Die vorrangige Zielstellung dieser Dissertation war die Berechnung nicht erschlossener landwirtschaftlicher Potenziale des Europäischen Russlands. Wir haben ein räumliches Allokationsmodell entwickelt, dass die jährlichen Acker- und Ackerbrachflächen von 1991 bis 2009 kartiert. Diese Daten haben wir anschließend in ein dynamisches Vegetationsmodell integriert und damit berechnet, dass während der postsowjetischen Aufgabe von 31 Millionen Hektar Ackerland bis 2009 470 TgC in Boden und Vegetation gebunden wurden. Anschließend haben wir ein Pflanzenwachstumsmodell auf regionale Weizenerträge kalibriert und darauf basierend durchschnittliche Ertragslücken von 1.51-2.10 t ha−1 für natürliche (künstlich unbewässerte) und 3.14-3.30 t ha−1 für künstlich bewässerte Anbaubedingungen ermittelt. Die Karte der Ackerbrachflächen, räumlich-explizite Informationen über die Kohlenstoffspeicherung in Boden und Vegetation infolge der Ackerflächenaufgabe sowie unsere Ergebnisse der Ertragslückenberechnung haben wir zur Berechnung von Weizenproduktionspotenzialen verwendet. Unsere Ergebnisse zeigen, dass das Europäische Russland erhebliche Potenziale mobilisieren kann – bis zu 32 Millionen Tonnen für künstlich unbewässerte Bedingungen – obwohl ausschließlich jüngere Ackerbrachen zur Rekultivierung in unserem Modell berücksichtigt wurden. Ältere Brachflächen haben häufig große Mengen Kohlenstoff in Boden und Vegetation gespeichert; die Rekultivierung ältere Brachflächen würde zu hohen Emissionen führen. Eine wesentliche Schlussfolgerung dieser Dissertation ist daher, dass Produktionssteigerungen vorrangig durch Flächenintensivierung der bestehenden Ackerflächen erzielt werden sollten. Allerdings können die Ergebnisse dieser Arbeit helfen, Brachen für die Rekultivierung zu bestimmen, deren Rekultivierung relativ geringe Kohlenstoffemissionen nach sich ziehten. Zudem können die Ergebnisse dieser Arbeit nützlich sein, landwirtschaftliche Produktionsmittel effizienter einzusetzen. / This dissertation addresses the primary objective to systematically quantify untapped agricultural potentials in European Russia, where widespread abandoned agricultural lands and large yield gaps co-exist. We developed a spatial allocation model to produce annual cropland and cropland abandonment maps. Feeding the new maps into a dynamic vegetation model revealed that 470 Tg of carbon was sequestered in soil and vegetation due to the abandonment of 31 million hectares of cropland. Thus, the environmental consequences limit the potential for cropland expansion to abandoned cropland. We then calibrated a crop growth model for provincial wheat yields in European Russia and found average yield gaps of 1.51–2.10 t ha−1 under rainfed conditions and 3.14–3.30 t ha−1 under irrigated conditions. The cropland abandonment maps, spatial information on carbon sequestration due to cropland abandonment, and the estimates of yield gaps allowed us to estimate the potential of European Russia to increase its wheat production and to account for the carbon tradeoffs of cropland expansion. We demonstrated that European Russia can substantially increase its wheat production (up to 32 Mt under rainfed conditions). This increase is despite a limited expansion of wheat cultivation to the recently abandoned cropland to reduce the trade-off from the high carbon emissions in re-cultivating older, abandoned cropland where most carbon is stored. Therefore, intensification of the existing croplands is recommended to be the major driver for future growth in agricultural production. This dissertation can help policy makers and agribusiness owners identify areas suitable for cropland expansion, better target agricultural inputs and infrastructures, as well as guide adaptation strategies to the volatile climate conditions. Moreover, this dissertation contributes to better identifying and balancing trade-offs between environmental impacts and increasing agricultural production in European Russia.

A atividade humana tem contribuído com as emissões de gases de efeito estufa (GEE) associadas, principalmente, com queima de combustíveis fósseis e mudanças no uso da terra. Assim, se faz necessário que sejam adotadas medidas visando o retardamento dos efeitos das mudanças climáticas. As florestas exercem papel essencial no balanço de carbono principalmente por funcionarem como sumidouros de CO2. Por outro lado, se desmatadas, promovem emissões e liberam parte do carbono estocado. A quantidade de biomassa florestal e o teor de carbono podem variar em função do tipo florestal, bem como de sua localização. Entretanto, fator importante diz respeito à confiabilidade dos dados mensurados neste tipo de pesquisa. A biomassa e o carbono da parte aérea podem ser determinados via método destrutivo, ou estimados via método não destrutivo. A construção do Rodoanel Mário Covas trecho norte e a supressão de uma área de Mata Atlântica possibilitou a realização de estudo de biomassa da parte aérea via método destrutivo. O objetivo deste trabalho foi estudar o tamanho e forma de parcelas, a intensidade amostral, quantificar a biomassa e o carbono na parte aérea, comparar métodos destrutivos e não destrutivos para a quantificação de biomassa e carbono na parte aérea, estudar a variação da densidade básica da madeira das espécies nas diferentes classes de DAP e grupos sucessionais e comparar as medidas de altura total e DAP obtidas a campo no inventário com as medidas coletadas após o corte. O tamanho mais conveniente de parcela foi 400 m 2, com forma retangular e dimensão de 10 x 40 m. A intensidade amostral variou entre 39 e 75 unidades amostrais. A biomassa da parte aérea obtida, via método destrutivo, foi de 188,3 Mg ha-1 e o carbono, 85,1 Mg ha-1. A biomassa estimada por equações alométricas da literatura foi subestimada, quando comparada ao valor real, obtido via método destrutivo. As menores classes de DAP apresentaram as maiores densidades básicas da madeira. A densidade básica foi 0,488 g cm-3 na média das espécies. A porcentagem de carbono contida nos troncos e galhos não diferiu entre as classes de DAP. O teor de carbono foi 45,41%, na média dos troncos e galhos. Espécies pioneiras acumularam maior quantidade de biomassa e carbono nos galhos e apresentaram maior densidade básica que as não pioneiras. A utilização dos dados coletados na fase de inventário e após o corte não afetaram os valores de biomassa estimados. / Human activity has contributed to the emission of greenhouse gases associated mainly with burning fossil fuels and changes in land use. Thus, it is necessary that measures be adopted to delay the effects of climate change. Forests play an essential role in the carbon balance mainly acting as CO2 sinks. On the other hand, if they are deforested, they will promote emissions and release some of the stocked carbon. The amount of forest biomass and the carbon content may vary depending on the forest type and its location. However, an important factor is about the reliability of the data measured in this type of research. Aboveground biomass and carbon can be determined via destructive method or estimated by non-destructive method. The construction of the north extension of Mário Covas Road and the suppression of an Atlantic forest area made it possible to carry out study of the aboveground biomass via destructive method. The goal of this work was to study the size and shape of plots, the sampling intensity, their aboveground biomass and carbon, compare destructive and non-destructive methods for the quantification of biomass and carbon, study the variation of wood basic density in the species in different classes of diameter of trunk at breast height (DBH) and successional groups and compare the total height and DBH measures obtained on field in the inventory with the measures taken after the cut. The most convenient plot size is 400 m2, with rectangular shape and size of 10 x 40 m. The sampling intensity varied between 39 and 75 sample units. The aboveground biomass obtained, via destructive method, was 188.3 Mg ha-1 and carbon, 85.1 Mg ha-1. The biomass estimated by allometric equations of the literature was underestimated compared to the real value obtained via destructive method. Smaller DBH classes had the highest wood basic density. The basic density was 0.488 g cm-3 in average of the species. The percentage of carbon contained in the trunks and branches did not differ between the DBH classes. The carbon content was 45.41%, in the average of the trunks and branches. Pioneer species accumulated higher amount of biomass and carbon in the branches and had a higher wood basic density than non pioneers species. The utilization of data collected in the inventory phase and after the cut did not affect the estimated biomass values.

Made available in DSpace on 2017-07-25T19:29:43Z (GMT). No. of bitstreams: 1 Ademir Oliveira Ferreira.pdf: 1294842 bytes, checksum: 8d7036f6aefa0cf3c549b0c63029e109 (MD5) Previous issue date: 2009-07-13 / Decrease in soil organic carbon (SOC) content of the surface layer into deeper layers indicates the occurrence of the stratification in the profile due to continuous C addition of crop residues enriching the soil surface layer. The objective of this study was: in Chapter 3 the relationship of stratification (RE) of C of the soil organic matter (SOM) pools can be an indicator of C sequestration in no-tillage soils? In the chapter 4 the tensile strength of aggregates is affected by the C content of Pedosequence of Latosol with medium and clay texture? in Chapter 5 which is the C balance and the amount of crop residue needed to maintain a stable C balance in a Latosol with a medium and clay texture? The experimental design was a completely randomized 2x2x2 factorial with 12 treatments. Treatments consisted of: a) an Oxisol (Red Latosol) with medium and clayey texture, b) two soil sampling periods (T1 and T2) with one year interval between them, and c) two soil sampling depths (0-5 and 5-20 cm). The soil attributes assessed were: the separation of water stable aggregates classes (19-8, 8-4, 4-2, 2-1, 1-0,5 and 05-0,25 mm), particulate organic carbon (POC), total particulate nitrogen (TPN) in the aggregate classes. Also was determined total organic carbon (TOC) and total nitrogen (NT) in the whole sample and in the aggregates sizes classes and tensile strength of aggregates. The relationship of stratification was calculated by dividing the TOC and TN values of 0-5 cm layer by the values of the same attributes of 5-20 cm layer. The C sequestration rate and the stratification ratio changes were calculated by the difference between the T2 values minus T1. The tensile strength was measured in soil aggregates and assessed in 1920 aggregates for each sampling time. Also TOC and NT content were measured in aggregates. The aggregates greater than 8 mm represented more than 70 of the total mass in both the clay and in sandy soil. The relationship of stratification ratio (0-5:5-20 cm) of SOC, TN, POC and TPN soil indicated the improvement of the surface layer. A significant linear relationship between the SR and C sequestration rate in both textural classes showed an increase in C sequestration and was more evident in LV with medium texture. The increase in TOC content resulted in decreased tensile strength (TS) of the aggregates and was more evident in the 0-5 cm layer. The TS showed inverse relationship with the soil density and was higher in the LV medium texture. The rate of sequestration of C was 0.86 for the LV with medium texture and 0.76 Mg ha-1 for the clay texture and to maintain the stable balance of C is required an input of 8.6 Mg ha-1 of crop residues. The results presented confirm the hypothesis of SR to be a sensitive indicator for the rate of carbon sequestration in no-tillage soil. Key-words: Carbon stock, Carbon balance, Carbon sequestration, Soil management systems, particulate organic carbon, particulate nitrogen. / A redução no conteúdo de carbono (C) da camada superficial em direção as camadas mais profundas do solo indica a formação da estratificação no perfil devido à adição contínua de C pelos resíduos orgânicos resultando no enriquecendo a camada superficial do solo. O objetivo deste trabalho foi avaliar os seguintes assuntos: a) a relação de estratificação (RE) de C dos compartimentos da matéria orgânica do solo (MOS) pode ser um indicador do seqüestro de C no sistema plantio direto. b) a resistência tênsil dos gregados pode ser afetada pelo conteúdo de C em Pedossequencia de Latossolo com textura média e argilosa. c) o balanço de C e a quantidade de resíduos culturais necessária para manter o equilíbrio estável de C em um Latossolo com textura média e argilosa. O delineamento experimental foi um fatorial 2x2x2 inteiramente casualizado com 12 tratamentos. Os tratamentos constituíram-se de: a) um Latossolo Vermelho com textura média e argilosa, duas épocas de amostragem do solo (E1 e E2) com um ano de intervalo entre si e duas profundidades de amostragem (0-5 e 5-20 cm). Os atributos avaliados foram: a separação das classes de agregados do tamisamento úmido (19-8, 8-4, 4-2, 2-1, 1-0,5 e 05-0,25 mm), o carbono orgânico particulado (COP), o nitrogênio total particulado (NTP) nas classes de agregado, o C orgânico total (COT) e o nitrogênio total (NT) na amostra integral e nas classes de agregados e a resistência tênsil dos agregados. A relação de estratificação (RE) foi calculada dividindo-se o valor de COT e NT da camada de 0-5 cm pelo valor na camada 5-20 cm. A taxa de seqüestro de C e a variação da relação de estratificação foram calculadas através da diferença (D) entre os valores da E2 menos o da E1. A resistência tênsil (RT) do solo foi avaliada em 1920 agregados de cada época de coleta, determinando-se, também o conteúdo de COT e NT. A classe de agregado > 8 mm representou mais de 70% da massa dos agregados tanto na textura argilosa como na arenosa. Da mesma forma, o conteúdo de COT e NT foram maiores na classe de agregado > do que 4 mm comparado as demais classes nas duas classes texturais. A relação de estratificação 5:5-20 cm) de COT, NT, COP e NTP do solo indicou a melhoria da qualidade do solo da camada superficial. A relação linear e significativa entre o DRE com a taxa de seqüestro de carbono nas duas classes texturais mostrou o aumento no seqüestro de C e foi mais evidente no LV com textura média. O incremento do conteúdo de COT resultou na diminuição da resistência tênsil (RT) dos agregados e foi mais evidente na camada de 0-5 cm. A RT apresentou relação inversa com a densidade do solo e foi superior no LV textura média. A taxa de seqüestro de C foi de 0,86 para o LV textura média e 0,76 Mg ha-1 para o textura argilosa e para manter o equilíbrio estável de C é necessário o aporte de 8,6 Mg ha-1 de resíduos culturais. Os resultados apresentados confirmaram a hipótese da RE ser um indicador sensível para a taxa de seqüestro de carbono no solo em um sistema sob plantio direto consolidado.

As the world population has exceeded 7 billion in 2011, the global awareness of sustainability arises more than ever since we are facing unprecedented challenges in energy, water, material and climate change, in order to sustain our current and future generations on this planet. The Guardian has named the Iron Bridge opened in 1781 across the River Severn, Shropshire, UK as the cradle of the modern world, which is the world's first cast-iron bridge and remains as the enduring symbol of the Industrial Revolution (Guardian, 2009). Ever since, in the spanning of 250 years, iron and steel have been the cornerstone of modern industries from developed countries to developing ones especially for those which are still experiencing their major urbanization process. Nevertheless, iron and steel making are among the most raw material-dependent and energy intensive industries with large gaseous pollutants, CO2 and waste generations in the world. Therefore there is a pressing need to solve these resource and environmental problems associated with the iron and steel making. This work addresses a number of challenges stated above by focusing on the improvement of the overall sustainability of this highly energy-intensive industry via (1) utilizing inexpensive iron ore tailings to enhance the material sustainability, (2) CO2 reduction by mineral carbonation using its own solid waste stream, i.e., iron and steel slags, and (3) slag valorization through the use of carbonated slags as sustainable construction materials. This work begins with the study of an ironmaking plant using the direct reduced iron (DRI) process, which is a molten iron production method utilizing fluidized bed and melter-gasifier technologies. This technology allows the direct production of the molten iron using the inexpensive iron ore tailings and the non-coking coal, during a gas-solid reaction in the fluidized bed. Practically, a higher percentage of the fine particles (i.e., iron ore tailings) is favored to mix in the feedstock because it is cheaper than the traditionally used coarse particles (i.e., bulk and fine iron ores). The challenge of this novel technology is attributed to the entrainment of the fine particles during the gas-solid fluidization. Since the electrostatic phenomenon was significant during the particulate fluidization systems which might affect the particle entrainment, the electrostatic charge generation and accumulation were investigated for binary and quaternary particulate systems. Specifically, the effect of the addition of two different iron ore tailings (i.e., hematite and magnetite) in the fluidized bed was studied in terms of particle-particle interactions, electrostatics, and entrainment rates. The behaviors of different particulate systems were found to be highly dependent on the chemical and physical properties of the particles. The results suggested that the enhanced electrostatic forces between the fine and coarse particles due to the electrostatic charging during the fluidized bed operation retained the fines to some extent and the sintering of the fine particles could happen on the surface of the coarse particles during the iron ore reduction. Therefore, for this fluidized bed based DRI process, iron ore tailings are proved to be able to replace the coarse iron ores to the extent that fine particles will sinter but not be entrained and thus the overall cost of raw materials could decrease. In iron and steel making, limestone and dolomite are also mixed in the feedstock to remove the impurities of the iron ores, mostly silica, which forms slag as a silicate-based material in the downstream of this process. Slags of different types have been reused as cement clinker, aggregate, road base and fertilizer. Recently, iron and steel slags have also been deemed as alternatives for mineral sequestration because these slags are similar to natural Ca/Mg-bearing silicate minerals. The accelerated weathering of natural minerals or industrial wastes is an environmentally benign route to thermodynamically stabilize carbon. Thus, another study of this work is fixing the CO2, especially emitted from the iron and steel plant, into the slag, a solid waste generated from the same processing stream. In particular, the stainless steel slag has been a focus since its application in construction materials has been limited due to the high content of FeO and the environmental concern of heavy metals leaching (e.g., Cr). Along with the iron and steel making, the cement industry is also among the largest industrial CO2 emitters. Mixing carbonated slags as a filler material in the cement mortar while guaranteeing the overall quality of the cementitious material could reduce the usage of limestone and the carbon emissions from limestone calcination and reduce energy input during the cement production. In this study, the production of environmentally benign cementitious material was coupled with the direct carbonation of stainless steel slag. Compressive strength, exothermic behavior and leaching behavior of the mixed cement mortar were investigated. Particularly, mixing 10 wt% of the direct carbonated stainless steel slag sample prepared at 30 °C in a Portland cement did enhance the compressive strength of the cement mortar. Also, the mixing retarded the hydration and overall setting time. Finally, the Cr leaching of the cement mortar with the addition of the direct carbonated stainless steel slag was minimized. Thus, the iron and steel industry and cement industry should collaborate, to minimize their overall material input, energy usage and carbon emission jointly. During the direct carbonation, stainless steel slag and CO2 flows are introduced into the solvent simultaneously. Whereas for the two-step process, calcium ions are extracted from the solid matrix into an aqueous phase, and then the CO2 is bubbled through and reacts with the Ca. The two-step route allows optimizing the conditions for both the dissolution and the carbonation. Moreover, the precipitated end products (e.g., precipitated calcium carbonates, PCC) from the two-step process, normally with higher quality compared to direct carbonated slags, can be adapted for various industrial and construction applications. However, the overall reaction is constrained by the kinetics of the stainless steel slag dissolution. Thus several organic and inorganic chelating agents were applied in order to accelerate the dissolution. Some of these agents were found to be desirable for the dissolution of stainless steel slag at different pH via the differential bed study. Ligand concentration and temperature affected the extent of the extraction in the batch reactor. For the carbonation step, PCC from the modeled chemical solution and the dissolved stainless steel slag solution were non-identical, which was also affected by the reaction pH and temperature. The properties of the PCC prepared in the batch reactor and the bubble column reactor were also found to be dissimilar. Thus, for an iron and steel plant that adopts the two-step carbonation of slags for CO2 reduction, the end products could be engineered by tuning the reaction conditions to meet different end-user requirements. On the other hand, there have been significant efforts to reduce the cost of the two-step carbonation, including the utilization of value-added byproducts like iron oxide. In particular, silicate minerals or industrial waste often contain 5~20 wt% of Fe and by dissolving the iron into aqueous phase, a variety of Fe-based materials can be synthesized by precipitation. In this work, Fe-based catalysts were synthesized from serpentine and stainless steel slag (SSS) and applied to the biomass-to-hydrogen conversion via an alkaline thermal treatment pathway. The synthesized Fe-based materials were compared with the purchased hematite and magnetite and the reduced Fe-based catalyst derived from SSS was found to be catalytically active. This suggests an opportunity to produce inexpensive catalysts from the solid waste of the iron and steel making. Finally, a novel iron making scheme based on a fluidized bed DRI system was proposed by this study. It combined all the studies above that inexpensive iron ore tailings were used as a feedstock for the iron production, slags were utilized for sequestering CO2 and ended as filler materials for cement mortar. Preliminary economical and life cycle assessment was investigated based on the current scale of an existing industrial plant. An economically, environmentally and ecologically favored iron, steel and cement production system could be potentially achieved with improved overall material sustainability and carbon footprint.

To curb greenhouse gases and mitigate climate change is one of the biggest challenges human society face today. Carbon dioxide (CO2) has accumulated rapidly in the atmosphere as a consequence of burning of fossil fuels and deforestation. The aim of this study is to explore two methods to store carbon dioxide in geological formations and biological sinks. The aim is also to discuss the two mitigation options from a sustainable perspective and whether it can lead to a better environment and benefits for local and global societies. The research questions are: Which method to store carbon dioxide, geological or biological, is the most effective? Which method to store carbon dioxide, geological or biological, has the greatest potential to promote sustainable development for local communities? The method used is a comparative case study and presents four case studies that explore the potential for CO2 storage offshore in Norway and Brazil; and in tropical forests in Mexico and Brazil. The mitigation options are discussed from two different theoretical perspectives. The principle of the theory of ecological modernisation is that innovation and environmentally friendly technology can solve the environmental problems human societies face today, whereas the theory of common pool resources promotes local communities to govern limited resources in order to manage them sustainably. The findings suggest that ecological modernisation legitimize environmental destruction as carbon dioxide storage in geological formations (CCS) use the technology as a mean to extract more oil and gas; which results in a rebound-effect. Therefore, carbon dioxide capture in geological formations is not a realistic method unless it can prevent further emissions. Protected forest resources can be seen as biological insurance, which safeguard ecosystem services, biodiversity, and the forest potential to hold carbon. Carbon sequestration in tropical forest has the potential to store carbon dioxide given that the forests are protected and local communities have tenure rights, knowledge, and the means to protect the forest and manage them sustainably.

No description available.

Of all the strategies to reduce carbon emissions, carbon dioxide (CO₂) geological sequestration is an immediately available option for removing large amounts of the gas from the atmosphere. However, our understanding of the transition behavior between Forchheimer and Darcy flow through porous media during CO₂ injection is currently very limited. In addition, the kinetic mass transfer of SO₂ and CO₂ from CO₂ stream to the saline and the fully coupling between the changes of porosity and permeability and multiphase flow are two significant dimensions to investigate the brine acidification and the induced porosity and permeability changes due to SO₂ co-injection with CO₂. Therefore, this dissertation develops a multiphase flow, contaminant transport and geochemical model which includes the kinetic mass transfer of SO₂ into deep saline aquifers and obtains the critical Forchheimer number for both water and CO₂ by using the experimental data in the literature. The critical Forchheimer numbers and the multiphase flow model are first applied to analyze the application problem involving the injection of CO₂ into deep saline aquifers. The results show that the Forchheimer effect would result in higher displacement efficiency with a magnitude of more than 50% in the Forchheimer regime than that for Darcy flow, which could increase the storage capacity for the same injection rate and volume of a site. Another merit for the incorporation of Forchheimer effect is that more CO₂ would be accumulated in the lower half of the domain and lower pressure would be imposed on the lower boundary of the cap-rock. However, as a price for the advantages mentioned above, the injection pressure required in Forchheimer flow would be higher than that for Darcy flow. The fluid flow and contaminant transport and geochemical model is then applied to analyze the brine acidification and induced porosity and permeability changes due to SO₂ co-injection. The results show that the co-injection of SO₂ with CO₂ would lead to a substantially acid zone near the injecting well and it is important to include the kinetic dissolution of SO₂ from the CO₂ stream to the water phase into the simulation models, otherwise considerable errors would be introduced for the equilibrium assumption. This study provides a useful tool for future analysis and comprehension of multiphase Darcy-Forchheimer flow and brine acidification of CO₂ injection into deep saline aquifers. Results from this dissertation have practical use for scientists and engineers concerned with the description of flow behavior, and transport and fate of SO₂ during SO₂ co-injection with CO₂ in deep saline aquifers.

Dans la dernière décennie, plusieurs hectares de terre agricole ont été convertis à la culture intensive sur courtes rotations (CICR) de saules dans le sud du Québec (Canada). Peu d’études ont été réalisées afin de déterminer comment se comporte la dynamique du carbone organique (Corg) dans le sol suivant cette conversion. Nous avons donc comparé la quantité du Corg et de deux pools labiles de carbone (carbone extractible à l’eau chaude et les sucres aminés) entre des CICR en phase initiale d’établissement (1-2 ans) et des parcelles appariées représentant le système de culture qui prévalait avant la transformation en culture de saules (culture fourragère) et d’autres cultures d’intérêt. La même chose a été faite pour une CICR en exploitation (depuis 9 ans) à un autre site. La quantité de Corg du sol n’était pas différente entre les CICR et les parcelles sous culture fourragère. Une plus haute concentration de sucres aminés dans le Corg total des CICR en établissement, par rapport aux autres parcelles sur le même site, permet de soupçonner que les perturbations liées à l’établissement ne mènent pas à une minéralisation accrue du Corg à court terme. La proportion de sucres aminés fongiques, qui diminue théoriquement lors de perturbations, était aussi plus élevée sous la plus jeune culture. Sous la CICR de neuf ans, le Corg était redistribué dans le profil vertical et les pools labiles étaient de plus petite taille (à une profondeur de 20-40 cm) comparativement à une parcelle témoin. La conversion d’une culture fourragère en plantation de saules en CICR n’a pas mené à la formation d’un puits de carbone. L’étude laisse entrevoir qu’un tel puits pourrait être créé si la conversion se faisait à partir d’un aménagement impliquant la culture en rotation de plantes annuelles et des labours. / Over the last ten years, many hectares of short-rotation willow coppice (SRWC) have been established on abandoned agricultural lands in southern Quebec (Canada). However, few studies were conducted to determine if these changes from a conventional crop to SRWC of willows would affect the soil carbon dynamic. A preliminary paired-site study was conducted to assess the impact of this land-use conversion on soil carbon stocks and dynamics shortly after they were established (1-year and 2-year) at one site and after multiple rotations (9-year) at another site. Apart from the total soil organic carbon pool, two labile carbon pools were investigated: the hot-water extractable carbon (HWC) pool and the amino sugars (AS) pool. Willow establishment and exploitation for nine years did not bring any changes in total organic carbon compared to an abandoned hay culture. The mature SRWC displayed a redistribution of TSOC in the vertical soil profile. We also measured a higher proportion of AS, compared to other plots on the same site, in total organic carbon under the 1-year-old SRWC; especially the proportion in AS of fungi origin that theorically decrease with perturbation intensity. Proportion of AS was also elevated under 2-year-old SRWC. A possible interpretation is that establishment-linked perturbations did not shift carbon dynamic toward an increased mineralization. The mature willow plantation exhibited depletion of HWC and the more labile amino sugar (muramic acid) in the deeper soil layer (20-40cm). This case study shows that conversion from an abandoned hay culture to a SRWC did not create a carbon sink. It was also found that the 9- year old willow plantation contained higher TSOC and had better soil quality than an adjacent short-term no-till crop rotation culture.

Orientador: Osmar de Carvalho Bueno / Banca: Maria Aparecida Mourão Brasil / Banca: Thelma Krug / Resumo: O alerta de cientistas sobre o aquecimento do planeta vem desde a década de 60. Entretanto, a comunidade internacional passou a discutir mais profundamente o tema a partir dos anos 80, mas foi na década de 90 que se conseguiram os maiores avanços diplomáticos, com o advento da Convenção-Quadro das Nações Unidas sobre Mudança do Clima e suas Conferências das Partes, onde em 1997 negociou-se o Protocolo de Quioto. Este trabalho discorre sobre a regulamentação internacional relacionada ao aquecimento global, enfocando em particular o papel da agroenergia brasileira dentro do Mecanismo de Desenvolvimento Limpo (MDL) e seu potencial de mitigação para a mudança climática. . Utiliza-se do método dedutivo para o desenvolvimento da dissertação. A atuação do Brasil apresenta-se controversa, pois é grande emissor de gases de efeito estufa (GEE) decorrente do desmatamento. Entretanto, a agroenergia brasileira destaca-se no cenário mundial com o grande potencial de substituição de matrizes energéticas não-renováveis por renováveis. Conclui-se que a agroenergia brasileira poderá contribuir para a mitigação do efeito estufa A discussão enfocou a demonstração da adicionalidade nos projetos de MDL, o potencial dos projetos de co-geração de energia e a necessidade de incluir no segundo período de compromisso do Protocolo de Quioto atividades relacionadas a uso da terra e mudança do uso da terra como ferramentas que contribuem para o controle do aquecimento global. As conclusões indicam a diferenciação entre projetos de redução de emissão e projetos de MDL; a potencialidade da agroenergia e o trabalho do Brasil para se destacar no mercado de carbono. / Abstract: Scientists have been warning about the planet warming since the 1960s. However, the international community started discussing it more deeply in the 1980s, but it was in the 1990s that the greatest diplomatic advances were reached, with the United Nations Framework Convention on Climate Change and its Conference of Parties when, in 1997, the Kyoto Protocol was negotiated. This study concerns the international regulation related to global warming, focusing on the particular Brazilian agroenergy role within the Clean Development Mechanism (CDM) and its mitigation potential to the climate change. The deductive approach was used in this paper. The Brazilian performance is antagonistic, once it is a great greenhouse gas emissary due to deforestation. Nevertheless, the Brazilian Agroenergy stands out in the world scenario with the huge replacement potential from nonrenewable energetic matrix to renewable ones. In this way, it is possible to conclude that the Brazilian Agroenergy can contribute to the greenhouse effect reduction. The discussion focused on the addition demonstration on CDM projects, the energy cogeneration potential of the projects, and the need to include activities concerning the land use and land use changes as a tool that comes through the global warming control in the second commitment period of Kyoto Protocol. The conclusion shows the difference between the reduction emission projects and the CDM projects; the agroenergy potencial as well as the Brazilian effort to stand out in the carbon market. / Mestre

A atividade humana tem contribuído com as emissões de gases de efeito estufa (GEE) associadas, principalmente, com queima de combustíveis fósseis e mudanças no uso da terra. Assim, se faz necessário que sejam adotadas medidas visando o retardamento dos efeitos das mudanças climáticas. As florestas exercem papel essencial no balanço de carbono principalmente por funcionarem como sumidouros de CO2. Por outro lado, se desmatadas, promovem emissões e liberam parte do carbono estocado. A quantidade de biomassa florestal e o teor de carbono podem variar em função do tipo florestal, bem como de sua localização. Entretanto, fator importante diz respeito à confiabilidade dos dados mensurados neste tipo de pesquisa. A biomassa e o carbono da parte aérea podem ser determinados via método destrutivo, ou estimados via método não destrutivo. A construção do Rodoanel Mário Covas trecho norte e a supressão de uma área de Mata Atlântica possibilitou a realização de estudo de biomassa da parte aérea via método destrutivo. O objetivo deste trabalho foi estudar o tamanho e forma de parcelas, a intensidade amostral, quantificar a biomassa e o carbono na parte aérea, comparar métodos destrutivos e não destrutivos para a quantificação de biomassa e carbono na parte aérea, estudar a variação da densidade básica da madeira das espécies nas diferentes classes de DAP e grupos sucessionais e comparar as medidas de altura total e DAP obtidas a campo no inventário com as medidas coletadas após o corte. O tamanho mais conveniente de parcela foi 400 m 2, com forma retangular e dimensão de 10 x 40 m. A intensidade amostral variou entre 39 e 75 unidades amostrais. A biomassa da parte aérea obtida, via método destrutivo, foi de 188,3 Mg ha-1 e o carbono, 85,1 Mg ha-1. A biomassa estimada por equações alométricas da literatura foi subestimada, quando comparada ao valor real, obtido via método destrutivo. As menores classes de DAP apresentaram as maiores densidades básicas da madeira. A densidade básica foi 0,488 g cm-3 na média das espécies. A porcentagem de carbono contida nos troncos e galhos não diferiu entre as classes de DAP. O teor de carbono foi 45,41%, na média dos troncos e galhos. Espécies pioneiras acumularam maior quantidade de biomassa e carbono nos galhos e apresentaram maior densidade básica que as não pioneiras. A utilização dos dados coletados na fase de inventário e após o corte não afetaram os valores de biomassa estimados. / Human activity has contributed to the emission of greenhouse gases associated mainly with burning fossil fuels and changes in land use. Thus, it is necessary that measures be adopted to delay the effects of climate change. Forests play an essential role in the carbon balance mainly acting as CO2 sinks. On the other hand, if they are deforested, they will promote emissions and release some of the stocked carbon. The amount of forest biomass and the carbon content may vary depending on the forest type and its location. However, an important factor is about the reliability of the data measured in this type of research. Aboveground biomass and carbon can be determined via destructive method or estimated by non-destructive method. The construction of the north extension of Mário Covas Road and the suppression of an Atlantic forest area made it possible to carry out study of the aboveground biomass via destructive method. The goal of this work was to study the size and shape of plots, the sampling intensity, their aboveground biomass and carbon, compare destructive and non-destructive methods for the quantification of biomass and carbon, study the variation of wood basic density in the species in different classes of diameter of trunk at breast height (DBH) and successional groups and compare the total height and DBH measures obtained on field in the inventory with the measures taken after the cut. The most convenient plot size is 400 m2, with rectangular shape and size of 10 x 40 m. The sampling intensity varied between 39 and 75 sample units. The aboveground biomass obtained, via destructive method, was 188.3 Mg ha-1 and carbon, 85.1 Mg ha-1. The biomass estimated by allometric equations of the literature was underestimated compared to the real value obtained via destructive method. Smaller DBH classes had the highest wood basic density. The basic density was 0.488 g cm-3 in average of the species. The percentage of carbon contained in the trunks and branches did not differ between the DBH classes. The carbon content was 45.41%, in the average of the trunks and branches. Pioneer species accumulated higher amount of biomass and carbon in the branches and had a higher wood basic density than non pioneers species. The utilization of data collected in the inventory phase and after the cut did not affect the estimated biomass values.