and kindergarten mathematics and reading achievement. We first identified four core quantitative competencies (e.g., knowledge of the cardinal value of number words) that predict later mathematics achievement. The domain-general abilities were then used to predict growth in these competencies across 2 years of preschool, and the combination of domain-general abilities, preliteracy skills, and core quantitative competencies were used to predict mathematics achievement across preschool and mathematics and word reading achievement at the end of kindergarten. Both intelligence and executive functions predicted growth in the four quantitative competencies, especially across the first year of preschool. A combination of domain-general and domain-specific competencies predicted preschoolers' mathematics achievement, with a trend for domain-specific skills to be more strongly related to achievement at the beginning of preschool than at the end of preschool. Preschool preliteracy skills, sensitivity to the relative quantities of collections of objects, and cardinal knowledge predicted reading and mathematics achievement at the end of kindergarten. Preliteracy skills were more strongly related to word reading, whereas sensitivity to relative quantity was more strongly related to mathematics achievement. The overall results indicate that a combination of domain-general and domain-specific abilities contribute to development of children's early mathematics and reading achievement.

Toward optimal soil organic carbon sequestration with effects of agricultural management practices and climate change in Tai-Lake paddy soils of China

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Liming; Zhuang, Qianlai; He, Yujie

Understanding the impacts of climate change and agricultural management practices on soil organic carbon (SOC) dynamics is critical for implementing optimal farming practices and maintaining agricultural productivity. This study examines the influence of climate and agricultural management on carbon sequestration potentials in Tai-Lake Paddy soils of China using the DeNitrification-DeComposition (DNDC) model, with a high-resolution soil database (1:50,000). Model simulations considered the effects of no tillage, increasing manure application, increasing/decreasing of N-fertilizer application and crop residues, water management, and climatic shifts in temperature and precipitation. We found that the carbon sequestration potential for the 2.32 Mha paddy soils of themore » Tai-Lake region varied from 4.71 to 44.31 Tg C during the period 2001-2019, with an annual average SOC changes ranged from 107 to 1005 kg C ha -1 yr -1. The sequestration potential significantly increased with increasing application of N-fertilizer, manure, conservation tillage, and crop residues. To increase soil C sequestration in this region, no-tillage and increasing of crop residue return to soils and manure application are recommended. Our analysis of climate impacts on SOC sequestration suggests that the rice paddies in this region will continue to be a carbon sink under future warming conditions. In addition, because the region’s annual precipitation (>1200 mm) is high, we also recommend reducing irrigation water use for these rice paddies to conserve freshwater in the Tai-Lake region.« less

Pilot Studies of Geologic and Terrestrial Carbon Sequestration in the Big Sky Region, USA, and Opportunities for Commercial Scale Deployment of New Technologies

NASA Astrophysics Data System (ADS)

Waggoner, L. A.; Capalbo, S. M.; Talbott, J.

2007-05-01

Within the Big Sky region, including Montana, Idaho, South Dakota, Wyoming and the Pacific Northwest, industry is developing new coal-fired power plants using the abundant coal and other fossil-based resources. Of crucial importance to future development programs are robust carbon mitigation plans that include a technical and economic assessment of regional carbon sequestration opportunities. The objective of the Big Sky Carbon Sequestration Partnership (BSCSP) is to promote the development of a regional framework and infrastructure required to validate and deploy carbon sequestration technologies. Initial work compiled sources and potential sinks for carbon dioxide (CO2) in the Big Sky Region and developed the online Carbon Atlas. Current efforts couple geologic and terrestrial field validation tests with market assessments, economic analysis and regulatory and public outreach. The primary geological efforts are in the demonstration of carbon storage in mafic/basalt formations, a geology not yet well characterized but with significant long-term storage potential in the region and other parts of the world; and in the Madison Formation, a large carbonate aquifer in Wyoming and Montana. Terrestrial sequestration relies on management practices and technologies to remove atmospheric CO2 to storage in trees, plants, and soil. This indirect sequestration method can be implemented today and is on the front-line of voluntary, market-based approaches to reduce CO2 emissions. Details of pilot projects are presented including: new technologies, challenges and successes of projects and potential for commercial-scale deployment.

Development of an assessment methodology for hydrocarbon recovery potential using carbon dioxide and associated carbon sequestration-Workshop findings

USGS Publications Warehouse

Verma, Mahendra K.; Warwick, Peter D.

2011-01-01

The Energy Independence and Security Act of 2007 (Public Law 110-140) authorized the U.S. Geological Survey (USGS) to conduct a national assessment of geologic storage resources for carbon dioxide (CO2) and requested that the USGS estimate the "potential volumes of oil and gas recoverable by injection and sequestration of industrial carbon dioxide in potential sequestration formations" (121 Stat. 1711). The USGS developed a noneconomic, probability-based methodology to assess the Nation's technically assessable geologic storage resources available for sequestration of CO2 (Brennan and others, 2010) and is currently using the methodology to assess the Nation's CO2 geologic storage resources. Because the USGS has not developed a methodology to assess the potential volumes of technically recoverable hydrocarbons that could be produced by injection and sequestration of CO2, the Geologic Carbon Sequestration project initiated an effort in 2010 to develop a methodology for the assessment of the technically recoverable hydrocarbon potential in the sedimentary basins of the United States using enhanced oil recovery (EOR) techniques with CO2 (CO2-EOR). In collaboration with Stanford University, the USGS hosted a 2-day CO2-EOR workshop in May 2011, attended by 28 experts from academia, natural resource agencies and laboratories of the Federal Government, State and international geologic surveys, and representatives from the oil and gas industry. The geologic and the reservoir engineering and operations working groups formed during the workshop discussed various aspects of geology, reservoir engineering, and operations to make recommendations for the methodology.

Economic analysis of secondary and enhanced oil recovery techniques in Wyoming

NASA Astrophysics Data System (ADS)

Kara, Erdal

This dissertation primarily aims to theoretically analyze a firm's optimization of enhanced oil recovery (EOR) and carbon dioxide sequestration under different social policies and empirically analyze the firm's optimization of enhanced oil recovery. The final part of the dissertation empirically analyzes how geological factors and water injection management influence oil recovery. The first chapter builds a theoretical model to analyze economic optimization of EOR and geological carbon sequestration under different social policies. Specifically, it analyzes how social policies on sequestration influence the extent of oil operations, optimal oil production and CO2 sequestration. The theoretical results show that the socially optimal policy is a subsidy on the net CO2 sequestration, assuming negative net emissions from EOR. Such a policy is expected to increase a firm's total carbon dioxide sequestration. The second chapter statistically estimates the theoretical oil production model and its different versions. Empirical results are not robust over different estimation techniques and not in line with the theoretical production model. The last part of the second chapter utilizes a simplified version of theoretical model and concludes that EOR via CO2 injection improves oil recovery. The final chapter analyzes how a contemporary oil recovery technology (water flooding of oil reservoirs) and various reservoir-specific geological factors influence oil recovery in Wyoming. The results show that there is a positive concave relationship between cumulative water injection and cumulative oil recovery and also show that certain geological factors affect the oil recovery. Moreover, the curvature of the concave functional relationship between cumulative water injection and oil recovery is reservoir-specific due to heterogeneities among different reservoirs.

Using confirmatory factor analysis to understand executive control in preschool children: sources of variation in emergent mathematic achievement

PubMed Central

Bull, Rebecca; Espy, Kimberly Andrews; Wiebe, Sandra A.; Sheffield, Tiffany D.; Nelson, Jennifer Mize

2010-01-01

Latent variable modeling methods have demonstrated utility for understanding the structure of executive control (EC) across development. These methods are utilized to better characterize the relation between EC and mathematics achievement in the preschool period, and to understand contributing sources of individual variation. Using the sample and battery of laboratory tasks described in Wiebe, Espy and Charak (2008), latent EC was related strongly to emergent mathematics achievement in preschool, and was robust after controlling for crystallized intellectual skills. The relation between crystallized skills and emergent mathematics differed between girls and boys, although the predictive association between EC and mathematics did not. Two dimensions of the child’s social environment contributed to mathematics achievement: social network support through its relation to EC and environmental stressors through its relation with crystallized skills. These findings underscore the need to examine the dimensions, mechanisms, and individual pathways that influence the development of early competence in basic cognitive processes that underpin early academic achievement. PMID:21676089

Using confirmatory factor analysis to understand executive control in preschool children: sources of variation in emergent mathematic achievement.

PubMed

Bull, Rebecca; Espy, Kimberly Andrews; Wiebe, Sandra A; Sheffield, Tiffany D; Nelson, Jennifer Mize

2011-07-01

Latent variable modeling methods have demonstrated utility for understanding the structure of executive control (EC) across development. These methods are utilized to better characterize the relation between EC and mathematics achievement in the preschool period, and to understand contributing sources of individual variation. Using the sample and battery of laboratory tasks described in Wiebe, Espy and Charak (2008), latent EC was related strongly to emergent mathematics achievement in preschool, and was robust after controlling for crystallized intellectual skills. The relation between crystallized skills and emergent mathematics differed between girls and boys, although the predictive association between EC and mathematics did not. Two dimensions of the child 's social environment contributed to mathematics achievement: social network support through its relation to EC and environmental stressors through its relation with crystallized skills. These findings underscore the need to examine the dimensions, mechanisms, and individual pathways that influence the development of early competence in basic cognitive processes that underpin early academic achievement. © 2010 Blackwell Publishing Ltd.

Mathematics is differentially related to reading comprehension and word decoding: Evidence from a genetically-sensitive design

PubMed Central

Harlaar, Nicole; Kovas, Yulia; Dale, Philip S.; Petrill, Stephen A.; Plomin, Robert

2013-01-01

Although evidence suggests that individual differences in reading and mathematics skills are correlated, this relationship has typically only been studied in relation to word decoding or global measures of reading. It is unclear whether mathematics is differentially related to word decoding and reading comprehension. The current study examined these relationships at both a phenotypic and etiological level in a population-based cohort of 5162 twin pairs at age 12. Multivariate genetic analyses of latent phenotypic factors of mathematics, word decoding and reading comprehension revealed substantial genetic and shared environmental correlations among all three domains. However, the phenotypic and genetic correlations between mathematics and reading comprehension were significantly greater than between mathematics and word decoding. Independent of mathematics, there was also evidence for genetic and nonshared environmental links between word decoding and reading comprehension. These findings indicate that word decoding and reading comprehension have partly distinct relationships with mathematics in the middle school years. PMID:24319294

Mathematics is differentially related to reading comprehension and word decoding: Evidence from a genetically-sensitive design.

PubMed

Harlaar, Nicole; Kovas, Yulia; Dale, Philip S; Petrill, Stephen A; Plomin, Robert

2012-08-01

Although evidence suggests that individual differences in reading and mathematics skills are correlated, this relationship has typically only been studied in relation to word decoding or global measures of reading. It is unclear whether mathematics is differentially related to word decoding and reading comprehension. The current study examined these relationships at both a phenotypic and etiological level in a population-based cohort of 5162 twin pairs at age 12. Multivariate genetic analyses of latent phenotypic factors of mathematics, word decoding and reading comprehension revealed substantial genetic and shared environmental correlations among all three domains. However, the phenotypic and genetic correlations between mathematics and reading comprehension were significantly greater than between mathematics and word decoding. Independent of mathematics, there was also evidence for genetic and nonshared environmental links between word decoding and reading comprehension. These findings indicate that word decoding and reading comprehension have partly distinct relationships with mathematics in the middle school years.

The planetary water drama: Dual task of feeding humanity and curbing climate change

NASA Astrophysics Data System (ADS)

Rockström, J.; Falkenmark, M.; Lannerstad, M.; Karlberg, L.

2012-08-01

This paper analyses the potential conflict between resilience of the Earth system and global freshwater requirements for the dual task of carbon sequestration to reduce CO2 in the atmosphere, and food production to feed humanity by 2050. It makes an attempt to assess the order of magnitude of the increased consumptive water use involved and analyses the implications as seen from two parallel perspectives; the global perspective of human development within a “safe operating space” with regard to the definition of the Planetary Boundary for freshwater; and the social-ecological implications at the regional river basin scale in terms of sharpening water shortages and threats to aquatic ecosystems. The paper shows that the consumptive water use involved in the dual task would both transgress the proposed planetary boundary range for global consumptive freshwater use and would further exacerbate already severe river depletion, causing societal problems related to water shortage and water allocation. Thus, strategies to rely on sequestration of CO2 as a mitigation strategy must recognize the high freshwater costs involved, implying that the key climate mitigation strategy must be to reduce emissions. The paper finally highlights the need to analyze both water and carbon tradeoffs from anticipated large scale biofuel production climate change mitigation strategy, to reveal gains and impact of this in contrast to carbon sequestration strategies.

Preschool children's mathematical knowledge: The effect of teacher "math talk.".

PubMed

Klibanoff, Raquel S; Levine, Susan C; Huttenlocher, Janellen; Vasilyeva, Marina; Hedges, Larry V

2006-01-01

This study examined the relation between the amount of mathematical input in the speech of preschool or day-care teachers and the growth of children's conventional mathematical knowledge over the school year. Three main findings emerged. First, there were marked individual differences in children's conventional mathematical knowledge by 4 years of age that were associated with socioeconomic status. Second, there were dramatic differences in the amount of math-related talk teachers provided. Third, and most important, the amount of teachers' math-related talk was significantly related to the growth of preschoolers' conventional mathematical knowledge over the school year but was unrelated to their math knowledge at the start of the school year. Copyright 2006 APA, all rights reserved.

Briefing on geological sequestration

EPA Science Inventory

Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media – primarily saline formations, depleted or nearly depleted oil and gas...

Sequestrate fungi of New Zealand: Elaphomyces (Ascomycota, Eurotiales, Elaphomycetaceae)

Treesearch

Michael A. Castellano; Ross E. Beever; James M. Trappe

2012-01-01

Four species of the sequestrate fungal genus Elaphomyces are reported from New Zealand: Elaphomyces bollardii sp. nov. associated with Leptospermum spp. and Kunzea ericoides, E. luteicrustus sp. nov. associated with Nothofagus menziesii, E. putridus sp. nov. associated with...

[Assessment on the availability of nitrogen fertilization in improving carbon sequestration potential of China's cropland soil].

PubMed

Lu, Fei; Wang, Xiao-Ke; Han, Bing; Ouyang, Zhi-Yun; Duan, Xiao-Nan; Zheng, Hua

2008-10-01

With reference to the situation of nitrogen fertilization in 2003 and the recommendations from agricultural experts on fertilization to different crops, two scenarios, namely, 'current situation' and 'fertilization as recommended', were set for estimating the current and potential carbon sequestration of China's cropland soil under nitrogen fertilization. After collecting and analyzing the typical data from the long-term agricultural experiment stations all over China, and based on the recent studies of soil organic matter and nutrient dynamics, we plotted China into four agricultural regions, and estimated the carbon sequestration rate and potential of cropland soil under the two scenarios in each province of China. Meanwhile, with the data concerning fossil fuel consumption for fertilizer production and nitrogen fertilization, the greenhouse gas leakage caused by nitrogen fertilizer production and application was estimated with the help of the parameters given by domestic studies and IPCC. We further proposed that the available carbon sequestration potential of cropland soil could be taken as the criterion of the validity and availability of carbon sequestration measures. The results showed that the application of synthetic nitrogen fertilizer could bring about a carbon sequestration potential of 21.9 Tg C x a(-1) in current situation, and 30.2 Tg C x a(-1) with fertilization as recommended. However, under the two scenarios, the greenhouse gas leakage caused by fertilizer production and application would reach 72.9 Tg C x a(-1) and 91.4 Tg C x a(-1), and thus, the actual available carbon sequestration potential would be -51.0 Tg C x a(-1) and -61.1 Tg C x a(-1), respectively. The situation was even worse under the 'fertilization as recommended' scenario, because the increase in the amount of nitrogen fertilization would lead to 10. 1 Tg C x a(-1) or more net greenhouse gas emission. All these results indicated that the application of synthetic nitrogen fertilizer could not be taken as a feasible measure for the carbon sequestration of cropland soil in China. Since synthetic fertilizer application is the basic guarantee of China's crop production, it was suggested to increase the efficiency of synthetic nitrogen fertilizer, and at the same time, to cut down the synthetic nitrogen fertilizer production and its application on the premise that the crop yield should be ensured.

[Carbon sequestration in soil particle-sized fractions during reversion of desertification at Mu Us Sand land.

PubMed

Ma, Jian Ye; Tong, Xiao Gang; Li, Zhan Bin; Fu, Guang Jun; Li, Jiao; Hasier

2016-11-18

The aim of this study was to investigate the effects of carbon sequestration in soil particle-sized fractions during reversion of desertification at Mu Us Sand Land, soil samples were collected from quicksand land, semifixed sand and fixed sand lands that were established by the shrub for 20-55 year-old and the arbor for 20-50 year-old at sand control region of Yulin in Northern Shaanxi Province. The dynamics and sequestration rate of soil organic carbon (SOC) associated with sand, silt and clay were measured by physical fractionation method. The results indicated that, compared with quicksand area, the carbon content in total SOC and all soil particle-sized fractions at bothsand-fixing sand forest lands showed a significant increasing trend, and the maximum carbon content was observed in the top layer of soils. From quicksand to fixed sand land with 55-year-old shrub and 50-year-old arbor, the annual sequestration rate of carbon stock in 0-5 cm soil depth was same in silt by 0.05 Mg·hm -2 ·a -1 . The increase rate of carbon sequestration in sand was 0.05 and 0.08 Mg·hm -2 ·a -1 , and in clay was 0.02 and 0.03 Mg·hm -2 ·a -1 at shrubs and arbors land, respectively. The increase rate of carbon sequestration in 0-20 cm soil layer for all the soil particles was averagely 2.1 times as that of 0-5 cm. At the annual increase rate of carbon, the stock of carbon in sand, silt and clay at the two fixed sand lands were increased by 6.7, 18.1 and 4.4 times after 50-55 year-old reversion of quicksand land to fixed sand. In addition, the average percentages that contributed to accumulation of total SOC by different particles in 0-20 cm soil were in the order of silt carbon (39.7%)≈sand carbon (34.6%) > clay carbon (25.6%). Generally, the soil particle-sized fractions had great carbon sequestration potential during reversion of desertification in Mu Us Sand Land, and the slit and sand were the main fractions for carbon sequestration at both fixed sand lands.

Development of a 1 x N Fiber Optic Sensor Array for Carbon Sequestration Site Monitoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Repasky, Kevin

2014-02-01

A fiber sensor array for sub-surface CO 2 concentrations measurements was developed for monitoring geologic carbon sequestration sites. The fiber sensor array uses a single temperature tunable distributed feedback (DFB) laser operating with a nominal wavelength of 2.004 μm. Light from this DFB laser is direct to one of the 4 probes via an in-line 1 x 4 fiber optic switch. Each of the 4 probes are buried and allow the sub-surface CO 2 to enter the probe through Millipore filters that allow the soil gas to enter the probe but keeps out the soil and water. Light from themore » DFB laser interacts with the CO 2 before it is directed back through the in-line fiber optic switch. The DFB laser is tuned across two CO 2 absorption features where a transmission measurement is made allowing the CO 2 concentration to be retrieved. The fiber optic switch then directs the light to the next probe where this process is repeated allowing sub-surface CO 2 concentration measurements at each of the probes to be made as a function of time. The fiber sensor array was deployed for fifty-eight days beginning June 19, 2012 at the Zero Emission Research Technology (ZERT) field site where sub-surface CO 2 concentrations were monitored. Background measurements indicate the fiber sensor array can monitor background levels as low as 1,000 parts per million (ppm). A thirty four day sub-surface release of 0.15 tones CO 2/day began on July 10, 2012. The elevated subsurface CO 2 concentration was easily detected by each of the four probes with values ranging to over 60,000 ppm, a factor of greater than 6 higher than background measurements. The fiber sensor array was also deploy at the Big Sky Carbon Sequestration Partnership (BSCSP) site in north-central Montana between July 9th and August 7th, 2013 where background measurements were made in a remote sequestration site with minimal infrastructure. The project provided opportunities for two graduate students to participate in research directly related to geologic carbon sequestration. Furthermore, commercialization of the technology developed is being pursued with five different companies via the Department of energy SBIR/STTR program« less

Orientations toward Mathematical Processes of Prospective Secondary Mathematics Teachers as Related to Work with Tasks

ERIC Educational Resources Information Center

Cannon, Tenille

2016-01-01

Mathematics can be conceptualized in different ways. Policy documents such as the National Council of Teachers of Mathematics (NCTM) (2000) and the Common Core State Standards Initiative (CCSSI) (2010), classify mathematics in terms of mathematical content (e.g., quadratic functions, Pythagorean theorem) and mathematical activity in the form of…

Examining Relations between Mathematics Teachers' Instructional Vision and Knowledge and Change in Practice

ERIC Educational Resources Information Center

Munter, Charles; Correnti, Richard

2017-01-01

This article provides a longitudinal examination of how changes in more than 200 middle-grades mathematics teachers' instructional practices related to their (a) mathematical knowledge for teaching (MKT) and (b) instructional vision. Results of this multilevel regression analysis suggest that MKT and instructional vision are related to instruction…

Self-Concept Mediates the Relation between Achievement and Emotions in Mathematics

ERIC Educational Resources Information Center

Van der Beek, Jojanneke P. J.; Van der Ven, Sanne H. G.; Kroesbergen, Evelyn H.; Leseman, Paul P. M.

2017-01-01

Background: Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions. Aims: The aims were (1) to investigate the…

Relating Difficulty in School Mathematics to Nature of Mathematics: Perception of High School Students from Kerala

ERIC Educational Resources Information Center

Gafoor, Kunnathodi Abdul; Sarabi, M. K.

2015-01-01

This study relates factors in nature of Mathematics and its teaching learning to student difficulties for diverse mathematics tasks. Descriptive survey was done on a sample of 300 high school students in Kerala with a questionnaire on difficulties in learning. Student perception of difficulty on 26 types of tasks, under five heads that students…

Intentional and automatic numerical processing as predictors of mathematical abilities in primary school children

PubMed Central

Pina, Violeta; Castillo, Alejandro; Cohen Kadosh, Roi; Fuentes, Luis J.

2015-01-01

Previous studies have suggested that numerical processing relates to mathematical performance, but it seems that such relationship is more evident for intentional than for automatic numerical processing. In the present study we assessed the relationship between the two types of numerical processing and specific mathematical abilities in a sample of 109 children in grades 1–6. Participants were tested in an ample range of mathematical tests and also performed both a numerical and a size comparison task. The results showed that numerical processing related to mathematical performance only when inhibitory control was involved in the comparison tasks. Concretely, we found that intentional numerical processing, as indexed by the numerical distance effect in the numerical comparison task, was related to mathematical reasoning skills only when the task-irrelevant dimension (the physical size) was incongruent; whereas automatic numerical processing, indexed by the congruency effect in the size comparison task, was related to mathematical calculation skills only when digits were separated by small distance. The observed double dissociation highlights the relevance of both intentional and automatic numerical processing in mathematical skills, but when inhibitory control is also involved. PMID:25873909

The relationship among mathematics anxiety, beliefs about mathematics, mathematics self-efficacy, and mathematics performance in associate degree nursing students.

PubMed

Walsh, Kathleen A

2008-01-01

This research explored nursing students' mathematics anxiety, beliefs about mathematics, and mathematics self-efficacy in relation to performance on a medication mathematics test. Results revealed that the participants experienced some mathematics anxiety and had positive beliefs about mathematics and mathematics self-efficacy. Qualitative responses indicated that participants worried about the consequences of failing the medication mathematics test and that practice helped reduce this anxiety. In addition, participants acknowledged the importance of correct dosage calculations for nursing practice. Implications for nursing education are discussed.

The Mathematics Education Debates: Preparing Students to Become Professionally Active Mathematics Teachers

ERIC Educational Resources Information Center

Munakata, Mika

2010-01-01

The Mathematics Education Debate is an assignment designed for and implemented in an undergraduate mathematics methods course for prospective secondary school mathematics teachers. For the assignment, students read and analyze current research and policy reports related to mathematics education, prepare and present their positions, offer…

Mathematization Competencies of Pre-Service Elementary Mathematics Teachers in the Mathematical Modelling Process

ERIC Educational Resources Information Center

Yilmaz, Suha; Tekin-Dede, Ayse

2016-01-01

Mathematization competency is considered in the field as the focus of modelling process. Considering the various definitions, the components of the mathematization competency are determined as identifying assumptions, identifying variables based on the assumptions and constructing mathematical model/s based on the relations among identified…

State and trait effects on individual differences in children's mathematical development.

PubMed

Bailey, Drew H; Watts, Tyler W; Littlefield, Andrew K; Geary, David C

2014-11-01

Substantial longitudinal relations between children's early mathematics achievement and their much later mathematics achievement are firmly established. These findings are seemingly at odds with studies showing that early educational interventions have diminishing effects on children's mathematics achievement across time. We hypothesized that individual differences in children's later mathematical knowledge are more an indicator of stable, underlying characteristics related to mathematics learning throughout development than of direct effects of early mathematical competency on later mathematical competency. We tested this hypothesis in two longitudinal data sets, by simultaneously modeling effects of latent traits (stable characteristics that influence learning across time) and states (e.g., prior knowledge) on children's mathematics achievement over time. Latent trait effects on children's mathematical development were substantially larger than state effects. Approximately 60% of the variance in trait mathematics achievement was accounted for by commonly used control variables, such as working memory, but residual trait effects remained larger than state effects. Implications for research and practice are discussed. © The Author(s) 2014.

State and Trait Effects on Individual Differences in Children's Mathematical Development

PubMed Central

Bailey, Drew H.; Watts, Tyler W.; Littlefield, Andrew K.; Geary, David C.

2015-01-01

Substantial longitudinal relations between children's early mathematics achievement and their much later mathematics achievement are firmly established. These findings are seemingly at odds with studies showing that early educational interventions have diminishing effects on children's mathematics achievement across time. We hypothesized that individual differences in children's later mathematical knowledge are more an indicator of stable, underlying characteristics related to mathematics learning throughout development than of direct effects of early mathematical competency on later mathematical competency. We tested this hypothesis in two longitudinal data sets, by simultaneously modeling effects of latent traits (stable characteristics that influence learning across time) and states (e.g., prior knowledge) on children's mathematics achievement over time. Latent trait effects on children's mathematical development were substantially larger than state effects. Approximately 60% of the variance in trait mathematics achievement was accounted for by commonly used control variables, such as working memory, but residual trait effects remained larger than state effects. Implications for research and practice are discussed. PMID:25231900

Briefing on geological sequestration (Tulsa)

EPA Science Inventory

Geological sequestration (GS) is generally recognized as the injection and long-term (e.g., hundreds to thousands of years) trapping of gaseous, liquid or supercritical carbon dioxide (CO2) in subsurface media – primarily saline formations, depleted or nearly depleted oil and gas...

Optimizing root system architecture in biofuel crops for sustainable energy production and soil carbon sequestration.

PubMed

To, Jennifer Pc; Zhu, Jinming; Benfey, Philip N; Elich, Tedd

2010-09-08

Root system architecture (RSA) describes the dynamic spatial configuration of different types and ages of roots in a plant, which allows adaptation to different environments. Modifications in RSA enhance agronomic traits in crops and have been implicated in soil organic carbon content. Together, these fundamental properties of RSA contribute to the net carbon balance and overall sustainability of biofuels. In this article, we will review recent data supporting carbon sequestration by biofuel crops, highlight current progress in studying RSA, and discuss future opportunities for optimizing RSA for biofuel production and soil carbon sequestration.

[Effects of straw returning combined with medium and microelements application on soil organic carbon sequestration in cropland.

PubMed

Jiang, Zhen Hui; Shi, Jiang Lan; Jia, Zhou; Ding, Ting Ting; Tian, Xiao Hong

2016-04-22

A 52-day incubation experiment was conducted to investigate the effects of maize straw decomposition with combined medium element (S) and microelements (Fe and Zn) application on arable soil organic carbon sequestration. During the straw decomposition, the soil microbial biomass carbon (MBC) content and CO 2 -C mineralization rate increased with the addition of S, Fe and Zn, respectively. Also, the cumulative CO 2 -C efflux after 52-day laboratory incubation significantly increased in the treatments with S, or Fe, or Zn addition, while there was no significant reduction of soil organic carbon content in the treatments. In addition, Fe or Zn application increased the inert C pools and their proportion, and apparent balance of soil organic carbon, indicating a promoting effect of Fe or Zn addition on soil organic carbon sequestration. In contrast, S addition decreased the proportion of inert C pools and apparent balance of soil organic carbon, indicating an adverse effect of S addition on soil organic carbon sequestration. The results suggested that when nitrogen and phosphorus fertilizers were applied, inclusion of S, or Fe, or Zn in straw incorporation could promote soil organic carbon mineralization process, while organic carbon sequestration was favored by Fe or Zn addition, but not by S addition.

Algae-Based Carbon Sequestration

NASA Astrophysics Data System (ADS)

Haoyang, Cai

2018-03-01

Our civilization is facing a series of environmental problems, including global warming and climate change, which are caused by the accumulation of green house gases in the atmosphere. This article will briefly analyze the current global warming problem and propose a method that we apply algae cultivation to absorb carbon and use shellfish to sequestrate it. Despite the importance of decreasing CO2 emissions or developing carbon-free energy sources, carbon sequestration should be a key issue, since the amount of carbon dioxide that already exists in the atmosphere is great enough to cause global warming. Algae cultivation would be a good choice because they have high metabolism rates and provides shellfish with abundant food that contains carbon. Shellfish’s shells, which are difficult to be decomposed, are reliable storage of carbon, compared to dead organisms like trees and algae. The amount of carbon that can be sequestrated by shellfish is considerable. However, the sequestrating rate of algae and shellfish is not high enough to affect the global climate. Research on algae and shellfish cultivation, including gene technology that aims to create “super plants” and “super shellfish”, is decisive to the solution. Perhaps the baton of history will shift to gene technology, from nuclear physics that has lost appropriate international environment after the end of the Cold War. Gene technology is vital to human survival.

Foundations of mathematics and literacy: The role of executive functioning components.

PubMed

Purpura, David J; Schmitt, Sara A; Ganley, Colleen M

2017-01-01

The current study investigated the relations between the three cognitive processes that comprise executive functioning (EF)-response inhibition, working memory, and cognitive flexibility-and individual components of mathematics and literacy skills in preschool children. Participants were 125 preschool children ranging in age from 3.12 to 5.26years (M=4.17years, SD=0.58). Approximately 53.2% were female, and the sample was predominantly Caucasian (69.8%). Results suggest that the components of EF may be differentially related to the specific components of early mathematics and literacy. For mathematics, response inhibition was broadly related to most components. Working memory was related to more advanced mathematics skills that involve comparison or combination of numbers and quantities. Cognitive flexibility was related to more conceptual or abstract mathematics skills. For early literacy, response inhibition and cognitive flexibility were related to print knowledge, and working memory was related only to phonological awareness. None of the EF components was related to vocabulary. These findings provide initial evidence for better understanding the ways in which EF components and academic skills are related and measured. Furthermore, the findings provide a foundation for further study of the components of each domain using a broader and more diverse array of measures. Copyright © 2016 Elsevier Inc. All rights reserved.

Land management effects on near-surface soil properties of southern U.S. coastal plain kandiudults.

Treesearch

M. Levi; J. Shaw; C. Wood; S. Herman; E. Carter; Y. Feng

2010-01-01

A comparative assessment of land management systems and relatively undisturbed ecosystems is useful for evaluating anthropogenic impacts on soil properties (Larson and Pierce, 1994). Such information is useful for the restoration and evaluation of C sequestration potential. Comparison of disturbed with natural ecosystems allows the measurement of soil properties...

Effect of thinning on partitioning of aboveground biomass in naturally regenerated shortleaf pine (Pinus echinata mill.)

Treesearch

Charles O. Sabatia; Rodney E. Will; Thomas B. Lynch

2010-01-01

In traditional harvesting systems, yield of forest stands may increase if a greater proportion of net primary production is allocated to bole wood. However, for management related to whole-tree harvesting, carbon sequestration, biofuels, and wildland fire avoidance, assessments of biomass partitioning to all aboveground components is needed. Thinning increases bole...

The carbon consequences of thinning techniques: stand structure makes a difference

Treesearch

Coeli Hoover; Susan Stout

2007-01-01

Using results from a 25-year study of thinning in a northwestern Pennsylvania Allegheny hardwood stand, we assess whether and how thinning method affected carbon sequestration and merchantable volume production. Plots were thinned to similar residual relative density by removing trees from different portions of the diameter distribution. Plots that were thinned from...

40 CFR 180.920 - Inert ingredients used pre-harvest; exemptions from the requirement of a tolerance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Defoamer γ-Butyrolactone Solvent C.I. Pigment Blue #15 (CAS Reg. No. 147-14-8; containing no more than 50... Surfactants, related adjuvants of surfactants Aluminum sulfate Safener adjuvant Ammonium chloride (CAS Reg. No... herbicides Ammonium polyphosphate (CAS Reg. No. 68333-79-9) Sequestrant, buffer, or surfactant Barium sulfate...

Carbon Sequestration in loblolly pine plantations: Methods, limitations, and research needs for estimating storage pools

Treesearch

Kurt Johnsen; Bob Teskey; Lisa Samuelson; John Butnor; David Sampson; Felipe Sanchez; Chris Maier; Steve McKeand

2004-01-01

Globally, the species most widely used for plantation forestry is loblolly pine (Pinus taeda L.). Because loblolly pine plantations are so extensive and grow so rapidly, they provide a great potential for sequestering atmospheric carbon (C). Because loblolly pine plantations are relatively simple ecosystems and because such a great volume of...

Spatial variation in the storages and age-related dynamics of forest carbon sequestration in different climate zones-evidence from black locust plantations on the Loess Plateau of China.

PubMed

Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

2015-01-01

Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China's Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha-1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha-1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha-1 to 28.4 Mg C ha-1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration.

Spatial Variation in the Storages and Age-Related Dynamics of Forest Carbon Sequestration in Different Climate Zones—Evidence from Black Locust Plantations on the Loess Plateau of China

PubMed Central

Li, Taijun; Ren, Bowen; Wang, Dahui; Liu, Guobin

2015-01-01

Knowledge about the long-term influences of climate change on the amount of potential carbon (C) sequestration in forest ecosystems, including age-related dynamics, remains unclear. This study used two similar age-sequences of black locust forests (Robinia pseudoacacia L.) in the semi-arid and semi-humid zones of China’s Loess Plateau to assess the variation in C stocks and age-related dynamics. Our results demonstrated that black locust forests of the semi-humid zone stored significantly more C than did forests in the semi-arid zone, across the chronosequence (p < 0.001). The C carrying capacity of the plantations was measured at 166.4 Mg C ha−1 (1 Mg = 106 g) in the semi-humid zone, while the semi-arid zone had a capacity of only 79.4 Mg C ha−1. Soil organic C (SOC) increased continuously with stand age in the semi-arid zone (R2 = 0.84, p = 0.010). However, in the semi-humid zone, SOC declined sharply by 47.8% after the initial stage (5 to 10 y). The C stock in trees increased continuously with stand age in the semi-humid zone (R2 = 0.83, p = 0.011), yet in the semi-arid zone, it decreased dramatically from 43.0 Mg C ha−1 to 28.4 Mg C ha−1 during the old forest stage (38 to 56 y). The shift from being a net C sink to a net C source occurred at the initial stage in the semi-humid zone versus at the old forest stage in the semi-arid zone after reforestation. Surprisingly, with the exception of the initial and later stages (55 y), the patterns of C allocation among trees, soils, understory and litter were not statistically different between the two climate zones. Our results suggest that climate factors can alter the potential amount and age-related dynamics of forest C sequestration. PMID:25799100

Evaluating the potential of reforestation as a mitigative measure for greenhouse gas induced global warming using an energy balance global climate model

NASA Astrophysics Data System (ADS)

Starheim, Fred John

The subject of global warming due to the human addition of greenhouse gases (GHGs) to the atmosphere has been the subject of considerable attention and research in the last two decades. The principal GHG of concern related to human influence is carbon dioxide (CO2). Emissions of this gas have grown rapidly since the industrial revolution in response to the energy and agricultural demands of an increasing world population. Concern exists that the atmospheric concentrations of GHGs may rise sufficiently high so as to impose dangerous interference with the climate system. Numerous methods and measures for the sequestration and avoidance of GHGs have been proposed with the object of decreasing the growth and ultimately stabilizing atmospheric GHG concentrations. The purpose of this work is to examine the effectiveness of one such measure-that of the feasibiltiy of large-scale reforestation/afforestation efforts to mitigate projected global warming. An energy balance global climate model was selected to conduct this work. The model is based on previous work of Pease (1987) in the Annals of the AAG, (77), 450-461, which has been expanded to include dimensions of time and space. The assumed reforestation/afforestation activities are based on a World Resources Institute study by Trexler and Haugen (1995) entitled Keeping it Green Tropical Forest Opportunities for Mitigating Climate Change. The forestry activities are assumed to take place in the tropics where a year-round growing season, plentiful rainfall, and relatively low land development costs should provide the most economically favorable conditions for instituting such a program. The climate model simulations examine the effect of carbon absorption and sequestration in isolation, and then in a subsequent step, examine the combined effect of carbon absorption/sequestration and albedo changes attendant with increased forest cover. Results of the modeling show only small temperature benefits (an approximate 0.1 degree C cooling) associated with implementation of this large-scale reforestation program versus a CO2 doubling case with no forestry programs. Of the approximate 0.1 degree C temperature change, the largest effect was due to CO2 sequestration with the surface albedo effect being negligible (less than 0.01 degree C).

Dynamics of biomass and carbon sequestration across a chronosequence of masson pine plantations

NASA Astrophysics Data System (ADS)

Justine, Meta Francis; Yang, Wanqin; Wu, Fuzhong; Khan, Muhammad Naeem

2017-03-01

The changes of forest biomass stock and carbon (C) sequestration with stand ages at fixed intervals in the different vegetation components remain unknown. Using the masson pine (Pinus massoniana) relative growth equation, biomass carbon stocks were obtained in four masson pine plantations at 12 year intervals (3 years, 15 years, 27 years, and 39 years). Meanwhile, the changes in soil organic C (SOC) stock with stand ages were also estimated. The biomass stock varied from 1.41 to 265.33 Mg ha-1, 6.87 to 7.49 Mg ha-1, and 2.66 to 4.86 Mg ha-1 in the tree, shrub, and herb layers. Carbon concentrations in plant tissues were 51.6%, 39.0%, and 42.2% in the tree, shrub, and herb layers. The aboveground biomass C contributed 81.7% and 60.5% in the tree and shrub layers, and the root to shoot (R/S) ratio of the tree and shrub layer biomass averaged 0.23 and 0.69. Biomass C stock increased significantly (p < 0.05) with forest age, whereas the changes in biomass accumulation rate decreased significantly (p < 0.05). The annual net C sequestration increased with age from 0.47 to 9.83 Mg ha-1 yr-1 in the tree layer but decreased in the shrub and herb layers. The SOC content decreased with soil depth but increased with age, whereas the SOC stock increased with depth and age. However, the total ecosystem C stock increased significantly (p < 0.05) with stand age suggesting that age is the controlling factor of photosynthetic and biological processes and thus changes in biomass accumulation and C sequestration in masson pine plantations. Therefore, in-depth studies are needed for continuous monitoring of the changes in nutrients and elements cycling with stand ages in this forest ecosystem.

Classification of CO2 Geologic Storage: Resource and Capacity

USGS Publications Warehouse

Frailey, S.M.; Finley, R.J.

2009-01-01

The use of the term capacity to describe possible geologic storage implies a realistic or likely volume of CO2 to be sequestered. Poor data quantity and quality may lead to very high uncertainty in the storage estimate. Use of the term "storage resource" alleviates the implied certainty of the term "storage capacity". This is especially important to non- scientists (e.g. policy makers) because "capacity" is commonly used to describe the very specific and more certain quantities such as volume of a gas tank or a hotel's overnight guest limit. Resource is a term used in the classification of oil and gas accumulations to infer lesser certainty in the commercial production of oil and gas. Likewise for CO2 sequestration, a suspected porous and permeable zone can be classified as a resource, but capacity can only be estimated after a well is drilled into the formation and a relatively higher degree of economic and regulatory certainty is established. Storage capacity estimates are lower risk or higher certainty compared to storage resource estimates. In the oil and gas industry, prospective resource and contingent resource are used for estimates with less data and certainty. Oil and gas reserves are classified as Proved and Unproved, and by analogy, capacity can be classified similarly. The highest degree of certainty for an oil or gas accumulation is Proved, Developed Producing (PDP) Reserves. For CO2 sequestration this could be Proved Developed Injecting (PDI) Capacity. A geologic sequestration storage classification system is developed by analogy to that used by the oil and gas industry. When a CO2 sequestration industry emerges, storage resource and capacity estimates will be considered a company asset and consequently regulated by the Securities and Exchange Commission. Additionally, storage accounting and auditing protocols will be required to confirm projected storage estimates and assignment of credits from actual injection. An example illustrates the use of these terms and how storage classification changes as new data become available. ?? 2009 Elsevier Ltd. All rights reserved.

Wind Erosion Caused by Land Use Changes Significantly Reduces Ecosystem Carbon Storage and Carbon Sequestration Potentials in Grassland

NASA Astrophysics Data System (ADS)

Li, P.; Chi, Y. G.; Wang, J.; Liu, L.

2017-12-01

Wind erosion exerts a fundamental influence on the biotic and abiotic processes associated with ecosystem carbon (C) cycle. However, how wind erosion under different land use scenarios will affect ecosystem C balance and its capacity for future C sequestration are poorly quantified. Here, we established an experiment in a temperate steppe in Inner Mongolia, and simulated different intensity of land uses: control, 50% of aboveground vegetation removal (50R), 100% vegetation removal (100R) and tillage (TI). We monitored lateral and vertical carbon flux components and soil characteristics from 2013 to 2016. Our study reveals three key findings relating to the driving factors, the magnitude and consequence of wind erosion on ecosystem C balance: (1) Frequency of heavy wind exerts a fundamental control over the severity of soil erosion, and its interaction with precipitation and vegetation characteristics explained 69% variation in erosion intensity. (2) With increases in land use intensity, the lateral C flux induced by wind erosion increased rapidly, equivalent to 33%, 86%, 111% and 183% of the net ecosystem exchange of the control site under control, 50R, 100R and TI sites, respectively. (3) After three years' treatment, erosion induced decrease in fine fractions led to 31%, 43%, 85% of permanent loss of C sequestration potential in the surface 5cm soil for 50R, 100R and TI sites. Overall, our study demonstrates that lateral C flux associated with wind erosion is too large to be ignored. The loss of C-enriched fine particles not only reduces current ecosystem C content, but also results in irreversible loss of future soil C sequestration potential. The dynamic soil characteristics need be considered when projecting future ecosystem C balance in aeolian landscape. We also propose that to maintain the sustainability of grassland ecosystems, land managers should focus on implementing appropriate land use rather than rely on subsequent managements on degraded soils.

Reimagining Carbon Sequestration in Fluviodeltaic Systems: Contributions from Clastic Overbank Deposits versus Peat

NASA Astrophysics Data System (ADS)

Jankowski, K. L.; Shen, Z.; Tornqvist, T. E.; Steponaitis, E.; Rosenheim, B. E.

2017-12-01

Understanding how natural systems sequester carbon, and at what rates, is critical for planning future climate change mitigation strategies. For the decade from 2006-2015, average annual CO2 emissions to the atmosphere ( 11 Pg C) are not completely offset by atmospheric retention and oceanic uptake ( 5 Pg C and 2.5 Pg C, respectively) (LeQuéré et al., 2016) implying residual terrestrial C sinks that are not fully understood. Rivers are increasingly recognized as playing a complex role in the global C cycle which, beyond acting as a source of CO2to the atmosphere, may act as a C sink. Here, we find that the mechanisms of C transfer through fluviodeltaic systems include various means of C storage and contribute significantly to the global unidentified terrestrial C sink. C sequestration by coastal wetlands - at a globally averaged rate of 200 g C/m2/yr - has been widely recognized as an important mechanism for terrestrial C sequestration, with less attention paid to the role of inland fluvial to deltaic deposition. We sampled three cores in the central Mississippi Delta for C content (using elemental analysis) and bulk density in fluviodeltaic overbank deposits as well as intercalated peat. We also established a flexible, Bayesian age-depth model using Bacon (Blaauw and Christen 2011) in order to calculate sediment accumulation rates from 14C and OSL ages. Peat deposits sequester C at an average rate of 40 g C/m2/yr. The relatively organic-poor overbank sediments sequester C at an average rate of 200 g C/m2/yr including what are likely punctuated periods of very fast deposition. While the episodic nature of overbank deposits make quantifying an annual impact difficult, it is clear that overbank deposition is an important and efficient mechanism for C sequestration in fluviodeltaic systems that deserves continued investigation.

Spatially explicit assessment of ecosystem services in China's Loess Plateau: Patterns, interactions, drivers, and implications

NASA Astrophysics Data System (ADS)

Jiang, Chong; Zhang, Haiyan; Zhang, Zhidong

2018-02-01

Human demands for natural resources have significantly changed the natural landscape and induced ecological degradation and associated ecosystem services. An understanding of the patterns, interactions, and drivers of ecosystem services is essential for the ecosystem management and guiding targeted land use policy-making. The Losses Plateau (LP) provides ecosystem services including the carbon sequestration and soil retention, and exerts tremendous impacts on the midstream and downstream of the Yellow River. Three dominant ecosystem services between 2000 and 2012 within the LP were presented based on multiple source datasets and biophysical models. In addition, paired ecosystem services interactions were quantified using the correlation analysis and constraint line approach. The main conclusions are as follows. It was observed that the warming and wetting climate and ecological program jointly promoted the vegetation growth and carbon sequestration. The increasing precipitation throughout 2000-2012 was related to the soil retention and hydrological regulation fluctuations. The vegetation restoration played a positive role in the soil retention enhancement, thus substantially reduced water and sediment yields. The relationships between ecosystem services were not only correlations (tradeoffs or synergies), but rather constraint effects. The constraint effects between the three paired ecosystem services could be classified as the negative convex (carbon sequestration vs. hydrological regulation) and hump-shaped (soil retention vs. carbon sequestration and soil retention vs. hydrological regulation), and the coefficients of determination for the entire LP were 0.78, 0.84, and 0.65, respectively. In the LP, the rainfall (water availability) was the key constraint factor that affected the relationships between the paired ecosystem services. The spatially explicit mapping of ecosystem services and interaction analyses utilizing constraint line approach enriched the understanding of connections between ecosystem services and the potential drivers, which had important implications for the land use planning and landscapes services optimizing.

Attitudinal and Motivational Variables Related to Mathematics Achievement in Jordan: Findings from the Third International Mathematics and Science Study (TIMSS)

ERIC Educational Resources Information Center

Hammouri, Hind

2004-01-01

The purpose of the present study was to examine the effects of student-related variables on achievement in mathematics. The sample consisted of 3736 13-year-old Jordanian 8th-graders who participated in the Third International Mathematics and Science Study (TIMSS). The participants completed a student questionnaire and participated in the…

Peirce's Philosophy of Mathematical Education: Fostering Reasoning Abilities for Mathematical Inquiry

ERIC Educational Resources Information Center

Campos, Daniel G.

2010-01-01

I articulate Charles S. Peirce's philosophy of mathematical education as related to his conception of mathematics, the nature of its method of inquiry, and especially, the reasoning abilities required for mathematical inquiry. The main thesis is that Peirce's philosophy of mathematical education primarily aims at fostering the development of the…

African American Mathematics Teachers as Agents in Their African American Students' Mathematics Identity Formation

ERIC Educational Resources Information Center

Clark, Lawrence M.; Badertscher, Eden M.; Napp, Carolina

2013-01-01

Background/Context: Recent research in mathematics education has employed sociocultural and historical lenses to better understand how students experience school mathematics and come to see themselves as capable mathematics learners. This work has identified mathematics classrooms as places where power struggles related to students'…

Mathematical Modeling in Mathematics Education: Basic Concepts and Approaches

ERIC Educational Resources Information Center

Erbas, Ayhan Kürsat; Kertil, Mahmut; Çetinkaya, Bülent; Çakiroglu, Erdinç; Alacaci, Cengiz; Bas, Sinem

2014-01-01

Mathematical modeling and its role in mathematics education have been receiving increasing attention in Turkey, as in many other countries. The growing body of literature on this topic reveals a variety of approaches to mathematical modeling and related concepts, along with differing perspectives on the use of mathematical modeling in teaching and…

Elementary Pre-Service Teachers' Mathematics Anxiety and Mathematics Teaching Anxiety

ERIC Educational Resources Information Center

Haciomeroglu, Guney

2014-01-01

The present study examined the structure of elementary pre-service teachers' mathematics anxiety and mathematics teaching anxiety by asking whether the two systems of anxiety are related. The Turkish Mathematics Anxiety Rating Scale Short Version and the Mathematics Teaching Anxiety Scale were administered to 260 elementary pre-service teachers.…

Teaching Mathematical Modeling in Mathematics Education

ERIC Educational Resources Information Center

Saxena, Ritu; Shrivastava, Keerty; Bhardwaj, Ramakant

2016-01-01

Mathematics is not only a subject but it is also a language consisting of many different symbols and relations. Taught as a compulsory subject up the 10th class, students are then able to choose whether or not to study mathematics as a main subject. The present paper discusses mathematical modeling in mathematics education. The article provides…

Adolescents' perceptions of socializers' beliefs, career-related conversations, and motivation in mathematics.

PubMed

Lazarides, Rebecca; Rubach, Charlott; Ittel, Angela

2017-03-01

Research based on the Eccles model of parent socialization demonstrated that parents are an important source of value and ability information for their children. Little is known, however, about the bidirectional effects between students' perceptions of their parents' beliefs and behaviors and the students' own domain-specific values. This study analyzed how students' perceptions of parents' beliefs and behaviors and students' mathematics values and mathematics-related career plans affect each other bidirectionally, and analyzed the role of students' gender as a moderator of these relations. Data from 475 students in 11th and 12th grade (girls: 50.3%; 31 classrooms; 12 schools), who participated in 2 waves of the study, were analyzed. Results of longitudinal structural equation models demonstrated that students' perceptions of their parents' mathematics value beliefs at Time 1 affected the students' own mathematics utility value at Time 2. Bidirectional effects were not shown in the full sample but were identified for boys. The paths within the tested model varied for boys and girls. For example, boys', not girls', mathematics intrinsic value predicted their reported conversations with their fathers about future occupational plans. Boys', not girls', perceived parents' mathematics value predicted the mathematics utility value. Findings are discussed in relation to their implications for parents and teachers, as well as in relation to gendered motivational processes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Protein Sequestration of Lipophilic Furanocoumarins in Grapefruit Juice

USDA-ARS?s Scientific Manuscript database

Our previous discoveries of grapefruit furanocoumarin binding to edible fungi led us to investigate the possible roles of dietary factors in this binding phenomenon. In this present study sequestration of grapefruit furanocoumarins by foods was investigated by characterizing the binding between thes...

Gymnomyces xerophilus sp. nov. (sequestrate Russulaceae), an ectomycorrhizal associate of Quercus in California.

Treesearch

Matthew E. Smith; James M. Trappe; David M. Rizzo; Steven L. Miller

2006-01-01

Gymnomyces xerophilus sp. nov., a sequestrate species in the Russulaceae, is characterized and described morphologically as a new species from Quercus-dominated woodlands in California. ITS sequences recovered from healthy, ectomycorrhizal roots of Quercus douglasii and Q....

The nuts and bolts of carbon sequestration in forests

EPA Science Inventory

The nature of carbon in forests is discussed from the perspective of carbon trading as an incentive for conserving private forest lands. The presentation addresses carbon sequestration in forests and its significance for global warming. Carbon inventories, specifically in the are...

Sequestration of mitochondrial iron by silica particles initiates a biological effect.

EPA Science Inventory

Summary Inhalation of particulate matter has presented a challenge to human health for thousands of years. The underlying mechanism for biological effect following particle exposure is incompletely understood. We tested the postulate that particle sequestration of cell and mit...

Biochar: A synthesis of its agronomic impact beyond carbon sequestration

USDA-ARS?s Scientific Manuscript database

Biochar has been recently heralded as an amendment to revitalize degraded soils, improve soil carbon sequestration, increase agronomic productivity and enter into future carbon trading markets. However, scientific and economic technicalities may limit the ability of biochar to consistently deliver o...

The role of initial affective impressions in responses to educational communications: the case of carbon capture and sequestration (CCS).

PubMed

Bruine de Bruin, Wändi; Wong-Parodi, Gabrielle

2014-06-01

Emerging technologies promise potential benefits at a potential cost. Developers of educational communications aim to improve people's understanding and to facilitate public debate. However, even relatively uninformed recipients may have initial feelings that are difficult to change. We report that people's initial affective impressions about carbon capture and sequestration (CCS), a low-carbon coal-based electricity-generation technology with which most people are unfamiliar, influences how they interpret previously validated education materials. As a result, even individuals who had originally self-identified as uninformed persisted in their initial feelings after reading the educational communication-though perseverance of feelings about CCS was stronger among recipients who had originally self-identified as relatively informed (Study 1). Moreover, uninformed recipients whose initial feelings were experimentally manipulated by relatively uninformative pro-CCS or anti-CCS arguments persisted in their manipulated feelings after reading the educational communication, due to evaluating the educational communication in line with their manipulated impressions (Study 2). Hence, our results suggest that educational communications will have more impact if they are disseminated before people form strong feelings about the topic under consideration, especially if these are based on little to no factual understanding. PsycINFO Database Record (c) 2014 APA, all rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Soltanian, Mohamad Reza; Amooie, Mohammad Amin; Cole, David R.

In this study, a field-scale carbon dioxide (CO 2) injection pilot project was conducted as part of the Southeast Regional Sequestration Partnership (SECARB) at Cranfield, Mississippi. We present higher-order finite element simulations of the compositional two-phase CO 2-brine flow and transport during the experiment. High- resolution static models of the formation geology in the Detailed Area Study (DAS) located below the oil- water contact (brine saturated) are used to capture the impact of connected flow paths on breakthrough times in two observation wells. Phase behavior is described by the cubic-plus-association (CPA) equation of state, which takes into account the polarmore » nature of water molecules. Parameter studies are performed to investigate the importance of Fickian diffusion, permeability heterogeneity, relative permeabilities, and capillarity. Simulation results for the pressure response in the injection well and the CO 2 breakthrough times at the observation wells show good agreement with the field data. For the high injection rates and short duration of the experiment, diffusion is relatively unimportant (high P clet numbers), while relative permeabilities have a profound impact on the pressure response. High-permeability pathways, created by fluvial deposits, strongly affect the CO 2 transport and highlight the importance of properly characterizing the formation heterogeneity in future carbon sequestration projects.« less

The contribution of executive functions to emergent mathematic skills in preschool children.

PubMed

Espy, Kimberly Andrews; McDiarmid, Melanie M; Cwik, Mary F; Stalets, Melissa Meade; Hamby, Arlena; Senn, Theresa E

2004-01-01

Mathematical ability is related to both activation of the prefrontal cortex in neuroimaging studies of adults and to executive functions in school-age children. The purpose of this study was to determine whether executive functions were related to emergent mathematical proficiency in preschool children. Preschool children (N = 96) were administered an executive function battery that was reduced empirically to working memory (WM), inhibitory control (IC), and shifting abilities by calculating composite scores derived from principal component analysis. Both WM and IC predicted early arithmetic competency, with the observed relations robust after controlling statistically for child age, maternal education, and child vocabulary. Only IC accounted for unique variance in mathematical skills, after the contribution of other executive functions were controlled statistically as well. Specific executive functions are related to emergent mathematical proficiency in this age range. Longitudinal studies using structural equation modeling are necessary to better characterize these ontogenetic relations.

Negative Emissions Technology

NASA Astrophysics Data System (ADS)

Day, Danny

2006-04-01

Although `negative emissions' of carbon dioxide need not, in principle, involve use of biological processes to draw carbon out of the atmosphere, such `agricultural' sequestration' is the only known way to remove carbon from the atmosphere on time scales comparable to the time scale for anthropogenic increases in carbon emissions. In order to maintain the `negative emissions' the biomass must be used in such a way that the resulting carbon dioxide is separated and permanently sequestered. Two options for sequestration are in the topsoil and via geologic carbon sequestration. The former has multiple benefits, but the latter also is needed. Thus, although geologic carbon sequestration is viewed skeptically by some environmentalists as simply a way to keep using fossil fuels---it may be a key part of reversing accelerating climate forcing if rapid climate change is beginning to occur. I will first review the general approach of agricultural sequestration combined with use of resulting biofuels in a way that permits carbon separation and then geologic sequestration as a negative emissions technology. Then I discuss the process that is the focus of my company---the EPRIDA cycle. If deployed at a sufficiently large scale, it could reverse the increase in CO2 concentrations. I also estimate of benefits --carbon and other---of large scale deployment of negative emissions technologies. For example, using the EPRIDA cycle by planting and soil sequestering carbon in an area abut In 3X the size of Texas would remove the amount of carbon that is being accumulated worldwide each year. In addition to the atmospheric carbon removal, the EPRIDA approach also counters the depletion of carbon in the soil---increasing topsoil and its fertility; reduces the excess nitrogen in the water by eliminating the need for ammonium nitrate fertilizer and reduces fossil fuel reliance by providing biofuel and avoiding natural gas based fertilizer production.

An Evaluation of Subsurface Microbial Activity Conditional to Subsurface Temperature, Porosity, and Permeability at North American Carbon Sequestration Sites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilson, B.; Mordensky, S.; Verba, Circe

Several nations, including the United States, recognize global climate change as a force transforming the global ecosphere. Carbon dioxide (CO 2) is a greenhouse gas that contributes to the evolving climate. Reduction of atmospheric CO 2 levels is a goal for many nations and carbon sequestration which traps CO 2 in the Earth’s subsurface is one method to reduce atmospheric CO 2 levels. Among the variables that must be considered in developing this technology to a national scale is microbial activity. Microbial activity or biomass can change rock permeability, alter artificial seals around boreholes, and play a key role inmore » biogeochemistry and accordingly may determine how CO 2 is sequestered underground. Certain physical parameters of a reservoir found in literature (e.g., temperature, porosity, and permeability) may indicate whether a reservoir can host microbial communities. In order to estimate which subsurface formations may host microbes, this report examines the subsurface temperature, porosity, and permeability of underground rock formations that have high potential to be targeted for CO 2 sequestration. Of the 268 North American wellbore locations from the National Carbon Sequestration Database (NATCARB; National Energy and Technology Laboratory, 2015) and 35 sites from Nelson and Kibler (2003), 96 sequestration sites contain temperature data. Of these 96 sites, 36 sites have temperatures that would be favorable for microbial survival, 48 sites have mixed conditions for supporting microbial populations, and 11 sites would appear to be unfavorable to support microbial populations. Future studies of microbe viability would benefit from a larger database with more formation parameters (e.g. mineralogy, structure, and groundwater chemistry), which would help to increase understanding of where CO 2 sequestration could be most efficiently implemented.« less

Research and Development of a DNDC Online Model for Farmland Carbon Sequestration and GHG Emissions Mitigation in China.

PubMed

Jiang, Zaidi; Yin, Shan; Zhang, Xianxian; Li, Changsheng; Shen, Guangrong; Zhou, Pei; Liu, Chunjiang

2017-12-01

Appropriate agricultural practices for carbon sequestration and emission mitigation have a significant influence on global climate change. However, various agricultural practices on farmland carbon sequestration usually have a major impact on greenhouse gas (GHG) emissions. It is very important to accurately quantify the effect of agricultural practices. This study developed a platform-the Denitrification Decomposition (DNDC) online model-for simulating and evaluating the agricultural carbon sequestration and emission mitigation based on the scientific process of the DNDC model, which is widely used in the simulation of soil carbon and nitrogen dynamics. After testing the adaptability of the platform on two sampling fields, it turned out that the simulated values matched the measured values well for crop yields and GHG emissions. We used the platform to estimate the effect of three carbon sequestration practices in a sampling field: nitrogen fertilization reduction, straw residue and midseason drainage. The results indicated the following: (1) moderate decrement of the nitrogen fertilization in the sampling field was able to decrease the N₂O emission while maintaining the paddy rice yield; (2) ground straw residue had almost no influence on paddy rice yield, but the CH₄ emission and the surface SOC concentration increased along with the quantity of the straw residue; (3) compared to continuous flooding, midseason drainage would not decrease the paddy rice yield and could lead to a drop in CH₄ emission. Thus, this study established the DNDC online model, which is able to serve as a reference and support for the study and evaluation of the effects of agricultural practices on agricultural carbon sequestration and GHG emissions mitigation in China.

Assessing Potential Future Carbon Dynamics with Climate Change and Fire Management in a Mountainous Landscape on the Olympic Peninsula, Washington, USA

NASA Astrophysics Data System (ADS)

Kennedy, R. S.

2010-12-01

Forests of the mountainous landscapes of the maritime Pacific Northwestern USA may have high carbon sequestration potential via their high productivity and moderate to infrequent fire regimes. With climate change, there may be shifts in incidence and severity of fire, especially in the drier areas of the region, via changes to forest productivity and hydrology, and consequent effects to C sequestration and forest structure. To explore this issue, I assessed potential effects of fire management (little fire suppression/wildland fire management/highly effective fire suppression) under two climate change scenarios on future C sequestration dynamics (amounts and spatial pattern) in Olympic National Park, WA, over a 500-year simulation period. I used the simulation platform FireBGCv2, which contains a mechanistic, individual tree succession model, a spatially explicit climate-based biophysical model that uses daily weather data, and a spatially explicit fire model incorporating ignition, spread, and effects on ecosystem components. C sequestration patterns varied over time and spatial and temporal patterns differed somewhat depending on the climate change scenario applied and the fire management methods employed. Under the more extreme climate change scenario with little fire suppression, fires were most frequent and severe and C sequestration decreased. General trends were similar under the more moderate climate change scenario, as compared to current climate, but spatial patterns differed. Both climate change scenarios under highly effective fire suppression showed about 50% of starting total C after the initial transition phase, whereas with 10% fire suppression both scenarios exhibited about 10% of starting amounts. Areas of the landscape that served as refugia for older forest under increasing frequency of high severity fire were also hotspots for C sequestration in a landscape experiencing increasing frequency of disturbance with climate change.

Twenty Years Later: High School Students Who Showed Promise in Mathematics.

ERIC Educational Resources Information Center

Turner, Nura D.

1981-01-01

Data from longitudinal studies of high school students who took the Annual High School Mathematics Examination sponsored by the Mathematical Association of America (MAA) indicate that 56 percent of the top achievers pursued careers in mathematics or mathematically related fields. (MP)

Carbon sequestration potential for forage and pasture systems

USDA-ARS?s Scientific Manuscript database

Grassland soils represent a large reservoir of organic and inorganic carbon. Regionally, grasslands are annual CO2 sources or sinks depending on crop and soil management, current soil organic carbon (SOC) concentration and climate. Land management changes (LMC) impact SOC sequestration rate, the du...

The systemic pathology of cerebral malaria in African children

PubMed Central

Milner, Danny A.; Whitten, Richard O.; Kamiza, Steve; Carr, Richard; Liomba, George; Dzamalala, Charles; Seydel, Karl B.; Molyneux, Malcolm E.; Taylor, Terrie E.

2014-01-01

Pediatric cerebral malaria carries a high mortality rate in sub-Saharan Africa. We present our systematic analysis of the descriptive and quantitative histopathology of all organs sampled from a series of 103 autopsies performed between 1996 and 2010 in Blantyre, Malawi on pediatric cerebral malaria patients and control patients (without coma, or without malaria infection) who were clinically well characterized prior to death. We found brain swelling in all cerebral malaria patients and the majority of controls. The histopathology in patients with sequestration of parasites in the brain demonstrated two patterns: (a) the “classic” appearance (i.e., ring hemorrhages, dense sequestration, and extra-erythrocytic pigment) which was associated with evidence of systemic activation of coagulation and (b) the “sequestration only” appearance associated with shorter duration of illness and higher total burden of parasites in all organs including the spleen. Sequestration of parasites was most intense in the gastrointestinal tract in all parasitemic patients (those with cerebral malarial and those without). PMID:25191643

Community perceptions of carbon sequestration: insights from California

NASA Astrophysics Data System (ADS)

Wong-Parodi, Gabrielle; Ray, Isha

2009-07-01

Over the last decade, many energy experts have supported carbon sequestration as a viable technological response to climate change. Given the potential importance of sequestration in US energy policy, what might explain the views of communities that may be directly impacted by the siting of this technology? To answer this question, we conducted focus groups in two communities who were potentially pilot project sites for California's DOE-funded West Coast Regional Partnership (WESTCARB). We find that communities want a voice in defining the risks to be mitigated as well as the justice of the procedures by which the technology is implemented. We argue that a community's sense of empowerment is key to understanding its range of carbon sequestration opinions, where 'empowerment' includes the ability to mitigate community-defined risks of the technology. This sense of empowerment protects the community against the downside risk of government or corporate neglect, a risk that is rarely identified in risk assessments but that should be factored into assessment and communication strategies.

The effect of ocean acidification on carbon storage and sequestration in seagrass beds; a global and UK context.

PubMed

Garrard, Samantha L; Beaumont, Nicola J

2014-09-15

Ocean acidification will have many negative consequences for marine organisms and ecosystems, leading to a decline in many ecosystem services provided by the marine environment. This study reviews the effect of ocean acidification (OA) on seagrasses, assessing how this may affect their capacity to sequester carbon in the future and providing an economic valuation of these changes. If ocean acidification leads to a significant increase in above- and below-ground biomass, the capacity of seagrass to sequester carbon will be significantly increased. The associated value of this increase in sequestration capacity is approximately £500 and 600 billion globally between 2010 and 2100. A proportionally similar increase in carbon sequestration value was found for the UK. This study highlights one of the few positive stories for ocean acidification and underlines that sustainable management of seagrasses is critical to avoid their continued degradation and loss of carbon sequestration capacity. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Effect of Emissions Trading And Carbon Sequestration on The Cost Of CO2 Emissions Mitigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahasenan, Natesan; Scott, Michael J.; Smith, Steven J.

2002-08-05

The deployment of carbon capture and sequestration (CC&S) technologies is greatly affected by the marginal cost of controlling carbon emissions (also the value of carbon, when emissions permits are traded). Emissions limits that are more stringent in the near term imply higher near-term carbon values and therefore encourage the local development and deployment of CC&S technologies. In addition, trade in emissions obligations lowers the cost of meeting any regional or global emissions limit and so affects the rate of penetration of CC&S technologies. We examine the effects of the availability of sequestration opportunities and emissions trading (either within select regionsmore » or globally) on the cost of emissions mitigation and compliance with different emissions reduction targets for the IPCC SRES scenarios. For each base scenario and emissions target, we examine the issues outlined above and present quantitative estimates for the impacts of trade and the availability of sequestration opportunities in meeting emissions limitation obligations.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarmiento, Jorge L.; Chavez, Francisco; Maltrud, Matthew

The purpose of this proposal was to fund a workshop to bring together the principal investigators of all the projects that were being funded under the DOE ocean carbon sequestration research program. The primary goal of the workshop was to interchange research results, to discuss ongoing research, and to identify future research priorities. In addition, we hoped to encourage the development of synergies and collaborations between the projects and to write an EOS article summarizing the results of the meeting. Appendix A summarizes the plan of the workshop as originally proposed, Appendix B lists all the principal investigators who weremore » able to attend the workshop, Appendix C shows the meeting agenda, and Appendix D lists all the abstracts that were provided prior to the meeting. The primary outcome of the meeting was a decision to write two papers for the reviewed literature on carbon sequestration by iron fertilization, and on carbon sequestration by deep sea injection and to examine the possibility of an overview article in EOS on the topic of ocean carbon sequestration.« less

Girls, Moms, and Math: A Study of the Relationship of Self and Maternal Attitudes towards Mathematics and Girls' Mathematical Success in an Affluent Suburban Community

ERIC Educational Resources Information Center

DeRosa, Ann T.

2011-01-01

This study focused on gender-based mathematics performance. It was a qualitative study of girls and their mothers conducted to identify variables that may to be associated with the success or lack of success of the girls. By examining maternal responses to mathematics-related questions, themes emerged that could be related to information gathered…

Is There a Relationship between Pre-Service Teachers' Mathematical Values and Their Teaching Anxiety in Mathematics?

ERIC Educational Resources Information Center

Yazici, Ersen; Peker, Murat; Ertekin, Erhan; Dilmac, Bulent

2011-01-01

Introduction: The aim of this study is to investigate the relation between the pre-service teachers' mathematical values and teaching anxieties in mathematics. Method: The research was carried out on 359 teacher candidates attending the elementary school mathematics, secondary school mathematics and primary school teaching programs. To this end,…

A Structural Analysis on Korean Young Children's Mathematical Ability and Its Related Children's and Mothers' Variables

ERIC Educational Resources Information Center

Lee, Hye Jung; Kim, Jihyun

2016-01-01

The objective of this study is to examine the structural relationships among variables that predict the mathematical ability of young children, namely young children's mathematical attitude, exposure to private mathematical learning, mothers' view about their children's mathematical learning, and mothers' mathematical attitude. To this end, we…

From Searle's Chinese Room to the Mathematics Classroom: Technical and Cognitive Mathematics

ERIC Educational Resources Information Center

Gavalas, Dimitris

2007-01-01

Employing Searle's views, I begin by arguing that students of Mathematics behave similarly to machines that manage symbols using a set of rules. I then consider two types of Mathematics, which I call "Cognitive Mathematics" and "Technical Mathematics" respectively. The former type relates to concepts and meanings, logic and sense, whilst the…

Mathematical Knowledge for Teaching, Standards-Based Mathematics Teaching Practices, and Student Achievement in the Context of the "Responsive Classroom Approach"

ERIC Educational Resources Information Center

Ottmar, Erin R.; Rimm-Kaufman, Sara E.; Larsen, Ross A.; Berry, Robert Q.

2015-01-01

This study investigates the effectiveness of the Responsive Classroom (RC) approach, a social and emotional learning intervention, on changing the relations between mathematics teacher and classroom inputs (mathematical knowledge for teaching [MKT] and standards-based mathematics teaching practices) and student mathematics achievement. Work was…

Achievement of Eighth-Grade Students in Korea on the TIMSS 2011 Assessment: Effects of Confidence in Mathematics and Engagement in Mathematics Lessons

ERIC Educational Resources Information Center

House, J. Daniel; Telese, James A.

2016-01-01

Research studies have identified several factors related to mathematics achievement of students in Korea. Further, results from the Trends in International Mathematics and Science Study (TIMSS) assessments have shown that instructional practices and beliefs about mathematics were significantly associated with mathematics achievement of students in…

Relations between Mathematical Knowledge for Teaching, Mathematics Instructional Quality, and Student Achievement in the Context of the "Responsive Classroom (RC)" Approach

ERIC Educational Resources Information Center

Ottmar, Erin R.; Rimm-Kaufman, Sara E.; Larsen, Ross; Merritt, Eileen G.

2011-01-01

Despite over thirty years of theoretically based research investigating "how" teacher mathematical knowledge and instructional practice relate to student learning, it is still largely unclear how these constructs are related, and policy makers and practitioners are still situated in a context with insufficient data to make decisions. Thus, there…

Micrometeorological Technique for Monitoring of Geological Carbon Capture, Utilization and Storage: Methodology, Workflow and Resources

NASA Astrophysics Data System (ADS)

Burba, G. G.; Madsen, R.; Feese, K.

2013-12-01

The eddy covariance (EC) method is a micrometeorological technique for direct high-speed measurements of the transport of gases and energy between land or water surfaces and the atmosphere [1]. This method allows for observations of gas transport scales from 20-40 times per second to multiple years, represents gas exchange integrated over a large area, from hundreds of square meters to tens of square kilometres, and corresponds to gas exchange from the entire surface, including canopy, and soil or water layers. Gas fluxes, emission and exchange rates are characterized from single-point in situ measurements using permanent or mobile towers, or moving platforms such as automobiles, helicopters, airplanes, etc. Presently, over 600 eddy covariance stations are in operation in over 120 countries [1]. EC is now recognized as an effective method in regulatory and industrial applications, including CCUS [2-10]. Emerging projects utilize EC to continuously monitor large areas before and after the injections, to locate and quantify leakages where CO2 may escape from the subsurface, to improve storage efficiency, and for other CCUS characterizations [5-10]. Although EC is one of the most direct and defensible micrometeorological techniques measuring gas emission and transport, and complete automated stations and processing are readily available, the method is mathematically complex, and requires careful setup and execution specific to the site and project. With this in mind, step-by-step instructions were created in [1] to introduce a novice to the EC method, and to assist in further understanding of the method through more advanced references. In this presentation we provide brief highlights of the eddy covariance method, its application to geological carbon capture, utilization and storage, key requirements, instrumentation and software, and review educational resources particularly useful for carbon sequestration research. References: [1] Burba G. Eddy Covariance Method for Scientific, Industrial, Agricultural and Regulatory Applications. LI-COR Biosciences; 2013. [2] International Energy Agency. Quantification techniques for CO2 leakage. IEA-GHG; 2012. [3] US Department of Energy. Best Practices for Monitoring, Verification, and Accounting of CO2 Stored in Deep Geologic Formations. US DOE; 2012. [4] Liu G. (Ed.). Greenhouse Gases: Capturing, Utilization and Reduction. Intech; 2012. [5] Finley R. et al. An Assessment of Geological Carbon Sequestration Options in the Illinois Basin - Phase III. DOE-MGSC; DE-FC26-05NT42588; 2012. [6] LI-COR Biosciences. Surface Monitoring for Geologic Carbon Sequestration. LI-COR, 980-11916, 2011. [7] Lewicki J., Hilley G. Eddy covariance mapping and quantification of surface CO2 leakage fluxes. GRL, 2009; 36: L21802. [8] Finley R. An Assessment of Geological Carbon Sequestration in the Illinois Basin. Overview of the Decatur-Illinois Basin Site. DOE-MGSC; 2009. [9] Eggleston H., et al. (Eds). IPCC Guidelines for National Greenhouse Gas Inventories, IPCC NGGI P, WMO/UNEP; 2006-2011. [10] Burba G., Madsen R., Feese K. Eddy Covariance Method for CO2 Emission Measurements in CCUS Applications: Principles, Instrumentation and Software. Energy Procedia; Submitted: 1-8.

Wind erosion reduces soil organic carbon sequestration falsely indicating ineffective management practices

NASA Astrophysics Data System (ADS)

Chappell, Adrian; Baldock, Jeffrey A.

2016-09-01

Improved management of agricultural land has the potential to reduce greenhouse gas emissions and to reduce atmospheric CO2 via soil carbon sequestration. However, SOC stocks are reduced by soil erosion which is commonly omitted from calculations of crop production, C cycling, C sequestration and C accounting. We used fields from the wind eroded dryland cropping region of Western Australia to demonstrate the global implications for C sequestration and C accounting of omitting soil erosion. For the fields we previously estimated mean net (1950s-1990) soil erosion of 1.2 ± 1.0 t ha-1 y-1. The mean net (1990-2013) soil erosion increased by nearly four times to 4.4 ± 2.1 t ha-1 y-1. Conservation agriculture has evidently not reduced wind erosion in this region. The mean net (1990-2013) SOC erosion was up to 0.2 t C ha-1 y-1 across all sampled fields and similar to measured sequestration rates in the region (up to 0.5 t C ha-1 y-1; 10 years) for many management practices recommended for building SOC stocks. The minimum detectable change (MDC; 10 years) of SOC without erosion was up to 0.2 t C ha-1 y-1 whilst the MDC of SOC with erosion was up to 0.4 t C ha-1 y-1. These results illustrate the generally applicable outcome: (i) if SOC erosion is equal to (or greater than) the increase in SOC due to management practices, the change will not be detectable (or a loss will be evident); (ii) without including soil erosion in SOC sequestration calculations, the monitoring of SOC stocks will lead to, at best the inability to detect change and, at worst the false impression that management practices have failed to store SOC. Furthermore, continued omission of soil erosion in crop production, C accounting and C sequestration will most likely undermine confidence in policy designed to encourage adoption of C farming and the attendant benefits for soil stewardship and food security.

Soil carbon sequestration potential of permanent pasture and continuous cropping soils in New Zealand.

PubMed

McNally, Sam R; Beare, Mike H; Curtin, Denis; Meenken, Esther D; Kelliher, Francis M; Calvelo Pereira, Roberto; Shen, Qinhua; Baldock, Jeff

2017-11-01

Understanding soil organic carbon (SOC) sequestration is important to develop strategies to increase the SOC stock and, thereby, offset some of the increases in atmospheric carbon dioxide. Although the capacity of soils to store SOC in a stable form is commonly attributed to the fine (clay + fine silt) fraction, the properties of the fine fraction that determine the SOC stabilization capacity are poorly known. The aim of this study was to develop an improved model to estimate the SOC stabilization capacity of Allophanic (Andisols) and non-Allophanic topsoils (0-15 cm) and, as a case study, to apply the model to predict the sequestration potential of pastoral soils across New Zealand. A quantile (90th) regression model, based on the specific surface area and extractable aluminium (pyrophosphate) content of soils, provided the best prediction of the upper limit of fine fraction carbon (FFC) (i.e. the stabilization capacity), but with different coefficients for Allophanic and non-Allophanic soils. The carbon (C) saturation deficit was estimated as the difference between the stabilization capacity of individual soils and their current C concentration. For long-term pastures, the mean saturation deficit of Allophanic soils (20.3 mg C g -1 ) was greater than that of non-Allophanic soils (16.3 mg C g -1 ). The saturation deficit of cropped soils was 1.14-1.89 times that of pasture soils. The sequestration potential of pasture soils ranged from 10 t C ha -1 (Ultic soils) to 42 t C ha -1 (Melanic soils). Although meeting the estimated national soil C sequestration potential (124 Mt C) is unrealistic, improved management practices targeted to those soils with the greatest sequestration potential could contribute significantly to off-setting New Zealand's greenhouse gas emissions. As the first national-scale estimate of SOC sequestration potential that encompasses both Allophanic and non-Allophanic soils, this serves as an informative case study for the international community. © 2017 John Wiley & Sons Ltd.

Ecological carbon sequestration via wood harvest and storage (WHS): Can it be a viable climate and energy strategy?

NASA Astrophysics Data System (ADS)

Zeng, N.; Zaitchik, B. F.; King, A. W.; Wullschleger, S. D.

2016-12-01

A carbon sequestration strategy is proposed in which forests are sustainably managed to optimal carbon productivity, and a fraction of the wood is selectively harvested and stored to prevent decomposition under anaerobic, dry or cold conditions. Because a large flux of CO2 is constantly assimilated into the world's forests via photosynthesis, cutting off its return pathway to the atmosphere forms an effective carbon sink. The live trees serve as a `carbon scrubber' or `carbon remover' that provides continuous sequestration (negative emissions). The stored wood is a semi-permanent carbon sink, but also serves as a `biomass/bioenergy reserve' that could be utilized in the future.Based on forest coarse wood production rate, land availability, bioconservation and other practical constraints, we estimate a carbon sequestration potential for wood harvest and storage (WHS) 1-3 GtC y-1. The implementation of such a scheme at our estimated lower value of 1 GtC y-1 would imply a doubling of the current world wood harvest rate. This can be achieved by harvesting wood at a modest harvesting intensity of 1.2 tC ha-1 y-1, over a forest area of 8 Mkm2 (800 Mha). To achieve the higher value of 3 GtC y-1, forests need to be managed this way on half of the world's forested land, or on a smaller area but with higher harvest intensity. However, the actual implementation may face challenges that vary regionally. We propose `carbon sequestration and biomass farms' in the tropical deforestation frontiers with mixed land use for carbon, energy, agriculture, as well as conservation. In another example, the forests damaged by insect infestation could be thinned to reduce fire and harvested for carbon sequestration.We estimate a cost of $10-50/tCO2 for harvest and storage around the landing site. The technique is low tech, distributed and reversible. We compare the potential of WHS with a number of other carbon sequestration methods. We will also show its impact on future land carbon sink and climate target using carbon-cliamte model projections.

BIG SKY CARBON SEQUESTRATION PARTNERSHIP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Susan M. Capalbo

2004-10-31

The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership fall into four areas: evaluation of sources and carbon sequestration sinks; development of GIS-based reporting framework; designing an integrated suite of monitoring, measuring, and verification technologies; and initiating a comprehensive education and outreach program. At the first two Partnership meetings the groundwork was put in place to provide an assessment of capture and storage capabilities for CO{sub 2} utilizing the resources foundmore » in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. During the third quarter, planning efforts are underway for the next Partnership meeting which will showcase the architecture of the GIS framework and initial results for sources and sinks, discuss the methods and analysis underway for assessing geological and terrestrial sequestration potentials. The meeting will conclude with an ASME workshop. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other western DOE partnerships. Efforts are also being made to find funding to include Wyoming in the coverage areas for both geological and terrestrial sinks and sources. The Partnership recognizes the critical importance of measurement, monitoring, and verification technologies to support not only carbon trading but all policies and programs that DOE and other agencies may want to pursue in support of GHG mitigation. The efforts begun in developing and implementing MMV technologies for geological sequestration reflect this concern. Research is also underway to identify and validate best management practices for soil C in the Partnership region, and to design a risk/cost effectiveness framework to make comparative assessments of each viable sink, taking into account economic costs, offsetting benefits, scale of sequestration opportunities, spatial and time dimensions, environmental risks, and long-term viability. Scientifically sound information on MMV is critical for public acceptance of these technologies. Two key deliverables were completed in the second quarter--a literature review/database to assess the soil carbon on rangelands, and the draft protocols, contracting options for soil carbon trading. The protocols developed for soil carbon trading are unique and provide a key component of the mechanisms that might be used to efficiently sequester GHG and reduce CO{sub 2} concentrations. While no key deliverables were due during the third quarter, progress on other deliverables is noted in the PowerPoint presentations and in this report. A series of meetings held during the second and third quarters have laid the foundations for assessing the issues surrounding carbon sequestration in this region, the need for a holistic approach to meeting energy demands and economic development potential, and the implementation of government programs or a market-based setting for soil C credits. These meetings provide a connection to stakeholders in the region and a basis on which to draw for the DOE PEIS hearings. In the fourth quarter, three deliverables have been completed, some in draft form to be revised and updated to include Wyoming. This is due primarily to some delays in funding to LANL and INEEL and the approval of a supplemental proposal to include Wyoming in much of the GIS data sets, analysis, and related materials. The deliverables are discussed in the following sections and greater details are provided in the materials that are attached to this report. In August 2004, a presentation was made to Pioneer Hi-Bred, discussing the Partnership and the synergies with terrestrial sequestration, agricultural industries, and ongoing, complimentary USDA efforts. The Partnership organized a Carbon session at the INRA 2004 Environmental and Subsurface Science Symposium in September 2004; also in September, a presentation was made to the Wyoming Carbon Sequestration Advisory Committee, followed up with a roundtable discussion.« less

Literacy in Language and Mathematics: More in Common Than You Think

ERIC Educational Resources Information Center

Thompson, Denisse R.; Rubenstein, Rheta N.

2014-01-01

This paper shares perspectives on literacy in mathematics, particularly highlighting commonalities with literacy in language arts. We discuss levels of language development appropriate for the mathematics classroom, issues related to mathematical definitions, implied meanings in many mathematics concepts, and the importance of justification. We…

How much will afforestation of former cropland influence soil C stocks? A synthesis of paired sampling, chronosequence sampling and repeated sampling studies

NASA Astrophysics Data System (ADS)

Vesterdal, Lars; Hansen, K.; Stupak, I.; Don, Axel; Poeplau, C.; Leifeld, Jens; van Wesemael, Bas

2010-05-01

The need for documentation of land-use change effects on soil C is high on the agenda in most signatory countries to the Kyoto Protocol. Large land areas in Europe have experienced land-use change from cropland to forest since 1990 by direct afforestation as well as abandonment and regrowth of marginally productive cropland. Soil C dynamics following land-use change remain highly uncertain due to a limited number of available studies and due to influence of interacting factors such as land use history, soil type, and climate. Common approaches for estimation of potential soil C changes following land-use change are i) paired sampling of plots with a long legacy of different land uses, ii) chronosequence studies of land-use change, and lastly iii) repeated sampling of plots subject to changed land use. This paper will synthesize the quantitative effects of cropland afforestation on soil C sequestration based on all three approaches and will report on related work within Cost 639. Paired plots of forest and cropland were used to study the general differences between soil C stocks in the two land uses. At 27 sites in Denmark distributed among different regions and soil types forest floor and mineral soil were sampled in and around soil pits. Soil C stocks were higher in forest than cropland (mean difference 22 Mg C ha-1 to 1 m depth). This difference was caused solely by the presence of a forest floor in forests; mineral soil C stocks were similar (108 vs. 109 Mg C ha-1) in the two land uses regardless of soil type and the soil layers considered. The chronosequence approach was employed in the AFFOREST project for evaluation of C sequestration in biomass and soils following afforestation of cropland. Two oak (Quercus robur) and four Norway spruce (Picea abies) afforestation chronosequences (age range 1 to 90 years) were studied in Denmark, Sweden and the Netherlands. Forest floor and mineral soil (0-25 cm) C contents were as a minimum unchanged and in most cases there was net C sequestration (range 0-1.3 Mg C ha-1 yr-1). The allocation of sequestered soil C was quite different among chronosequences; forest floors consistently sequestered C (0.1-0.7 Mg C ha-1 yr-1) but there was no general pattern in mineral soil C sequestration. While the paired sampling and the chronosequence approaches both may be confounded by site factors other than the land use, repeated sampling of plots best addresses the pure land-use change effect. Repeated sampling after 18 years was done in a systematic 7x7 km grid to address soil C changes in 15 cropland plots that were converted to forest (7-22 years since afforestation). Consistent with the other two approaches, detectable soil C changes were confined to the forest floor component; forest floor C sequestration rates were 0.24 Mg C ha-1 yr-1 while no changes were detected for mineral soils. The three approaches to estimation of soil C sequestration indeed point to a common conclusion: The potential for soil C sequestration is mainly confined to the forest floor whereas notable C sequestration is less likely to occur in the mineral soil. However, more generalizable knowledge is badly needed for reporting of land-use change effects on mineral soil C pools. WG II of Cost 639 and the FP7 project GHG Europe is currently establishing a database of LUC studies. This database will be used to establish so-called Carbon Response Functions (CRF), i.e. simple models predicting the annual rate of change in soil C pools. These CRFs may serve as tools for syntheses of land-use change effects for Europe as well as for improved reporting of soil C dynamics following land-use change.

Comparaison de la performance environnementale de la production thermique d'electricite avec et sans sequestration geologique du dioxyde de carbone

NASA Astrophysics Data System (ADS)

Bellerive, Nathalie

The research project hypothesis is that CO2 capture and sequestration technologies (CSC) leads to a significant decrease in global warming, but increases the impact of all other aspects of the study. This is because other processes used for CO2 capture and sequestration require additional quantities of raw materials and energy. Two other objectives are described in this project. The first is the modeling of an Integrated Gasification Combined Cycle power plant for which there is no known generic data. The second is to select the right hypothesis regarding electrical production technologies, CO2 capture, compression and transportation by pipeline and finally sequestration. "Life Cycle Assessment" (LCA) analyses were chosen for this research project. LCA is an exhaustive quantitative method used to evaluate potential environmental impacts associated with a product, a service or an activity from resource extraction to waste elimination. This tool is governed by ISO 14 040 through ISO 14 049 and is sustained by the Society of Environmental Toxicology and Chemistry (SETAC) and the United Nations Environment Program (UNEP). Two power plants were studied, the Integrated Gasification Combined Cycle (IGCC) power plant and the Natural Gas Combined Cycle (NGCC) power plant. In order to sequester CO2 in geological formation, it is necessary to extract CO2from emission flows. For the IGCC power plant, CO 2 was captured before the burning phase. For the NGCC power plant, the capture was done during the afterburning phase. Once the CO2 was isolated, it was compressed and directed through a transportation pipe 1 000 km in length on the ground surface and in the sea. It is hypothesized that the power plant is 300 km from the shore and the sequestration platform 700 km from France's shore, in the North Sea. The IGCC power plant modeling and data selection regarding CO2 capture and sequestration were done by using primary data from the industry and the Ecoinvent generic database (Version 1.2). This database was selected due to its European source. Finally, technical calculations and literature were used to complete the data inventory. This was validated by electrical experts in order to increase data and modeling precision. Results were similar for IGCC and NGCC power plants using Impact 2002+, an impacts analysis method. Global warming potential decreased by 67% with the implementation of CO2 capture and sequestration compared to systems without CSC. Results for all others impacts categories, demonstrated an increase from 16% to 116% in relative proportions compared to systems without CSC. The main contributor was the additional quantity of energy required to operate CO2 capture and compression facilities. This additional energy negatively affected the power plant's global efficiency because of the increase in the quantity of fossil fuel that needed to be extracted and consumed. The increase in other impacts was mainly due to additional electricity, fossil fuel (for extracting, treatment and transportation) and additional emissions generated during power plant operations. A scenario analysis was done to study the sensitivity and variability of uncertain data during the software modeling process of a power plant. Data on power plant efficiency is the most variable and sensitive during modeling, followed by the length of the transportation pipe and the leaking rate during CO2 sequestration. This result analysis is interesting because it led to the maximum efficiency scenario with capture (with a short CO 2 transportation distance and a low leaking rate) obtaining better results on all impact category indicators, compared to the minimum efficiency scenario without capture. In fact, positive results on all category indicators were possible during the system comparison between the two cases (with and without capture). (Abstract shortened by UMI.)

A Multi-Level Approach to Outreach for Geologic Sequestration Projects

USGS Publications Warehouse

Greenberg, S.E.; Leetaru, H.E.; Krapac, I.G.; Hnottavange-Telleen, K.; Finley, R.J.

2009-01-01

Public perception of carbon capture and sequestration (CCS) projects represents a potential barrier to commercialization. Outreach to stakeholders at the local, regional, and national level is needed to create familiarity with and potential acceptance of CCS projects. This paper highlights the Midwest Geological Sequestration Consortium (MGSC) multi-level outreach approach which interacts with multiple stakeholders. The MGSC approach focuses on external and internal communication. External communication has resulted in building regional public understanding of CCS. Internal communication, through a project Risk Assessment process, has resulted in enhanced team communication and preparation of team members for outreach roles. ?? 2009 Elsevier Ltd. All rights reserved.

Mathematical Caring Relations: A Challenging Case

ERIC Educational Resources Information Center

Hackenberg, Amy

2010-01-01

Developed from Noddings's (2002) care theory, von Glasersfeld's (1995) constructivism, and Ryan and Frederick's (1997) notion of subjective vitality, a mathematical caring relation (MCR) is a quality of interaction between a student and a mathematics teacher that conjoins affective and cognitive realms in the process of aiming for mathematical…

Construction Industry Related Mathematics: Seventh Grade.

ERIC Educational Resources Information Center

Mundell, Scott

The field tested construction industry-related mathematics unit is intended to familiarize seventh grade students with various facets of the construction industry, including the various occupations available and the mathematical abilities and other skills and training necessary to pursue an occupation in the industry. The final set of activities…

Simulating soil C stability with mechanistic systems models: a multisite comparison of measured fractions and modelled pools

NASA Astrophysics Data System (ADS)

Robertson, Andy; Schipanski, Meagan; Sherrod, Lucretia; Ma, Liwang; Ahuja, Lajpat; McNamara, Niall; Smith, Pete; Davies, Christian

2016-04-01

Agriculture, covering more than 30% of global land area, has an exciting opportunity to help combat climate change by effectively managing its soil to promote increased C sequestration. Further, newly sequestered soil carbon (C) through agriculture needs to be stored in more stable forms in order to have a lasting impact on reducing atmospheric CO2 concentrations. While land uses in different climates and soils require different management strategies, the fundamental mechanisms that regulate C sequestration and stabilisation remain the same. These mechanisms are used by a number of different systems models to simulate C dynamics, and thus assess the impacts of change in management or climate. To evaluate the accuracy of these model simulations, our research uses a multidirectional approach to compare C stocks of physicochemical soil fractions collected at two long-term agricultural sites. Carbon stocks for a number of soil fractions were measured at two sites (Lincoln, UK; Colorado, USA) over 8 and 12 years, respectively. Both sites represent managed agricultural land but have notably different climates and levels of disturbance. The measured soil fractions act as proxies for varying degrees of stability, with C contained within these fractions relatable to the C simulated within the soil pools of mechanistic systems models1. Using stable isotope techniques at the UK site, specific turnover times of C within the different fractions were determined and compared with those simulated in the pools of 3 different models of varying complexity (RothC, DayCent and RZWQM2). Further, C dynamics and N-mineralisation rates of the measured fractions at the US site were assessed and compared to results of the same three models. The UK site saw a significant increase in C stocks within the most stable fractions, with topsoil (0-30cm) sequestration rates of just over 0.3 tC ha-1 yr-1 after only 8 years. Further, the sum of all fractions reported C sequestration rates of nearly 1.0 tC ha-1 yr-1. At the US site, however, topsoil C sequestration was less consistent noting considerable variation over the 12 years of measured data. Both sites showed noteworthy discrepancies when model-simulated C was compared with measured C. While all three models were able to simulate the bulk C stocks within reasonable degrees of uncertainty, the accuracy broke down considerably when this bulk soil was split into fractions/pools. Using the data collected and accounting for the differences in model structure, we present potential next steps in model development as well as the variables that should be measured when aiming to reduce the uncertainties inherent in mechanistic systems models. References 1 - Zimmermann et al., 2007. Measured soil organic matter fractions can be related to pools in the RothC model. European Journal of Soil Science, 58:658-667.

Computational Modeling of the Geologic Sequestration of Carbon Dioxide

EPA Science Inventory

Geologic sequestration of CO2 is a component of C capture and storage (CCS), an emerging technology for reducing CO2 emissions to the atmosphere, and involves injection of captured CO2 into deep subsurface formations. Similar to the injection of hazardous wastes, before injection...

Carbon sequestration in wood and paper products

Treesearch

Kenneth E. Skog; Geraldine A. Nicholson

2000-01-01

Recognition that increasing levels of CO2 in the atmosphere will affect the global climate has spurred research into reduction global carbon emissions and increasing carbon sequestration. The main nonhuman sources of atmospheric CO2 are animal respiration and decay of biomass. However, increases in atmospheric levels are...

Brush management effects on soil carbon sequestration in sagebrush-dominated rangelands

USDA-ARS?s Scientific Manuscript database

Scientific information regarding soil organic carbon (SOC) sequestration in western rangelands, especially those with a sagebrush (Artemisia spp.) component and in lower rainfall areas (<350 mm), remains a major knowledge gap in understanding the effects of land management. We sampled soils from two...

SUBSURFACE PROPERTY RIGHTS: IMPLICATIONS FOR GEOLOGIC CO2 SEQUESTRATION

EPA Science Inventory

The chapter discusses subsurface property rights as they apply to geologic sequestration (GS) of carbon dioxide (CO2). GS projects inject captured CO2 into deep (greater than ~1 km) geologic formations for the explicit purpose of avoiding atmospheric emission of CO2. Because of t...

Carbon Sequestration in Wetland Soils of the Northern Gulf of Mexico Coastal Region

EPA Science Inventory

Coastal wetlands play an important but complex role in the global carbon cycle, contributing to the ecosystem service of greenhouse gas regulation through carbon sequestration. Although coastal wetlands occupy a small percent of the total US land area, their potential for carbon...

An Alternative View of the Climate Warming Mitigation Potential of U.S. Temperate Forests

EPA Science Inventory

Many U.S. federal and non-governmental agencies promote forestation as a means to mitigate climate warming because of the carbon sequestration potential of forests. This biogeochemical-oriented carbon sequestration policy is somewhat inconsistent with a decade or more of researc...

Impact of Three-Phase Relative Permeability and Hysteresis Models on Forecasts of Storage Associated With CO2-EOR

NASA Astrophysics Data System (ADS)

Jia, Wei; McPherson, Brian; Pan, Feng; Dai, Zhenxue; Moodie, Nathan; Xiao, Ting

2018-02-01

Geological CO2 sequestration in conjunction with enhanced oil recovery (CO2-EOR) includes complex multiphase flow processes compared to CO2 storage in deep saline aquifers. Two of the most important factors affecting multiphase flow in CO2-EOR are three-phase relative permeability and associated hysteresis, both of which are difficult to measure and are usually represented by numerical interpolation models. The purpose of this study is to improve understanding of (1) the relative impacts of different three-phase relative permeability models and hysteresis models on CO2 trapping mechanisms, and (2) uncertainty associated with these two factors. Four different three-phase relative permeability models and three hysteresis models were applied to simulations of an active CO2-EOR site, the SACROC unit located in western Texas. To eliminate possible bias of deterministic parameters, we utilized a sequential Gaussian simulation technique to generate 50 realizations to describe heterogeneity of porosity and permeability, based on data obtained from well logs and seismic survey. Simulation results of forecasted CO2 storage suggested that (1) the choice of three-phase relative permeability model and hysteresis model led to noticeable impacts on forecasted CO2 sequestration capacity; (2) impacts of three-phase relative permeability models and hysteresis models on CO2 trapping are small during the CO2-EOR injection period, and increase during the post-EOR CO2 injection period; (3) the specific choice of hysteresis model is more important relative to the choice of three-phase relative permeability model; and (4) using the recommended three-phase WAG (Water-Alternating-Gas) hysteresis model may increase the impact of three-phase relative permeability models and uncertainty due to heterogeneity.

"Effective" Mathematics Teaching of African American Adolescents and the Development of a Mathematics Identity

ERIC Educational Resources Information Center

Green, Marcus Allen

2016-01-01

In order to increase mathematics achievement, persistence, and participation in mathematics-related careers and majors for African American adolescents, researchers have discussed the need for students to develop positive mathematical identities (English-Clarke, Slaughter-Defoe, & Martin, 2012; Gutstein, 2003; Larnell, 2013; Martin, 2000,…

Abstraction in Mathematics and Mathematics Learning

ERIC Educational Resources Information Center

Mitchelmore, Michael; White, Paul

2004-01-01

It is claimed that, since mathematics is essentially a self-contained system, mathematical objects may best be described as "abstract-apart." On the other hand, fundamental mathematical ideas are closely related to the real world and their learning involves empirical concepts. These concepts may be called "abstract-general" because they embody…

The Mathematical Sciences: A Report.

ERIC Educational Resources Information Center

National Academy of Sciences, Washington, DC.

Presented are position statements for the support of the mathematical sciences and a description of the present state of both research and education in mathematics and related disciplines. The report calls attention to the penetration of mathematics and mathematical modes of thought into many new areas of scholarship and the resultant increase in…

Locating Mathematics within Post-16 Vocational Education in England

ERIC Educational Resources Information Center

Dalby, Diane; Noyes, Andrew

2016-01-01

The political importance of mathematics in post-16 education is clear. Far less clear is how mathematics does and should relate to vocational education. Successive mathematics curricula (e.g. core skills, key skills) have been developed in England with vocational learners in mind. Meanwhile, general mathematics qualifications remain largely…

Why Do Early Mathematics Skills Predict Later Reading? The Role of Mathematical Language

ERIC Educational Resources Information Center

Purpura, David J.; Logan, Jessica A. R.; Hassinger-Das, Brenna; Napoli, Amy R.

2017-01-01

A growing body of evidence indicates that the development of mathematics and literacy skills is highly related. The importance of literacy skills--specifically language--for mathematics development has been well rationalized. However, despite several prominent studies indicating that mathematics skills are highly predictive of literacy…

Immobilized carbonic anhydrase on mesoporous cruciate flower-like metal organic framework for promoting CO2 sequestration.

PubMed

Ren, Sizhu; Feng, Yuxiao; Wen, Huan; Li, Conghai; Sun, Baoting; Cui, Jiandong; Jia, Shiru

2018-05-25

CO 2 capture by immobilized carbonic anhydrase (CA) has become an alternative and environmental friendly approach in CO 2 sequestration technology. However, the immobilized CA usually exhibits low CO 2 sequestration efficiency due to no gas adsorption function for the conventional CA supports. Metal organic frameworks (MOFs) are an excellent material for gas adsorption and enzyme immobilization. Herein, a combined immobilization system of CA and ZIF-8 with cruciate flower-like morphology for CO 2 adsorption was prepared for the first time by adsorbing CA onto ZIF-8. The immobilization efficiency was greater than 95%, and the maximum activity recovery reached 75%, indicating the highly efficient immobilization process. The resultant CA@ZIF-8 composites exhibited outstanding thermostability, the tolerance against denaturants, and reusability compared with free CA. Furthermore, we demonstrated for the first time that the shape of ZIF-8 could be controlled by adjusting concentrations of Zn 2+ ions at the high concentration of 2-methylimidazole (1 M). More importantly, we also demonstrated the applicability of the CA@ZIF-8 composites to the sequestration of CO 2 in carbonate minerals. The yields of the CaCO 3 obtained by using CA@ZIF-8 composites were 22-folds compared to free CA. Thus, this CA@ZIF-8 composite can be successfully used as a robust biocatalyst for sequestration of CO 2 . Copyright © 2018 Elsevier B.V. All rights reserved.

NEAT1 long noncoding RNA regulates transcription via protein sequestration within subnuclear bodies

PubMed Central

Hirose, Tetsuro; Virnicchi, Giorgio; Tanigawa, Akie; Naganuma, Takao; Li, Ruohan; Kimura, Hiroshi; Yokoi, Takahide; Nakagawa, Shinichi; Bénard, Marianne; Fox, Archa H.; Pierron, Gérard

2014-01-01

Paraspeckles are subnuclear structures formed around nuclear paraspeckle assembly transcript 1 (NEAT1)/MENε/β long noncoding RNA (lncRNA). Here we show that paraspeckles become dramatically enlarged after proteasome inhibition. This enlargement is mainly caused by NEAT1 transcriptional up-regulation rather than accumulation of undegraded paraspeckle proteins. Of interest, however, using immuno–electron microscopy, we find that key paraspeckle proteins become effectively depleted from the nucleoplasm by 50% when paraspeckle assembly is enhanced, suggesting a sequestration mechanism. We also perform microarrays from NEAT1-knockdown cells and find that NEAT1 represses transcription of several genes, including the RNA-specific adenosine deaminase B2 (ADARB2) gene. In contrast, the NEAT1-binding paraspeckle protein splicing factor proline/glutamine-rich (SFPQ) is required for ADARB2 transcription. This leads us to hypothesize that ADARB2 expression is controlled by NEAT1-dependent sequestration of SFPQ. Accordingly, we find that ADARB2 expression is strongly reduced upon enhanced SFPQ sequestration by proteasome inhibition, with concomitant reduction in SFPQ binding to the ADARB2 promoter. Finally, NEAT1−/− fibroblasts are more sensitive to proteasome inhibition, which triggers cell death, suggesting that paraspeckles/NEAT1 attenuates the cell death pathway. These data further confirm that paraspeckles are stress-responsive nuclear bodies and provide a model in which induced NEAT1 controls target gene transcription by protein sequestration into paraspeckles. PMID:24173718

Feasibility Assessment of CO2 Sequestration and Enhanced Recovery in Gas Shale Reservoirs

NASA Astrophysics Data System (ADS)

Vermylen, J. P.; Hagin, P. N.; Zoback, M. D.

2008-12-01

CO2 sequestration and enhanced methane recovery may be feasible in unconventional, organic-rich, gas shale reservoirs in which the methane is stored as an adsorbed phase. Previous studies have shown that organic-rich, Appalachian Devonian shales adsorb approximately five times more carbon dioxide than methane at reservoir conditions. However, the enhanced recovery and sequestration concept has not yet been tested for gas shale reservoirs under realistic flow and production conditions. Using the lessons learned from previous studies on enhanced coalbed methane (ECBM) as a starting point, we are conducting laboratory experiments, reservoir modeling, and fluid flow simulations to test the feasibility of sequestration and enhanced recovery in gas shales. Our laboratory work investigates both adsorption and mechanical properties of shale samples to use as inputs for fluid flow simulation. Static and dynamic mechanical properties of shale samples are measured using a triaxial press under realistic reservoir conditions with varying gas saturations and compositions. Adsorption is simultaneously measured using standard, static, volumetric techniques. Permeability is measured using pulse decay methods calibrated to standard Darcy flow measurements. Fluid flow simulations are conducted using the reservoir simulator GEM that has successfully modeled enhanced recovery in coal. The results of the flow simulation are combined with the laboratory results to determine if enhanced recovery and CO2 sequestration is feasible in gas shale reservoirs.

L-phenylalanyl-L-glutamate-stimulated, chloride-dependent glutamate binding represents glutamate sequestration mediated by an exchange system.

PubMed

Kessler, M; Petersen, G; Vu, H M; Baudry, M; Lynch, G

1987-04-01

Stimulation of glutamate binding by the dipeptide L-phenylalanyl-L-glutamate (Phe-Glu) was inhibited by the peptidase inhibitor bestatin, suggesting that the stimulation was caused by glutamate liberated from the dipeptide and not by the dipeptide itself. It further suggests that this form of glutamate binding should be reinterpreted as glutamate sequestration and that stimulation of binding both by dipeptides and after preincubation with high concentrations of glutamate is likely to be due to counterflow accumulation. Several other criteria indicate that most of glutamate binding stimulated by chloride represents glutamate sequestration: Binding is reduced when the osmolarity of the incubation medium is increased, when membranes incubated with [3H]glutamate are lysed before filtration, and when membranes are made permeable by transient exposure to saponin. Moreover, dissociation of bound glutamate after a 100-fold dilution of the incubation medium is accelerated about 50 times by the addition of glutamate to the dilution medium. This result would be anomalous if glutamate were bound to a receptor site; it suggests instead that glutamate is transported in and out of membrane vesicles by a transport system that preferentially mediates exchange between internal and external glutamate. Glutamate binding contains a component of glutamate sequestration even when measured in the absence of chloride. Sequestration is adequately abolished only after treating membranes with detergents; even extensive lysis, sonication, and freezing/thawing may be insufficient.

Carbon Sequestration by Fruit Trees - Chinese Apple Orchards as an Example

PubMed Central

Wu, Ting; Wang, Yi; Yu, Changjiang; Chiarawipa, Rawee; Zhang, Xinzhong; Han, Zhenhai; Wu, Lianhai

2012-01-01

Apple production systems are an important component in the Chinese agricultural sector with 1.99 million ha plantation. The orchards in China could play an important role in the carbon (C) cycle of terrestrial ecosystems and contribute to C sequestration. The carbon sequestration capability in apple orchards was analyzed through identifying a set of potential assessment factors and their weighting factors determined by a field model study and literature. The dynamics of the net C sink in apple orchards in China was estimated based on the apple orchard inventory data from 1990s and the capability analysis. The field study showed that the trees reached the peak of C sequestration capability when they were 18 years old, and then the capability began to decline with age. Carbon emission derived from management practices would not be compensated through C storage in apple trees before reaching the mature stage. The net C sink in apple orchards in China ranged from 14 to 32 Tg C, and C storage in biomass from 230 to 475 Tg C between 1990 and 2010. The estimated net C sequestration in Chinese apple orchards from 1990 to 2010 was equal to 4.5% of the total net C sink in the terrestrial ecosystems in China. Therefore, apple production systems can be potentially considered as C sinks excluding the energy associated with fruit production in addition to provide fruits. PMID:22719974

Carbon sequestration by fruit trees--Chinese apple orchards as an example.

PubMed

Wu, Ting; Wang, Yi; Yu, Changjiang; Chiarawipa, Rawee; Zhang, Xinzhong; Han, Zhenhai; Wu, Lianhai

2012-01-01

Apple production systems are an important component in the Chinese agricultural sector with 1.99 million ha plantation. The orchards in China could play an important role in the carbon (C) cycle of terrestrial ecosystems and contribute to C sequestration. The carbon sequestration capability in apple orchards was analyzed through identifying a set of potential assessment factors and their weighting factors determined by a field model study and literature. The dynamics of the net C sink in apple orchards in China was estimated based on the apple orchard inventory data from 1990s and the capability analysis. The field study showed that the trees reached the peak of C sequestration capability when they were 18 years old, and then the capability began to decline with age. Carbon emission derived from management practices would not be compensated through C storage in apple trees before reaching the mature stage. The net C sink in apple orchards in China ranged from 14 to 32 Tg C, and C storage in biomass from 230 to 475 Tg C between 1990 and 2010. The estimated net C sequestration in Chinese apple orchards from 1990 to 2010 was equal to 4.5% of the total net C sink in the terrestrial ecosystems in China. Therefore, apple production systems can be potentially considered as C sinks excluding the energy associated with fruit production in addition to provide fruits.

Transient dynamics of terrestrial carbon storage: Mathematical foundation and numeric examples

DOE PAGES

Luo, Yiqi; Shi, Zheng; Lu, Xingjie; ...

2016-09-16

Terrestrial ecosystems absorb roughly 30% of anthropogenic CO 2 emissions since preindustrial era, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling, experimental, and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under climate change is still not very clear. Here we develop a new framework for understanding transient dynamics of terrestrial C storage through mathematical analysis and numerical experiments. Our analysis indicates that the ultimate force driving ecosystem C storage change is the C storage capacity, which is jointly determined by ecosystem C input (e.g., net primary production,more » NPP) and residence time. Since both C input and residence time vary with time, the C storage capacity is time-dependent and acts as a moving attractor that actual C storage chases. The rate of change in C storage is proportional to the C storage potential, the difference between the current storage and the storage capacity. The C storage capacity represents instantaneous responses of the land C cycle to external forcing, whereas the C storage potential represents the internal capability of the land C cycle to influence the C change trajectory in the next time step. The influence happens through redistribution of net C pool changes in a network of pools with different residence times. Furthermore, this and our other studies have demonstrated that one matrix equation can exactly replicate simulations of most land C cycle models (i.e., physical emulators). As a result, simulation outputs of those models can be placed into a three-dimensional (3D) parameter space to measure their differences. The latter can be decomposed into traceable components to track the origins of model uncertainty. Moreover, the emulators make data assimilation computationally feasible so that both C flux- and pool-related datasets can be used to better constrain model predictions of land C sequestration. We also propose that the C storage potential be the targeted variable for research, market trading, and government negotiation for C credits.« less

Transient dynamics of terrestrial carbon storage: Mathematical foundation and numeric examples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Yiqi; Shi, Zheng; Lu, Xingjie

Terrestrial ecosystems absorb roughly 30% of anthropogenic CO 2 emissions since preindustrial era, but it is unclear whether this carbon (C) sink will endure into the future. Despite extensive modeling, experimental, and observational studies, what fundamentally determines transient dynamics of terrestrial C storage under climate change is still not very clear. Here we develop a new framework for understanding transient dynamics of terrestrial C storage through mathematical analysis and numerical experiments. Our analysis indicates that the ultimate force driving ecosystem C storage change is the C storage capacity, which is jointly determined by ecosystem C input (e.g., net primary production,more » NPP) and residence time. Since both C input and residence time vary with time, the C storage capacity is time-dependent and acts as a moving attractor that actual C storage chases. The rate of change in C storage is proportional to the C storage potential, the difference between the current storage and the storage capacity. The C storage capacity represents instantaneous responses of the land C cycle to external forcing, whereas the C storage potential represents the internal capability of the land C cycle to influence the C change trajectory in the next time step. The influence happens through redistribution of net C pool changes in a network of pools with different residence times. Furthermore, this and our other studies have demonstrated that one matrix equation can exactly replicate simulations of most land C cycle models (i.e., physical emulators). As a result, simulation outputs of those models can be placed into a three-dimensional (3D) parameter space to measure their differences. The latter can be decomposed into traceable components to track the origins of model uncertainty. Moreover, the emulators make data assimilation computationally feasible so that both C flux- and pool-related datasets can be used to better constrain model predictions of land C sequestration. We also propose that the C storage potential be the targeted variable for research, market trading, and government negotiation for C credits.« less

Permanence of agricultural afforestation for carbon sequestration under stylized carbon markets in the U.S.

Treesearch

David Haim; Eric White; Ralph J. Alig

2014-01-01

This paper examines the permanence of agricultural land afforestation under stylized carbon markets at the regional level in the US. Attention is focused on Southern and Midwest regions which historically have experienced a relatively large amount of land-use change between the agriculture and forest sectors. The Forest and Agriculture Sector Optimization Model–...

Litterfall and decomposition in relation to soil carbon pools along a secondary forest chronosequence in Puerto Rico

Treesearch

R. Ostertag; E. Marín-Spiotta; W.L. Silver; J. Schulten

2008-01-01

Secondary forests are becoming increasingly widespread in the tropics, but our understanding of how secondary succession affects carbon (C) cycling and C sequestration in these ecosystems is limited. We used a well-replicated 80-year pasture to forest successional chronosequence and primary forest in Puerto Rico to explore the relationships among litterfall, litter...

A Study of Federal Academic Earmarks and Research Funding in Relation to the Institutional Research Culture of Research University/High (RU/H) Institutions in Mississippi

ERIC Educational Resources Information Center

Young, James Hubert, III

2013-01-01

Nationally, reductions in public funding for higher education, a stagnate economy, looming sequestration, and a divisive political culture present a complex and challenging dynamic for research universities in pursuit of external funding for their research programs and infrastructure needs. These universities and their research initiatives have…

Mitigating climate change through small-scale forestry in the USA: opportunities and challenges

Treesearch

Susan Charnley; David Diaz; Hannah Gosnell

2010-01-01

Forest management for carbon sequestration is a low-cost, low-technology, relatively easy way to help mitigate global climate change that can be adopted now while additional long-term solutions are developed. Carbon-oriented management of forests also offers forest owners an opportunity to obtain a new source of income, and commonly has environmental co-benefits. The...

Baseline and projected future carbon storage and carbon fluxes in ecosystems of Hawai‘i

Treesearch

P.C. Selmants; C.P. Giardina; J.D. Jacobi; Zhiliang  Zhu

2017-01-01

Hawaii is unique among the United States because of its tropical climate, geographic isolation, high rates of species endemism and discontinuous land mass. The year-round warm, wet climate on the windward sides of islands and the high fertility of relatively young volcanically derived soils are ideal conditions for carbon input, storage and carbon sequestration in...

Longitudinal Associations between Executive Control and Developing Mathematical Competence in Preschool Boys and Girls

PubMed Central

Clark, Caron A.C.; Sheffield, Tiffany D.; Wiebe, Sandra A.; Espy, Kimberly Andrews

2012-01-01

Executive control (EC) is related to mathematics performance in middle childhood. However, little is known regarding how EC and informal numeracy differentially support mathematics skill acquisition in preschoolers. A sample of preschoolers (115 girls, 113 boys), stratified by social risk, completed an EC task battery at 3 years, informal numeracy assessments at 3.75 and 4.5 years, and a broad mathematics assessment during kindergarten. Strong associations were observed between latent EC at 3 and mathematics achievement in kindergarten, which remained robust after accounting for earlier informal numeracy, socio-economic status, language and processing speed. Relations between EC and mathematics achievement were stronger in girls than boys. Findings highlight the unique role of EC in predicting which children may have difficulty transitioning to formal mathematics instruction. PMID:23006040

LDL receptor-related protein mediates cell-surface clustering and hepatic sequestration of chylomicron remnants in LDLR-deficient mice.

PubMed

Yu, K C; Chen, W; Cooper, A D

2001-06-01

It has been proposed that in the liver, chylomicron remnants (lipoproteins carrying dietary lipid) may be sequestered before being internalized by hepatocytes. To study this, chylomicron remnants labeled with a fluorescent dye were perfused into isolated livers of LDL receptor-deficient (LDLR-deficient) mice (Ldlr(-/-)) and examined by confocal microscopy. In contrast to livers from normal mice, there was clustering of the chylomicron remnants on the cell surface in the space of DISSE: These remnant clusters colocalized with clusters of LDLR-related protein (LRP) and could be eliminated by low concentrations of receptor-associated protein, an inhibitor of LRP. When competed with ligands of heparan sulfate proteoglycans (HSPGs), the remnant clusters still appeared but were fewer in number, although syndecans (membrane HSPGs) colocalized with the remnant clusters. This suggests that the clustering of remnants is not dependent on syndecans but that the syndecans may modify the binding of remnants. These results establish that sequestration is a novel process, the clustering of remnants in the space of DISSE: The clustering involves remnants binding to the LRP, and this may be stabilized by binding with syndecans, eventually followed by endocytosis.

Wetlands in The Netherlands and New Zealand: optimising biodiversity and carbon sequestration during urbanisation.

PubMed

van Roon, Marjorie R

2012-06-30

The halting of biodiversity decline of wetlands necessitates ecosystem protection, restoration and re-creation of all wetland types preferably in all suitable landscapes. As peat wetlands (bogs and fens) are superior as carbon stores, and because of their rarity they have a higher biodiversity value relative to other wetland types, they need to be prioritised for protection and restoration. The hydrological, pH, and nutrient conditions essential to each type of wetland that need to be understood and provided for during development are discussed for The Netherlands' and New Zealand. Case studies describe freshwater wetland management and challenges during urbanisation in the Stad van de Zon and Blauwestad in The Netherlands, and in the Styx valley and Pegasus in Christchurch, New Zealand. A summary of the history of urbanisation and wetland destruction, and of biodiversity management for each country provides a context for the case studies. These case studies demonstrate the degree to which the relative values of bogs, fens and swamps, with respect to biodiversity and carbon sequestration, are understood and managed using diverse protection measures, within the boundaries of new urban developments and in adjacent ecological corridors. Copyright © 2012 Elsevier Ltd. All rights reserved.

When Do Girls Prefer Football to Fashion? An Analysis of Female Underachievement in Relation to "Realistic" Mathematics Context.

ERIC Educational Resources Information Center

Boaler, Jo

1994-01-01

Reports on a study of the move away from abstract calculations toward "mathematics in context" among 50 British female secondary school students. Discusses implications of findings in relation to reported female underachievement and disinterest in school mathematics. (CFR)

Preservice Mathematics Teachers' Experiences about Function and Equation Concepts

ERIC Educational Resources Information Center

Dede, Yuksel; Soybas, Danyal

2011-01-01

The purpose of this study is to determine the experience of mathematics preservice teachers related to function and equation concepts and the relations between them. Determining preservice mathematics teachers' understanding of function and equation concepts has great importance since it directly affects their future teaching careers. Data were…

On Relative and Absolute Conviction in Mathematics

ERIC Educational Resources Information Center

Weber, Keith; Mejia-Ramos, Juan Pablo

2015-01-01

Conviction is a central construct in mathematics education research on justification and proof. In this paper, we claim that it is important to distinguish between absolute conviction and relative conviction. We argue that researchers in mathematics education frequently have not done so and this has lead to researchers making unwarranted claims…

Mathematical Thinking: Challenging Prospective Teachers to Do More than "Talk the Talk"

ERIC Educational Resources Information Center

Prendergast, Mark; Johnson, Patrick; Fitzmaurice, Olivia; Liston, Miriam; O'Keeffe, Lisa; O'Meara, Niamh

2014-01-01

This paper reports on a research project which aims to improve prospective mathematics teachers' relational understanding and pedagogical beliefs for teaching in second-level Irish classrooms. Prospective mathematics teachers complete their teacher education training with varying pedagogical beliefs, and often little relational understanding of…

An Investigation of Elementary Preservice Teachers' Self-Efficacy for Teaching Mathematics

ERIC Educational Resources Information Center

Giles, Rebecca McMahon; Byrd, Kelly O.; Bendolph, Angelia

2016-01-01

Research has consistently shown that teacher efficacy is related to a variety of desirable student outcomes, thus, making teacher efficacy an important factor in high quality mathematics instruction. The purpose of this study was to determine elementary preservice teachers' self-efficacy beliefs related to teaching mathematics. Forty-one…

Origins of the brain networks for advanced mathematics in expert mathematicians

PubMed Central

Amalric, Marie; Dehaene, Stanislas

2016-01-01

The origins of human abilities for mathematics are debated: Some theories suggest that they are founded upon evolutionarily ancient brain circuits for number and space and others that they are grounded in language competence. To evaluate what brain systems underlie higher mathematics, we scanned professional mathematicians and mathematically naive subjects of equal academic standing as they evaluated the truth of advanced mathematical and nonmathematical statements. In professional mathematicians only, mathematical statements, whether in algebra, analysis, topology or geometry, activated a reproducible set of bilateral frontal, Intraparietal, and ventrolateral temporal regions. Crucially, these activations spared areas related to language and to general-knowledge semantics. Rather, mathematical judgments were related to an amplification of brain activity at sites that are activated by numbers and formulas in nonmathematicians, with a corresponding reduction in nearby face responses. The evidence suggests that high-level mathematical expertise and basic number sense share common roots in a nonlinguistic brain circuit. PMID:27071124

Origins of the brain networks for advanced mathematics in expert mathematicians.

PubMed

Amalric, Marie; Dehaene, Stanislas

2016-05-03

The origins of human abilities for mathematics are debated: Some theories suggest that they are founded upon evolutionarily ancient brain circuits for number and space and others that they are grounded in language competence. To evaluate what brain systems underlie higher mathematics, we scanned professional mathematicians and mathematically naive subjects of equal academic standing as they evaluated the truth of advanced mathematical and nonmathematical statements. In professional mathematicians only, mathematical statements, whether in algebra, analysis, topology or geometry, activated a reproducible set of bilateral frontal, Intraparietal, and ventrolateral temporal regions. Crucially, these activations spared areas related to language and to general-knowledge semantics. Rather, mathematical judgments were related to an amplification of brain activity at sites that are activated by numbers and formulas in nonmathematicians, with a corresponding reduction in nearby face responses. The evidence suggests that high-level mathematical expertise and basic number sense share common roots in a nonlinguistic brain circuit.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christopher Liner

The objective of our work is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO{sub 2}, specifically better quantification and sensitivity for mapping of caprock integrity, fractures, and other potential leakage pathways. We utilize data and results developed through previous DOE-funded CO{sub 2} characterization project (DE-FG26-06NT42734) at the Dickman Field of Ness County, KS. Dickman is a type locality for the geology that will be encountered for CO{sub 2} sequestration projects from northern Oklahoma across the U.S. midcontinent to Indiana and Illinois. Since its discovery inmore » 1962, the Dickman Field has produced about 1.7 million barrels of oil from porous Mississippian carbonates with a small structural closure at about 4400 ft drilling depth. Project data includes 3.3 square miles of 3D seismic data, 142 wells, with log, some core, and oil/water production data available. Only two wells penetrate the deep saline aquifer. In a previous DOE-funded project, geological and seismic data were integrated to create a geological property model and a flow simulation grid. We believe that sequestration of CO{sub 2} will largely occur in areas of relatively flat geology and simple near surface, similar to Dickman. The challenge is not complex geology, but development of improved, lower-cost methods for detecting natural fractures and subtle faults. Our project used numerical simulation to test methods of gathering multicomponent, full azimuth data ideal for this purpose. Our specific objectives were to apply advanced seismic methods to aide in quantifying reservoir properties and lateral continuity of CO{sub 2} sequestration targets. The purpose of the current project is graduate and undergraduate student training related to improved 3D seismic technology that addresses key challenges related to monitoring movement and containment of CO{sub 2}, specifically better quantification and sensitivity for mapping of caprock integrity, fractures, and other potential leakage pathways. Specifically, our focus is fundamental research on (1) innovative narrow-band seismic data decomposition and interpretation, and (2) numerical simulation of advanced seismic data (multi-component, high density, full azimuth data) ideal for mapping of cap rock integrity and potential leakage pathways.« less

Mayamontana coccolobae (Basidiomycota), a new sequestrate taxon from Belize

Treesearch

Michael A. Castellano; James M. Trappe; D. Jean Lodge

2007-01-01

A new semi-hypogeous, sequestrate genus and species in the Basidiomycota is described from the Maya Mountains of Belize, where it was fruiting in association with Coccoloba belizensis. Mayamontana coccolobae is characterized by small, bright orange basidiomata with a friable, loculate, red-orange to red gleba and bilaterally...

Geological Sequestration of CO2 A Brief Overview and Potential for Application for Oklahoma

EPA Science Inventory

Geologic sequestration of CO2 is a component of C capture and storage (CCS), an emerging technology for reducing CO2 emissions to the atmosphere, and involves injection of captured CO2 into deep subsurface formations. Similar to the injection of hazardous wastes, before injection...

SUBSURFACE PROPERTY RIGHTS: IMPLICATIONS FOR GEOLOGIC CO2 SEQUESTRATION (PRESENTATION)

EPA Science Inventory

The paper discusses subsurface property rights as they apply to geologic sequestration (GS) of carbon dioxide (CO2). GS projects inject captured CO2 into deep (greater than ~1 km) geologic formations for the explicit purpose of avoiding atmospheric emission of CO2. Because of the...

Soil carbon

Treesearch

Charles H. Perry; Michael C. Amacher

2007-01-01

Why Is Soil Carbon Important? The sequestration of carbon by forest and agricultural soils has the potential to significantly reduce greenhouse gas concentrations (Pacala and Socolow 2004). Many countries are implementing field inventories of soil carbon, often combined with data from other sources, to estimate soil carbon sequestration rates and amounts (Kurz and Apps...