Publicações

Os marcos geodésicos (MGs) são essenciais para desenvolver projetos e obras, porém, estão sujeitos à erosão. Neste estudo, foram estimadas a perda de solo nos MGs na região sul do estado de Santa Catarina considerando dados históricos e cenários futuros de mudanças climáticas. Os resultados mostraram que a perda de solo diminuiu de 1985 a 2020, porém, houve um aumento de MGs na classe de perda de solo nula, causado pelo crescimento urbano. Para a maioria dos cenários futuros houve aumento na perda de solo de 2020 a 2100, embora com valores inferiores ao passado. Estes cenários consideraram apenas alterações de precipitação, sendo que a modelagem da mudança da cobertura do solo para o futuro poderia trazer melhorias na análise. Portanto, estudos como este podem ser usados para entender os efeitos das mudanças climáticas nos processos erosivos e apoiar a tomada de decisão para manter e aumentar a rede geodésica.

Os dados meteorológicos são amplamente utilizados em vários tipos de estudos em diversas regiões geográficas. Entretanto, sua obtenção por medições diretas através de estações meteorológicas possui distribuição espacial limitada. Para transpor essa limitação, dados de sensoriamento remoto podem ser utilizados como uma alternativa. Com o objetivo de avaliar o uso desses dados para a região do Matopiba, o presente trabalho comparou os dados de precipitação provenientes dos produtos CHIRPS e PERSIANN com os dados de estações automáticas do INMET. Para comparação, calculamos coeficiente de correlação de Spearman e o índice de concordância de Willmott modificado. Os resultados mostraram que os dados CHIRPS e PERSIANN são coerentes e podem ser usados como alternativa aos dados de estação meteorológicas, com melhor desempenho para os dados de precipitação acumulada.

Forest degradation is a major issue and a key component of tropical forests and carbon emissions. In this study, we use repeated Airborne Laser Scanning (ALS) data to quantify carbon losses in degraded forests due to logging at the Mato Grosso state rainforests. We identified logged areas using Planet Norway’s International Climate and Forests Initiative (NICFI) satellite imagery and estimated aboveground carbon density (ACD) and changes (ΔACD) using canopy structure derived from ALS data acquired before and after the logging. Logging caused carbon losses between 16-35% of the original ACD, but also as high as 89% in heavily disturbed areas. Our findings bring estimates to limited sites, so we recommend caution on using them for estimates of carbon loss elsewhere. Spatialized and continuous estimates should be explored in future studies connecting ALS estimates with other optical and SAR remote sensing datasets.

Here, we evaluated the combination of five satellites/sensors for improving burned area (BA) detection over the Amazon basin. Using a data set of 2,400 burn/no burn points by visual inspection in 2016, we investigated several spectral indices and ingested them into data mining algorithms to evaluate their burning area detection performance. Better results were provided with attribute selection combining Sentinel-2 (S2) and MODIS indexes (96 %), which were not significantly better than S2 indexes alone (95 %). The worst was the Sentinel-1 SAR data with 85 % accuracy. This is the first large-scale data research to evaluate the potentiality of combined temporal, spectral, and spatial resolutions for BA detection across the Amazon.

A compreensão da taxa de crescimento da biomassa acima do solo (BAS) em florestas sob regeneração natural é essencial para mensurar o sequestro de carbono florestal e auxiliar na mitigação das mudanças climáticas. Neste estudo, estimamos a BAS em 57 amostras de florestas secundárias amazônicas, por meio da combinação de dados aerotransportados LiDAR e hiperespectrais e modelos de aprendizado de máquinas. A idade das florestas secundárias foi determinada pela análise da série temporal de imagens Landsat de 1984 a 2017. As florestas secundárias exibiram uma taxa de recuperação de BAS de 5,7 Mg.ha-1.ano-1, calculadas por meio de regressão linear (R2 = 0,91). A integração de dados multisensores mostrou grande potencial para apoiar iniciativas de mitigação do clima.

The southeastern Amazon has recently been shown to be a net carbon source, which is partly caused by drying conditions. Drying depends on a number of factors, one of which is the land cover at the locations where the moisture has originated as evaporation. Here we assess for the first time the origins of the moisture that precipitates in the Amazon carbon source region, using output from a Lagrangian atmospheric moisture tracking model. We relate vegetation productivity in the Amazon carbon source region to precipitation patterns and derive land-cover data at the moisture origins of these areas, allowing us to estimate how the carbon cycle and hydrological cycle are linked in this critical part of the Amazon. We find that, annually, 13% of the precipitation in the Amazon carbon source region has evaporated from that same area, which is half of its land-derived moisture. We further find a moisture-recycling-mediated increase in gross primary productivity of roughly 41 Mg carbon km(-2) yr(-1) within the Amazon carbon source region if it is fully forested compared to any other land cover. Our results indicate that the parts of the Amazon forest that are already a net carbon source, still help sustain their own biomass production. Although the most degraded parts of the Amazon depend mostly on oceanic input of moisture, further degradation of this region would amplify carbon losses to the atmosphere.

The achievement of several sustainable development goals and the Paris Climate Agreement depends on rapid progress towards sustainable food and land systems in all countries. We have built a flexible, collaborative modeling framework to foster the development of national pathways by local research teams and their integration up to global scale. Local researchers independently customize national models to explore mid-century pathways of the food and land use system transformation in collaboration with stakeholders. An online platform connects the national models, iteratively balances global exports and imports, and aggregates results to the global level. Our results show that actions toward greater sustainability in countries could sum up to 1 Mha net forest gain per year, 950 Mha net gain in the land where natural processes predominate, and an increased CO2 sink of 3.7 GtCO2e yr−1 over the period 2020-2050 compared to current trends, while average food consumption per capita remains above the adequate food requirements in all countries. We show examples of how the global linkage impacts national results and how different assumptions in national pathways impact global results. This modeling setup acknowledges the broad heterogeneity of socio-ecological contexts and the fact that people who live in these different contexts should be empowered to design the future they want. But it also demonstrates to local decision-makers the interconnectedness of our food and land use system and the urgent need for more collaboration to converge local and global priorities.

The terrestrial water cycle links the soil and atmosphere moisture reservoirs through four fluxes: precipitation, evaporation, runoff, and atmospheric moisture convergence (net import of water vapor to balance runoff). Each of these processes is essential for sustaining human and ecosystem well-being. Predicting how the water cycle responds to changes in vegetation cover remains a challenge. Recently, changes in plant transpiration across the Amazon basin were shown to be associated disproportionately with changes in rainfall, suggesting that even small declines in transpiration (e.g., from deforestation) would lead to much larger declines in rainfall. Here, constraining these findings by the law of mass conservation, we show that in a sufficiently wet atmosphere, forest transpiration can control atmospheric moisture convergence such that increased transpiration enhances atmospheric moisture import and results in water yield. Conversely, in a sufficiently dry atmosphere increased transpiration reduces atmospheric moisture convergence and water yield. This previously unrecognized dichotomy can explain the otherwise mixed observations of how water yield responds to re-greening, as we illustrate with examples from China’s Loess Plateau. Our analysis indicates that any additional precipitation recycling due to additional vegetation increases precipitation but decreases local water yield and steady-state runoff. Therefore, in the drier regions/periods and early stages of ecological restoration, the role of vegetation can be confined to precipitation recycling, while once a wetter stage is achieved, additional vegetation enhances atmospheric moisture convergence and water yield. Recent analyses indicate that the latter regime dominates the global response of the terrestrial water cycle to re-greening. Evaluating the transition between regimes, and recognizing the potential of vegetation for enhancing moisture convergence, are crucial for characterizing the consequences of deforestation as well as for motivating and guiding ecological restoration.

Subpolar coastal waters are key hotspots in the global carbon cycle. However, the small-scale distribution of partial pressure of carbon dioxide (pCO2) in these environments and the physical and biological controls underlying this variability are still poorly understood. Here, we examine simultaneous high-resolution spatial measurements of wind speed and pCO(2), temperature, salinity, and in-vivo chlorophyll-a fluorescence (chl-a fluo, a proxy of phytoplankton biomass) in surface waters that were obtained during an oceanographic survey in the Argentinian Beagle Channel (subantarctic Atlantic Patagonian) in early fall 2017. The 240 km study transect (centered at 55 degrees S – 67 degrees W) was divided into two zones: (A1) The Beagle Channel innermost portion, semi-enclosed and subject to strong continental influence and (A2) its eastern outlet towards the open Southwest Atlantic. Discrete seawater samples were also collected for apparent oxygen utilization (AOU), nutrients and pH measurements. High-resolution spatial measurements revealed the persistence of pCO(2) below atmospheric equilibrium, increasing in median (interquartile range 25-75%) from 314 mu atm in the inner Beagle Channel (A1) to 348 mu atm towards the adjacent open sea (A2). A decrease in atmospheric CO2 sequestration was associated with an increase in water temperature from 9.5 degrees C to 10.7 degrees C, salinity from 30.8 to 32.5, and chl-a fluo from 2.24 to 2.91 mg m(-3) along the coastal-offshore gradient. Low AOU and nutrient levels were found in regions inside the channel. Indeed, the relationships between CO2 and temperature or salinity were significantly different from those expected from the theoretical solubility effect, indicating a dominance of metabolic over physicochemical controls on this gas. Moreover, physical factors such as vertical stratification contributed to the variable surface pCO2 values. These findings reveal the existence of short-scale spatial variability of CO2 in the Beagle Channel, improving our understanding of the multiple controls on atmospheric carbon sequestration in extensive subpolar continental shelves.

Green crimes are violations of environmental laws that aim to protect human well-being, natural resources, and ecosystems. Brazil has recorded an increase in green crimes in recent years. In this study, we used Spatial Durbin and other regression models to analyze the relationship between land use and green crime. We test whether there is a positive association between green crimes and the following land uses: urban edge areas, rural edge areas, and mixed urban uses. The results show that green crimes are spatially related to areas of high contact and exposure between human activity and the natural environment (urban and rural mixed uses), but that human presence by itself (presence of industrial activity) is not particularly associated with the occurrence of green crimes. These findings can serve to design and deploy data-driven policies and policing of green crimes.

No Brasil, os municípios de pequeno porte são afetados por impactos de desastres em diferentes níveis, diante de suas distintas características econômicas e sociais. Para a redução de danos materiais e humanos, é necessária uma abordagem que considere múltiplas dimensões de resiliência e adaptação. Nesse contexto, o objetivo da presente tese consistiu em analisar a resiliência comunitária a desastres de municípios de pequeno porte, com alto índice de desenvolvimento humano municipal, e com histórico de desastres relacionados a inundações, enxurradas, alagamentos e deslizamentos de terra. A análise foi conduzida para 213 municípios da região Sudeste, com histórico de desastres. Duas abordagens foram utilizadas: i) a quantitativa, em escala municipal, através de análises estatísticas e a construção de um índice de resiliência comunitária a desastres, que considerou as dimensões social, econômica, infraestrutura, institucional e comunitária; ii) e a qualitativa, em escala intramunicipal, que avaliou os níveis de capital social de populações afetadas por desastres dos municípios de Santos Dumont (MG) e Mongaguá (SP), obtidos por meio de questionário online. Os resultados mostraram que os níveis de resiliência comunitária têm relação direta com o desenvolvimento econômico e urbano dos municípios avaliados. Aqueles que apresentavam os menores valores de resiliência comunitária a desastres estavam associados às características de maior vulnerabilidade da população, como baixo desenvolvimento socioeconômico, domicílios precários, infraestrutura urbana insuficiente para serviços de transporte, saúde, lazer e apoio social; e implementação ineficaz de políticas públicas de desenvolvimento. Os resultados também evidenciaram que a inexistência e a diversidade de espaços de lazer que propiciem conexões sociais, podem gerar a falta de interesse da população em frequentar locais de convivência e participar de grupos de pessoas, ocasionando níveis baixos de capital social. A análise de resiliência comunitária a desastres dos municípios de pequeno porte contribui para delinear medidas de adaptação para diferentes cenários de risco de desastres.

Worldwide, disasters are recognized to be gender sensitive. Women play a vital part of disaster response efforts, developing specific knowledge and skills in contexts of threat, although the prevailing social imbalances and lower socio-economic status influence and make unequal and unfair women’s response and recover to disasters. Despite the singularities found in each disaster situation, referred to the context – significance of the moment, place, and circumstances in which people live – and the typology of hazards, there is no disagreement about the importance of strategies for disaster risk reduction be designed in association with pre-existing social and economic conditions, combined with a need to identify potential human resources and capacities to achieve safer and more resilient spaces. The overall objective of this research project was to identify whether gender inequalities present themselves as a condition of differential impact and capacities to tackle disasters in Brazil, embracing women’s roles as a window of opportunity for new ways of dealing with disasters. The first challenge to be surpassed was to identify who dies from natural hazards in Brazil. Through the analysis of the Brazilian Data Mortality of the Brazilian Ministry of Health, from 1979 to 2019, we examine the distribution of natural hazard fatalities in the national territory, their periodicity, and the number and characteristics of the affected victims. We find out lightning is the deadliest natural hazard in Brazil, but since 2010 there is a sudden increment of hydro-meteorological fatalities as consequence of very few but large-scale disasters. The number of male fatalities is higher for every category of natural hazards, and the single victims dye the most. A deep analysis of the spatial and temporal distribution of fatalities of hydro-meteorological disasters in the national territory over different periods reveals that Brazilian large-scale disasters determine Brazilian fatalities standards being January and SH summer the periods with higher number of fatalities. Territorially, the Southeast region is where most of the registered fatalities are concentrated and Rio the Janeiro State with the higher number of fatalities. Seeking to understand gender differential impact and their roles in disaster contexts we develop an intersectional analysis of Brazilian hydro-meteorological disasters from 2000 to 2019 through data mortality disaggregated by sex, age, and race. Social inequalities exist and are gender and race-sensitive in Brazil, and despite the socially constructed disparities between white men and black women, and everyone in between, over the last two decades, women have been more capable of surviving from hydrometeorological hazards. The differences in the number of fatalities between white and non-white male victims are high and unquestionable, but the differences into the Brazilian female group are subtle. This result posed the challenge to identify the factors that make certain people more capable of anticipating, responding to and surviving from disasters. Facing this challenge and in between the COVID-19 pandemic we developed the Sobrevidas©, an online platform accessible by a mobile phone created to collect data and stories from disaster survivors, with no territory frontiers. Through Sobrevidas© we recognized a few and important female victims of the 2011 Rio de Janeiros Serrana Region tragedy acknowledging the potentiality of the tool to access those community-based involved in disaster response, survival, and recover and identify women’s capabilities for a safer condition of living. We live on a planet under pressure where the conversion of ecosystem services, land use, biodiversity loss, planetary thresholds, and food, water, and energy security is at riska changing planet destabilized by human perturbation with chances of no return to its original equilibrium. The increase in frequency and intensity of extreme climate events amplifies the severity of natural hazards and, consequently, the challenges that social systems face, especially for those who already experience vulnerabilities in their daily lives. Through this thesis development, Brazilian women have proven to be more capable to survive of disasters despite all inequalities. Brazilian science, decisionmakers, and society must recognize it and empower womens grassroots initiatives and participation in decision-making on prevention, response, and recovery from disasters in an unequal society threat by global change.