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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
391

COMPARTIMENTOS DA MATÉRIA ORGÂNICA DO SOLO COMO INDICADORES DO SEQÜESTRO DE CARBONO EM SISTEMA PLANTIO DIRETO DE LONGA DURAÇÃO

Ferreira, Ademir de Oliveira 13 July 2009 (has links)
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.
392

Sustainable Iron and Steel Making Systems Integrated with Carbon Sequestration

Zhou, Xiaozhou January 2015 (has links)
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.
393

Koldioxidlagring - realitet eller utopi? : En komparativ fallstudie med syfte att undersöka potentialen för koldioxidlagring i geologiska formationer och biologiska sänkor och dess förmåga att bidra till hållbar utveckling

Holgerson, Line January 2013 (has links)
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.
394

Carbon Finance Schemes in Indonesia / Empirical Evidence of their Impact and Institutional Requirements / Kohlenstoff-Finanzierungsprogramme in Indonesien / Empirische Untersuchung ihrer Auswirkungen und institutioneller Rahmenbedingungen

Seeberg-Elverfeldt, Christina 30 October 2008 (has links)
No description available.
395

Numerical investigation of multiphase Darcy-Forchheimer flow and contaminant transport during SO₂ co-injection with CO₂ in deep saline aquifers

Zhang, Andi 20 September 2013 (has links)
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.
396

Évaluation du potentiel de séquestration de carbone dans le sol de cultures intensives sur courtes rotations de saules dans le sud du Québec

Lockwell, Jérémie 08 1900 (has links)
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.
397

O potencial da agroenergia no Brasil na mitigação do clima : histórico jurídico /

Rudge, Vânia Vieira Cunha, 1980- January 2005 (has links)
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
398

Quantificação de biomassa e carbono da parte aérea em uma área de Mata Atlântica, na Serra da Cantareira, São Paulo / Quantification of aboveground biomass and carbon in an Atlantic Forest area, at Serra da Cantareira, São Paulo

Tiago Cavalheiro Barbosa 15 February 2016 (has links)
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.
399

Dendrocronologia de árvores de Tectona grandis L. e Pinus caribaea var. hondurensis Barr. et Golf de plantação da Mata da Pedreira, Campus da ESALQ-USP, Piracicaba, SP / Dendrochronology of Tectona grandis L. and Pinus caribaea var. hondurensis Barr. et Golf. trees from plantation of Mata da Pedreira, Campus ESALQ-USP,Piracicaba,SP.

Alejandro Danilo Venegas González 31 October 2013 (has links)
As árvores de Tectona grandis (Verbenaceae) e de Pinus caribaea var. hondurensis (Pinaceae) são utilizadas em estudos dendroecológicos e dendroclimatológicos pela formação de anéis de crescimento anuais duas espécies plantadas na Mata da Pedreira do Campus da ESALQ/USP para estudos ecológicos e climáticos. Foram selecionadas 8 árvores de Tectona grandis (4 com e 4 sem lianas ocupando a copa das árvores) e 10 árvores de Pinus caribaea var. hondurensis (8 vivas - 4 com e 4 sem lianas ocupando a copa das árvores - e 2 mortas). Com a utilização de sondas de Pressler foram extraídas 2-6 amostras do lenho/árvore das 2 espécies para analisar seus anéis de crecimiento. Foi realizada (i) a caracterização anatômica macro e microscópica dos anéis de crescimento; (ii) estudos de dendrocronologia, pela datação e avaliação do crescimento radial do tronco das árvores; (iii) avaliação da densidade do lenho por densitometria de raios X para a determinação da densidade dos anéis de crescimento, incremento de biomassa e de carbono; (iv) avaliação da influência do clima local e em grande escala no crescimento do tronco das árvores; (v) análise dos vasos das árvores de T. grandis e dos anéis de crescimento falsos nas árvores de P. caribaea. Os resultados principais mostraram que as características anatômicas dos anéis de crescimento das árvores as 2 espécies coincidem com os descritos na literatura; a série de anéis de crescimento mostrou correlação significativa em relação à sincronização dos anéis de crescimento das árvores das 2 espécies. O efeito prejudicial das lianas na copa das árvores de T. grandis e de P. caribaea foi comprovado pela redução da largura dos anéis de crescimento no período de 2000-11 e de 1971-2011, respectivamente. A densidade aparente média dos anéis de crescimento (T. grandis: 0,64 g/cm3 e de P. caribaea: 0,60 g/cm3) permitiu calcular o incremento de massa de carbono, resultando que as árvores sem lianas apresentam maior estoque de carbono do que as com lianas. A análise dendroclimatológica mostrou que as árvores de P. caribaea apresentaram correlações positivas com a disponibilidade de água no solo no período de seca; as árvores de T. grandis mostram correlação positiva com o período de maior chuva, temperatura de primavera e a oscilação antártica (AAO) de outono no ano corrente de crescimento, e correlação negativa com o evento de El Niño (TNI) em outono anterior. A ocupação das lianas na copa das árvores de T. grandis provocou o aumento da área dos vasos; os vasos do lenho inicial (e sua frequência) mostraram correlação significativa com a largura dos anéis de crescimento, possibilitando a construção de cronologias desses parâmetros e a avaliação da influência climática nas árvores. A ocupação das lianas na copa das árvores de P. caribaea induziu diminuição da frequência dos anéis de crescimento falsos, formados, principalmente, pelo aumento das pricipatações de Julio anterior y verão (DJF) e corrente. Os resultados deste estudo permitiram concluir que a análise dos anéis de crescimento das árvores das 2 espécies tem grande potencial para estudos ecológicos e ambientais no Brasil. / The trees of Tectona grandis (Verbenaceae) and Pinus caribaea var. hondurensis (Pinaceae) are used in dendroecological and dendroclimatologal studies by formation the annual growth rings. For these reasons, the study aimed to examine the tree-rings of the two species planted in Mata da Pedreira in Campus ESALQ/USP to climatic and ecological studies. We selected eight T. grandis trees (4 with and 4 without lianas occupying the trees canopy) and 10 P. caribaea trees (8 live - 4 with and 4 without lianas- and 2 dead). With the use Pressler increment borer was extracted 2-6 wood samples/tree of two species to analyze their trees-rings growth. Were applied: i) anatomical characterization macro and microscopic of trees-rings; ii) dendrochronology studies, by dating and evaluation of the trees radial growth; iii) evaluating the density of the wood by X-ray densitometry for determination of tree-rings density, biomass and carbon increment; iv) evaluating of influence of local climate and large-scale on tree-rings; v) Analysis of the vessel in T. grandis trees and false rings in P.caribaea trees. The main results showed that the anatomical characteristics of trees-rings of the both species coincide with those described in the literature; the series of trees-rings showed significant correlation with respect to the synchronization of trees-rings in the two species. The unfavorable effect of lianas in the canopy of trees T. grandis and P. caribaea was confirmed by the reduction of the tree-rings width in period 2000-2011 and 1976-2011, respectively. . The apparent density average of tree-rings (T. grandis: 0,64 g/cm3 e de P. caribaea: 0,60 g/cm3) allowed us to calculate the increase of carbon mass, resulting that trees without lianas had higher carbon stocks than those with lianas. The climatological analysis showed that P. caribaea showed positive correlations with water availability in the soil in the dry season; T. grandis trees showed positive correlations with period of highest rainfall, temperature of spring and AAO of fall in the current growing season, and negative correlation with El Niño event (TNI) in the fall. The ocupation of lianas on T. grandis trees caused the increase of the vessels area; the earlywood vessels (and frequency) had a significant correlation with the tree-rings, allowing build of chronologies of these parameters and evaluate the influences climate in the trees. The ocupation of lianas on P. caribaea trees induced a decrease in false rings, which are formed primarily by the increase of the previous July and current summer (DJF). The results of this study showed that the tree-rings analysis of the two species has great potential to ecological and climatical studies in Brazil.
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Matéria orgânica de um argissolo vermelho distrófico úmbrico após a introdução de fitofisionomias antrópicas / Organic matter in argissolo vermelho distrófico úmbrico after introduction of anthropogenic fitofisionomys FITOFISIONOMYS.

Soares, Julio Cesar Wincher 04 May 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the state of Rio Grande do Sul the expansion of forestry has been one of the major agents of landscape change, occupying land previously intended for livestock farming and agriculture with low technical level, in areas under the influence of the Pampa biome and the transition of this biome for the Atlantic Forest. There is a widespread belief about the negative impacts caused by forest plantations on natural resources. Thus, it is necessary to evaluate the impacts caused by the introduction of forest plantations on the landscape components, especially on the soil and organic matter. This study was performed to characterize the components of the landscape topography, vegetation cover and their relations with soil, as well as temporal variation in soillandscape Forestry Experiment Station, located in the central region of Rio Grande do Sul were also found, changes in inventory levels and nitrogen (N and SN) and organic carbon (CO and SCO) in profiles Typic Umbrian and the labile and stable organic matter in surface horizon of the soil under native forest at the intermediate stage regeneration and field man-made with over 35 years, mixed forest of Eucalyptus and Eucalyptus robusta 35, forest of Eucalyptus grandis with 4 and 21 years, forest of Acacia mearnsii at age 7, forest of Eucalyptus saligna and 6 years mixed forest with Pinus 10 years. The results indicated that there is a transitory components of the landscape between the edge of the Southern Rio Grande Plateau and the Central Depression of Rio Grande do Sul, as well, there is a characterization of the natural vegetation types and conflicts of land use. It was also found that the relief and the genesis of the soils were vegetational conditions for development and that in 22 years there have been expanding cultivation of Eucalyptus and Pinus and the native forest on the anthropic field, especially in lands with Argissolos Bruno-Acinzentados and Argissolos Vermelhos. The organic matter of Argissolo Vermelho distrófico úmbrico, the results suggest that the levels and stocks of nitrogen and organic carbon of their surface horizon, altered by the introduction of man-made forest and field areas of deciduous forest, with a decrease especially in land occupied by forest of Acacia mearnsii and field of human activity. In relation to the stocks of organic carbon and nitrogen in the soil profile had a greater influence of other factors and processes of soil formation than the occupation of land in the last four decades. We also observed changes in the distribution of particulate organic carbon (POC g.kg-1) in the surface horizon of the soil, and this organic matter fraction of a sensitive indicator of changes in land use and soil. / No estado do Rio Grande do Sul a expansão da silvicultura tem atuado como um dos principais agentes de alteração da paisagem, ocupando terras anteriormente destinadas à pecuária extensiva e à agricultura com baixa tecnificação, em áreas sob a influência do bioma Pampa e na transição desse bioma para o de Mata Atlântica. Existe uma crença generalizada acerca dos impactos negativos ocasionados pelas plantações florestais sobre os recursos naturais. Assim, faz-se necessária a avaliação dos impactos causados pela introdução dos plantios florestais sobre os componentes da paisagem, principalmente sobre o solo e sua matéria orgânica. Neste estudo foi realizada a caracterização dos componentes da paisagem relevo, cobertura vegetal e suas relações com os solos, além da variação temporal da relação solo-paisagem numa Estação Experimental de Silvicultura, localizada na região central do Rio Grande do Sul. Foram verificadas também, as alterações nos teores e estoques de nitrogênio (N e SN) e de carbono orgânico (CO e SCO) em perfis de Argissolo Vermelho distrófico úmbrico e as frações lábeis e estáveis da matéria orgânica do horizonte superficial desse solo sob a Floresta nativa em estágio médio de regeneração e campo antrópico com mais de 35 anos, floresta mista do gênero Eucalyptus e de Eucalyptus robusta com 35 anos, floresta de Eucalyptus grandis com 4 e 21 anos , floresta de Acacia Mearnsii com 7 anos, floresta de Eucalyptus saligna com 6 anos e floresta mista do gênero Pinus com 10 anos. Os resultados indicaram que há um caráter transitório nos componentes da paisagem, entre o Rebordo do Planalto Sul-Riograndense e a Depressão Central do Rio Grande do Sul, como também, existe uma descaracterização das fitofisionomias naturais e a existência de conflitos de uso do solo. Constatou-se também, que o relevo e a gênese dos solos foram condicionantes para o desenvolvimento fitofisionômico e que em 22 anos houve expansão dos cultivos de Eucalyptus e Pinus, e da floresta nativa sobre o campo antrópico, principalmente nas terras com Argissolos Bruno-Acinzentados e Argissolos Vermelhos. Quanto à matéria orgânica do Argissolo Vermelho distrófico úmbrico, os resultados sugerem que os teores e estoques de nitrogênio e carbono orgânico do seu horizonte superficial, apresentam alterações frente à introdução de florestamentos e do campo antrópico sobre áreas de Floresta Estacional Decidual, havendo decréscimo principalmente em terras ocupadas pela floresta de Acacia Mearnsii e campo antrópico. Já em relação aos estoques de nitrogênio e carbono orgânico no perfil do solo, houve maior influência dos demais fatores e processos de formação do solo do que a ocupação das terras nas últimas quatro décadas. Foram constatadas também alterações na distribuição do carbono orgânico particulado (POC g.kg-1) no horizonte superficial do solo, sendo esta fração da matéria orgânica um indicador sensível às alterações no uso e ocupação do solo.

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