Teses em Ciências Ambientais (Doutorado) - PPGCA/IG
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Item Acesso aberto (Open Access) Análise da dinâmica da transição do regime de fogo na Amazônia brasileira(Universidade Federal do Pará, 2023-06-21) TAVARES, Paulo Amador; FERREIRA, Joice Nunes; http://lattes.cnpq.br/1679725851734904; https://orcid.org/0000-0002-4008-2341; BARLOW, Bernard Josiah; http://lattes.cnpq.br/8559847571278134The Amazon biome has undergone significant changes in land use and land cover, and it is also being affected by global climate change. Consequently, the fire occurrence has become more frequent in the Amazon. Therefore, it is important to understand how the fire regime in this region occurs and its interactions with land use and climate. For these reasons, this study analyses the fire transition in the Brazilian Amazon. In Chapter 1, we investigated the temporal fire transition in the Brazilian Amazon, considering changes in land use and forest cover. We collected annual data on fire occurrence, forest cover, deforestation rates, and soybean cultivation areas. Generalized linear mixed models and linear models were used to analyse the data and identify the key factors influencing this transition. We found that there is a fire transition process in the forest, and a quadratic model provided a better prediction of fire occurrence behaviour. Furthermore, the peak of fire occurrence is shifting towards more forested landscapes over time. Deforestation rates and the expansion of cultivation areas were found to be related to this transition, with deforestation having a greater impact on fire occurrence and cultivation expansion being more relevant in predicting the transition to more forested areas. In Chapter 2, we investigated the fire transition in forest landscapes of the Brazilian Amazon, aiming to understand how this transition occurs and which variables best explain the process. We used Latent Trajectory Analysis (LTA) and generalized linear mixed models to identify latent trajectories representing different patterns of land use over time. Two main latent trajectories were identified: the "Consolidated" trajectory, characterized by a longer history of deforestation, and the "Transition" trajectory, characterized by a more recent land occupation pattern. Forest cover and deforestation were the main predictors of forest fires in both trajectories, followed by water deficit. Mechanized agriculture did not show significant influence on either trajectory. An increase in burned forest areas was observed from 2015 onwards in both trajectories. Overall, these findings highlight the importance of the fire transition in the Brazilian Amazon and its relationship with land use changes and forest cover. They underscore the need to develop public policies that strengthen forest cover through initiatives like forest restoration and reduce deforestation in the Amazon region to ensure biodiversity conservation and carbon stocks.Item Acesso aberto (Open Access) Efeitos das mudanças de uso e cobertura da terra na paisagem e nos serviços ecossistêmicos no leste da Amazônia(Universidade Federal do Pará, 2023-05-29) PEREIRA, Fabiana da Silva; VIEIRA, Ima Célia Guimarães; http://lattes.cnpq.br/3761418169454490; https://orcid.org/0000-0003-1233-318XIn the Brazilian Amazon, the conversion of large forest areas, mainly for the expansion of agricultural activities and urban areas, has led to the loss and fragmentation of ecosystems.These changes alter ecosystem processes and functions and may affect the provision of several ecosystem services essential for human well-being and economic activities. In this context, the analysis of the effects of these changes on the landscapes and ecosystems in the Amazon region is essential to better understand the impact of these anthropogenic modifications on ecosystems services in terms of economic, ecological and social aspects. This thesis was designed to (1) quantify the impacts of land use changes on the economic value of ecosystem services in the eastern Amazon; (2) analyze the effects of habitat loss and fragmentation on the provision of ecosystem services; (3) evaluate the perception of local traditional communities about ecosystem services in order to verify which factors influence the way they identify and perceive ecosystem services and their main threats. The results show that in the 36 years analyzed there was a considerable loss in the economic value of ecosystem services provided by the forest areas, however the increase in agricultural areas has resulted in a positive balance, as the associated ecosystem services, mainly food, have a high value. In addition, forest ecosystems are smaller and increasingly fragmented and isolated, which has degraded habitat quality in the landscape and reduced carbon stocks in the region. Deforestation and illegal mining were perceived by local communities as the main threats to the provision of several ecosystem services. The most important ecosystem services identified by the communities are related to the provisioning category, such as food, wood products and medicinal plants, as well asregulating services. These results highlight the importance of assessing ecosystem services from different perspectives, in order to provide more robust information to base the development of conservation strategies, management and land use planning, as well as financial incentive strategies for ecosystem conservation or restoration.Item Acesso aberto (Open Access) Impacto das queimadas em área de floresta no sul da Amazônia: uma reflexão ensaística sobre a precificação de carbono(Universidade Federal do Pará, 2023-10-16) SILVA, Simone Nazaré Rodrigues da; VITORINO, Maria Isabel; http://lattes.cnpq.br/4813399912998401; https://orcid.org/0000-0003-3253-5301Tropical forests are important global climate regulators. They store notable amounts of carbon in their living biomass and maintain a delicate biosphere-atmosphere relationship. Exogenous and endogenous factors need to be in perfect harmony for this relationship to work properly. Carbon cycling in the Amazon has been extensively studied due to changes in CO2 concentrations globally, in soil, water, and mainly in the atmosphere. This research aims to contribute by identifying anthropogenic disturbances (burning of forest biomass) and their influence on the net exchange of CO2 in a semi-deciduous forest area south of the Amazon basin. In situ micrometeorological measurements, located 50 km NE of Sinop-MT, are used to estimate the CO2 absorption potential under polluted (AOD ≫ 0.10) and unpolluted (AOD ≤ 0.10). Limitations, uncertainties, weaknesses, and physiological optima are determined and used as key subsidies for approaches concerning carbon pricing in Brazil. Remote orbital data from the MODIS sensor (AODm) and surface data from the AERONET 2.0 system (AODa) given a regional view of the impacts of the fires on the flow of solar radiation. We have used a long series of AODa measurements between 1997 and 2017 in determining a clear-sky solar irradiance model. Here, we’ve observed reductions and increases in %NEE for given pollution loads (AOD), relative irradiance f, and solar zenith angle (SZA). The results show a 40 % in f consistent with a significant increase in pollution loads (AODa) from 0.10 to 5.0 nos at 500 nm. We also observed an average increase of 35-70 % in NEE flux for AODa pollution levels above 1.25. We’ve attributed these increases to the increase of 40-60 % in the diffuse fraction of solar radiation (P AR(D)f ) about the direct fraction (SWi) due to the impact of Aerosols Organic emitted during biomass burning (BBOA). A statistically significant reduction and increase in biophysical variables was also observed, such as leaf canopy temperature (LCT ) and Vapor Pressure Deficit (V PD), respectively. An average increase of ∼ 3.0 ◦C and 10-15 % reduction in LCT and Tair was found under densely smoky sky conditions (AOD a ≫ 0.10). These results are useful in obtaining new calibration coefficients and new physical parameterizations of processes poorly represented in current numerical systems, such as the photosynthetic responses of semi-deciduous forests to regional carbon cycling in the Amazon. These findings also guide public policies for preserving the Cerrado-Amazon Forest ecotone and other pantropical ecosystems. We have prepared an essay highlighting the weaknesses and unfeasibility of political actions aimed at pricing carbon and ecosystem services, such as the sequestration of CO2. To this end, law 2,187/2009 (National Climate Change Policy) and PL-528A/2021 (Regulation of the Brazilian Emissions Reduction Market) are analyzed. As a result, it indicates the failures of the law above and refutation. It discusses unfeasibility, pointing out feasible solutions for new forms of exploitation, contrary to this mercantile logic that neglects the peculiarities and resilience of Amazonian ecosystems, supported by the idea of exploiting natural resources as a means unique for economic development and progress, thus hiding the current ecological crisis in which we live.Item Acesso aberto (Open Access) Impactos das mudanças climáticas e do desflorestamento sobre a flora arbórea da Amazônia(Universidade Federal do Pará, 2018-11-30) GOMES, Vitor Hugo Freitas; STEGGE, Hans ter; http://lattes.cnpq.br/7778964226916459; VIEIRA, Ima Célia Guimarães; http://lattes.cnpq.br/3761418169454490Amazonia has an incredible biodiversity, shaped over millions of years. In recent millennia the climate in the region has become more humid, increasing the availability of suitable habitat for forest species and influencing its distributions and the expansion of the forest in this period. However, human influences on climate and land use have led to a reduction in the habitat of many species in the region, and projections show an intensification in the future with impacts potentially negative on the richness and distribution of Amazonian biodiversity. In addition, there are several knowledge gaps on how climate and land use has shaped and will shape the Amazonian rainforest, and the wide variety of methods available for such analysis also raises questions on the best methodological practices for studying an area as large and diverse as Amazonia. Understanding the origin, maintenance and loss of biodiversity has a profound importance for future human life. This thesis addresses some of the knowledge gaps on these topics, comparing methods of estimating richness and distribution of species of the Amazonian rainforest at different time scales. This study is an interdisciplinary research that relates aspects of different scientific areas to understanding the consequences of the two main threats to Amazonian biodiversity attributed to climate change and deforestation. The study was supported by a cooperation between the Naturalis Biodiversity Center – The Netherlands and Museu Paraense Emílio Goeldi – MPEG on a Sandwich Doctorate Scholarship – SWE (CNPq Prossess 203102/2015-0). Furthermore, the study is part of the INCT project Biodiversidade e Uso da Terra na Amazônia (Biodiversity and Land Use in Amazonia) (CNPq Prossess 574008/2008-0), coordinated by MPEG, which is dedicated to the study of biodiversity and Amazonian landscape, aiming to understand environmental and social consequences of different land uses, providing scientific bases for sustainable economic practices and support for public policies for Amazonia.Item Acesso aberto (Open Access) Impactos das mudanças climáticas na biomassa florestal Amazônica: Previsão de perda e estratégias de conservação prioritárias para o potencial de biomassa sob as mudanças climáticas(Universidade Federal do Pará, 2024-04-25) CAMPOS, Mayara Soares; ANJOS, Luciano Jorge Serejo dos; http://lattes.cnpq.br/0244738999001686; https://orcid.org/0000-0002-3270-6679; ADAMI, Marcos; http://lattes.cnpq.br/7484071887086439; https://orcid.org/0000-0003-4247-4477The study addresses the influence of climate change on Aboveground Biomass (AGB) in the Amazon, examining both reduction forecasts and potential increases under different climate scenarios until the end of the century. Using AGB data (GEDI) and climate variables from Global Circulation Models (GCM‘s) and Shared Socioeconomic Pathways (SSP‘s), the research employs Geographically Weighted Regression (GWR) to explore spatial patterns of AGB distribution. The results point to a significant decline in AGB, with estimated reductions ranging from 14.2% to 32.1%, where the average vegetation density could drop to 177.61 Mg/ha-1 by 2040 and 140.43 Mg/ha-1 by 2100, indicating a decrease in the forest's carbon sequestration capacity, especially in the northeast, central-east, west, and south regions of the Amazon. Conversely, potential AGB gains were identified in specific areas of the Brazilian Amazon, mainly in the northwest and southeast regions, covering the Negro, Xingu, and Tapajós river basins, under both future scenarios. Indigenous Lands (TI‘s) emerge as crucial for conservation, exhibiting greater AGB gains in both scenarios analyzed. This study underscores the importance of mitigation strategies and the role of protected areas in maintaining Amazon resilience in the face of future climate adversities. By highlighting areas of potential AGB increase, it emphasizes the significance of preserving and valuing protected areas and TI‘s as fundamental strategies to address environmental and climate challenges. This approach not only focuses on mitigating AGB loss but also recognizes the potential of specific regions to positively contribute to Amazon resilience amid future climate changes. Therefore, this study is of great importance for both science and public policy formulations, as it provides an analysis of the impact of AGB climate change in the Amazon, essential in the carbon cycle and, by extension, in mitigating global climate change. By identifying vulnerable regions and those with potential AGB increase, it highlights the urgency of targeted conservation strategies.Item Acesso aberto (Open Access) Produtividade de citrus na Amazônia Oriental: relações com o clima atual, risco socioambiental relativo aos eventos extremos e modelagem dos impactos das mudanças climáticas futuras(Universidade Federal do Pará, 2023-05-31) DIAS, Thaiane Soeiro da Silva; RUIVO, Maria de Lourdes Pinheiro; http://lattes.cnpq.br/9419564604488031; HTTPS://ORCID.ORG/0000-0002-6222-5534; SOUZA, Everaldo Barreiros de; http://lattes.cnpq.br/6257794694839685; https://orcid.org/0000-0001-6045-0984In the context of the agricultural frontier within the Amazonian territory, the production of citrus (lime and oranges) has been relevant in socioeconomic and environmental terms. In this thesis, three different scientific approaches were developed to elucidate: i) the relationships between citrus productivity and climate variability (rainfall and air temperature) and deforestation patterns in eastern Amazonia during the last decades; ii) the socio-environmental risk of citrus productivity due to extreme precipitation events in eastern Amazon; and iii) the impacts of different future scenarios of climate change on the distribution of potential areas of occurrence of the species Citrus sinensis over the Legal Brazilian Amazon. The results showed evidence that natural factors (climate variability and extreme precipitation events) and anthropic factors (deforestation) directly influence citrus productivity in several areas of eastern Amazonia. In addition, projections indicate that climate change can negatively impact the distribution of the main occurrence areas of the Citrus species throughout the Brazilian Legal Amazon.Item Acesso aberto (Open Access) Uso racional da água em plantios de limão tahiti, citrus latifolia (Yu. Tanaka), na Amazônia Oriental.(Universidade Federal do Pará, 2022-07-18) SILVA JUNIOR, Alberto Cruz da Silva; SOUSA, Adriano Marlisom Leão de; http://lattes.cnpq.br/4371199443425884; https://orcid.org/0000-0002-2809-5318; RUIVO, . Maria de Lourdes Pinheiro; http://lattes.cnpq.br/9419564604488031; https://orcid.org/0000-0002-6222-5534The need for a more rational use of water resources requires changes in society's behavior in favor of a more sustainable use of natural resources. This interdisciplinary research investigated how soil-plant-atmosphere interactions modify the energy balance and evapotranspiration demand in Tahiti lime plantations and how these variations interfere in the water sustainability of the crop in the eastern Amazon. The specific objectives are to evaluate the seasonality of the energy balance and the water demand of the Tahiti lime and to define parameters that contribute to the efficient use of water in irrigation in the Eastern Amazon. In addition, calculate the green, blue and gray water footprints of lemon production in the region and compare with the main producing regions in Brazil. With the results of this thesis, it is expected to contribute to generate a solid base of information that allows optimizing the replacement of water in irrigation and quantifying the size of human appropriation of this natural resource in the areas of cultivation. Meteorological data were monitored: air temperature at two levels above the canopy, relative air humidity, extraterrestrial radiation, wind speed and direction, rainfall and heat flux to the ground; soil data: granulometry, chemical fertility, bulk density and volumetric soil water content; and data inherent to the plant: effective depth of the root system, flowering, fruiting and leaf area index. We also use IBGE, INMET, ANA and MAPBIOMAS databases as a source for calculating the water footprints of tahiti lime production in 48 municipalities in 4 states, correlating their respective PH's with government water security indices and thus evaluating the sustainability of production. As main results of chapter 2 it was found that 63% of the available energy was used to produce latent heat in the wettest period, while 60% were used during the less rainy season. Sensible heat used 32% and 34% during the most and least rainy period, respectively. On the other hand, soil heat showed little variation, with an average of 5% for the entire period. The water consumption of Tahiti lime during the experiment was 1599 mm, with a daily mean of 3.70 mm day-1, while the mean value of Kc was 1.4. These results allow the adequate design of water supply protocols for culture in the main citrus pole in the Amazon region. In chapter 3, the main findings are that there is wide variability in PH among the producing municipalities, with emphasis on the states of São Paulo and Minas Gerais, where the best results were obtained. In the states of Bahia and Pará, we found high PH's associated mainly with low productivity. In general, we conclude that the seasonality of the evapotranspiration demands of the lemon crop follow specific dynamics in the Amazon region and that the water footprint was a good gauge of water appropriation during the production of tahiti lemon.