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Evaluation of carbon stock under major land use/land cover types for developing alternative land use scenarios for reducing greenhouse gas emissionsTessema Toru Demissie 06 1900 (has links)
In the dominantly small-scale subsistence agricultural system of Ethiopia, where most of the organic inputs are not returned to soil and land is not used based on its best suitability, the contribution of agriculture to climate change mitigation/adaptation through reduction of greenhouse gases emission is undermined. When this low-input agricultural practice is coupled with rugged topography, high population pressure, generally low soil fertility, and looming climate change, ensuring food and nutrition security of society as well as sustainable use of land resources is practically impossible. Under such circumstances, finding alternative land uses, through scientific investigation, that meet the triple mandates of climate-smart agriculture under current and future climate is imperative. In view of this, a study was conducted in Hades Sub-watershed, eastern Ethiopia, to evaluate the carbon stock of major land uses, evaluate suitability of land for rainfed production of sorghum (Sorghum bicolor L.), Maize (Zea mays L.), coffee (Coffea arabica), upland rice (Oryza sativa L.) and finger millet (Eleusine coracana L.), and project biomass production of late-maturing sorghum and maize varieties under changing climate and its contribution to carbon sequestration and reduction of greenhouse gases (GHGs) emission. Soil and vegetation samples were collected following recommended procedures. Secondary data on required crop parameters were collected for model calibration and validation in the biomass projection study made using the AquaCrop v6.0 model. Climate data of the study area was obtained from the National Meteorology Agency of Ethiopia and analyzed following standard procedures. Near-century (NC) (2017-2039) and Mid-century (MC) (2040-2069) climate was projected under two emission scenarios (RCP4.5 and RCP8.5) using four models (CNRM-CERFACS-CNRM-CM5, ICHEC-EC-Earth, MOHC-HadGEM2-ES, and MPI-M-MPI-ESM-LR) and a Multi-model Ensemble. Biomass production projection, for the climate projected under the two emission scenarios using the four models and the ensemble, was made for late-maturing sorghum (Muyira-1) and maize (BH661) varieties. From the projected biomass, organic carbon and its equivalent CO2 were estimated. Furthermore, adaptation measures, involving adjusting planting dates and irrigation, under the changing climate were evaluated for their influence on biomass production under the time slices, RCPs, and models mentioned above. The carbon stock assessment study was conducted on four major land uses (cultivated, grazing, coffee agroforestry, and forest lands) identified in the study area. The land suitability assessment, using the maximum limitation method, study was conducted on four soil mapping units identified in the sub-watershed. Results indicate that total organic carbon stock (soil, litter plus live vegetation) in the sub-watershed ranged from 138.95 ton ha-1 in the crop land to 496.26 ton ha-1 in the natural forest. The soil organic carbon stock was found to be relatively higher than that of the vegetation carbon stock in the natural forest and coffee agroforestry land uses. The results of suitability evaluation revealed that the maximum current and potential (after corrective xix
measures are taken) land suitability class for production of late-maturing sorghum (180-240 days cycle), maize (180-210 days crop cycle), finger millet (120 – 150 days cycle) and coffee in the sub-watershed is marginally suitable (S3c). The maximum current and potential land suitability for upland rice (120 days) is not suitable (N2c). The major permanent limiting factor is low mean temperature (14.6 C) of the growing period in the study area as compared to the optimum temperature required for optimum growth of the selected crops. The major soil and landscape limitations include steep slope, poor drainage of low-lying areas, shallow effective root zone in the upper slopes, low organic matter and available P for sorghum and maize, high pH for maize and wetness for coffee. In all the climate models and emission scenarios, minimum and maximum temperature increment is high during June-July-August-September (JJAS) compared with the other seasons. The modest rise in minimum temperature and the slight increment of maximum temperature during the crop growing seasons (February-March-April-May (FMAM) and JJAS will benefit late-maturing sorghum and maize production in the study area. For the same model, the projected biomass yield and organic carbon sequestration of the two crop varieties varied with time slice and the type of emission scenario used. Generally, increasing biomass production and carbon sequestration were projected for Mid-century (MC) than Near-century (NC) for most of the models used. Late planting would increase sorghum biomass yield and the corresponding organic carbon as compared to early planting as projected by most of the models under both RCPs. Most models predicted an increase in maize biomass yield and organic carbon sequestration if supplementary irrigation is used. The results of this study indicate that the current land uses are not enhancing carbon sequestration because of their exploitative nature and the soil/landscape and climate are not optimum for production of the crops studied. The rise in temperature in the coming 50 years is expected to create a more favorable condition for production of late-maturing sorghum and maize varieties. In order to enhance carbon sequestration, soil productivity and crop yield, and reduce greenhouse gas emissions, the current land uses and their management require re-visiting. / College of Agriculture and Environmental Sciences / Ph. D. (Environmental Sciences)
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Geochemical impact of super-critical C02 injection into the St. Peter Sandstone Formation within the Illinois Basin : implication for storage capability in a carbon dioxide sequestrian systemThomas, Richard Michael January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Deep injection of waste CO2 and fluids from regional energy plants into the St. Peter Formation of the Illinois Basin, could effectively provide long term deep geologic storage. This research aims to explore the viability of this proposed injection. There are some basic criteria that must be met to effectively store waste in a geologic reservoir.
First, the reservoir must have sufficient porosity and permeability for both injectivity and for migration of the injected fluid through the reservoir. Second, the reservoir must be overlain by some form of impermeable seal or cap layer(s). Third, the reservoir should be sufficiently isolated from interaction with surface and near surface water. Finally, the formation must contain enough storage volume to handle significant amounts of injected material.
Massive sandstone formations that host large saline aquifers have the potential to serve as high capacity storage sites. Much of the research targeting the potential suitability and storage capacity attributes of these formations has been promising, but reproducibility of the results has been less than ideal. Some of this variability has been attributed to petrological differences in the sandstone reservoirs that are not readily evident when studying the target formation over a geographically significant area.
Based on the criteria, a promising candidate for injection and storage is the St. Peter Sandstone of the Illinois Basin. This study investigates the viability of liquefied CO2 storage within the St. Peter Sandstone on a micro scale.
Initial porosity and permeability of the formation plug samples ranged from 16% to 19% and 26 to 981 millidarcies (mD), respectively. The wide difference in permeability is attributed to variations in strength of the cement, in this case quartz overgrowth in the sandstone. This preliminary evidence indicates that the storage capacity of the formation will remain constant or increase depending on injection location, suggesting that the St. Peter Formation will lend itself well to future storage.
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Essays on location decisions and carbon sequestration strategies of U.S. firmsWu, Caiwen 01 February 2015 (has links)
Location is a critical component of business decisions. A firm's location decision may be influenced not only by market forces, such as the location of input suppliers, output processors and competitors, but also by government policies if such policies impact their expected profits and are applied non-uniformly across space. Likewise, a firm may adjust its business strategy, including opening and closing establishments and laying off employees as responses to changes in environmental regulations. In certain polluting industries, location decisions may include choosing potential storage sites for geologic carbon sequestration or finding landfills for industrial solid waste.
There is extensive literature discussing the effects of environmental regulations or agglomeration economies on firm location decisions but few studies analyze the interactive effect of environmental regulations and agglomeration economies across regions in the United States. The potential consequences of changes in environmental regulations may include loss of polluting establishments, jobs, and income. Geological carbon sequestration offers long term storage opportunities to mitigate greenhouse gases (GHGs). Incorporating environmental risk into economic assessments of geological
sequestration choices is crucial for finding optimal strategies in using alternative carbon storage sites with limited capacity. This dissertation consists of three essays that address the above issues.
The first essay examines the interactive effects of air quality regulation and agglomeration economies on polluting firms' location decisions in the United States. Newly available annual (1989-2006) county-level manufacturing plant location data for the United States on seven pollution intensive manufacturing industries are applied in the analysis. Conditional Poisson and negative binomial models are estimated, an efficient GMM estimator is also employed to control for endogenous regulatory and agglomeration variables. Results indicate that births of pollution intensive manufacturers are deterred by stricter environmental regulation; and are attracted by local agglomeration economies. County attainment/nonattainment designations can impose heterogeneous impacts over space and across industries. The magnitude of the regulatory effect depends on the level of local agglomeration. Urbanization economies offset the negative impacts of environmental regulation, whereas localization economies can reinforce or offset the negative impacts of environmental regulation, depending on the industry.
The second essay analyzes the effect of changes in regulatory environmental standards on the total stocks of establishments and local jobs and income Results indicate the effects vary across counties in the United States. When the standards were raised to 80 percent of the current level, from 2007 to 2009, the affected counties would lose a total of 326 establishments, 14,711 jobs with $705 million U.S. dollars of income each year. At the national economy level, the impacts of tightening environmental regulations are relatively small.
The third essay constructs a dynamic optimization framework that deals with optimal utilization of alternative nonrenewable resource sites (geological formations) with possible negative externalities. We apply the model to an optimal usage problem of alternative long term CO₂ geologic storage sites for carbon. The storage sites are different in terms of capacity and potential leakage after CO₂ injection; the problem is determining the minimum cost for storing a fixed amount of CO₂ (sequestered) within a
certain time period. Analytical solutions show the decision rule depends on the discount rate, storage capacities, marginal CO₂ storage costs, and environmental damage costs associated with CO₂ leakage from alternative sinks. The framework provides critical information about the optimal timing of switching from one resource sequestration site to another. / Graduation date: 2013 / Access restricted to the OSU Community at author's request from Feb. 1, 2013 - Feb. 1, 2015
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Preliminary Feasibility of Transporting and Geologically Sequestering Carbon Emissions in the Florida Pan-HandlePoiencot, Brandon Keith 01 January 2012 (has links)
According to the United States Department of Energy, fossil-fueled power plants account for 78% of stationary source CO2 emission in the United States and Canada. This has led electric utilities across the globe to research different alternatives for energy. Carbon sequestration has been identified as a bridge between fossil fuels and clean energy.
This thesis will present research results regarding the transportation costs of CO2 and the suitability of geology in the Florida Pan-Handle for sequestration infrastructure. The thesis will utilize various evaluation tools including GIS, numerical models, and optimization models.
Analysis performed for this thesis and review of published literature produced estimated carbon storage capacities for two areas in and near the Florida Pan-Handle. These areas were labeled Disposal Area 1 and Disposal Area 3. Disposal Area 1 was estimated to contain capacity for the storage of 5.58 gigatonnes of CO2. Disposal Area 3 was estimated to contain capacity for the storage of 2.02 gigatonnes of CO2. Transportation scenarios were analyzed over a 25 year period and the capacities above are sufficient to store the CO2 emissions from the Pan-Handle network of power plants for the study period.
Four transportation routing scenarios were investigated using transportation costs from the Poiencot and Brown CO2 pipeline capital cost model. The scenarios (models) consisted of the Right-Of-Way, Solo-Funded, Piece-Wise, and Authority models. Each presents a different method for the overall funding of the Florida Pan-Handle CO2 network and produced different total levelized and mean unit costs. The cheapest network on a mean unit cost basis was the network for Disposal Area 1 in the Authority Model, producing a mean unit cost of $0.64 per tonne of CO2.
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