Dissertationen zum Thema „Emission productivity“

Dry abrasive blasting is a commonly used surface preparation operation by many process industries to clean up metallic surfaces and achieve surface finishes suitable for future adhesion. Abrasives used in this process can be recyclable or expendable. This study was undertaken to evaluate the performance of three recyclable abrasives: garnet, barshot and steel grit/shot in terms of productivity (area cleaned per unit time), consumption (amount of abrasive used per unit area cleaned) and uncontrolled total particulate matter (TPM) emission factors (in terms of mass of pollutant emitted per unit area cleaned and mass of pollutant emitted per unit mass of abrasive consumed). Though there have been various attempts in the past to evaluate the performance of these abrasives, there has not been a streamlined approach to evaluate these parameters in the commonly used range of process conditions, or to identify and model the influences of key process variables on these performance parameters. The first step in this study was to evaluate the performance of these three abrasives in blasting painted steel panels under enclosed blasting conditions and using USEPA recommended protocols. The second step was to model the influences of blast pressure and abrasive feed rate, two most critical parameters on productivity, consumption and emission factors. Two and three dimensional models were obtained using multiple linear regression techniques to express productivity, consumption and TPM emission factors in terms of blast pressure and abrasive feed rate. Barshot was found to have high productivities over all and steel grit/shot demonstrated the least emission potential at almost all of the tested pressure and feed rate conditions. The data will help fill the gaps in literature currently available for dry abrasive blasting performance. The models obtained will help industries, the research community and the regulatory agencies to make accurate estimates of the performance parameters. Estimating productivity and consumption will help industries identify best management practices by optimizing the process conditions to achieve high productivity and low consumption rates. Emission factor determination will help in reducing the emissions to the atmosphere by choosing process conditions corresponding to minimum emissions. The performance parameters once optimized can result in reduction in material, labor, energy, emission and disposal costs, lower resource utilization and hence reduction in overall life cycle costs of dry abrasive process. The developed models will help industries in making environmentally preferable purchases thereby promoting source reduction options. PM emissions estimated using the models presented here will aid studies on health risk associated with inhalation of atmospheric PM.

Dry abrasive blasting is one of the most widely used methods of surface preparation. Air emissions from this process include particulate matter (PM) and metals. Spent abrasive generated from this process may be hazardous in nature. With increasing concern on health effects due to silica emissions from sand, use of alternative materials is suggested by health and regulatory agencies. The objective of this research was to evaluate performance of expendable abrasives and determine PM emission factors. Dry abrasive blasting was performed in an enclosed chamber and total PM samples were collected. Three commonly used expendable abrasives, coal slag, copper slag and specialty sand, were used to evaluate cleaner alternatives. Blast pressure and abrasive feed rate, two important process conditions were varied to study their effect on performance of an abrasive. Productivity, consumption and emission factors (performance parameters) were calculated and their variation with pressure and feed rate was evaluated. Two dimensional and three dimensional predicted models were developed to estimate the performance at intermediate blast pressure and feed rate conditions. Performance of the three abrasives was compared with respect to emission potential, productivity and consumption. Emission factors developed in this research will help in accurate estimation of total PM emissions and to select cleaner abrasives and optimum process conditions that will results in minimum emissions and reduced health risk. The productivity and consumption models will help is estimating life cycle costs including material cost, equipment cost, energy cost, labor costs, waste disposal cost, and compliance costs. Consumption models will also help in determining the quantity of spent abrasive generated, identify abrasives with lower material consumption, and identify process conditions that generate minimum spent abrasives. In addition, these models will help industries in making environmentally preferable purchasing (EPP), which results in pollution prevention and cost reduction.

In the struggle against climate change, policymakers are faced with the difficult problem of maintaining economic growth while trying to reduce emissions. This paper studies the effect of the carbon emission tax, EU ETS and energy taxes on Swedish industry productivity between 2009-2018 with the purpose of evaluating the Porter hypothesis. A two-step approaches is used. First, Malmquist indexes are calculated using DEA and analyzed on total factor productivity, efficiency change and technical change. These performance indicators are then regressed on policy variables using OLS with a first difference estimator. Contrary to the Porter hypothesis the evidence does not suggest any effect on productivity, but can induce technical change.

The main challenge of modern agriculture lies in the need of enhancing crop productivity to guarantee food security while achieving the sustainability of cropping systems in a changing climate. In a recent speech to the 21st Conference of Parties to the United Nations Framework Convention on Climate Change (COP21) held in Paris, the president of the United States declared that for all the challenges we face, the growing threat of climate change could define the contours of this century more dramatically than any other. This is why He hopes that all the countries in the world, united in common effort and by a common purpose, will not condemn the next generation to a planet that’s beyond its capacity to repair. Agricultural activities deep influence the carbon, water and nutrients cycles at global level, then still play a vital role in the survival of humankind. The need to double food production by 2050 is entrusted to agriculture, which accounts for 14% of greenhouse gases emission and is considered as the economic sector most uniquely susceptible to changes in climate patterns, due to its dependence on the biophysical environment. Standing first among all food grain crops, rice (Oryza sativa L.) is in the spotlight due to the projected decrease in production in top producing countries and to the environmental sustainability of rice cropping systems, in light of the use of large amount of water for irrigation and of the contribution to the emission of greenhouse gases (GHGs) at the global level. The improvement of the water and nutrient management in paddy rice cropping systems is then considered as a necessary step to mitigate agriculture’s GHG emissions, as reported by the United Nations Foundation. The scaling up of mitigation strategies from farmers’ level to national policy makers needs the support of the scientific community, who is in charge to develop research to address these paramount questions. In this framework, the adoption of cropping system simulation models as a reference to assess both the productivity and the environmental impacts of cropping systems under a variety of management and climatic scenarios seems unavoidable, as they are the only available tools to reproduce the nonlinear responses of biophysical processes to boundary conditions. They also represent a viable solution to design and test alternate strategies to mitigate the emission of GHGs and to optimize the use and management of resources in agriculture. This PhD program enables the scientific community to move forward the integration of available biophysical models to dynamically simulate the different components of the rice cropping system, considering the multiple, mutual interactions among system’s domains which determine rice crop yield and environmental drawbacks. The final achievement is the delivery of a software targeting this purpose, which is documented in the last chapter; the objective of this research product is to give a modelling solution to simulate the comprehensive set of biophysical processes involved with the paddy rice cropping system, considering the crop development and growth, the soil water dynamics, the effects of fertilizers on nitrogen leaching and the emission of greenhouse gases at field scale, considering the impact of alternate farmer management strategies. During the work some deficiencies in current models were highlighted and solved, such as the unjustified complexity of widely adopted crop simulators or the lack, within them, of algorithms for the simulation of processes which significantly contribute to explain the variability of rice yield. The output of this work is made available through software components and modular modelling solutions: this choice, representing the state of the art of software engineering science, removes technological bottlenecks which usually prevent advances in agricultural system modelling and fosters international collaborations between research centers while laying the basis for further developments.

Cette thèse examine comment les portefeuilles de produits influencent la productivité des émissions dans le secteur manufacturier, en remettant en question les cadres politiques qui visent à atteindre la décarbonation principalement par des gains d'efficacité. En exploitant des données d'entreprises du secteur manufacturier portugais (2004-2021), elle analyse l'hétérogénéité des intensités d'émission au sein des industries et évalue l'impact de la composition des produits sur la productivité des émissions à l'échelle des entreprises. En combinant des données administratives sur la consommation d'énergie, des bilans comptables et des ventes de produits, l'étude quantifie la mesure dans laquelle la diversité des portefeuilles de produits contribue aux écarts d'intensité d'émission.Les résultats montrent que les entreprises d'un même secteur présentent des écarts significatifs en matière de productivité des émissions, souvent plus marqués que ceux observés entre industries. L'analyse de décomposition de la variance confirme que cette hétérogénéité est largement expliquée par des facteurs propres aux entreprises plutôt que par des tendances sectorielles générales. La classification des produits en catégories à fortes et faibles émissions suggère que les entreprises dont la production est davantage orientée vers des biens à faibles émissions affichent une productivité des émissions plus élevée. Grâce à l'analyse de décomposition des indices et aux régressions sur données de panel, la thèse explore également l'évolution des intensités d'émission à l'échelle des entreprises. Les résultats indiquent que les réductions globales des émissions sont principalement associées à des gains d'efficacité, tandis que les entreprises qui ajustent leur portefeuille vers des produits à faibles émissions enregistrent des améliorations durables en matière de productivité des émissions.Ces résultats s'inscrivent dans le débat plus large sur les stratégies de décarbonation en soulignant l'importance des portefeuilles de produits en complément des améliorations d'efficacité. Si les avancées technologiques jouent un rôle clé, cette étude souligne que les stratégies de décarbonation axées uniquement sur l'amélioration de l'efficience risquent de négliger l'impact structurel de la composition de la production. Les conclusions soulèvent également des questions sur les cadres réglementaires actuels et la manière dont ils favorisent ou limitent l'orientation vers des produits à faibles émissions. En s'appuyant sur les perspectives de l'économie écologique et de la planification démocratique, cette thèse éclaire la question de savoir si les ajustements impulsés par le marché suffisent ou si des interventions réglementaires supplémentaires sont nécessaires pour faciliter des changements structurels dans la production industrielle
This thesis examines how product portfolios shape emission productivity within the manufacturing sector, questioning policy frameworks that aim to achieve decarbonization primarily through efficiency increases. Using firm-level data from the Portuguese manufacturing sector (2004-2021), it explores heterogeneity in emission intensities within narrowly defined industries and assesses the impact of product composition on firm-level emission productivity. By integrating administrative records on energy consumption, financial data, and product-level sales, the study quantifies the extent to which variations in product portfolios contribute to differences in emission intensity.The findings reveal that firms within the same industry exhibit substantial variation in emission productivity, often exceeding inter-industry differences. Variance decomposition analysis confirms that a significant share of this heterogeneity is explained by firm-level factors rather than sector-wide characteristics. A classification of products into high- and low-emission categories indicates that firms producing a greater share of low-emission goods tend to have systematically higher emission productivity. Through index decomposition analysis and firm-level panel regressions, the study further examines whether adjustments in product portfolios influence firm-level emission intensities over time. The results suggest that aggregate emission reductions have been largely driven by efficiency gains, yet firms that transition toward lower-emission products show sustained improvements in emission productivity.These findings contribute to debates on industrial decarbonization by emphasizing the role of product portfolios alongside efficiency improvements. While technological advancements play a key role, the study highlights how decarbonization strategies that focus solely on efficiency gains may overlook the structural impact of production composition. The results also raise policy questions regarding the extent to which regulatory frameworks encourage or constrain shifts toward lower-emission products. By engaging with perspectives from ecological economics and democratic planning, this thesis offers insights into whether market-driven adjustments alone are sufficient or whether additional regulatory measures are needed to facilitate structural changes in industrial production

Meat and milk from sub Saharan African cattle systems tend to have high greenhouse gas emissions intensities; this is largely due to low levels of productivity. There is a need to increase production to meet an increasing demand for livestock commodities; driven by growing populations, and growing diet variation, as incomes and urbanisation increase. Without measures to reduce the emissions intensity of production, there will be significant increases in total greenhouse gas emissions. Therefore, cost-effective ways of reducing emissions intensity, whilst increasing productivity should be identified. This thesis looks to support this by providing an assessment of low-input to semi-intensified cattle production systems in Senegal, West Africa; where cattle populations are growing and efforts are being made to increase domestic milk production. The emissions intensity of protein from current production systems is calculated using a version of the Food and Agriculture Organization’s Global Livestock Environmental Assessment Model (GLEAM). Variation in emissions intensity is observed between current systems, which can be largely linked to feed ration quality and levels of protein productivity. Productivity improving interventions suitable for the study systems are identified, and their application to current systems modelled by altering input parameters within GLEAM. It is suggested that production systems could reduce emissions intensities by applying nutritional and health related intervention packages; through which the varying production systems could abate between 10% and 20% of their total greenhouse gas emissions whilst also making financial savings. A comparison between the current systems of production also suggests that changing the lower productivity systems to match higher producing systems would also offer substantial cost-saving emissions abatement. The thesis considers the key limitation to the use of GLEAM for modelling the application of nutritional mitigation measures, in that when nutritional improvements are made animal performance does not currently increase. Predicting how animals will respond to improved nutrition is challenging. However, a methodology is discussed, and is shown to have an important effect on the emissions abatement results. Subsequently, the thesis advocates further research to experimentally substantiate animal performance responses when nutritionally limited cattle are given improved feed regimes. Despite the study livestock keepers showing aspiration to improve the productivity of their herds, with subsequent potential to reduce greenhouse gas emissions, the thesis recognises that the abatement potentials suggested by modelling would be restricted by the reality of production system context and constraints. Key barriers to a realisation of the productivity improvements include: a lack of financial means, limitations to resource access and affordability, and requirement for information and training concerning productivity improving options. For realisation of productivity improvements the current barriers would require further investigation, the thesis helps identify what form interventions should take.

Air pollution is a threat to the environment and human health. Freight trucking in particular is the main source of freight transportation emissions. Heavy-duty trucks emit large amounts of toxic air pollutants that cause serious diseases and harm public health. In addition, heavy-duty trucks emit great amounts of greenhouse gas (GHG), which is the leading cause of global warming. Despite increased environmental restrictions on air pollution and rising trucking greenhouse gas emissions in the past decades, no economic study has examined the potential GHG and air pollution reductions in the trucking sector and the associated private abatement costs to the industry. This study accounts for GHG emissions and toxic air pollutants in measuring and evaluating efficiency and productivity for the trucking industry in the 48 contiguous states. Moreover, the private costs of abatement to the industry were also estimated. When only GHG was incorporated in the production model, the results showed that each state could expand desirable output and reduce GHG by an average of 11 percent per year between 2000 and 2007. The Malmquist-Luenberger productivity indexes showed that omitting or ignoring GHG in trucking service production yielded biased estimates. On the other hand, due to increased environmental regulations, most of the toxic air pollutants decreased dramatically between 2002 and 2005. The analytical results showed that inefficiency decreased during this period. The private costs of abatement averaged $73 million per state in 2005. When GHG and six toxic air pollutants were incorporated in the production model, the estimated private abatement cost was $76 million per state, which was equivalent to 0.7 percent of the industry output in 2005.

This thesis is a multiyear study in Sri Lanka to evaluate the impact of using urban derived compost in combination with synthetic N fertiliser on nitrogen use efficiency, greenhouse gas emissions, and productivity from tropical cropping systems. The study demonstrated the high potential for N losses in low CEC tropical soils. However, the high relative cost of OA compared to synthetic N fertilisers requires substantial additional benefits above the value of the nutrients alone to make their use economical.

Pasture-based systems are important milk suppliers to dairy industry and thereby will play relevant role to support the growing demand for food. However, this additional milk supply must be obtained through higher yields resulting from intensification of existing farming systems through strategies environmentally friendly and economically profitable towards sustainable intensification. The central hypothesis of this study was that simple grazing management strategies can improve the efficiency while reduce the key environmental issues of tropical pasture-based dairy systems. Two experiments were carried out on a rainfed and non-irrigated elephant grass (Pennisetum purpureum Schum. cv. Cameroon) pasture in Piracicaba, SP, Brazil. The objective of the first experiment was to investigate the influence of two pre-grazing targets (95% and maximum canopy light interception during pasture regrowth; LI95% and LIMAX, respectively) on sward structure and herbage nutritive value, dry matter intake (DMI), milk yield, stocking rate, enteric methane (CH4) emissions by Holstein × Jersey dairy cows, and nitrous oxide fluxes from the soil. Results indicated that pre-grazing canopy height was greater for LIMAX (≈135 cm) than LI95% (≈100 cm) and can be used as a reliable field guide for monitoring sward structure. Grazing management based on the LI95% target improved herbage nutritive value and grazing efficiency, allowing greater DMI, milk yield and stocking rate by dairy cows. Daily enteric CH4 emission was not affected; however, cows grazing elephant grass at LI95% were more efficient and emitted 21% less CH4/kg of milk yield and 18% less CH4/kg of DMI. The 51% increase in milk yield per hectare overcame the 29% increase in enteric CH4 emissions per hectare for the LI95% target. Nitrous oxide fluxes were not affected by pre-grazing targets. Overall, strategic grazing management is an environmentally friendly practice that improves the use efficiency of allocated resources through optimization of processes involving plant, ruminant and their interface, and enhances milk production efficiency of tropical pasture-based systems. Once the ideal pre-grazing target was established during he first experiment (LI95%), the second step consisted of a refinement of the first phase. The second objective was to describe and measure the influence of two timings of new paddock allocation to cows (AM and PM) on herbage chemical composition and DMI, milk yield, milk compostion, and enteric CH4 emissions of Holstein × Jersey dairy cows. Results supported the general understanding of diurnal variation in herbage chemical composition towards greater concentrations of dry matter and non-fibrous carbohydrates, and lower concentration of fiber components in the afternoon herbage. However, the higher nutritive value of the afternoon herbage did not result in increasead DMI and milk yield, or decreased intensity of CH4 emission by dairy cows. Our findings also indicate that new paddock allocation in the afternoon can be a simple and useful grazing strategy that results in greater N partitioning to protein yield, and lower excretion of urea N in milk. The association of LI95% pre-grazing target and PM allocation could bring economic, productive and environmental benefits towards sustainable intensification of tropical pasture-based systems.
Sistemas baseados no uso de pastagens são importantes fornecedores de leite para a indústria de latícinios e, dessa forma, terão papel relevante para suportar a crescente demanda por alimentos. No entanto, essa oferta adicional de leite deve ser obtida através de maiores produtividades resultantes da intensificação de sistemas de produção já existentes por meio de estratégias ambientalmente seguras e economicamente rentáveis em direção à intensificação sustentável. A hipótese central deste estudo foi que estratégias simples de manejo do pastejo podem melhorar a eficiência e, ao mesmo tempo, reduzir os principais impactos ambientais dos sistemas de produção animal em pastagens tropicais. Foram realizados dois experimentos em pastagem de capim-elefante (Pennisetum purpureum Schum. Cv. Cameroon) não-irrigada em Piracicaba, SP, Brasil. O objetivo do primeiro experimento foi avaliar a influência de duas metas pré-pastejo (95% e máxima interceptação de luz pelo dossel durante a rebrotação; IL95% e ILMáx, respectivamente) sobre a estrutura do pasto e valor nutritivo da forragem, consumo de matéria seca (CMS), produção de leite, taxa de lotação, emissões de metano entérico (CH4) de vacas HPB × Jersey, e o fluxo de óxido nitroso dos solos. Os resultados indicaram que a altura pré-pastejo foi maior para ILMáx (≈135 cm) do que IL95% (≈100 cm) e pode ser usada como um guia de campo confiável para monitorar a estrutura do pasto. O manejo do pastejo com base nos critérios de IL95% melhorou o valor nutritivo da forragem e a eficiência de pastejo, permitindo maior CMS, produção de leite e taxa de lotação. A emissão diária de CH4 entérico não foi afetada; no entanto, as vacas que pastejaram o capim-elefante manejado por IL95% foram mais eficientes e emitiram 21% menos CH4/kg de leite e 18% menos CH4/kg de MS consumida. O aumento de 51% na produção de leite por hectare superou o aumento de 29% nas emissões de CH4 entérico por hectare para a meta IL95%. Os fluxos de óxido nitroso não foram afetados pelas metas pré-pastejo. De maneira geral, o manejo do pastejo com base na meta IL95% é uma prática ambientalmente segura que melhora a eficiência de uso dos recursos alocados por meio da otimização de processos envolvendo plantas, ruminantes e sua interface, e aumenta a eficiência da produção de leite em sistemas baseados em pastagens tropicais. Uma vez que a meta pré-pastejo ideal foi estabelecida durante o primeiro experimento (IL95%), a segunda etapa consistiu-se em um refinamento da primeira. O segundo objetivo foi descrever e medir a influência de dois horários de alocação de novos piquetes aos animais (AM e PM) sobre a composição química da forragem, CMS, produção e composição do leite, e emissões de CH4 entérico de vacas HPB × Jersey. Os resultados confirmaram a compreensão geral da variação diurna na composição química da forragem em direção a maiores concentrações de matéria seca e de carboidratos não-fibrosos, e menor concentração de componentes da fibra na forragem amostrada pela à tarde. No entanto, o maior valor nutritivo da forragem da tarde não aumentou o CMS e a produção de leite, nem diminuiu a intensidade de emissão de CH4 das vacas leiteiras. Os resultados também indicaram que a alocação à tarde pode ser uma estratégia de manejo simples e útil que resulta em maior partição de N para produção de proteína, e menor excreção de N ureico no leite. A associação da meta pré-pastejo IL95% e a alocação do rebanho para um novo piquete à tarde poderia trazer benefícios econômicos, produtivos e ambientais para a intensificação sustentável de sistemas baseados em pastagens tropicais.

Over the last few decades, production processes have become increasingly fragmented: they are divided into ever smaller parts considered as separate activities, which are then spread over various locations in different countries. In other words, value chains for many products are becoming global. This implies that inputs into the production process are sourced from both local and foreign suppliers. The latter mode of sourcing is commonly referred to as offshoring. Expressed as the share of imported in total intermediates, offshoring has grown relatively fast in the recent past. Moreover, its scope has been extended as it increasingly encompasses not only manufacturing but also service activities. A typical example for the former is the sourcing from abroad of parts and components for car assembly. While offshoring of manufacturing activities has been occurring since long and has been largely facilitated by trade liberalisation, the offshoring of service activities such as the provision of accounting or call centre services is a more recent phenomenon that has been fostered by the increased tradability of such services.

With the increasing scale and scope of offshoring, it becomes crucial to get a grasp of its drivers as well as the gains and threats associated with it. The latter are the focal point of the public and academic discussion around offshoring, in particular the potential threats for workers in developed economies. Typical questions that are being raised are whether offshoring leads to job losses in developed countries and whether it favours certain categories of workers and is to the disadvantage of others. These threats are directly linked to the motivations for engaging into offshoring. In this respect, wage costs play a prominent role. But other factors may also influence offshoring decisions, e.g. regulations, in particular those regarding the environment. Last but not least, offshoring may also entail gains for developed economies through the improvements in the efficiency of production. In this PhD thesis, several causes and consequences of offshoring are examined empirically for Belgium.

The first issue that is investigated is whether offshoring of materials and business services affects industry-level employment. An improved offshoring intensity measure is introduced. It is a volume measure of the share of imported intermediates in output split into materials and business services and according to the country of origin of imports, i.e. high-wage and low-wage countries. Estimations of static and dynamic industry-level labour demand equations augmented by offshoring intensities do not reveal a significant impact of either materials or business services offshoring on total employment for Belgium. This result holds for both the manufacturing sector and the service sector and it proves robust to splitting the manufacturing sector into high-technology and low-technology industries.

These results raise the question whether there are actually productivity gains from offshoring. Therefore, estimates of the impact of materials and business services offshoring on industry-level productivity in Belgium are presented. Two features of the analysis are new compared to the existing literature on this subject: the issue is examined separately for manufacturing and market services industries and the possibility of forward and backward spillovers from offshoring, i.e. that productivity gains from offshoring feed through to upstream and downstream industries, is investigated. Results show that materials offshoring has no effect on productivity, while business services offshoring leads to productivity gains in manufacturing. Furthermore, there is no evidence of either forward or backward spillovers from offshoring.

Despite the absence of an industry-level total employment effect, offshoring may alter the within-industry composition of employment. In this respect, a major concern is the worsening of the labour market position of low-skilled workers. This issue is addressed by providing evidence on the impact of offshoring on the skill structure of manufacturing employment in Belgium between 1995 and 2007. Offshoring is found to significantly lower the employment share of low-skilled workers. Its contribution to the fall in the employment share of low-skilled workers amounts to 35%. This is mainly driven by offshoring to Central and Eastern European countries. Business services offshoring also contributes significantly to the fall in the low-skilled employment share. As a complement to the existing literature, the widely used current price measure of offshoring is compared with a constant price measure that is based on a deflation with separate price indices for domestic output and imports. This reveals that the former underestimate the extent of offshoring and its impact on low-skilled employment. Finally, further results show that the impact of offshoring on low-skilled employment is significantly smaller in industries with a higher ICT capital intensity.

Furthermore, attention is drawn to environmental effects of offshoring by asking whether offshoring contributes to reducing air emissions from manufacturing. Indeed, since the mid-90’s, production-related air emissions in Belgian manufacturing have been reduced substantially. It can be shown that the pace of the reduction has been fastest for domestic intermediates. The issue of whether offshoring has played a role in this reduction by replacing domestic intermediates by imported intermediates is widely debated. Here, a decomposition analysis is developed to measure the contribution of offshoring – the share of imported intermediates in total intermediates – to the fall in air emissions for domestic intermediates. Based on the results from this decomposition analysis, it is possible to calculate that 17% of the fall in greenhouse gas emissions, 6% of the fall in acidifying emissions and 7% of the fall in tropospheric precursor emissions in Belgian manufacturing between 1995 and 2007 can be attributed to offshoring.

Finally, emission intensities are also considered as a potential determinant of offshoring. An econometric approach for testing the pollution haven effect for imported intermediate materials is developed. The approach is new with respect to the existing literature on pollution havens through its specific focus on imports of intermediates. The test is embedded in a cost function framework from which a system of cost share equations for variable input factors is derived. The set of potential determinants of the demand for imported intermediate materials includes emission intensities for three types of air pollutants. Their impact constitutes a test of the pollution haven effect. The system of cost share equations is estimated by a within ISUR using data for the Belgian manufacturing sector. Results show some albeit relatively weak evidence of a pollution haven effect for imported intermediate materials.

Doctorat en Sciences économiques et de gestion
info:eu-repo/semantics/nonPublished

Aligning competitiveness with climate change mitigation objectives lies at the heart of contemporary discourses on sustainable development, resource efficiency, green growth, and the circular economy. While numerous scholars and policymakers, particularly in Europe, follow the notion that decreasing material use and increasing material productivity can boost competitiveness and help to mitigate climate change, the empirical evidence underlying this assertion has put little emphasis on two important issues. First, many studies predominantly rely on case studies, often not considering dynamic effects and heterogeneity across firms, sectors, countries, material subgroups, and material indicators. Second, the majority of investigations do not address the potential problem of endogeneity in empirical models. This dissertation attempts to shift the focus on these and other issues having received relatively little scrutiny in the existing literature by four interrelated analyses on European economies and firms. First, the effect of material use on greenhouse gas (GHG) emissions is empirically assessed, finding a robust and positive link mostly driven by fossil fuel use. Second, it is investigated whether economic growth is a driver of material use, suggesting that economic growth causes an increase in material use for Western European countries. Third, the effects of material productivity on indicators of macroeconomic competitiveness and GHG emissions are investigated, finding little evidence for any statically significant link, except of increased average wages and improvements in the current account. Fourth, the effects of eco-innovation induced material productivity increases on microeconomic competitiveness and firm level GHG emissions are studied, providing evidence that material productivity increases microeconomic competitiveness and reduces GHG emissions. However, these effects are heterogeneously distributed across sectors and countries. Overall, this dissertation draws a nuanced picture by providing new evidence that material use and material productivity can support competitiveness and climate change mitigation objectives, but such benefits are likely to be unequally distributed across firms, sectors, and countries. To this end, the results provide important policy insights, including that weight-based material indicators are linked to GHG emissions, internalising externalities is essential, and eco-innovations can enable certain firms, sectors, and countries to grasp the benefits of material productivity improvements. Moreover, it is important to further investigate the implications of moving towards more material productive economies based on greater emphasis on heterogeneity, endogeneity, and improved data.

Au cours de ces dernières années, la croissance des investissements mondiaux dans les énergies renouvelables a été rapide. En effet, les énergies renouvelables (ER) sont considérées comme une alternative pour faire face au réchauffement climatique, à la raréfaction des ressources naturelles, à l’augmentation de la demande énergétique, à la volatilité des prix de l’énergie fossile et à la répartition inégale des sources énergétiques. Nous nous proposons dans cette thèse de mener une analyse visant à approfondir les réflexions sur l’investissement dans les ER (IER). Le premier objectif consiste à évaluer le retour sur l’IER. Nous avons choisi d’évaluer théoriquement et empiriquement l’impact de l’IER sur les émissions des Gaz à Effet de Serre (GES) et sur la Productivité Totale des Facteurs (PTF). Le deuxième objectif de cette thèse vise à évaluer l’impact des instruments de soutien au développement des ER (ISER) sur l’IER. Dans le premier chapitre, nous avons montré comment la relation entre les IER et les émissions de CO2 n’est pas linéaire, mais qu’elle prend la forme d’une courbe en U inversé. En d’autres termes, les IER ont un effet positif sur les émissions de CO2 jusqu'à ce que ces investissements atteignent un niveau donné, ou un certain seuil, au-delà duquel, les IER auront un impact négatif sur les émissions de CO2. Cette relation a été testé empiriquement en utilisant la régression en panel à transition brutale (PTR : Panel Threshold Regression model). Le deuxième chapitre de la thèse explore la relation entre l’investissement en énergie renouvelable (IER) et la productivité. En nous référant à la théorie de la croissance endogène, nous avons testé empiriquement notre hypothèse principale qui stipule que l’IER affecte positivement la croissance de la Productivité Totale des Facteurs. L’étude empirique a été réalisée sur un panel de 43 pays développés et en développement, à l’aide de la méthodologie de GMM-système. Au regard des résultats obtenus, cette étude a permis de confirmer notre hypothèse. En effet l’impact positif des IER sur la croissance de la PTF s’explique par le fait que l’IER encourage le transfert technologique et occasionne d'importantes retombées de connaissances (« knowledge spillover »). L’objectif du troisième chapitre consiste à discuter le rôle et l’impact des Instruments de Soutien au développement des ER (ISER) sur l’IER. Nous nous intéressons précisément à l’efficacité des ISER pour attirer les investissements en nouvelles capacité de production d’électricité à partir de sources d’énergie renouvelable. Nous pouvons déduire de notre étude que l’amélioration des IER passe généralement par les instruments de marché, et non pas par les instruments de commande et de contrôle, à l’exception des pays à faible revenu. D’ailleurs, une combinaison entre les instruments du « Market-pull » et du « Market-push » permet de soutenir les IER. Nous remarquons aussi que le soutien des IER passe par les instruments qui affectent indirectement ces investissements. En effet, pour encourager les IER, il vaut mieux agir en amont, en incitant la recherche, de développement et de déploiement (RDD) dans le secteur des ER, et en aval, en stimulant la production d’électricité renouvelable, à travers les tarifs d’achat garanti (les « Feed-in-Tariffs» )
Recently, growth in global investments in renewable energy (IRE) has been so rapid. In fact, renewable energy (RE) is considered as an alternative to deal with global warming, with the scarcity of natural resources, with the increase in energy demand, with the volatility of fossil fuel prices and with the unequal distribution of energy sources. This study attempts to shed more light on the IRE. The study’s prime goal is to evaluate the return on the IRE. It analyses theoretically and empirically the impact of the IRE on the greenhouse gas (GHG) emissions and on Total Factor Productivity (TFP). The study’s second goal is to evaluate the effectiveness of the policies that support the development of RE. The first chapter showed how the relationship between IREs and CO2 emissions is not linear, but, rather, it follows an inverted U-shaped curve. In other words, IREs have a positive impact on CO2 emissions until the investments reach a certain level, beyond which the IREs impact on CO2 emissions becomes negative. The current study has analyzed this relationship empirically by means of the panel threshold regression (PTR) model. The second chapter explores the relationship between IRE and productivity. Referring to the theory of endogenous growth, the study empirically tested the main hypothesis, that IRE positively affects the TFP growth. The empirical study was conducted on a panel of 43 developed and developing countries, using the GMM-system methodology. Study’s findings confirm that IRE have a positive affect on the Total Factor Productivity growth. Indeed, this positive impact is theoretically explained by the fact that the IRE encourages technology transfer and it generates significant knowledge spillovers. The third chapter of the thesis discusses the role and the impact of the policies that encourage the development of RE on IRE. Specifically, in this chapter we evaluate the effectiveness of these policies to attract renewable energy investments in electricity-generating capacity. The results show that the market instruments increase the IREs, although command or control instruments have no or a negative effect, with the exception of low-income countries. Moreover, a combination of "market-pull" and "market-push" instruments can supports the IREs. We also note that IRE support goes through the instruments that indirectly affect these investments. Indeed, to encourage IREs, it is better to act upstream, by spurring research, development and deployment (RDD) in the RE sector, and downstream, by stimulating the production of renewable electricity, through Guaranteed Purchase Rates or Feed-in-Tariffs (FIT)

Energia é um insumo estratégico na mineração, pois é fundamental na viabilidade das operações mineiras e importante na manutenção de custos operacionais baixos e competitivos. Por esse motivo, toda iniciativa que visa a busca por eficiência no consumo de energia é importante para a competitividade das mineradoras. Vários insumos energéticos são utilizados nas operações unitárias de mineração. Os exemplos mais comuns são diesel, eletricidade, gás natural, carvão e explosivos. O objetivo desse trabalho é estudar, do ponto de vista energético, as atividades realizadas no processo de desmonte de rochas, em um complexo minerador de minério de ferro, visando a melhor utilização da energia no desmonte de rocha para aperfeiçoar as operações unitárias subsequentes de processamento de minérios. Um foco maior foi dado à economia de energia nas moagens de bolas da planta de beneficiamento e concentração, provocada pelas modificações e melhorias realizadas no desmonte de rocha. A metodologia consistiu na análise de diversos desmontes de rocha variando a razão de carga de explosivos no complexo minerador alvo desse trabalho. Os produtos desses desmontes foram acompanhados até a sua entrada na planta de beneficiamento. Durante o processamento desses materiais nas moagens da planta, foram coletadas e analisadas as grandezas elétricas resultantes e comparadas com uma linha de base gerada antes do início do trabalho. Os dados foram analisados com o objetivo de visualizar a influência do aumento da razão de carga na performance energética da operação de moagem. Em paralelo, também, foram analisadas as situações operacionais e dificuldades existentes nas medições de campo e nos acompanhamentos de consumos energéticos dos processos unitários, assim como a infraestrutura necessária para que uma variável tão importante como energia elétrica possa ser monitorada de forma adequada. Por fim, foi abordada a importância, a metodologia e os resultados da redução de emissões de CO2 provenientes da economia de energia de todo o trabalho realizado em campo. Os resultados apresentados mostram que mesmo com um aumento significativo da alimentação de material compacto (maior WI) nas moagens, o consumo energético total dessa operação unitária não aumentou. Isso gerou uma potencial economia específica de energia e a consequente redução de emissões de CO2 na atmosfera, além de viabilizar o processamento de material mais compacto nas mesmas linhas de processo. Esse comportamento sugere que uma melhor energia gasta no desmonte de rocha pode impactar positivamente na produtividade e nos custos de produção do minério ao longo de sua cadeia produtiva.
Energy is a mining strategic source, critical in mining operations feasibility and important to maintain low operational costs in a competitive level. For this reason, any initiative aimed at searching for energy efficiency is important for mining companies’ competitiveness. Mining operations need several energy sources. Most common examples are diesel, electricity, natural gas, coal and explosives. This text aims to address, from an energy perspective, a study carried out in an iron ore mining complex, which had as main objective to reach a better rock blasting energy utilization to improve subsequent mining operations. A greater focus was given to energy savings in ball mills operations of a beneficiation and concentration plant, impacted by modifications and improvements made in rock blasting. Methodology consisted in monitoring several rock blasting, carried out in this mining complex, varying explosive charge ratio. Products of those rock blasting were monitored until they entered the processing plant. During ore processing in plant´s ball mills, electrical variables were collected and analyzed, comparing to a baseline generated before the beginning of this research. All data were analyzed to show influence of explosive charge ratio increase on energy performance of the milling operation. In parallel, operational issues and difficulties in field measurements of energy consumptions were described, as well as the necessary infrastructure that allows the variable electricity to be adequately monitored. Besides, the methodology and results of CO2 emissions reduction from energy savings of all fieldwork were discussed. The research data shows that even with a significant increase in compact feed (higher Work Index), total energy consumption of mill operation did not increase. This scenario generate a potential specific energy savings and consequent reduction in CO2 emissions in the atmosphere. In addition, enables more compact material to be processed in the same process lines. This behavior suggests that a better energy spent on rock blasting can positively affect productivity and ore production costs along its production chain.

O reúso da água é uma prática amplamente estudada e recomendada por diversos pesquisadores como alternativa viável para suprir as necessidades hídricas e, parte das demandas nutricionais das plantas. No Brasil, esta atividade está em processo de desenvolvimento. Sua implantação está condicionada a especificidades locais, respeitando as legislações dos recursos hídricos, proteção ao meio ambiente e saúde pública. Além de fatores como qualidade do efluente tratado e seleção de culturas a serem irrigadas, faz-se necessário aplicar práticas adequadas de manejo, para conservação das propriedades físico-químicas e biológicas do sistema solo, planta e atmosfera. Diante do exposto, o presente trabalho teve como objetivo a avaliação do comportamento dos íons na solução do solo e no solo, do fluxo de gases do efeito estufa e da produtividade da água da cultura, em um sistema de produção irrigado com efluente de abatedouro tratado por sistema anaeróbio, no cultivo de capim coastcross para feno, em diferentes doses de adubação nitrogenada. O delineamento experimental adotado foi em blocos ao acaso, com cinco tratamentos e quatro repetições, sendo estes: T1 - irrigação com água superficial e adição de 100% de adubação nitrogenada (AN) recomendada; T2, T3, T4 e T5 - irrigação com efluente tratado de abatedouro e adição de 0; 33%; 66% e 100 % de AN, respectivamente. Sendo a AN 50 kg ha-1 corte-1 de nitrogênio, na forma de ureia. O solo foi avaliado quimicamente nas profundidades de 0-0,20 m e 0,20-0,40 m, para os parâmetros de fertilidade e sódio trocável. A solução do solo foi obtida por pasta de saturação para posterior análise dos íons Na+, Mg2+, Ca2+, K+, SO4-, NO2-, NO3- e NH4+. A produtividade da água foi determinada pela relação entre produção de massa seca do capim e lâmina de irrigação mais precipitação pluviométrica. A coleta de gases do solo foi realizada por câmaras estáticas e os gases analisados foram gás carbônico, metano e óxido nitroso, por cromatografia gasosa, para determinação do fluxo de gases do solo. Os dados foram avaliados nas estações inverno-primavera (ano 2017) e verão-outono (ano 2018). Os resultados comprovam o potencial do uso de efluentes tratados de abatedouro na irrigação do capim coastcross, como forma complementar ao tratamento anaeróbio. O manejo adotado concentrou os elementos químicos do solo na camada 0-0,20 m, profundidade efetiva do sistema radicular do capim. O aporte de sais ao solo ocorreu nos tratamentos com efluente, no período inverno-primavera, as precipitações ocorridas no período seguinte (verão) foram suficientes para lixiviar os sais para a camada inferior do solo. A análise de solução do solo comprovou o potencial de lixiviação de nitrogênio na forma de nitrato e nitrito, durante todo o período estudado, principalmente para o tratamento com efluente tratado de abatedouro e 100% da AN. Os tratamentos não influenciaram a produtividade da água. A avaliação do fluxo de gases de efeito estufa do solo comprovou a influência das variáveis climáticas e da umidade do solo, ao longo do tempo. O fluxo de CO2 foi maior na coleta de dezembro/2017, incrementado nos tratamentos com efluente. Considerando a dinâmica de solutos no solo, o potencial do aporte de nutrientes e o teor salino do efluente, assim como o fluxo de gases de efeito estufa do solo, o tratamento com efluente tratado de abatedouro, sem adubação nitrogenada, foi o tratamento mais adequado para as condições de desenvolvido do experimento.
Water reuse is a practice widely studied and recommended by several researchers as a viable alternative to meet water needs and part of the nutritional demands of plants. In Brazil, this activity is in the process of development. Its implementation is conditioned to local specificities, respecting the laws of water resources, protection of the environment and public health. In addition to factors such as the quality of the treated effluent and the selection of crops to be irrigated, it is necessary to apply appropriate management practices for the conservation of the physical-chemical and biological properties of the soil, plant and atmosphere system. In view of the above, the present work had the objective of evaluating the behavior of the ions in soil and soil solution, the greenhouse gas flow and the crop water productivity, in an irrigated production system with treated slaughterhouse effluent by anaerobic system, in the cultivation of coastcross grass for hay, at different doses of nitrogen fertilization. The experimental design was a randomized complete block design, with five treatments and four replications: T1 - irrigation with superficial water and addition of 100% of recommended nitrogen fertilization (AN); T2, T3, T4 and T5 - irrigation with treated effluent from slaughterhouse and addition of 0; 33%; 66% and 100% AN, respectively. Being the AN 50 kg ha-1 cut-1 of nitrogen, in the form of urea. The soil was chemically evaluated at depths of 0-0,20 m and 0,20-0,40 m, for fertility and exchangeable sodium parameters. The solution of the soil was obtained by saturation paste for later analysis of Na+, Mg2+, Ca2+, K+, SO4-, NO2-, NO3- and NH4+ ions. The water productivity was determined by the relation between dry mass production of the grass and irrigation blade plus rainfall. Soil gas collection was performed by static chambers and the gases analyzed were carbon dioxide, methane and nitrous oxides, all by gas chromatography, to determine the flow of soil gases. The data were evaluated in the seasons winter-spring (2017) and summer-autumn (2018). The results confirm the potential of the use of treated effluents from slaughterhouse on coastcross grass irrigation as a complementary form to the anaerobic treatment. The management adopted concentrated the chemical elements of the soil in the layer 0-0,20 m, effective depth of the grass root system. The contribution of salts in the soil occurred in the treatments with effluent, in the winter-spring period, the precipitations occurred in the following period (summer) were sufficient to leach the salts to the lower layer of the soil. The soil solution analysis showed the potential of nitrogen leaching in the form of nitrate and nitrite, during the whole studied period, mainly for treatment with slaughterhouse treated effluent and 100% AN. Treatments did not influence water productivity. The evaluation of the flow of greenhouse gases from the soil proved the influence of climatic variables and soil moisture over time. The CO2 flux was higher in the collection of December / 2017, increased in the treatments with effluent. Considering the dynamics of solutes in the soil, the nutrient supply potential and the saline content of the effluent, as well as the greenhouse gas flow of the soil, treatment with treated effluent from slaughterhouse, without nitrogen fertilization, was the most appropriate treatment for the developed conditions of the experiment.

The Tasmanian sawmilling industry typically does not season eucalypt material specifically for furniture applications because of its highly refractory seasoning characteristics. Boards cut with wide faces parallel to the growth rings ('backsawn or 'flatsawn' boards), in particular, shrink significantly with drying and often experience surface checking (seasoning 'degrade'). It is standard practice to season timber batches under schedules designed to produce relatively high-grade structural material and sell the small proportion of boards that do not suffer seasoning degrade as furniture grade material. The aim of this study was to investigate optimum seasoning of backsawn material specifically for furniture applications to take advantage of the premium prices paid by furniture manufacturers for degrade-free material. Acoustic emission is a well known non-destructive testing tool. Acoustic emission results from stress waves generated by irreversible stress release activity such as the growth of small cracks in a solid material under load. Acoustic emission is typically used in homogeneous materials such as plastics and metals to determine the structural integrity of components in situ. Acoustic emission was first measured in timber subject to external load over thirty years ago and has subsequently been measured in drying timber specimens where differential drying rates between the surface and centre of a sample may cause appreciable drying stresses. Acoustic emission appeared to be related to the severity of the drying conditions and the development of surface checking (Becker 1982, Noguchi et al. 1987). Under harsh drying regimes, surface checking occurred and a significantly higher AE rate was measured than in the same species subject to mild drying conditions. The 'AE rate' is a measure of the occurrence of high-energy bursts of acoustic waves during a particular time-period - the higher the AE rate, the more energetic bursts are measured. On this basis, it appeared feasible to measure acoustic emission in sample boards in a kiln during drying and adjust the drying conditions as the AE rate approached levels previously determined to correspond to surface checking. Various AE-based kiln control systems were reported in the literature (Honeycutt et al. 1985, Noguchi et al. 1987) but it appears acoustic emission was not satisfactorily related to surface check development. These control systems controlled the drying conditions based on arbitrary AE rates that were nominally selected as 'safe' without optimising the drying process. The heterogeneous structure of timber posed significant obstacles to forming a clear picture of the stress release processes occurring in timber. Acoustic emission measured in drying Tasmanian eucalypt boards was employed in this project as an online measure of the magnitude of the stresses during drying. Numerous batches of eucalypt boards were obtained from a sawmill during the project and dried under harsh conditions to induce surface checking. It was determined that the AE rate generated at the onset of surface checking in backsawn and quartersawn boards was effectively constant (within the variability of the material). This 'AE checking threshold' was independent of basic density and clearly independent of bulk stiffness (since the bulk tangential stiffness is effectively half the radial stiffness in the species studied). It appeared that the acoustic emission phenomenon was independent of the timber bulk material properties. It is proposed that acoustic emission waves propagate from irreversible slips or dislocations in the crystalline cellulose regions of cell walls under high stress. These slips are sudden, energetic stress release events which propagate stress waves from the local site. The amorphous regions of the cell structure behave in a rather plastic manner with local stress expected to be consumed by ductile flow processes that do not generate elastic waves. Dinwoodie (1968) reported the existence of such crystalline slips in spruce timber under external compression. Siau (1984) reported that the proportion by mass of cellulose in normal wood (as opposed to tension and compression wood) was remarkably constant and apparently independent of species. Further, the proportion of crystalline cellulose is also relatively constant (Siau 1984). This appears to be directly related to the remarkably constant AE rate measured at the onset of surface checking in this study. This finding led to the measurement of acoustic emission in other species. It was hoped that the same AE 'rate would be measured at the onset of checking in different woods. Acoustic emission was measured in backsawn radiata pine (Pinus radiata) and myrtle (Nothofagus cunninghamii). The acoustic emission measured in radiata pine was significantly different from the acoustic emission measured in the eucalypt material, with relatively 'massive' AE rates detected in boards free of seasoning degrade. This behaviour was attributed to brittle failure in the resin canals, structural elements not present in the eucalypt genus. The characteristic AE responses measured in drying myrtle boards resembled the behaviour measured in the eucalypt boards, apparently due to the more similar structure. Surface checking was detected at approximately the same AE rate as that measured in the eucalypt boards. Much of the improved understanding of the acoustic emission phenomenon developed in this study was facilitated by the existence of a one-dimensional nonlinear drying model developed by Oliver (1991). Oliver wrote KILNSCHED (KILN SCHEDULING PROGRAM), a computer program based on this model, which simulates the drying behaviour of a single board, with arbitrary bulk material properties, subject to arbitrary drying conditions. KILNSCHED is particularly suited to low temperature drying of eucalypt materials. Kiln drying trials quickly revealed that 'green' Tasmanian eucalypt boards invariably suffered surface checking within 24 hours when subject to drying temperatures as low as 23°C dry bulb temperature and 21°C wet bulb temperature (at 0.5 m/s airspeed). Such temperatures are significantly lower than those often employed in drying material direct off-saw in the timber industry but none-the-less are considered 'harsh' in this study. At the commencement of this study, KILNSCHED was used in a purely predictive mode to assess drying schedules prior to drying. The author of this thesis modified KILNSCHED to simulate drying using the real-time drying temperatures measured in the experimental kiln. This allowed measured acoustic emission during drying to be compared with the drying behaviour calculated with KILNSCHED. This modification revealed that Tasmanian eucalypt timber is far more sensitive to small temperature fluctuations than was previously expected. The reader must keep this material sensitivity to temperature and temperature change in mind at all times when reading this thesis. The AE rate measured during drying was successfully related to the instantaneous strain at a board surface calculated with KILNSCHED using the measured drying conditions. Instantaneous strain is the strain component employed as the failure criterion in the drying model. This enabled the author to place considerable confidence in behaviour calculated with KILNSCHED and the 'optimum drying' program SMARTKILN discussed below. This author modified KILNSCHED to incorporate an optimisation algorithm that determined the optimum drying conditions required to dry the timber in the minimum time at a preset arbritrary maximum surface instantaneous strain. The resulting program, SMARTKILN, develops drying schedules to maintain the calculated surface instantaneous strain at a preset 'Control Strain' below the ultimate surface instantaneous strain. Together, SMARTKILN and acoustic emission measurement form the basis of Clever Kiln Controller®, a kiln control system to dry Tasmanian eucalypt timber in the minimum time with minimum degrade. In Clever Kiln Controller, SMARTKILN uses datalogged real time drying conditions to simulate the drying behaviour of a sample board in the kiln. Calculated drying behaviour is continuously compared with measured drying behaviour (measured AE rate and moisture profiles measured by regularly slicing sample boards). Provided the calculated and measured drying behaviour are satisfactorily matched, the optimum drying schedule developed by SMARTKILN is applied to the kiln. When the AE rate approaches the AE checking threshold, the drying conditions are automatically ameliorated to prevent surface checking. Subsequently, SMARTKILN develops a refined optimum schedule to incorporate the new datalogged drying conditions. This study has developed the understanding of acoustic emission from the existing (often misleading) information recorded in the literature to a level that could be incorporated with current knowledge of the behaviour of drying timber. The thesis describes how this was achieved. Various aspects of the understanding have been reported in papers published, in press or under review. The final result is the development of a commercial kiln controller which is described and already implemented in some selected experimental kilns at present restricted to eucalypt materials.

碩士
國立屏東科技大學
土壤與水工程國際碩士學位學程
106
Decreasing water input and Carbone Dioxide (CO2) emissions while maintaining grain yield remain a challenge for World to produce rice sustainably. In recent years, the Alternate Wetting and Drying technology (AWD) has been developed toward Asian’ farmers. However, the gap observed is the lack of assessment of its performances, particularly in Taiwan. The aim of this study is to determine whether the AWD regime, when applied on System of Rice Intensification (SRI), could maintain grain yield with reduced water input and mitigation of CO2 gases. SRI approach experiment field was conducted in National Pingtung University, Southern Taiwan. A rice seedling, TAINAN 11 (TN11) was arranged in a randomized complete block design with five water treatments: SRI2cm, SRI3cm, SRI3cm/w, SRI4cm and SRI5cm with respectively 2cm and 3 cm water depth monitoring by soil airlines cracks; 3cm, 4 cm and 5cm weekly irrigation. The irrigation regimes were done by AWD technics. The plant water status was assessed through the leaf water potential and the CO2 emission monitored at 7-day intervals. Crop growth, grain yield and water productivity were measured. The results showed that grain yields under SRI3cm, SRI2cm and SRI3cm/w presented the high yield; SRI4cm and SRI5cm despite the high-water depth presented low yield with respectively 3080 Kg/ha and 2604 Kg/ha. The CO2 emission under SRI3cm was lowest than SRI3cm/w and SRI2cm. SRI4 and SRI5cm presented the same range of CO2 emission with 319 ppm. A negative correlation was observed between CO2 and LAI. The results confirmed also that SRI3cm and SRI3cm/w could obtain comparable grain yield close to farmers practices with fewer irrigations. These findings suggested that the SRI with 3 cm water depth (SRI3cm and SRI3cm/w) could be used for water-saving and greenhouse gases mitigation while maintaining grain yield in SRI production.

Thesis (MSc. (Animal Production)) -- University of Limpopo, 2018
A study was done to determine the effect of Acacia (A.) karroo, A. tortilis or A. nilotica leaf meal inclusion in a diet on methane emission and productivity of yearling male Boer goats fed a basal diet of Avena sativa hay. The first part of the study was conducted to determine and compare nutrient contents and tannin levels of A. karroo, A. tortilis and A. nilotica leaf meals and Avena sativa hay in a completely randomised design. The diets means were compared using Fisher’s least significant difference at the 5 % level of probability. The three Acacia species had higher (P<0.05) crude protein contents compared to Avena sativa hay, ranging from 12.42 to 14.49 %. No tannins were detected in Avena sativa hay. Among Acacia species, A. nilotica leaves had higher (P<0.05) total phenolic and total tannin contents than A. karroo and A. tortilis leaves, the latter being similar (P>0.05). All three Acacia species had similar (P>0.05) contents of condensed tannins, ranging from 1.49 to 1.76 %. However, only A. nilotica leaves had hydrolysable tannins of 128 mg/g. The second part of the study was conducted to determine the effect of A. karroo, A. tortilis or A. nilotica leaf meal inclusion level on diet intake and digestibility, methane emission, productivity and blood profiles of yearling male Boer goats. A total of three experiments were conducted and different goats were used in each experiment. A grand total of thirty six (twelve per experiment) yearling male Boer goats with initial mean live weights of 23 ± 2 kg (experiment 1), 23 ± 2 kg (experiment 2) and 23 ± 2 kg (experiment 3) were used in 21-day experiments. The goats were randomly assigned to four dietary treatments, each containing A. karroo, A. tortilis or A. nilotica leaf meal inclusion levels at 10, 15, 20 and 30 % with Avena sativa hay as a basal diet. Each goat was housed in well-ventilated individual metabolic pen. The diets were replicated three times. The data collected were subjected to analysis of covariance and analysis of variance in a completely randomized design using SAS. Differences were separated at 5 % level of probability. Additionally, regression equations were used to determine the relationships and responses in optimal diet intake and digestibility, methane emission, productivity and blood profiles of yearling male Boer goats to differing inclusion levels of A. karroo, A. tortilis and A. nilotica leaf meal. v Experiment 1 involved feeding different levels of A. karroo leaf meal inclusion to yearling male Boer goats fed Avena sativa hay as a basal diet. Results of methane emission before and during the experiment indicated that inclusion of A. karroo leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and after experiment were affected (P<0.05) by inclusion of A. karroo leaf meal. However, A. karroo leaf meal inclusion level had no effect (P>0.05) on diet intake, methane emission, live weight changes and digestibility, except (P<0.05) for digestibility of crude fibre. Feed conversion ratio improved linearly with increased A. karroo leaf meal inclusion level. In the case of experiment 2, results of methane emission before and during the experiment indicated that inclusion of A. tortilis leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and after the experiment were affected (P<0.05) by inclusion of A. tortilis leaf meal. However, variation in A. tortilis leaf meal inclusion level had comparable effect (P>0.05) on methane emission, live weight changes and digestibility, except (P<0.05) for digestibility of crude protein and acid detergent fibre. Diet intake and feed conversion ratio were affected (P<0.05) by A. tortilis leaf meal inclusion level. A positive relationship was observed between A. tortilis leaf meal inclusion level and diet intake. In experiment 3, results of methane emission before and during the experiment indicated that inclusion of A. nilotica leaf meal in the diets of goats reduced (P<0.05) methane emission. Similarly, some of the blood parameters before and the after experiment were affected (P<0.05) by inclusion of A. nilotica leaf meal. Apart from diet fat digestibility and feed conversion ratio, no statistical differences (P>0.05) were observed on diet intake, digestibility and live weight changes of goats fed A. nilotica leaf meal inclusion level. Positive relationships were observed between A. nilotica leaf meal inclusion level, diet fat digestibility and feed conversion ratio in male Boer goats. The high crude protein and low tannin contents in A. karroo, A. tortilis and A. nilotica leaves indicate that these Acacia species can be safe to use as a source of protein in animal nutrition if used sparingly. It was noted that nutrient intake, digestibility, vi feed conversion ratio and blood profiles of Boer goats in the present study were optimised at different inclusion levels for all the three Acacia species. This may imply that inclusion levels of A. karroo, A. tortilis and A. nilotica leaf meals for optimal productivity will depend on the Acacia species used and, also, on particular productivity parameters in question. Although, A. karroo, A. tortilis and A. nilotica leaf meal reduced methane emission, optimal reduction in methane emission was not determined. Further validation is required to determine Acacia inclusion levels for optimal methane production and emission by goats.
NRF (National Research Foundation), AGRISETA (Agricultural Sector and Education Training Authority) and NSFAS (National Students Financial Aid Scheme)

Climate crisis is one of the biggest problems that humanity is facing, and the solution seems to be far away from being reached, since there are other problems that depend on the economic performance of the countries that need also to be addressed by governments. For this reason, solutions must be studied in line with both objectives relating to economic activity and environmental protection. Eco-innovation can be one of those solutions and, therefore, it has been attracting the attention of researchers. This study intends to make a contribution to this theme. To understand the impact of Eco-innovation, two variables are used, namely, a ratio with GDP/Energy and another with GDP/Emissions. These variables will allow understanding the impact of Eco-innovation on Energy and CO2 Emissions productivity. Using a panel data and an ARDL model, this relationship is explored, both in the short and in the long term, allowing controlling for the Cross-sectional Dependence, a problem that arises due to the high dependency between the countries of the EU, which constitute the sample of our study. The results do not suggest a long-term relationship between Eco-innovation and GDP/Energy and GDP/Emissions. The same is verified for GDP/Emissions in the short term, though a very small-scale negative effect was found for GDP/Energy. The results suggest that it is possible to maintain the same level of GDP using Eco-innovation, at least for Energy consumption in EU countries.
A crise climática é um dos maiores problemas que a humanidade está a enfrentar e a solução parece estar longe de ser alcançada, já que, outros problemas, dependentes do desempenho económico dos países, também prendem a atenção dos governos. Por esta razão, devem ser estudadas soluções em consonância com os objetivos relativos à atividade económica e de proteção ambiental. A Eco-inovação poderá ser uma dessas soluções e, por isso, tem vindo a atrair a atenção de investigadores. Este estudo pretende, então, dar um contributo acerca deste tema. Para compreender o impacto da Eco inovação, são utilizadas duas variáveis, nomeadamente, um rácio com PIB/Energia e outro com PIB/Emissões. Estas variáveis permitem entender o impacto da Eco-inovação na produtividade energética e de emissões. Utilizando dados em painel e um modelo ARDL, esta relação é explorada, tanto no curto como no longo prazo, permitindo controlar a Dependência Transversal, problema que decorre devido à elevada dependência entre os países da União Europeia, que constituem a amostra do nosso estudo. Os resultados não sugerem relação de longo prazo entre Eco-inovação e PIB/Energia e PIB/Emissões. O mesmo se verifica no curto prazo em relação à variável PIB/Emissões, embora tenha sido encontrado um efeito negativo de muito pequena escala em relação ao PIB/Energia. Os resultados obtidos sugerem que é possível manter o mesmo nível de PIB utilizando a Eco-inovação, pelo menos para o consumo energético em países da UE.

Streszczenie Naturalne, niezaburzone antropogenicznie torfowiska pełnią niezwykle istotne funkcje. Są to, jedne z największych globalnych magazynów węgla, a w skali zlewni stanowią ważne miejsce retencji pierwiastków biogennych. Typowe dla torfowisk stałe wysokie uwodnienie oraz wycofywanie z obiegu pierwiastków biogennych wywołują w zbiorowisku roślinnym stresy anoksji oraz niskiej żyzności. Czynniki te ograniczają produkcję pierwotną i zwiększają szanse przetrwana na torfowiskach gatunków roślin słabych konkurencyjnie, często zagrożonych. Równocześnie torfowiska należą dziś do ekosystemów najszybciej degradujących się za sprawą działalności człowieka. W wyniku osuszenia powierzchniowe warstwy torfu ulegają mineralizacji, co powoduje emisję węgla do atmosfery oraz eutrofizację wód powierzchniowych. Ponadto na skutek zaniku czynników stresowych silnie konkurencyjne gatunki wypierają słabsze gatunki wyspecjalizowane. Aby ograniczyć negatywne skutki degradacji torfowisk rozpoczęto realizację projektów restytucji przyrodniczej tych ekosystemów. Początkowo metodą stosowaną w tych zabiegach było podniesienie poziomu wody poprzez zablokowanie rowów odwadniających. Metodę tą krytykowano jednak za jej negatywny wpływ na efekt cieplarniany (okresowe znaczne zwiększanie emisji metanu) oraz z powodu wzrostu żyzności (następującego równocześnie ze zwiększeniem uwilgotnienia), który uniemożliwia odtworzenie populacji rzadkich gatunków torfowiskowych. Drugą rzadziej stosowaną w restytucji torfowisk niskich metodą jest usuwanie wierzchniej, zdegradowanej warstwy torfu. Skuteczność tej metody w odtwarzaniu zbiorowisk roślinnych typowych dla torfowisk niskich została dobrze udokumentowana. Jednak do dziś nie wiadomo, jak metoda ta wpływa na relatywną dostępność poszczególnych pierwiastków biogennych, co może mieć duże znaczenie dla rozwoju fitocenoz. Co więcej, wiedza o wpływie tej metody na odtworzenie usług ekosystemowych torfowisk, takich jak wpływ na bilans gazów cieplarnianych czy obieg pierwiastków w zlewni, jest skąpa i oparta na pośrednim wnioskowaniu. Celem niniejszej rozprawy doktorskiej była ocena skuteczności restytucji torfowiska niskiego metodą usuwania zdegradowanej warstwy gleby w zakresie jej wpływu na: (1) warunki wzrostu roślin; (2) przywrócenie usług ekosystemowych związanych z obiegiem pierwiastków; (3) efekt cieplarniany, oraz porównanie tej metody z metodą powtórnego nawodnienia zdegradowanego torfowiska. Terenem badań było torfowisko Bagno Całowanie, na którym realizowany był projekt restytucji przyrodniczej, obejmujący m. in. usunięcie warstwy zdegradowanego torfu z powierzchni ok. 2 ha. Badania prowadziłem na tym obszarze oraz na zlokalizowanych wokół niego powierzchniach kontrolnych (zdegradowane, przesuszone partie torfowiska), referencyjnych (refugia roślinności nawiązującej do mechowisk zlokalizowane w obszarach dawnego wydobycia torfu) oraz poletkach eksperymentalnych, na których imitowano restytucję metodą powtórnego nawodnienia. Uzyskane przeze mnie wyniki wskazują, że metoda usuwania warstwy zdegradowanego torfu, w odróżnieniu od metody powtórnego nawodnienia zdegradowanego torfowiska, pozwala ograniczyć stężenia pierwiastków biogennych w roztworze glebowym oraz nie wywołuje zwiększenia emisji metanu. Z drugiej strony okazało się, że zastosowanie tej metody nie doprowadziło do odtworzenia warunków siedliskowych charakteryzujących się zasobnością w kationy metali zbliżoną do ekosystemów referencyjnych. Ponadto, względna dostępność fosforu w stosunku do azotu nie została ograniczona w stopniu wystarczającym, by odtworzyć warunki, w których produkcja pierwotna byłaby limitowana niedoborem tego pierwiastka (co sprzyjałoby zagrożonym gatunkom roślin). Ponadto, gdy w analizie wpływu na efekt cieplarniany uwzględniłem także efekt mineralizacji usuniętej zdegradowanej warstwy torfu, metoda usuwania warstwy zdegradowanej okazała się mniej korzystna dla klimatu (wskutek emisji dwutlenku węgla do atmosfery) niż metoda powtórnego nawodnienia. Pomimo wykazanych w pracy wad usuwania warstwy zdegradowanego torfu, ta metoda może zostać uznana za bardziej efektywną pod względem odtwarzania usług ekosystemowych oraz warunków występowania słabych konkurencyjnie gatunków roślin od powtórnego nawodnienia w ogólnym porównaniu obydwu metod. Ograniczenie stężeń azotanów i fosforanów sprzyja odtworzeniu niskoproduktywnych ekosystemów torfowiskowych. Ponadto w następstwie restytucji ograniczony zostaje ładunek azotu trafiający do zlewni, w której znajduje się torfowisko, a ilość dopływającego do niej fosforu pozostaje bez zmian. Problem wpływu dwutlenku węgla z mineralizującego się, usuniętego zdegradowanego torfu, na efekt cieplarniany może zaś zostać rozwiązany, jeśli torf ten zostanie wykorzystany w rolnictwie, leśnictwie lub ogrodnictwie jako substytut torfu wydobytego z niezaburzonych hydrologicznie torfowisk. W ten sposób emisje gazów cieplarnianych wywołane przez działania restytucji zostaną skompensowane przez ograniczenie emisji na innym obszarze.

Reclamation success is highly dependent upon final soil quality of stockpiled soils, such as those found Cold Lake Oil Sands Region. Stockpiled soils, however, are generally poor in quality. Soils were amended with, biochar (BC), humalite (HU), a sub-bituminous coal; and peat (PT), as well as 50:50 blends of biochar:humalite (BCH) and biochar:peat (BCP). These amendments were applied at rates of 0, 6.55, 13.1 and 26.2 g C kg-1 each. Biochar, PT, and BCP applied at the rate of 26.2 g C kg-1 were found to reduce N2O emissions by 34, 54, and 70%, respectively, relative to the control. Within the bioassay, BC and PT amendment resulted in a 38 and 40% increase in dry matter yield (DMY) respectively. Finally, amendment typically resulted in significant net decreases in Olsen P values, while nitrate and ammonium concentrations were high in PT amended soils. In general, PT had the best overall performance.
October 2015

This research analyzes fuel consumption and emissions of Turnpike double trailer combinations (Turnpikes) on a regional network in the Canadian Prairies. The research: (1) establishes current benchmarks for fuel consumption of Turnpikes and five-axle tractor semitrailers (3-S2s) with van trailers; (2) develops fuel consumption models for these vehicle types; (3) establishes an understanding of current operating characteristics of Turnpikes in the region; and (4) estimates their system-wide effects in terms of fuel consumption and emissions in Manitoba by applying the developed models. Canadian Prairie region-based carriers revealed an increase in Turnpike travel (from 2007-2009) of 44 percent after the twinning of the Trans-Canada Highway between Winnipeg and Regina in 2007 was completed. Turnpikes can save one third of fuel consumed when compared to 3-S2s; have higher fuel consumption in the winter months; and their use in 2009 reduced fuel consumption and CO2 emissions by five percent compared to 3-S2s.

This thesis examines the performance, challenges and prospects of the Chinese coal industry under transformation in the market transition period from 1993 to date. The term 'transformation' is used intentionally to distinguish it from 'transition', which is more commonly used. While issues arising from state-ownership are central in an economic transition, the tenn 'transformation' also takes into account the existence of China's other specific challenges including the many small scale mines, poor mining safety, and pressure on the industry's prospects resulting from increasingly stringent environmental regulations. ... Based on the results of empirical and quantitative analysis, several policy recommendations are proposed which include deepening market reforms of State-owned coal mines through privatisation or relinquishment of state ownership, changes of corporation governance and debt restructuring; and improving governance of small coal mining through improvement of the legal and fiscal frameworks and building of SCM's capacity. The participation of stakeholders is useful in the process of improving safety and regularising small coal mining. The formulation of industrial policies such as participating in the unemployment insurance system, promoting export liberalisation, strengthening mining consolidation, are also recommended. The thesis also argues that the policy of simply closing down mines in China is impractical and ineffective, and that a better alternative is to govern their development through regularisation. The thesis also outlines some directions for future research into the coal industry's transformation.
Rio Tinto-ANU China Partnership, ANU-PKU exchange program, Vice-Chancellor's travel grant