Northwest Amazon Research Articles

Spatially Compounding Drought Events in Brazil

AbstractSpatially compounding drought events affect multiple locations simultaneously, severely affecting food, water, energy, human health, and infrastructure sectors. Despite the cascading impacts and challenges compound droughts impose on society, we still lack an in‐depth understanding of spatially connected drought occurrences. Given the complexity and costs of droughts in Brazil, identifying regions prone to co‐experiencing droughts is critical for developing effective adaptation measures. Here, we develop a novel framework to assess the spatial co‐occurrence of hydrological drought events, which can be adapted for global applications to evaluate spatially compounding drought. This framework involves extracting drought data from individual catchments and calculating the co‐occurrence of droughts across all catchments. We apply this method to investigate the spatial connectedness of droughts in 511 Brazilian catchments over 39 years (1983–2022). Additionally, we classify catchments based on drought duration, intensity, deficit, number of events, and spatial connectedness to identify regions with similar drought behavior. Our findings reveal significant variability in drought characteristics and connectedness across Brazil, with the Central‐Northeast and Northwest Amazon regions being most affected by multiple and widespread droughts. We identify five distinct regions in Brazil that exhibit common drought behaviors, sharing attributes such as aridity, catchment area, and precipitation seasonality. These regions hold the potential to guide future adaptation plans for managing hydrological compound extremes at both the catchment and regional scales, including the development of risk pool networks. Our results underscore the importance of considering the interactions of spatially compounding hydrological droughts in risk assessments and adaptation strategies.

Association between detection rate of norovirus GII and climatic factors in the Northwest Amazon region

Worldwide, approximately one fifth of all cases of diarrhea are associated with norovirus, mainly in children, with a defined seasonality in temperate climates, but seasonal dynamics are less known in tropical climates. The objective was to investigate the impact of external clinical, epidemiological, and climatic factors on norovirus detection rates in samples from children under 5 years of age from Roraima, the Amazon region of Brazil. A total of 941 samples were included. According to climatic factors, we observed correlations between external climatic factors and weekly positivity rates, where temperature (P = 0.002), relative humidity (P = 0.0005), absolute humidity (P < 0.0001) and wind speed had the strongest effect (P = 0.0006). The Brazilian Amazon region presents a typical and favorable scenario for the persistence, expansion, and distribution of viral gastroenteritis. ImportanceThis study is important as it will serve as a basis for studies carried out in Brazil and Latin American countries on the epidemiological importance, seasonality, climate change, antigenic diversity, among other factors in the circulation of gastroenteric virus.

Vegetation response to Holocene hydroclimatic variability in the aseasonal forests of the north-western Amazon

Projected warming and intensification of the hydrological cycle across the Amazon threatens the functioning of some of the most biodiverse ecosystems on the planet. Interfluvial wetlands, or wetlands fed directly by precipitation or small streams, may be some of the most vulnerable to future hydroclimatic changes. In this study, we investigated a 7300-year-old sedimentary archive from an upland palm swamp in the Yasuní National Park (Ecuador) to reconstruct past vegetation dynamics, palaeo-hydroclimatic conditions and human history using pollen, charcoal and geochemical analysis. Pollen data revealed: i) a forest composition influenced by dry conditions 6000 years ago, ii) the development of a palm swamp 4500 years ago, and iii) the establishment of the modern closed-canopy Mauritia flexuosa dominated swamp (moretal) 400 years ago. X-ray fluorescence data indicated that changes in vegetation composition were related to fluctuations in relative moisture levels, which occurred coeval to identified regional climatic events, particularly the Mid Holocene Dry Event (MHDE). Analysis of charcoal revealed continuous presence of fire, albeit at very low levels, since 5000 cal yr BP, with increased values during the last millennium. Our results suggest a footprint of hydroclimatic transitions in the mid-to-late Holocene in the aseasonal forests of the northwest Amazon, highlighting the need to better understand the long-term ecology of these systems to better protect them in light of future climatic change.

Women, manioc and artefacts: body, gender and socialities in Northwest Amazonia

Resumo Neste artigo, argumentamos que as relações entre mulheres tukano orientais, manivas/mandiocas e artefatos de roça/casa-cozinha são orientadas por uma ética do cuidado que está pautada na composição vegetal e artefatual do corpo da mulher, o que implica uma relação de mútua afetação. Ao desenredar aspectos conceituais e práticos em torno de definições do ser mulher e de corporalidades femininas, demonstramos que a atribuição xamânica do nome no nascimento e sua complexificação na menarca, que envolve a ‘encorporação’ na mulher, de sementes e estacas de manivas e artefatos de roça/casa-cozinha, compõem corpos-pensamentos direcionados para o cultivo e o processamento de mandiocas, habilidades que só são desenvolvidas plenamente quando há por parte da menina/moça o interesse no aprendizado experimental junto a mulheres mais velhas nas roças e casas-cozinhas. A transformação da moça em uma mulher tukano oriental, que é dona de roça e dona de casa-cozinha, envolve o domínio e a manipulação de uma coleção composta por variedades de manivas e de artefatos. Concepções, práticas e relações se alteram em um complexo jogo que envolve composição familiar, biografia e transformações sociais.

Temporalities and socio-environmental interactions in the Northwest Amazon: introduction to the dossier

Temporalities and socio-environmental interactions in the Northwest Amazon: introduction to the dossier

The spirit with no anus and the pots that fart: ceramics of life and death in Northwest Amazonia

The spirit with no anus and the pots that fart: ceramics of life and death in Northwest Amazonia

G6P[8] Rotavirus a Possessing a Wa-like VP3 Gene from a Child with Acute Gastroenteritis Living in the Northwest Amazon Region.

The introduction of rotavirus A (RVA) vaccines has considerably reduced the RVA-associated mortality among children under 5 years of age worldwide. The ability of RVA to reassort gives rise to different combinations of surface proteins G (glycoprotein, VP7) and P (protease sensitive, VP4) RVA types infecting children. During the epidemiological surveillance of RVA in the Northwest Amazon region, an unusual rotavirus genotype G6P[8] was detected in feces of a 2-year-old child with acute gastroenteritis (AGE) that had been vaccinated with one dose of Rotarix® (RV1). The G6P[8] sample had a DS-1-like constellation with a Wa-like VP3 gene mono-reassortment similar to equine-like G3P[8] that has been frequently detected in Brazil previously. The results presented here reinforce the evolutionary dynamics of RVA and the importance of constant molecular surveillance.

One size (doesn't) fit all: new metaphors for and practices of scaling from indigenous peoples of the Northwest Amazon.

Ten years of field research and collaborative development of programs for early childhood in the Upper Rio Negro region of the Amazon provide the authors with new metaphors for achieving wider social impact and new frames to add to the international debate on 'scaling' social change initiatives. Using anthropology and ethno-ontology to think questions of universal and particular, center and periphery, the article reflects on the dangers of monolithic scaling to cultural diversity and future innovation. Instead of the metaphor of scaling - adopted in the discourse of public policy and international development from the Fordist or Taylorist efficiency of the economy of scale - indigenous people speak of exchange, sharing, and transformation. These ideas seek to connect local and decolonized models and value the diversity of local knowledges, epistemologies, and practices around early childhood development. Based on the expansion of the CanalCanoa project among diverse indigenous communities, the paper proposes a flexible and bottom-up model of achieving impact at scale through empowering local actors to teach each other and establish local criteria of learning and evaluation.

Lexically driven patterns of contact in alignment systems of languages of the northern Upper Amazon

AbstractDespite ample attention in the literature for alignment patterns and case frames more generally, we know very little about how these elements of grammar spread from one language to another in a contact situation. Achieving a better understanding of this will help explain areal patterns in alignment and grammatical relation marking. In this contribution, we zoom in on a contact situation in the foothills of North-West Amazon, where languages of the Quechuan and Tukanoan families are in contact, and where previous authors have suggested that grammatical relation marking shows many potential contact effects. We find that, despite the absence of loanwords, abstract lexico-grammatical information associated with individual lexical items may spread from one language to another, especially within the class of sensation predicates. These can be characterized as lexically driven diffusion patterns, without formal borrowing, consistent with an overall characterization of the area’s sociolinguistics as loanword-avoiding.

Narratives on menstruation and its transformations in the Northwest Amazon

Resumo: Neste artigo, coloco em primeiro plano narrativas femininas Tukano, Desana e Tuyuka, sobre as transformações dos cuidados na primeira menstruação, e demonstro como estas mulheres formulam as variações nas práticas de (auto)cuidado em termos de moralidades elaboradas na forma de regras/leis [duhtiro] atreladas a diferentes espacialidades-temporalidades; tempo das avós e das malocas, tempo dos padres e freiras e internatos, tempo dos pais e das comunidades e escolas indígenas; que podem coexistir de acordo com a configuração de cada família e as experiências pessoais. As memórias possuem teor afetivo e moral e revelam vulnerabilidades, responsabilidades e cuidados realizados para proteção de si e dos outros, que conformam diferenças geracionais e de gênero e orbitam ao redor do universo conceitual das encantações xamânicas [bahsese], aconselhamentos [werese], e abstinências [betise].

The social lives of isolates (and small language families): the case of the Northwest Amazon.

The Americas are home to patches of extraordinary linguistic (genealogical) diversity. These high-diversity areas are particularly unexpected given the recent population of the Americas. In this paper, we zoom in on one such area, the Northwest Amazon, and address the question of how the diversity in this area has persisted to the present. We contrast two hypotheses that claim opposite mechanisms for the maintenance of diversity: the isolation hypothesis suggests that isolation facilitates the preservation of diversity, while the integration hypothesis proposes that conscious identity preservation in combination with contact drives diversity maintenance. We test predictions for both hypotheses across four disciplines: biogeography, cultural anthropology, population genetics and linguistics. Our results show signs of both isolation and integration, but they mainly suggest considerable diversity in how groups of speakers have interacted with their surroundings.

Amazonian Forest Peoples' Perceptions of Malaria on the Upper Rio Negro, Brazil, are Shaped by Both Local and Scientific Knowledge

Malaria is endemic in Brazilian Amazonia, accounting for 99% of national cases. Amazonian forest peoples (both Indigenous and traditional) understand and treat the disease based on their knowledge, rituals, and religion. In recent decades, biomedical health coverage has expanded in the region, with implications for local perceptions and practices to prevent, treat, and recover from malaria. This paper attempts to understand how the expansion of biomedical healthcare among forest peoples interacts with their ethnomedicinal knowledge. Our results clearly indicate that most of our research participants in rural northwest Amazonia believe that malaria has a variety of causes, forms of prevention, and treatment. We also found that these beliefs are shaped by both local knowledge (including Indigenous) and some technical concepts of biomedicine. Consequently, new approaches and practices in healthcare need to be developed which consider forest peoples' perceptions and understanding.

‘Sparks of Kuwai’

The spread of Covid-19 among the vulnerable indigenous populations of Amazonia has produced complex moral and spiritual issues that have demanded creative and cooperative solutions. The Baniwa indigenous peoples of the Northwest Amazon pin the spread of the pandemic on the failure of humans to observe respectful relations with the spirit-people of the environment. Ritual specialists typically believe that the pandemic is due to humans having violated the original instructions, remembered in initiation ceremonies and reinforced throughout a lifetime. Consequently, they further believe, the spirit-people of the environment retaliate by inflicting sicknesses, including the Covid-19 pandemic. To reverse the damage, a strong movement of healthcare led by indigenous women has promoted a revitalization of the use of herbal medicines together with healing practices and the traditional teachings of the initiation rites for men and women.

Situating in Place Indigenous Engagements in Capitalist Market Relations

We use a decolonial approach to political economy and a social conceptualization of space to examine how Indigenous cultural understandings and knowledge mediate market rationalities in context. Indigenous Awajún notions of tajimat pujut (life in abundance) and their horticulturalist practices are embedded in a relational ontology that situates humans as part of the ecosystem in the Peruvian Northwest Amazon. As the Awajún are increasingly incorporated into market economies, these notions and practices interact and, at times, converge with the instrumental rationalities of neoliberalism and notions of sustainability and equity that are embedded in local agricultural support programs. We detail these interactions by drawing on ethnography and secondary sources. In the case of the Awajún, we find that Indigenous rationalities are not entirely subsumed by neoliberalization. To the contrary, Awajún values of tajimat pujut and their relationship with the Amazonian territory mediate, transform, and delimit neoliberal governmentality practices. These discourses and relations coexist in tension with an emerging marketization of the Amazon, and are being reworked through contradictions that shape Indigenous productive decisions and impact the sustainability of the forest. Marketization creates opportunities for the native population to obtain income while promoting capital circulation in neighboring markets and amplifying nascent inequalities. Tajimat pujut resonates with discourses and policies relating to pro-poor sustainable local development, producing an Awajún preference for small crop production and aversion to forest depletion, contrary to mestizo preferences for intense monoculture. In this way, neoliberalization is rendered incomplete even as market relations are increasingly incorporated into Awajún economic practices.

Insecurity through diversity: a case study from the Northwest Amazon

ABSTRACT This paper uses the themes of language rights, language choice, and language risk to consider linguistic insecurity in the Northwest Amazon (Upper Negro river) region of Brazil. Because the region is home to a large number of languages (c. two dozen), the idea of preserving this diversity is a popular theme in discourses about language in the Upper Negro river. I argue that the ideologies underlying the goal of preserving ‘diversity’ as a concept are not, in fact, the same ones that have sustained the presence of these languages thus far, especially as concerns the Tukanoan languages of the Uaupés basin (Jackson, J. E. 1983. The Fish People: Linguistic Exogamy and Tukanoan Identity in Northwest Amazonia. Cambridge, UK: Cambridge University Press). Paradoxically, the reification of ‘diversity’ as a characteristic of the Northwest Amazonian Indigenous population has tended to promote homogenisation among groups that have historically valued differentiation from one another. In examining ideologies and practices surrounding each of the three themes of this issue, I suggest that discourses of ‘diversity’, applied at the local level, can create complex outcomes for the languages they are used to promote.

Situating in Place Indigenous Engagements in Capitalist Market Relations

We use a decolonial approach to political economy and a social conceptualization of space to examine how Indigenous cultural understandings and knowledge mediate market rationalities in context. Indigenous Awajún notions of tajimat pujut (“life in abundance”) and their horticulturalist practices are embedded in a relational ontology that situates humans as part of the ecosystem in the Peruvian Northwest Amazon. As the Awajún are increasingly incorporated into market economies, these notions and practices interact and, at times, converge with the instrumental rationalities of neoliberalism and notions of sustainability and equity that are embedded in local agricultural support programs. We detail these interactions by drawing on ethnography and secondary sources. In the case of the Awajún, we find that Indigenous rationalities are not entirely subsumed by neoliberalization. To the contrary, Awajún values of tajimat pujut and their relationship with the Amazonian territory mediate, transform, and delimit neoliberal governmentality practices. These discourses and relations coexist in tension with an emerging marketization of the Amazon, and are being reworked through contradictions that shape Indigenous productive decisions and impact the sustainability of the forest. Marketization creates opportunities for the native population to obtain income while promoting capital circulation in neighboring markets and amplifying nascent inequalities. Tajimat pujut resonates with discourses and policies relating to pro-poor sustainable local development, producing an Awajún preference for small crop production and aversion to forest depletion, contrary to mestizo preferences for intense monoculture. In this way, neoliberalization is rendered incomplete even as market relations are increasingly incorporated into Awajún economic practices.

Ancient Human Genomes and Environmental DNA from the Cement Attaching 2,000-Year-Old Head Lice Nits.

Over the past few decades, there has been a growing demand for genome analysis of ancient human remains. Destructive sampling is increasingly difficult to obtain for ethical reasons, and standard methods of breaking the skull to access the petrous bone or sampling remaining teeth are often forbidden for curatorial reasons. However, most ancient humans carried head lice and their eggs abound in historical hair specimens. Here we show that host DNA is protected by the cement that glues head lice nits to the hair of ancient Argentinian mummies, 1,500–2,000 years old. The genetic affinities deciphered from genome-wide analyses of this DNA inform that this population migrated from north-west Amazonia to the Andes of central-west Argentina; a result confirmed using the mitochondria of the host lice. The cement preserves ancient environmental DNA of the skin, including the earliest recorded case of Merkel cell polyomavirus. We found that the percentage of human DNA obtained from nit cement equals human DNA obtained from the tooth, yield 2-fold compared with a petrous bone, and 4-fold to a bloodmeal of adult lice a millennium younger. In metric studies of sheaths, the length of the cement negatively correlates with the age of the specimens, whereas hair linear distance between nit and scalp informs about the environmental conditions at the time before death. Ectoparasitic lice sheaths can offer an alternative, nondestructive source of high-quality ancient DNA from a variety of host taxa where bones and teeth are not available and reveal complementary details of their history.

Number Marking in Nadëb

&#x0D; &#x0D; &#x0D; One of the most robust sources of fresh insights into typological categories comes from our growing knowledge of the indigenous languages of South America, a region that until recently has been significantly under-represented in typological studies. This paper offers a case in point through the investigation of number in Nadëb, a member of the small Naduhup family of the northwest Amazon, which reveals several typologically intriguing features. One of these is Nadëb’s emphasis on marking number on the verb as opposed to the noun, even while any registering of event number appears to be secondary to that of participant number. Nadëb also relies heavily on suppletive or semi-suppletive stem pairs in encoding numberdistinctions in both nouns and verbs. Finally, Nadëb’s resources for expressing number are quite different from those seen in its three sister languages, in which number is primarily a feature of the noun phrase, suggesting a significant reorganization of number-marking within the language family. The Nadëb case underscores the considerable diversity evident in number-marking strategies typologically, and how this diversity may emerge even within a single language family of limited time-depth.&#x0D; &#x0D; &#x0D;

Croton lechleri Extracts as Green Corrosion Inhibitors of Admiralty Brass in Hydrochloric Acid.

Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy techniques. Chloroform alkaloid-rich extracts resulted in IE% of 57% at 50 ppm, attributed to the formation of a layer of organic compounds on the AB surface that hindered the dezincification process. The formulation of corrosion inhibitors from C. lechleri latex allows for the valorization of non-edible natural sources and the diversification of the offer of green corrosion inhibitors for the chemical treatment of heat exchangers.

Multilingual Networks Past and Present: Insights from Naduhup Languages of Northwest Amazonia

Abstract: In Amazonia, interfluvial groups such as the Naduhup (Makú) peoples of the northwest Amazon have tended to be less visible than riverine peoples in the historical record, but are also more likely to maintain their cultural and linguistic identity over time. Hence the languages of these groups may offer insights into Indigenous histories that have otherwise been largely overlooked or obliterated. Lexicon, grammar, and discourse indicate that the Naduhup peoples have long been deeply integrated within multilingual, interactive regional networks—some still extant, but others long obscured by their disruption centuries ago through the colonial onslaught.