Amazon Area Research Articles

Molecular characterization of Chikungunya virus recovered from patients in the Maranhão state, Brazil.

Chikungunya virus (CHIKV) is an arbovirus from the Togaviridae family which has four genotypes: West African (WA), East/Central/South African (ECSA) and Asian/Caribbean lineage (AL) and Indian Ocean Lineage (IOL). The ECSA genotype was first registered in Brazil in Feira de Santana and spread to all Brazilian regions. This study reports the characterization of CHIKV isolates recovered from sera samples of fifty patients from seventeen cities in Maranhão, a state from Brazilian northeast region and part of the Legal Amazon area. Primers were developed to amplify the partial regions coding structural proteins (E1, E3, E2, 6K, and Capsid C). The consensus sequences have 2871bp, covering approximately 24% of the genome. The isolates were highly similar (> 99%) to the ECSA isolate from Feira de Santana (BHI3734/H804698), presenting 30 non-synonymous mutations in E1 (5.95%), 18 in E2 (4.46%), and 1 in E3 (3.03%), taking the BHI3734/H804698 isolate as standard. Although the mutations described have not previously been related to increased infectivity or transmissibility of CHIKV, in silico analysis showed changes in physicochemical characteristics, antigenicity, and B cell epitopes of E1 and E2. These findings demonstrate the importance of molecular approaches for monitoring the viral adaptations undergone by CHIKV and its geographic distribution.

Main drivers of dragonflies and damselflies (Insecta; Odonata) metacommunities in streams inside protected areas in the Brazilian Amazon.

The evaluation of environmental and spatial influence in freshwater systems is crucial for the conservation of aquatic diversity. So, we evaluated communities of Odonata in streams inside and outside sustainable use areas in the Brazilian western Amazon. We predicted that these streams would differ regarding habitat integrity and species α and β diversity. We also predict that environmental and spatial variables will be important for both suborders, but with more substantial effects on Zygoptera species, considering their nature of forest-specialist. The study was conducted in 35 streams, 19 inside and 16 outside sustainable use areas. The streams outside presented high species richness, abundance, and number of exclusive forest-specialist species from Zygoptera and higher scores of habitat integrity. In contrast, one sustainable use area presented the lowest values of these metrics. Besides, we found that environmental and spatial variables were significantly associated to Zygoptera species composition, but not with Anisoptera, which can be explained by their cosmopolitan nature. Our results indicated that an interplay between environmental and spatial processes determines the structure of the metacommunities of Zygoptera. The less effective dispersal rates and narrow ecological tolerance of Zygoptera species make them more influenced by local conditions and dispersal limitation, and more sensible to habitat modifications. We highlight the importance of improving the local management of the sustainable use areas by environmental agencies, mainly on areas that are losing their capacity to maintain the aquatic fauna, and implementation of social policies toward traditional people.

Understanding the impact of mobility on Plasmodium spp. carriage in an Amazon cross-border area with low transmission rate.

Despite the large reduction in malaria incidence in the last decade, the last kilometre to elimination is often the hardest, especially in international border areas. This study investigated the impact of mobility on Plasmodium spp. carriage in people living in a cross-border area in Amazonia with a low malaria transmission rate. We implemented a longitudinal ancillary study in the French Guiana town of St. Georges de l'Oyapock, which is located on the border with Brazil. It was based on data from two transversal surveys performed in October 2017 and October 2018. Data were collected on peri-domestic mobility for food-producing activities, and longer-distance mobility in high-risk areas. Participants were screened for Plasmodium spp. carriage using PCR tests, and treated if positive. Vector density around a participant's home was estimated using a previously published model based on remote sensing and meteorological data. The association between Plasmodium spp. carriage and mobility was analysed using a generalized additive mixed model. A total of 1,192 inhabitants, aged between 0 and 92 years old, were included. Median age was 18 years in 2017 (IQR [8;35]). Plasmodium spp. prevalence in the study population was 7% in 2017 (n = 89) and 3% in 2018 (n = 35). Plasmodium spp. carriage was independently associated with i) travel to the adjoining Oiapoque Indigenous Territories in Brazil (OR = 1.76, p = 0.023), ii) the estimated vector density around a participant's home (High versus Low risk OR = 4.11, p<0.001), iii) slash-and-burn farming (OR = 1.96, p = 0.013), and iv) age (p = 0.032). Specific surveillance systems and interventions which take into account different types of mobility are needed in cross-border areas to achieve and maintain malaria elimination (e.g., reactive case detection and treatment in the places visited).

Litter stock and nutrients under different restoration methods in the eastern Amazon

Litter production contributes to soil fertility through the decomposition process, especially in Amazonian soils, which have low fertility. Amazonian ecosystems are dependent on the forest to ensure their maintenance through nutrient cycling, via litter. The objective of this work was to evaluate litter stock and nutrient content under different restoration methods in abandoned pasture areas in the eastern Amazon. The macronutrient content via litter followed the order: Ca &gt; N &gt; P &gt;Mg &gt; K &gt;Na. Calcium was the macronutrient that most returns to the soil via litter. The restoration method through silvipastoral system presented the highest values of nitrogen. The area under passive restoration proved to be the most efficient method to recover areas degraded by pasture in the eastern Amazon, due to the highest litter stock and nutrient content.&#x0D;

Evaluation of agronomic characters in corn genotypes (Zea mays L.) Safrinha in agricultural area of Amazon in the municipality of Conceição do Araguaia-PA

World agriculture faces the challenge of increasing food production, while expansion of the cultivated area is restricted. To meet this demand, it is necessary to increase the productivity of the crops, the work of genetic improvement being crucial. In this context, 20 commercial genotypes of safrinha corn were tested, in the no-till system in the rural zone of the municipality of Conceição do Araguaia-PA, with the objetive of identifying those with the best agronomic performance. The research was carried out at the João e Maria farm, in the rural area of this municipality, in the agricultural year 2021/2022, with sowing in March. The experiment adopted an experimental design of blocks at random, with 20 treatments (genotypes) and 3 repetitions. The following characteristics have been determined: plant height, ear height, number of rows per ear, number of grains per row, ear length, weight of one hundred grains and grain yield. The data were submitted to the analysis of variance by the F test and the means were compared using the Tukey test, with a significance level of 5%. The results of the research showed that, under the soil and climatic conditions in which they were assessed, the genotype KWS 0221 showed satisfactory results in relation to productivity. Genotypes KWS 0121 and KWS 0321 have also shown promising performance. Therefore, these materials are highly recommended for planting in the harvest in the southeast of Pará, due to their favorable agronomic characteristics and their adaptability in the region of the study.

Historical Projection of the Rainfall Distribution in the North Region of Brazil

From a set of primary and secondary monthly data from 1991 to 2022, the annual and seasonal climatological pattern of the North region of Brazil, where most of the Amazon Biome is located, was analyzed. An incomplete Gamma distribution model was applied to the climatological precipitation data (mm); atmospheric pressure (mb); incidence of solar radiation (kJ/m²); air temperature and dew (ºC); relative humidity (%); wind intensity (m/s) with direction and maximum gust. Data normalization techniques and spatial similarity identified different patterns and trends of precipitation in the region, with significant seasonality, especially in terms of rainfall. The highest precipitation rates occurred in the N-NW axis, inside the northern Amazonian area, while the lowest values were observed in the southern equatorial zone, on the limits of the Pará State with the Cerrado Biome. Four zones and one climate range were established: southern, central, northern west and northern east zones and extreme north area, all with significant similarity in precipitation and humidity. A trend was observed in the number of days with precipitation between 25 and 50% in the southern and central zones, and an increase in precipitation of 50 to 75% for the northern zone. The wind distribution model showed a tendency towards the presence of isotropic climate phenomena, presenting the same properties or characteristics. The results obtained are relevant to support research aimed at understanding global warming and its consequences, in addition to contributing to forest management programs, and establishing more effective protocols for cultivation in agricultural areas in the Amazon.

From everyday participation to ways of life: Development of Yurakare children in Bolivia's Amazonian area

AbstractChildren's participation in the social structure from the first stages of life shapes not only their development but also how they learn to become well‐adjusted members of their cultural environment. In the presented study, using focal‐follow and participatory observation, we depict the reality in early and middle childhood (N = 23; ages 2–7) of Yurakare children living in Bolivia's Amazonian area. We attempt to determine whether the facets of the LOPI model (Learning by Observing and Pitching in) proposed by Rogoff are represented in the everyday way of life of Yurakare children. This is the first systematic, quantitative study of children's social environment and practice in this Indigenous community. The results show that the practices of the Yurakare people are based on two things: (1) inclusion of all ages in community life, which cultivates children to engage in useful activities even while having fun; (2) the primacy of mature activities, which is in line with the LOPI model.

Goupia glabra não recupera seu estoque de madeira após um ciclo de corte de 35 anos na Amazônia brasileira: evidências de monitoramento de longo prazo em múltiplas áreas

ABSTRACT Single-rule management is often adopted for various tropical forest timber species due to limited knowledge on species-specific growth and the relationship between logging intensity and recovery time. This study provides information to support sustainable management of Goupia glabra by simulating its wood stock recovery over a 35-year period following logging using data from six areas in the Brazilian Amazon. Monitoring periods after the first harvest cycle varyed from 16 to 29 years, and logging intensity from 0.000 to 0.696 m² ha-1. Tree density of G. glabra varied from 0 to 22 trees ha-1 and dominance from 0.00 to 7.39 m² ha-¹. Frequency of tree diameters was almost evenly distributed across diameter classes, slightly higher in the first (20-30 cm) class. These parameters generated estimations of recovery rate from 12 to 85%, showing that 35 years is insufficient for trees with DBH ≥ 20 cm in all study areas to grow and replace the stock of trees with DBH ≥ 50 cm harvested during the first cycle. Minimum recovery periods from 48 to 83 years were estimated to guarantee the recovery of the wood stock in the study areas. These findings reinforce the need to adapt management rules according to the population dynamics of each timber species and each logging area, and suggest the need for changes in the current legal requirements that define forest management in the Amazon.

Characterization of larval habitats of Anopheles (Nyssorhynchus) darlingi and associated species in malaria areas in western Brazilian Amazon.

Anopheles darlingi is the most efficient vector of malaria parasites in the Neotropics. Nevertheless, the specificities of its larval habitats are still poorly known. Characterize permanent larval habitats, and population dynamics of An. darlingi and other potential vectors in relation to climate, physicochemical variables, insect fauna and malaria cases. A 14-month longitudinal study was conducted in Porto Velho, Rondônia, western Brazilian Amazon. Monthly, 21 permanent water bodies were sampled. Immature anophelines and associated fauna were collected, physicochemical characteristics, and climate variables were recorded and analyzed. Five types of habitats were identified: lagoon, stream, stream combined with lagoon, stream combined with dam, and fishpond. A total of 60,927 anophelines were collected. The most abundant species in all habitats were Anopheles braziliensis and An. darlingi. The highest density was found in the lagoon, while streams had the highest species richness. Abundance was higher during the transition period wet-dry season. There was a lag of respectively four and five months between the peak of rainfall and the Madeira River level and the highest abundance of An. darlingi larvae, which were positively correlated with habitats partially shaded, pH close to neutrality, increase dissolved oxygen and sulphates. The present study provides data on key factors defining permanent larval habitats for the surveillance of An. darlingi and other potential vectors as well as a log-linear Negative Binomial model based on immature mosquito abundance and climate variables to predict the increase in the number of malaria cases.

Malaria in areas under mining activity in the Amazon: A review.

Deforestation and high human mobility due to mining activities have been key to the increase in malaria cases in the Americas. Here, we review the epidemiological and control aspects of malaria in the Amazon mining areas. Epidemiological evidence shows: 1) a positive correlation between illegal mining activity and malaria incidence, mostly in the Amazon region; 2) most Brazilian miners are males aged 15-29 years who move between states and even countries; 3) miners do not fear the disease and rely on medical care, diagnosis, and medication when they become ill; 4) illegal mining has emerged as the most reported anthropogenic activity within indigenous lands and is identified as a major cause of malaria outbreaks among indigenous people in the Amazon; and 5) because mining is largely illegal, most areas are not covered by any healthcare facilities or activities, leading to little assistance in the diagnosis and treatment of malaria. Our review identified five strategies for reducing the malaria incidence in areas with mining activities: 1) reviewing legislation to control deforestation and mining expansion, particularly in indigenous lands; 2) strengthening malaria surveillance by expanding the network of community health agents to support rapid diagnosis and treatment; 3) reinforcing vector control strategies, such as the use of insecticide-treated nets; 4) integrating deforestation alerts into the national malaria control program; and 5) implementing multi-sectoral activities and providing prompt assistance to indigenous populations. With this roadmap, we can expect a decrease in malaria incidence in the Amazonian mining areas in the future.

A Parameterization for Cloud Organization and Propagation by Evaporation‐Driven Cold Pool Edges

AbstractWhen the negatively buoyant air in the cloud downdrafts reaches the surface, it spreads out horizontally, producing cold pools. A cold pool can trigger new convective cells. However, when combined with the ambient vertical wind shear, it can also connect and upscale them into large mesoscale convective systems (MCS). Given the broad spectrum of scales of the atmospheric phenomenon involving the interaction between cold pools and the MCS, a parameterization was designed here. Then, it is coupled with a classical convection parameterization to be applied in an atmospheric model with an insufficient spatial resolution to explicitly resolve convection and the sub‐cloud layer. A new scalar quantity related to the deficit of moist static energy detrained by the downdrafts mass flux is proposed. This quantity is subject to grid‐scale advection, mixing, and a sink term representing dissipation processes. The model is then applied to simulate moist convection development over a large portion of tropical land in the Amazon Basin in a wet and dry‐to‐wet 10‐days period. Our results show that the cold pool edge parameterization improves the organization, longevity, propagation, and severity of simulated MCS over the Amazon and other different continental areas.

Pollen analysis of honey and pollen stored by Melipona (Melikerria) fasciculata Smith, 1854 (Apidae Meliponini), in an Amazon and Cerrado transition area, Maranhão, Brazil.

The identification of meliponicultural flora is fundamental for the preservation of bees, as well as enabling the development of pollinator management and reforestation programs. In this context, this study aimed to investigate the types of pollen found in the honey and pollen pots of the Melipona fasciculata bee in Arari, State of Maranhão, between August 2022 and July 2023. 40 types of pollen were identified, distributed among 18 botanical families, with Fabaceae standing out (46.15% in pollen pots and 37.86% in honey pots), Myrtaceae (11.53% in pollen and 13.51% in honey) and Rubiaceae (7.69% in pollen and 5.40% in honey). Sapindaceae, in the honey pots, accounted for 5.40%. The other families showed lower percentages, 3.84% in the pollen pots and 2.70% in the honey pots. In terms of similarity, two distinct groups were observed in both the pollen and honey pots. In the pollen pots, group A (May-June ~ 97%) and group B (Feb-Mar ~ 99%) stood out, while in the honey pots, group A (Mar-Apr ~ 98%) and group B (Jun-Jul-Sept ~ 98%) showed the highest percentages. These findings highlight the wide range of resources used by the M. fasciculata species, as well asits preference for Fabaceae and Myrtaceae, due to the diversity and availability of trophic resources. An understanding of the meliponicultural flora is essential to support effective conservation strategies, which aim not only to guarantee the survival of the bees, but also to ensure the continued production of honey, a resource of great importance to local communities.

New genus of Steirodontini Brunner von Wattenwyl, 1878 (Orthoptera: Tettigoniidae: Phaneropterinae) from the Brazilian Amazon Rainforest.

The tribe Steirodontini (Phaneropterinae: Tettigoniidae) currently comprises five genera and 56 species, with its distribution restricted to the Neotropical region. In Brazil, four genera and 20 species of this tribe are recorded, all with records restricted to the Brazilian Southeast and South regions. This fact is a strong indication that the Brazilian fauna of this group is underestimated. In this work, the new monotypic genus Coronophyllum gen. nov. and the new species Coronophyllum catarinae sp. nov. from Amazonas, Brazil, are described and illustrated. Additionally, a map and comments on its distribution in an endemic area of the Brazilian Amazon are provided.

Spatial distribution of degradation and deforestation of palm swamp peatlands and associated carbon emissions in the Peruvian Amazon

The vast peat deposits in the Peruvian Amazon are crucial to the global climate. Palm swamp, the most extensive regional peatland ecosystem faces different threats, including deforestation and degradation due to felling of the dominant palm Mauritia flexuosa for fruit harvesting. While these activities convert this natural C sink into a source, the distribution of degradation and deforestation in this ecosystem and related C emissions remain unstudied. We used remote sensing data from Landsat, ALOS-PALSAR, and NASA's GEDI spaceborne LiDAR-derived products to map palm swamp degradation and deforestation within a 28 Mha area of the lowland Peruvian Amazon in 1990–2007 and 2007–2018. We combined this information with a regional peat map, C stock density data and peat emission factors to determine (1) peatland C stocks of peat-forming ecosystems (palm swamp, herbaceous swamp, pole forest), and (2) areas of palm swamp peatland degradation and deforestation and associated C emissions. In the 6.9 ± 0.1 Mha of predicted peat-forming ecosystems within the larger 28 Mha study area, 73% overlaid peat (5.1 ± 0.9 Mha) and stored 3.88 ± 0.12 Pg C. Degradation and deforestation in palm swamp peatlands totaled 535,423 ± 8,419 ha over 1990–2018, with a pronounced dominance for degradation (85%). The degradation rate increased 15% from 15,400 ha y−1 (1990–2007) to 17,650 ha y−1 (2007–2018) and the deforestation rate more than doubled from 1,900 ha y−1 to 4,200 ha y−1. Over 1990–2018, emissions from degradation amounted to 26.3 ± 3.5 Tg C and emissions from deforestation were 12.9 ± 0.5 Tg C. The 2007–2018 emission rate from both biomass and peat loss of 1.9 Tg C yr−1 is four times the average biomass loss rate due to gross deforestation in 2010–2019 reported for the hydromorphic Peruvian Amazon. The magnitude of emissions calls for the country to account for deforestation and degradation of peatlands in national reporting.

Functional leaf traits in congeneric species of tree communities in central Amazon

The Amazon is a Neotropical region that features various types of phytophysiognomies subject to multiple environmental filters. The Amazonian Savanna and Ombrophilous Forest areas support complex ecosystem functions and are sensitive to biotic and abiotic disturbances. The low availability of nutrients and water, along with the high solar exposure these vegetations experience, impose rigorous environmental filters that affect species distribution. Plant species with structural and functional adaptations can occur in specific locations due to environmental characteristics. We investigated potential variations in the functional leaf traits of congeneric species of Tachigali and Pouteria in different tree community vegetation types in savanna and forest areas in Central Amazon. For this purpose, using standard optical microscopy techniques and statistical models, we analyzed 9 congeneric species, with 3 individuals per species, of woody congeners from Ombrophilous Forest and Amazonian Savanna, both located in the state of Pará, Brazil. Fifteen anatomical traits, both quantitative and qualitative, possessing functional significance were evaluated by comparing tissues between forest and savanna plants, employing ANOVA and ordination analyses. The results indicate that variations in environmental conditions within different vegetation types might be linked to morphophysiological adjustments and strategies in leaves to resist environmental conditions. Species from the Amazonian Savanna present traits more related to conservative characteristics related to water retention and drought resistance, demonstrating a degree of leaf xeromorphism with greater thickness of leaves, palisade parenchyma and epidermal cells. On the other hand, forest species exhibited traits more related to acquisitive and diversified resource strategies, which may be characteristic of the greater availability of light, water and nutrients existing in this environment. The results show considerable variation in leaf traits among forested and savanna formations, and variations in leaf characteristics are expected to be essential for the survival and development of tree species within each type of vegetation.

Effects of Land Use on Soil Physical-Hydric Attributes in Two Watersheds in the Southern Amazon, Brazil

Changes in land use can cause degradation of soil physical quality with negative effects on the environment and agricultural production. The effects of different land uses on soil physical-hydric attributes were studied in the Renato River and Caiabi River watersheds in the southern Brazilian Amazon. Three conditions of land use were evaluated: native forest, crops, and pasture in the headwater, middle, and mouth of each watershed. Particle size, particle density, bulk density, total porosity, macroporosity, microporosity, water contents at field capacity and permanent wilting point, and available water capacity in soil were evaluated in three soil layers down to 0.4 m. Data collected were subjected to the Kruskal–Wallis nonparametric test and Pearson’s correlations. Multivariate analyses were also performed using the principal component method. In the Renato watershed, in comparison with native forest, conventional management of pasture and crops caused soil physical degradation, increasing soil density in the surface layer and reducing macroporosity and total porosity. In the Caiabi watershed, converting native forest areas into pasture and crops altered water quality, influencing the water dynamics in the soil, by reducing soil water conductivity. Soil attributes varied by watershed, with texture variations between the headwater and mouth, indicating that changes in soil properties result from both management and the granulometric composition of the soil in different regions of the same watershed. Adoption of crop and pasture conservation practices can improve soil physical attributes in regions bordering agricultural areas in the southern Amazon.

Bat flies (Diptera: Streblidae) of Phyllostominae and Stenodermatinae (Chiroptera: Phyllostomidae) bats from cocoa and natural areas of Amazonia

ABSTRACT Streblidae and Nycteribiidae are ectoparasitic flies exclusive to bats, with an estimated diversity of over 100 species in Brazil. Its distribution and abundance may be influenced by host’s shelter, geographic distribution, behavior, and size. Bat species respond differently to environmental changes, such as changing land use and land cover for cocoa production in the eastern Amazon. We sought to investigate the community of ectoparasite flies (Diptera: Streblidae) on Phyllostominae and Stenodermatinae (Chiroptera: Phyllostomidae) bats and the parasite-host interactions in cacao plantations and natural areas in the Brazilian Amazon. Twenty-two bats were collected, reaching a total of 54 flies. The observed richness was 15 (estimated in 24) species, with Trichobius dugesioides being the most abundant. The cacao plantations showed greater richness, eight species more than the natural ones, however, showing the absence of a specific distribution pattern for each area. This result may be because human interference in cocoa areas are barely perceptible, at least for the bats studied. In addition, the adoption of cabruca-type cocoa plantations can influence the result, as previously shown in the literature.

The Property Rights Index (PRIF) can be used worldwide to compare different forest governance systems

The bundle of forest landowners’ rights largely varies from one jurisdiction to another. On a global scale, the diversity of forest management regime and property rights systems is such that finding comprehensive and standardised approaches for governance analysis purposes is a challenging task. This paper explores the use of the Property Rights Index for Forestry (PRIF) as an analytical tool based on five rights domains (access, withdrawal, management, exclusion, and alienation) to assess how regulatory frameworks impact the owners’ forest property rights. We show that PRIF is a reliable index for various governance arrangements, considering its ability to score forest owners’ freedom to decide in case studies that range from the Amazon area (Brazil), Misiones province (Argentina) and Quebec (Canada) to community-managed Nepalese and Mexican forests. PRIF scores obtained in these diverse governance arrangements confirm that the governance of forests held by entities other than the state is driven by two factors: the owner’s ability to exclude the public from the use of his/her own resource and the owner’s freedom to decide on the forest management goals. These factors explained 66.44% of the variance in our sample and should be considered as the main potential drivers while implementing any new international or national policy. Despite having a few limitations, the PRIF is a promising governance indicator and has been proven to perform well for various socioeconomic and legal contexts.

Microplastic contamination in bathing areas in the Central Amazon, Itacoatiara, Brazil.

Due to the visible abundance of plastic improperly disposed of in the environment, the number of investigations has increased worldwide in different water bodies and biota. Despite this, studies of contamination by microplastics in freshwater environments in the Amazon are scarce. This study investigated microplastic contamination in sediment samples of bathing areas in the Central Amazon, in Itacoatiara, Amazonas, Brazil. A total of 202 microplastic particles were recorded in the five investigated areas that are used for recreation. These results indicate no significant difference in the number of microplastic particles among the establishments; however, the size of the microplastic particles differed significantly between the establishments. Both blue and red microplastic particles were recorded, with blue particles being the most abundant. The microplastic particles were in the form of fibers and fragments. The number of microplastic particles was significantly different between the areas within and adjacent to the bathing areas, though the size of the microplastic particles was not significantly different in the areas within and adjacent to the bathing areas. There was no significant correlation in the establishments in regard to their frequency of use and contamination (number of microplastic particles). This is the first study that indicates the anthropogenic impacts associated with microplastic contamination in recreation areas within the Amazon Forest, an area considered by the world to be of vital importance for conservation. The results of this study indicate that microplastics are present in these bathing areas of the Central Amazon and that contamination in areas used for recreation may be significantly higher than in areas not used for this purpose.

Describing the Urban Jungle: A Multicriteria Urbanization Index for the Amazon

The Amazon has a population that is largely urban. However, research is limited regarding representations and analysis of the urban Amazon. This article represents and describes Amazonian urban areas by applying a multicriteria urbanization index. Using the Ecuadorian Amazon as a case study, we constructed this index considering spatial indicators of fractal dimension, number of paved streets, urban luminosity, population density, and Euclidean distances from each urban patch to the closest deforested area, to the closest oil pollution point, and to the closest mining pollution point. The multicriteria urbanization index was classified in five classes (degrees) of urbanization: very low, low, medium, high, and very high levels of urbanization. Most of the urban areas have a low degree of urbanization; notwithstanding, there are areas with a medium degree of urbanization encompassing consolidated cities and suburbs, with a high potential for extension in the future. There are also areas of high and very high urbanization related to the oil industry, including cities which have a high impact on the territorial system of the Amazon. This investigation serves as an introduction to multidimensional spatial and quantitative analyses of the urban Amazon. We suggest monitoring the urban advance in the Amazon using the index developed in this investigation, to support better territorial planning in this region of the world having high strategical importance.