Thesis (Ph. D.)--Institute of Paper Chemistry, 1963. / Bibliography: leaves 114-117.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2016-07-26T18:36:18Z No. of bitstreams: 1 Rodrigues, AMS..pdf: 1544198 bytes, checksum: f7812f307a7c02140fee10e18cdabb47 (MD5) / Made available in DSpace on 2016-07-26T18:36:18Z (GMT). No. of bitstreams: 1 Rodrigues, AMS..pdf: 1544198 bytes, checksum: f7812f307a7c02140fee10e18cdabb47 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências (Geoquímica). Niterói, RJ / A Baía de Guanabara está localizada na região metropolitana da cidade do Rio de Janeiro e ao longo dos últimos séculos vem sofrendo diversas modificações devido ao intenso crescimento urbano e industrial. Este trabalho teve como objetivo caracterizar a matéria orgânica de dois perfis sedimentares localizados nas regiões interna (BG1) e de entrada (BG2) da Baía de Guanabara através da composição de C, N e fenóis da lignina como indicadores da deposição do material terrígeno ao longo dos últimos 3500 anos. Durante o último século os teores de COT e NT no BG1 indicaram um aumento crescente em direção ao topo do testemunho com valor máximo de 3,4 % de carbono na camada superficial e razão C/N próximo a 10 indicando mistura de fontes terrígenas e marinhas com maior contribuição resultante da eutrofização nas camadas superiores. Para as fases que correspondem de 3520 AP a 750 AP os teores de carbono e nitrogênio foram menores, ressaltando um aumento pontual na fase V, em torno de 2050 AP, com valores de 3,5% e 0,2, respectivamente e razão C/N de 17,3 e foi relacionado a variação do nível do mar. O BG2 apresentou valores maiores quando comparado com o BG1. Da base, em torno de 810 anos AP, ao topo as maiores oscilações foram nas camadas recentes com valores entre 2,0 % e 5,3 % de carbono, e entre 0,19% e 0,51% de nitrogênio e razão C/N entre 9,4 e 11,7. Os teores de lignina oscilaram entre 0,63 a 46,76 mg.100 mg de CO-1 no BG1 0,04 a 2,9 no BG2 mg.100 mg de CO-1, confirmando a presença de material alóctone de plantas vasculares. A razão entre os grupos fenólicos (S/V e C/V) apresentaram maiores valores das razões S/V sobre C/V. A predominância de material proveniente dos solos nas fases superiores e enriquecidos por restos de plantas vasculares nas camadas da base foram evidenciados pelos índices diagenéticos (Ad/Al)V e 3,5Bd/V, e indicaram a intensificação de processos erosivos e maiores perdas de solos por escoamento superficial nas camadas recentes. Atipicamente no período de aproximadamente 2050 AP foi identificado elevada quantidade de material preservado característico de restos de plantas vasculares. Durante o último século maiores taxas de acumulação de carbono, nitrogênio e lignina foram registrados e foram relacionadas as modificações no uso do solo devido a intensificação do processo de urbanização ocorridos nas regiões de influência de ambos os testemunhos BG1 e BG2. Inicialmente o aumento nos fluxos de carbono foi acompanhado de lignina. No entanto, a partir da década de 90, esse comportamento não teve continuidade na região interna da Baia, com aumento no fluxo de carbono sem a mesma participação da lignina. Na entrada da baia o mesmo foi observado a partir de 2000, destacando maiores valores para as taxas de acumulação de lignina, e principalmente em 2005 quando ocorreu um aumento brusco de lignina sem incremento do carbono. A presença de fenóis de lignina encontrado em concentrações diferentes significa que a contribuição de matéria orgânica de origem alóctone existe, no entanto a mesma pode está sofrendo diferentes taxas de diluição e degradação ao longo do transporte e deposição e por esse motivo pode ser encontrado em concentrações diferenciadas. Para as camadas recentes do topo dos perfis sedimentares, BG1 e BG2, o fluxo de lignina diminui e o fluxo de C aumentou, indicando que a contribuição de matéria orgânica de origem vascular para os dois ambientes foram menores / The Guanabara Bay is located in the metropolitan area of the city of Rio de Janeiro and over the past centuries has undergone several changes due to intense urban and industrial growth. This study aimed to characterize the organic matter of two sedimentary profiles located in the inner regions (BG1) and input (BG2) of Guanabara Bay by C, N and lignin phenols compositions as indicators of deposition of terrigenous material along the last 3500 years. During the last century the TOC and NT in BG1 indicated an increasing toward the top of the sedimentary profile with maximum value of 3.4% carbon in the surface layer and C / N ratio close to 10 indicating mixture of terrigenous 6and marine sources with more eutrophication resultant of contribution in the upper layers. For the phases that correspond 3520 BP at 750 BP the carbon and nitrogen levels were lower, emphasizing one-off increase in the V phase, around 2050 BP, with values of 3.5% and 0.2, respectively, and reason C / N of 17.3 and was related to change in sea level. The BG2 showed higher values compared to BG1.The base, around 810 years BP, at the top, the major fluctuations were in recent layers with values between 2.0% and 5.3% carbon, and between 0.19% and 0.51% nitrogen and C / N ratio between 9.4 and 11.7. The lignin ranged from 0.63 to 46.76 mg. 100 mg CO-1 in BG1 0.04 to 2.9 mg in BG2 mg. 100 CO-1, confirming the presence of vascular plant material allochthonous. The ratio of the phenolic groups (S/V and C/V) showed higher values of the reasons S / V on the C / V. The predominance of material from the soil in the upper stages and enriched by the remains of vascular plants in the base layers were evidenced by diagenetic indexes (Ad / Al)V and 3,5Bd / V, and indicated the intensification of erosion and larger soil loss by runoff in recent layers. Atypically in the period of about 2050 BP has identified high amount of material preserved, characteristic of vascular plants remains. During the last century the largest carbon accumulation rates, nitrogen and lignin were reported and were related to changes in land use due to intensification of the urbanization process that took place in the regions of influence of both BG1 and BG2 sedimentary profiles. Initially, the increase in carbon flux was accompanied by lignin. However, from the 90s, this behavior did not continue in the inner region of the Bay, with an increase in carbon flux without it participation of lignin. In the input of the same bay it has been observed since 2000, highlighting higher values for lignin accumulation rates, and especially in 2005 when there was a sudden increase in lignin without increasing carbon. The presence of lignin phenols found in different concentrations means that the contribution of organic matter allochthonous source exists, however the same may suffer various dilution rates and degradation during the transport and deposition and therefore can be found at many differentiated concentrations. For recent sedimentary layer on top of the profiles, BG1 and BG2, lignin flow decreases and the flow C increased, indicating that the vascular organic matter contribution for the two environments were lower

Present organic carbon fluxes from an upland peat catchment were quantified through measurement of in-situ direct and indirect greenhouse gas fluxes. To predict future greenhouse gas (GHG) fluxes, peat from eroded (E) and uneroded (U) site of an upland peat catchment was characterized.Composition of peat from E and U sites at the Crowden Great Brook catchment, Peak District Nation Park, UK that was characterized by Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC-MS) at 700 oC. Pyrolysis products of the peat were then classified using the Vancampenhout classification into 6 compound classes - viz. aromatic and polyaromatic (Ar), phenols (Ph), lignin compounds (Lg), soil lipids (Lp), polysaccharide compounds (Ps) and N-compounds (N). There was no significant difference in the composition between the eroded and uneroded sites within the study area or between peats from different depths within each site. Nevertheless, there was a significant difference between sites in the proportions of Sphagnum that had contributed to the peat. Pyrolysis products of the peat were also classified into pedogenic (Pd) and aquagenic (Aq) OC – the mean percentage of Pd in both eroded and uneroded peats was 43.93 ± 4.30 % with the balance of the OC classified as Aq.Greenhouse gas (GHG) fluxes were quantified directly by in-situ continuous measurement of GHG was carried out at the E and U sites of the catchment using a GasClam: mean in-situ gas concentrations of CH4 (1.30 ± 0.04 % v/v (E), 0.59 ± 0.05 % v/v (U) and CO2 (8.83 ± 0.22 % v/v (E), 1.77 ± 0.03 % v/v (U)) were observed, with both the CH4 and CO2 concentrations apparently unrelated to atmospheric pressure and temperature changes. Laboratory measurements of ex-situ gas production - for both CH4 and CO2 this was higher for U site soils than for E site soils. At the U site, maximum production rates of both CH4 (46.11±1.47 mMol t-1 day-1) and CO2 (45.56 ± 10.19 mMol t-1 day-1) were observed for 0-50 cm depth in soils. Increased temperature did not affect gas production, whilst increased oxygen increased gas production. The CH4/CO2 ratios observed in-situ are not similar to those observed in the ex-situ laboratory experiments; suggest that some caution is advised in interpreting the latter. However, the maximum OC loss of 2.3 wt. % observed after 20 weeks of ex-situ incubation is nevertheless consistent with the long-term degradation noted by Bellamy et al (1985) from organic-rich UK soils. Indirect greenhouse gas (GHG) fluxes were quantified through the mass flux of suspended organic carbon (SsOC) drained from studied catchments. The SsOC was quantified by interpolating and rating methods. Unfiltered (UF) organic carbon (OC) fluxes in 2010 were calculated to be 8.86 t/km2/yr for the eroded sub-catchment and 6.74 t/km2/yr for the uneroded sub-catchment. All the rating relationships have a large amount of scatter. Both UF OC and <0.2 µm fraction OC are positively correlated with discharge at the eroded site, whilst there is no discernable relationship with discharge at the uneroded site. SsOC is dominated by Pd type OC (95.23 ± 10.20 % from E; 92.84 ± 5.38 % from U) far more so than in sources of the peats, suggesting slower oxidation of Pd (cf. Aq) OC.