Background Open defecation (OD) is recognised as an important public health challenge in low-income and middle-income countries. Although agriculture is the main occupation in these countries, few if any study on OD has focused on agricultural households. In order to enhance the prevention of OD and contribute to a better understanding of this health-threatening behaviour, this paper analyses the socio-economic factors associated with OD practice among agricultural households in Haiti. Methods The study used primary data from 1269 households selected in 5 out of 10 geographic departments of Haiti surveyed in 2020–2021. Descriptive statistics and bivariate analysis were used to identify households’ characteristics that were significantly associated with OD. In addition, a multivariate analysis was performed using binary logistic regression to study the factors associated with the probability to defecate in the open. Results Findings show that one out of five (20.1%) agricultural households in Haiti practices OD. More than 26% of the households did not have any member with secondary school education level. Multivariate analysis revealed that in addition to the location, the probability of OD practices among agricultural households was correlated with socio-economic factors such as education, access to the media, plot number and livestock, level of specialisation in the agriculture, agricultural income and participation in local organisations. Conclusion While Haiti is struggling with cholera among other health issues, this paper sheds light on factors associated with OD, a health-threatening and unsustainable sanitation behaviour. According to the results, in addition to toilet acquisition subsidies, awareness campaigns need to make use of mass media and local organisations particularly women and community ones. Elimination of OD among agricultural households is of great significance for better quality of foods and vegetables at watershed level.
Changes in marine productivity of the last five centuries in the Gulf of Tehuantepec were investigated using a high-resolution record of diatoms, organic carbon (C org ), total nitrogen (TN), Ni/Al, and Cu/Al. The laminated sediments were dated by using ²¹⁰ Pb and ¹⁴ C, with a bayesian age model providing a new Δ R = 247 ± 30 years for the bulk sediment. The Little Ice Age (LIA) (~1500 to ~1858 CE) was characterized by the predominance of cold-water and high productivity diatoms ( Chaetoceros spores, Thalassionema nitzschioides, Lioloma pacificum, Thalassiosira nanolineata, and Rhizossolenia setigera) and high values of geochemical productivity proxies. A transition period (~1860 to ~1919 CE) toward warmer conditions related to the end of the LIA and the beginning of the Current Warm Period (CWP), was indicated by the appearance of warm-water diatoms ( Neodelphineis pelagica, Thalassiosira tenera, and Rhizossolenia bergonii), as well as lower values of C org , TN, Ni/Al, and Cu/Al. The most recent period of the CWP (~1920 CE to today) was characterized by the increased abundance warm-water taxa ( N. pelagica, Cymatodiscus planetophorus, T. tenera, Plagiogramma minus, Nitzschia interruptestriata, and R. bergonii), and by the prevalence of low values of C org , TN, Ni/Al, and Cu/Al. These changes in productivity during the LIA and CWP were likely driven by changes in solar irradiance and the migration of the Intertropical Convergence Zone. This study highlights the spatial extent of the LIA in the Eastern Tropical North Pacific and contributes to the knowledge of the productivity response to climate in tropical regions.
COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91,056 participants from 154 countries participated in this cross-sectional study. Information on the use of sanitizers and disinfectants and health was collected using an electronic questionnaire, which was translated into 26 languages via web-based platforms. The findings of this study suggest that detergents, alcohol-based substances, and chlorinated compounds emerged as the most prevalent chemical agents compared to other sanitizers and disinfectants examined. Most frequently reported health issues include skin effects and respiratory effects. The Chi-square test showed a significant association between chlorinated compounds (sodium hypochlorite and per-chlorine) with all possible health effects under investigation (p-value <0.001). Examination of risk factors based on multivariate logistic regression analysis showed that alcohols and alcohols-based materials were associated with skin effects (OR, 1.98; 95%CI, 1.87–2.09), per-chlorine was associated with eye effects (OR, 1.83; 95%CI, 1.74–1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90–2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92–2.44). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92–2.44). The use of sodium hypochlorite and per-chlorine also had a high chance of having respiratory effects. The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics especially when they are used or overused.
This study aims to reconstruct the hydro-climatic variations over the last 1000years in Haiti using mineralogical and geochemical composition of well dated lacustrine sediment core retrieved from Lake Azuei. The results show changes in sedimentological processes linked to environmental and climatic variations. The general pattern suggests a wetter Medieval Climate Anomaly (MCA), drier Little Ice Age (LIA), high climate variability during the MCA-LIA transition and more anthropogenic impacts that dominate natural climate during the Current Warm Period (CWP). The MCA period (~1000–1100 CE) thus appears marked by increase sedimentation rate supported by higher terrigenous input linked to erosive events particularly increases in precipitation. During the LIA, particularly from ~1450 to 1600 CE, there is a great variation toward a decrease of terrigenous input, which is related to a decrease on sedimentation rate and increase Mg-calcite precipitation, suggesting less precipitation and high evaporation respectively during dry climate conditions. The MCA-LIA transition (~1200–1400 CE) is characterized by variations between terrigenous input, Mg-calcite formation and organic matter deposition, which indicate succession of dry and humid conditions. The CWP (1800–2000CE) shows a progressive increase on sedimentation rate and decrease of gray level, which indicate more organic matter sedimentation as consequence of anthropogenic activities in the surrounding basin of the lake. High- resolution gray level analysis, which reflects principally variations in terrigenous input, carbonate mineral formation and organic matter deposition, shows that the AMO, NAO, PDO and ENSO are the principal modes affecting the hydro-climatic changes in Haiti during the last millennium. In addition, temporal correlation of other Caribbean paleoclimate records with our geochemical and mineralogical data, suggests that trends observed in Lake Azuei were controlled by regional climate, likely associated with shifts in the position of the ITCZ.
Background Young women in Haiti remain vulnerable to sexually transmitted infections and unintended pregnancy. However, little is known about condom use among this population. This study examined the prevalence and the factors associated with condom use among sexually active young women in Haiti. Methods Data from the 2016/17 Haiti demographic and health survey were used. The prevalence and the factors associated with condom use among sexually active young women in Haiti were assessed using descriptive statistics and binary logistic regression model. Results The prevalence of condom use was 15.4% (95% CI 14.0–16.8). Being teenage (AOR = 1.34; 95% CI: 1.04–1.74), living in urban areas (AOR = 1.41; 95% CI = 1.04–1.90), having higher education level (AOR = 2.39; 95% CI: 1.44–4.00), being in the middle or rich category of household wealth index (AOR = 2.32; 95% CI: 1.53–3.53 and AOR = 2.93; 95% CI: 1.90–4.52), having correct knowledge of ovulatory cycle (AOR = 1.65; 95% CI: 1.30–2.10), having 2–3 lifetime sexual partners and one lifetime sexual partner (AOR = 2.04; 95% CI: 1.36–3.06 and AOR = 2.07; 95% CI: 1.35–3.17) had significantly higher odds of using condom. In addition, sexually active young women whose last partner was their boyfriend (AOR = 4.38; 95% CI: 2.82–6.81), and those whose last partner was a friend/casual acquaintance/commercial sex worker (AOR = 5.29; 95% CI: 2.18–12.85) were associated with increased likelihood of using condom compared with their counterparts whose partner was their spouse. Conclusion The Haitian government as well as institutions involved in sexual health should consider these factors when designing sexual and reproductive health interventions targeting young women. More specifically, to increase condom use and reduce risky sexual behaviors, they should combine efforts to raise awareness and induce sexual behavioral changes at two levels. In the education system, they should reinforce sexual education in primary and secondary schools while paying special attention to rural areas. In the whole society, it is important to deepen efforts toward increased awareness on family planning and condom use, through mass media and local organizations including religious ones. Priority should be given to the poorer households, young people and women, and rural areas, in order to maximize reduction in early and unintended pregnancy, and sexually transmitted infections. Interventions should include a condom price subsidy and a campaign to destigmatize condom use which is actually a “male affair”.
Sustainably addressing the water needs of populations in countries lacking adequate infrastructure is challenging. We discuss the potential of decentralized water and wastewater treatment using electrified processes across Latin American countries and reflect on what would help their implementation in the region.
Background: Open defecation (OD) remains an important public health challenge in Haiti. The practice poses a significantly high risk of disease transmission. Considering these negative health consequences, this paper aims to identify socio-economic and demographic factors that influence OD practice among households in Haiti. Methods: The study used secondary data from 13,405 households from the Haiti Demographic and Health Survey 2016-2017. Descriptive statistics and bivariate analysis were used to find the preliminary results. Further, multivariate analysis was performed to confirm the findings. Results: Around one quarter (25.3%) of Haitian households still defecate in the open, almost 10% in urban areas, and nearly 36% in rural areas. Multivariate analysis revealed that the age and sex of the household head, household size, number of children aged 1-14 years old in the household, education level, wealth index, access to mass media, place of residence, and region were significant predictors of OD practice among households in Haiti. Conclusion: To accelerate the elimination of OD by 2030 and therefore achieve sustainable open defecation-free status, the government of Haiti and its partners should consider wealth disparities among regions and mobilize mass media and community-based networks to raise awareness and promote education about sane sanitation practices. Furthermore, because the possibilities to build toilets differ between rural and urban areas, specific interventions must be spearheaded for each of these regions. The public program can subsidize individual toilets in rural areas with room to collect dry excreta for the preparation of fertilizers, while in urban areas collective toilets can be built in slums. Interventions should also prioritize households headed by women and young people, two underpriviledged socioeconomic groups in Haiti.
COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91056 participants from 154 countries participated in this cross-sectional study through an electronic questionnaire. Results implied that detergents (67%), alcohol-based materials (56%), and chlorinated compounds (32%) were the most commonly used types of sanitizers and disinfectants. Most frequently reported health issues include skin complications 48.8% and respiratory complications 29.8%. The Chi-square test showed a significant association between chlorinated compounds with all possible health complications under investigation (p-value < 0.001). Examination of risk factors based on multivariate regression analysis showed that alcohols-based materials were associated with skin complications (OR, 1.98; 95%CI, 1.87–2.09), per-chlorine was associated with eye complications (OR, 1.83; 95%CI, 1.74–1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90–2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological complications (OR, 2.17; 95%CI, 1.92–2.44). The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics.
The creation of global research partnerships is critical to produce shared knowledge for the implementation of the UN 2030 Agenda for Sustainable Development. Sustainability science promotes the coproduction of inter- and transdisciplinary knowledge, with the expectation that studies will be carried out through groups and truly collaborative networks. As a consequence, sustainability research, in particular that published in high impact journals, should lead the way in terms of ethical partnership in scientific collaboration. Here, we examined this issue through a quantitative analysis of the articles published in Nature Sustainability (300 papers by 2135 authors) and Nature (2994 papers by 46,817 authors) from January 2018 to February 2021. Focusing on these journals allowed us to test whether research published under the banner of sustainability science favoured a more equitable involvement of authors from countries belonging to different income categories, by using the journal Nature as a control. While the findings provide evidence of still insufficient involvement of Low-and-Low-Middle-Income-Countries (LLMICs) in Nature Sustainability publications, they also point to promising improvements in the involvement of such authors. Proportionally, there were 4.6 times more authors from LLMICs in Nature Sustainability than in Nature articles, and 68.8–100% of local Global South studies were conducted with host country scientists (reflecting the discouragement of parachute research practices), with local scientists participating in key research steps. We therefore provide evidence of the promising, yet still insufficient, involvement of low-income countries in top sustainability science publications and discuss ongoing initiatives to improve this.
Introduction: Cardiovascular disease is the leading cause of death in Haiti and many low-middle income countries. Environmental lead exposure is associated with higher blood pressure (BP) and cardiovascular disease mortality in high income countries but has not been systematically evaluated in lower income countries where 6.5 billion people reside. Hypothesis: We hypothesized higher lead levels would be associated with higher BP in Haiti. Methods: Blood lead levels (BLLs) were measured among 2,257 participants ≥18 years enrolled in a population-based longitudinal cohort study in Port-au-Prince (Haiti Cardiovascular Disease Cohort Study). BLL screening was conducted using LeadCare II (detection limit ≥3.3 μg/dL). BLLs below detection were imputed. Associations between BLLs (quartiles) and systolic BP (SBP) and diastolic BP (DBP) were assessed, adjusting for age, sex, obesity, smoking, physical activity, and income. BLLs were also categorized as ≥5 versus <5 μg/dL. Results: The median age was 40 years; 62.6% were female. The geometric mean BLL was 4.60 μg/dL, 67.3% had detectable BLLs >3.3 μg/dL, and 40.9% had elevated BLLs ≥5 μg/dL. BLLs in quartile four (≥6.5 μg/dL) in both unadjusted and adjusted analyses were associated with higher SBP (adjusted 3.02 mmHg; 95%CI 0.80, 5.25) and DBP (adjusted 2.19 mmHg; 95%CI 0.70, 3.67). BLL ≥5 μg/dL were associated with a higher SBP (2.21 mmHg; 95%CI 0.15, 4.26) and DBP (1.50 mmHg; 95%CI 0.20, 2.81) in unadjusted analysis. After adjustment there was no difference in SBP (1.41; 95%CI -0.25, 3.09) and 1.15 mmHg (95%CI 0.01, 2.30) higher DBP. Conclusions: Widespread environmental lead exposure is evident in urban Haiti, with higher BLLs associated with higher SBP and DBP. Lead is a modifiable pollutant in low-income countries that warrants urgent public health remediation.
Background: Haiti is one of the Caribbean countries where malaria persists. More than 99% of malaria cases are caused by Plasmodium falciparum, the main vector being the mosquito Anopheles albimanus. In this paper, we describe the epidemiological profile of malaria in Haiti between 2009 and 2018. Methods: We analyzed information on cases reported by the Ministry of Health of Haiti and the World Health Organization (WHO). Results: Between 2009 and 2018, 232,479 malaria cases were reported by the Ministry of Public Health and Population (MSPP); an increase in the incidence of malaria in the country in 2010, followed by a decrease in 2011, was primarily observed. Due to recent efforts to reduce malaria by 2020, its incidence declined from 60,130 cases in 2010 to 8,978 cases in 2018. Controversially, in terms of the number of reported cases, the MSPP and WHO report conflicting data. However, the results from both datasets present the same trend in Haiti from 2009 to 2018. The results also illustrate the endemicity of the disease throughout Haiti, both in rural and urban areas, especially along the coast. Conclusions: This study emphasizes the need to promote official data collection and analyses, as well as the application of epidemiological surveillance of malaria at the municipal level, for a better understanding of the real impact of malaria on the Haitian population and to create more appropriate interventions.
Rapid environmental change can lead to population extinction or evolutionary rescue. The global staple crop sorghum (Sorghum bicolor) has recently been threatened by a global outbreak of an aggressive new biotype of sugarcane aphid (SCA; Melanaphis sacchari). We characterized genomic signatures of adaptation in a Haitian breeding population that had rapidly adapted to SCA infestation, conducting evolutionary population genomics analyses on 296 Haitian lines versus 767 global accessions. Genome scans and geographic analyses suggest that SCA adaptation has been conferred by a globally rare East African allele of RMES1, which spread to breeding programs in Africa, Asia, and the Americas. De novo genome sequencing revealed potential causative variants at RMES1. Markers developed from the RMES1 sweep predicted resistance in eight independent commercial and public breeding programs. These findings demonstrate the value of evolutionary genomics to develop adaptive trait technology and highlight the benefits of global germplasm exchange to facilitate evolutionary rescue.
We consider a stochastic financial exchange economy with a finite date-event tree representing time and uncertainty and a financial structure with possibly long-term assets. We address the question of the continuity of the set of marketable payoffs with respect to the asset prices. In a previous paper, we have exhibited a sufficient condition, which is based only on the returns of the assets. However, it is never satisfied in the structures with re-trading [See Bonnisseau and Chéry (Ann Finance 10:523–552, 2014)], which is a very common feature in many papers following the model of Magill and Quinzii (Theory of Incomplete Markets, MIT Press, Cambridge, 1996). The main purpose of this paper is to address this issue. We exhibit a new sufficient condition for general financial structures, which enjoys the property to be inherited by the re-trading extension of a financial structure. So, we pave the way for equilibrium existence results under assumptions only on the fundamentals of the economy.
Cardiovascular disease is the leading cause of death in lower-income countries including Haiti. Environmental lead exposure is associated with high blood pressure and cardiovascular mortality in high-income countries but has not been systematically measured and evaluated as a potential modifiable cardiovascular risk factor in lower-income countries where 6.5 billion people reside. We hypothesized lead exposure is high in urban Haiti and associated with higher blood pressure levels. Blood lead levels were measured in 2504 participants ≥18 years enrolled in a longitudinal population-based cohort study in Port-au-Prince. Lead screening was conducted using LeadCare II (detection limit ≥3.3 µg/dL). Levels below detection were imputed by dividing the level of detection by √2. Associations between lead (quartiles) and systolic blood pressure and diastolic blood pressure were assessed, adjusting for age, sex, obesity, smoking, alcohol, physical activity, income, and antihypertensive medication use. The median age of participants was 40 years and 60.1% were female. The geometric mean blood lead level was 4.73µg/dL, 71.1% had a detectable lead level and 42.3% had a blood lead level ≥5 µg/dL. After multivariable adjustment, lead levels in quartile four (≥6.5 µg/dL) compared with quartile 1 (<3.4 µg/dL) were associated with 2.42 mm Hg (95% CI, 0.36–4.49) higher systolic blood pressure and 1.96 mm Hg (95% CI, 0.56–3.37) higher diastolic blood pressure. In conclusion, widespread environmental lead exposure is evident in urban Haiti, with higher lead levels associated with higher systolic and diastolic blood pressure. Lead is a current and potentially modifiable pollutant in lower-income countries that warrants urgent public health remediation. REGISTRATION URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03892265.
Background Men who have Sex with Men (MSM) represent the risk group that are disproportionately most affected by the human immunodeficiency virus (HIV) and continue to drop-off from the steps of the continuum of HIV services that have been adopted to overcome poor engagement and retention in care. This realist evaluation aimed at: (1) describing the evaluation carried out in Haiti aiming to ascertain why, how and under which circumstances MSM are linked and retained along the continuum, (2) assessing the outcomes of this approach and (3) exploring the motivators and facilitators for the HIV continuum of services through mechanisms and pathways. Methods Guided by a realist approach, first, an initial program theory (IPT) was developed based on literature and frameworks review, participant observations and discussions with stakeholders. Then, the IPT was tested using a mixed method explanatory study: a quantitative phase to build the continuum from a cross-sectional analysis, and a qualitative phase to explore the motivators and facilitators related to proper linkages along the continuum. Finally, the IPT was refined by eliciting the mechanisms and pathways for outcomes improvement. Results The results showed that the current service delivery model is suboptimal in identifying, engaging, linking and retaining MSM, resulting in loss to follow-up at every step of the continuum and failure to fully realize the health and prevention benefits of antiretroviral. However, the mechanisms through which linkages across the continuum can be improved are: self-acceptance, sense of community support and sense of comprehensive and tailored HIV services. These mechanisms are based on 10 different pathways: self-esteem, awareness and pride, perception of HIV risk, pcceptance and HIV status, addressing community stigma, strengthening of MSM organizations and community networks, societal acceptation and tolerance, stigma reduction training for healthcare providers, engagement of peers as educators and navigators and, adapted services delivery through drug dispensing points and mobile technology and financial assistance. Conclusions The study findings show that engagement, adherence and retention to the continuum of HIV service for MSM are affected by a multi-layer of factors, thus highlighting the importance of taking a comprehensive approach to improve the program.
There is a scarcity of studies that investigate the underlying factors that boost aspiring entrepreneurs to effectively start a business after attending entrepreneurship education (EE) programs, particularly in an adverse business environment. To fill out this gap, this exploratory research answers the following question: What differentiates business creators from non-creators among participants after entrepreneurship education? To answer this question, we compare a group of 64 business creators to a group of 50 non-business creators, both groups selected randomly among 912 participants to an EE program in Haiti three years after the end of the program. Based on an institutional perspective, our results show that, in the context of an adverse business environment, participants who came from a family with an entrepreneurial background, have a useful network of contacts, and showed adaptive institutional reaction were more likely to create their business, in comparison to the others. Based on these results suggestions for EE training and future studies are provided.
Soil mapping and characterization are extremely important, acting as a link between the preservation of the environment, sustainable agricultural practices as well as food-security, especially in one of the poorest and most food-insecure nations in the world. Soil mapping was carried out in the Mapou basin in the South-East Department of the Haiti, in order to contribute with the land use, agriculture planning, as well as soil conservation and food-security. Relationships with the different land uses and landscape attributes of the study area were determined. For this purpose, 24 soil profiles and three mini-trenches were dug, which were classified according to the World Reference Base for Soil Resources – WRB. In this region, the most representative soils were classified as following: Regosols, Leptosols, Cambisols, Luvisols, Lixisols, Calcisols, Fluvisols, Chernozems and Acrisols. Haplic Lixisoils are the deepest soil class in the region. All soils are strongly influenced by the properties of the parent material. Overall, soils are eutrophic with low levels of available phosphorus. Also, soils are weakly developed, shallow and strongly susceptible to erosive processes due to the steep slope and removal of the soil coverage. Data presented in this work will guide sustainable agricultural practices and soil management in the long-term scenario.
Background Men who have Sex with Men (MSM) represent the risk group that are disproportionately most affected by the human immunodeficiency virus (HIV) and continue to drop-off from the steps of the continuum of HIV services that have been adopted to overcome poor engagement and retention in care. This realist evaluation aimed at: 1) describing the evaluation carried out in Haiti aiming to ascertain why, how and under which circumstances MSM are linked and retained along the continuum, 2) assessing the outcomes of this approach and 3) exploring the motivators and facilitators for the HIV continuum of services through mechanisms and pathways. Methods Guided by a realist approach, first, an initial program theory (IPT) was developed based on literature and frameworks review, participant observations and discussions with stakeholders. Then, the IPT was tested using a mixed method explanatory study: a quantitative phase to build the continuum from a cross-sectional analysis, and a qualitative phase to explore the motivators and facilitators related to proper linkages along the continuum. Finally, the IPT was refined by eliciting the mechanisms and pathways for outcomes improvement. Results The results showed that the current service delivery model is suboptimal in identifying, engaging, linking and retaining MSM, resulting in loss to follow-up at every step of the continuum and failure to fully realize the health and prevention benefits of antiretroviral. However, the mechanisms through which linkages across the continuum can be improved are: self-acceptance, sense of community support and sense of comprehensive and tailored HIV services. These mechanisms are based on 10 different pathways: self-esteem, awareness and pride, perception of HIV risk, pcceptance and HIV status, addressing community stigma, strengthening of MSM organizations and community networks, societal acceptation and tolerance, stigma reduction training for healthcare providers, engagement of peers as educators and navigators and, adapted services delivery through drug dispensing points and mobile technology and financial assistance. Conclusions The study findings show that engagement, adherence and retention to the continuum of HIV service for MSM are affected by a multi-layer of factors, thus highlighting the importance of taking a comprehensive approach to improve the program.
As an ecotone, the region between the Amazon Rainforest and Tropical Savanna Cerrado) biomes is, by definition, more susceptible to climate change. Therefore, understanding palaeoenvironmental dynamics is essential to address the future responses of such transition areas to climatic fluctuations. In this context, we present a new sediment record for the Late-Holocene retrieved from Barro-Preto, currently an oxbow lake located in an ecotone at the southern Brazilian Amazon border. Our multi-proxy data include carbon and nitrogen isotopes, as well as bulk TOC, chlorophyll derivatives, grain-size and microcharcoal analyses, all anchored on a radiocarbon-dated chronology. The sedimentary process recorded at the Barro-Preto Lake responded to both local and regional climate dynamics. It was influenced by river excursions associated to local responses to precipitation changes by the activation of the palaeochannel connecting the main-stem river and the Barro-Preto lake. This activation was evidenced by the presence of different colour lithology laminations accompanied by coarser sediments and also by climate conditions known to influence the Amazon region. Depositional processes linked to lake dynamics and different oxbow lake cycle stages were also important to explain the changes verified in the Barro-Preto record, endorsing the use of this lake formation for palaeoclimatic reconstructions. The record indicated a rising humidity trend, reflected by a progressive increase in lacustrine productivity, in accordance to other studies carried out in the Amazon region concerning the Late-Holocene, associated with a more southward displacement of the Intertropical Convergence Zone. Despite this rising humidity trend, dry episodic events during the Late-Holocene were evidenced by charcoal data, also coherent with regional Amazon studies, albeit exhibiting increased intensity, suggesting that the transitional nature of the environment might have influenced susceptibility to fires.
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