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A intensificação de extremos climáticos, o aumento da demanda, e a falta de um planejamento integrado dos recursos hídricos no Brasil vêm se tornando mais evidente ano após ano. No ano de 2014, deparamo-nos com cheias nas regiões Norte e Sul, enquanto o Sudeste e Nordeste sofrem com deficiências hídricas severas. A bacia do rio Paraíba do Sul também apresentou níveis muito abaixo do normal, caracterizando uma estiagem extrema. O objetivo deste trabalho foi avaliar a segurança hídrica desta bacia utilizando modelagem hidrológica, considerando os efeitos das mudanças de uso e cobertura da terra e no clima, o aumento da demanda nos centros urbanos e as transposições. As análises de extremos hidrológicos indicam uma redução nas vazões no primeiro período de simulação e um aumento no segundo. Todos os cenários apontam um aumento na intensidade e na frequência dos períodos de estiagens comprometendo ainda mais os usos das águas da bacia.

Devido à complexidade dos múltiplos usos da Bacia Paraíba do Sul, sua representação na modelagem hidrológica requer levantamento in loco das suas instalações hidráulicas e das estações fluviométricas. Visto isso, este trabalho se objetivou em realizar uma análise exploratória pela bacia, visitando pontos de monitoramento do nível da água e o levantando de dados para representação no modelo hidrológico, como a largura dos cursos d´água. Também foram observadas as usinas hidrelétricas e estações elevatórias para transposição na bacia, seu funcionamento, localização da tomada dágua e vertedores. Foi observado que a grande extração de água realizada pelo sistema Guandú e o possível assoreamento do canal até a sua foz alteram as características do canal, prejudicando também as seções com estações de monitoramento fluviométrico.

Access to drinking water is recognized as a human right, meaning that it is necessary to guarantee its universal and equitable access. Since analyzing only the average access rates to drinking water may obscure inequalities, studies have adapted socioeconomic inequalities indices to assess disparities. This research evaluated the Safe Drinking Water Access Index (SDWA) and inequalities access in all Brazilian municipalities using microdata from the 2010 Demographic Census. The inequalities were analyzed adapting indices derived from the Lorenz curve (Gini index, concentration coefficient and dissimilarity index). The results showed that the lowest SDWA rates and the highest inequality index values occurred in the north and northeast regions. The municipalities with significant inequality indexes values were rural with reduced gross domestic product (GDP) per capita. It was possible to punctuate municipalities that do not fit these rules but still need attention to safe water access guarantee. The amplitude of inequality index results reveals significant inequalities in the same regions or SDWA ranges. The inequalities in safe drinking water access were made more evident by the adapted Gini Index. This research contributes to the literature with an unprecedented analysis of Brazil and could be adapted to other countries and replicated to assess inequalities in sanitation access.

 O Nordeste Paraense sofreu profundas mudanças no decorrer dos seus ciclos de ocupação. Nessa região, a conversão de floresta para outras classes de uso e cobertura da terra ocorre há centenas de anos. Com o advento do Sensoriamento Remoto, é possível quantificar essas mudanças. Nesse sentido, o objetivo do estudo foi analisar a dinâmica da paisagem de três bacias hidrográficas no Nordeste Paraense entre 1985 e 2019 e as implicações dessas mudanças nas classes de formação florestal e mangue. A metodologia adotada abrangeu ferramentas associadas às geotecnologias no subsídio de uma análise integrada no âmbito das bacias hidrográficas. Os resultados evidenciaram uma conversão de floresta para pastagem proporcional à área do município de Castanhal/PA (aproximadamente 1.000 km²). A maior faixa de alteração ficou concentrada nas áreas de nascentes das bacias hidrográficas, como o expressivo aumento de 159% do número de manchas da classe formação florestal (de 2547 para 6604); a redução da média da área de mancha de formação florestal de 121,9 para 31,9 ha; e a redução do percentual de núcleo dessa classe de 33,7 para 16,2%. Por outro lado, não foram evidenciadas mudanças significativas na classe de mangue na área de estudo. Assim, as medidas de conservação e recuperação de áreas importantes para a manutenção dos ecossistemas costeiros e sistemas hídricos locais devem ser priorizadas pelos tomadores de decisão.

The United Nations Sustainable Development Goals (SDGs) include social and ecological goals for humanity. Navigating towards reaching the goals requires the systematic inclusion of perspectives from a diversity of voices. Yet, the development of global sustainability pathways often lacks perspectives from the Global South. To help fill this gap, this paper introduces a participatory approach for visioning and exploring sustainable futures – the Three Horizons for the Sustainable Development Goals (3H4SDG). 3H4SDG facilitates explorations of (a) systemic pathways to reach the SDGs in an integrated way, and (b) highlights convergences and divergences between the pathways. We illustrate the application of 3H4SDG in a facilitated dialogue bringing together participants from four sub-regions of Africa: West Africa, Central Africa, East Africa, and Southern Africa. The dialogue focused on food and agricultural systems transformations. The case study results incorporate a set of convergences and divergences in relation to the future of urbanization, population growth, consumption, and the role of agriculture in the African economy. These were subsequently compared with the perspectives in global sustainability pathways, including the shared socioeconomic pathways (SSPs). The study illustrates that participatory approaches that are systemic and highlight divergent perspectives represent a promising way to link local aspirations with global goals.

The Caatinga biome is the largest dry tropical forest region in South America as well as one of the most vulnerable regions in the world to the climate changes forecast for this century. Climate forecasts for the biome include increased air temperature, reduced rainfall and aridization. This biome does not have a homogeneous landscape; instead it has several rainforest enclaves. This article describes a study to model the potential distribution of four epiphytic cactus species (Epiphyllum phyllanthus (L.) Haw., Rhipsalis floccosa Salm-Dyck ex Pfeiff., Rhipsalis lindbergiana K. Schum and Rhipsalis russellii Britton & Rose.) in the biome under future climate scenarios and traces out a prognosis for the enclaves and the biome. For that purpose, we used the MaxEnt modeling method, considering two future time intervals (2041-2060 and 2061-2080) and the interval 1961-1990 for the current situation, with the RCP4.5 and 8.5 scenarios. The projections for future potential distribution showed a spatial contractions greater than 88% found in the areas of high potential presence for the target species throughout the biome and in all the scenarios. The results strengthen the expectation of aridization in the Caatinga biome, with the loss or shrinkage of rainforest enclaves as time progresses.

This study examines how land tenure constrains Brazils ability to meet its deforestation control and forest restoration goals in its Amazonia biome. Our findings are based on an updated assessment of land tenure and land use in the region. Between 2019 and 2021, 44% of deforestation in Amazonia occurred in private lands, while forest removal in settlements ranged from 31% to 27% of the total. Deforestation in undesignated public lands increased from 11% in 2008 to 18% in 2021. Deforestation is highly concentrated, with 1% of properties accounting for 82.5% of forest cuts in 2021. In Amazonia, there is considerable non-compliance with the legal reserve provisions set by Brazils Forest Code. Legal reserve deficits in private lands sum up to 18.17 Mha (million hectares), compared with 12.49 Mha of legal reserve surpluses. Even if all forest surpluses are offered in the forest credits market set in the Forest Code, farmers still need to restore 5.67 Mha to comply with the law. Large-scale cattle ranchers have a legal reserve deficit of 10.35 Mha (34% of their area). Most crop farming occurs in medium and large properties (4.63 Mha) with a large proportion of legal reserve deficits (45%). Given the political power and financial resources of large ranchers and crop producers, Brazil faces major challenges in inducing these farmers to meet their legal obligations. Therefore, Brazil needs to combine robust command-and-control strategies with market-based policies to achieve its deforestation and forest restoration goals. The government should tailor forest protection and restoration policies to the needs of different landowners, considering their land use practices, technical capacity, and financial resources.

The Digital Terrain Model (DTM) is an important product used in geosciences, but its extraction in dense forest areas is still a challenge. One of the major difficulties in extracting a DTM via remote sensors is in dense forest areas, as the generated information becomes degraded due to the fact that the most commonly used techniques can only measure canopy elevation and not terrain elevation, limiting cartography in areas such as the Amazon. The most appropriate technique for extracting a DTM is airborne LiDAR (Light Detection And Ranging), but there are limitations of time and cost for large areas. P-band radar waves have a great capacity for penetrating through dense vegetation, making it a promising tool for digital terrain modeling in forested areas. This technique was used for the latest update of the cartography of the Amapá state (Brazil). This article aims to evaluate the overall quality of a DTM produced using airborne P-band radar interferometry in relation to LiDAR data (used as a reference) in 4 regions of the Amapá state, using various criteria. In addition to the visual comparison confirming the general similarity of the two products, the difference in terms of elevation and slope was evaluated, with an average error in elevation of-0.52 m, while having a standard deviation and average RMSE below 3 meters, with a difference in slope of approximately-4° and a standard deviation and average RMSE of 4.74° and 6.14°, respectively. This study provides an estimate of the accuracy of P-band radar DTM, both in terms of elevation and slope, which are essential variables for characterizing landforms.

The vertical structure of forests provides important parameters for estimating aboveground biomass (AGB) and it can be measured by lidar sensors. The Global Ecosystem Dynamics Investigation (GEDI) full-waveform lidar sensor collects data systematically over the Earths surface from the International Space Station. Since GEDI became operational, it has collected billions of ~25-m diameter footprints. This massive dataset has been used to create higher level gridded and non-grided products. However, GEDIs ~25-m footprints can be subject to errors associated with effects of geolocation, terrain slope, and beam sensitivity, among others, which are likely transferred to the downstream products. This study aims to (1) evaluate the effect of beam sensitivity and terrain slope on the accuracy of relative heights (RH) of GEDI product L2A version 2 through comparison with discretereturn airborne lidar data collected over transects in the Brazilian Amazon Forest biome, (2) assess GEDIs geolocation uncertainty and investigate its combined effects with beam sensitivity and terrain slope, and (3) reevaluate beam sensitivity and terrain slope effects on the GEDI L2A RHs using footprints that were geolocationadjusted through a simple novel approach. The analysis separates GEDI footprints by acquisition time, i.e., daytime, nighttime, and combined (all-data). The discrete-return airborne lidar point clouds are used to derive terrain slope within the GEDI footprints and to simulate GEDI waveforms and derive RHs comparable to the GEDI L2A product. Results indicate that terrain slope only causes significant effects on GEDI data collected during daytime because solar radiation affects waveform signal-to-noise ratio. Beam sensitivity causes significant effects on nighttime and all-data GEDI L2A RHs. If geolocation uncertainty is considered, the effects of beam sensitivity and terrain slope have just minor changes. Geolocation-adjusted data continue showing significant effects on nighttime and all-data RH differences caused by beam sensitivity but produce unbiased results. This study improves the understanding of how beam sensitivity, terrain slope, and their combined effect with geolocation uncertainty may affect the GEDI L2A RH collected over the Brazilian Amazon forest during daytime and nighttime.

The joint effects of climate change and landscape fragmentation to the genetic viability of isolated populations has barely been addressed for the Atlantic Forest fauna. Therefore, this work explored the potential habitat suitability for the southern muriqui (Brachyteles arachnoides), by modeling climate change, landscape fragmentation, and genetic diversity loss of the species. Maxent was used to model its potential distribution in 2050, with two climate change scenarios. A land use and land cover change model was applied to describe current and future forest fragmentation patterns, and a Population and Habitat Viability Analysis (PHVA) was used to describe the retention of genetic diversity of the southern muriqui. Although PHVA modeling provided a low risk of extinction of the southern muriqui, climate change and fragmentation could result in the loss of >65% of the suitable forest patches, and reduce the habitat suitability to only 11% of the potential distribution area, which could lead to future genetic diversity loss and decreased capacity of self-sustained populations. In both climate change scenarios, the suitable areas for the southern muriqui in Paraná and Rio de Janeiro states will decrease more drastically. Areas where the primate occurs in the interior of São Paulo and Rio de Janeiro states will disappear or be climatically disconnected from the core potential habitat. Alike preventing further deforestation, Atlantic Forest restoration actions are needed to connect the viable populations for compensating the projected land use and climate change impacts to the long term persistence of the southern muriqui.

In Brazil, conservation priority zones, in spite of their key role in preserving natural vegetation and its environmental resources are frequently located outside the country’s public network of protected areas (PAs). Here we present the first study on land-use impacts inside Brazil’s unprotected (i.e. outside PAs) Cost-Effective conservation priority Zones (CEZs), for the period 2020-2050. CEZs are conservation priority zones that had experienced low levels of human impact in 2020. In this study, we consider various governance scenarios, including different deforestation control and native vegetation restoration policies. To this end, a land-use change model is combined with a downscaling method to generate natural vegetation cover projections at a 0.01? resolution. Results, which include the effects of climate change on the expansion of the Brazilian agriculture, project native vegetation losses (through deforestation) or gains (through restoration) inside unprotected CEZs. If the current pattern of disregard for the environment persists, our results indicate that a large share of the native vegetation inside Brazil’s CEZs is likely to disappear, with negative impacts on biodiversity preservation, green-house gas emissions and ecosystem services in general. Moreover, even if fully implemented and enforced, Brazil’s current Forest Code is insufficient to adequately protect CEZs from anthropization, especially in the Cerrado biome. We expect that this study can help improving the conservation and restoration of CEZs in Brazil.

The Amazon is one of the most important tropical forests in the world because it is a key in the regulation of the global climate. It is the world’s largest rainforest, where interactions between the forest and the atmosphere are fundamental to rainfall throughout South America and have an indirect effect on all the regions around the world. Furthermore, the Amazon region may be a source of aerosol that will act as cloud condensation nuclei (CCN). During the rainy season over the Amazon region, in which intense convective activity associated with the South America Monsoon System (SAMS) prevents fires, the primary sources of aerosols include biogenic emissions, dust from the Sahara Desert, and emissions from burning biomass transported from Africa. Besides that, the downward transport of aerosols from the upper troposphere (UT) has been considered a source of particles to the lower troposphere. The particles in the UT over the tropics region have been one of the largest aerosol reservoirs in the atmosphere, which could be from primary aerosols, such as dust, organic carbon and black carbon or secondary aerosol formed by trace gases in the free troposphere. The existence of an aerosol layer at the tropopause level has been observed during June, July, and August in Asia and North America (Asian Tropopause Aerosol Layer – ATAL and North American Tropopause Aerosol Layer – NATAL, respectively) associated with the deep convection of the Monsoons System. Therefore, the aerosol enhancement in the UT and lower stratosphere (LS) and the formation of an aerosol layer over the Amazon region associated with the deep convection of the SAMS during the austral summer are investigated. In the past, field campaigns over South America (SA) (GoAmazon2014/5 experiment) showed aerosol enhancement in the UT. They suggested that new aerosol particles are formed in the UT from biogenic volatile organic material that goes up by upward transport associated with the deep convection. The enhancement of aerosol backscatter values over SA is observed from October to January; it gradually decreases during the following months. The aerosol backscatter inferred from MERRA-2 Reanalysis showed a maximum value of the 2.24×10-5 km-2sr-1 over the Amazon during November and December. The results showed the first evidence of the existence of the South American Tropopause Aerosol Layer (SATAL) that covers the tropical SA and vertically extends up to 80hPa (approximately 18 km), similar to ATAL, and NATAL. The aerosol backscatter inferred from MERRA-2 reanalysis was validated using the attenuated backscatter by CALIOP from CALIPSO satellite. However, field campaigns such as the CAFE-BRAZIL campaign (Chemistry of the Atmosphere: Field Experiment in Brazil), which will be during December/2022 and January/2023 using the HALO (High Altitude Long Range Aircraft) aircraft, are necessary to study the formation of SATAL.