Implications of fuel poverty for indoor black carbon concentrations from space heating.

Despite the global transition towards cleaner energy sources observed over the last decade, disparities in access to clean energy persist worldwide. The dependence on biomass for household heating exacerbates fuel poverty, as economically vulnerable households face challenges in obtaining certified firewood and often resort to using contaminated biomass as a substitute, either partially or completely. We examined black carbon (BC) particle concentrations -a marker for combustion- during wood stove operation through a five-day case study in a typical Chilean household. BC increased rapidly following the ignition of the stove, with the combustion of dry Eucalyptus globulus logs yielding a substantially lower peak (5.29 µg/m3) than when using unclean biomass: 35.75 µg/m3 with demolition wood and painted furniture, and 87.11 µg/m3 with the addition of a blend of particleboard with polystyrene foam. During the latter two events, BC particles remained indoors for about 20 h before the concentrations reverted to pre-spike levels. The slow decay in BC concentrations was further influenced by the infiltration of outdoor air. The mean indoor BC concentrations were comparable to or even exceeded those observed on busy roads in major cities worldwide. These results highlight the risks associated with limited access to clean fuels for indoor heating, alongside inadequate insulation. This study sheds light on the problem of fuel poverty and its adverse effects on health and well-being.

Biocultural heritage of the Caatinga: a systematic review of Myrtaceae and its multiple uses.

The Caatinga, an exclusively Brazilian biome, stands as a reservoir of remarkable biodiversity. Its significance transcends ecological dimensions, given the direct reliance of the local population on its resources for sustenance and healthcare. While Myrtaceae, a pivotal botanical family within the Brazilian flora, has been extensively explored for its medicinal and nutritional attributes, scant attention has been directed towards its contextual relevance within the Caatinga's local communities. Consequently, this inaugural systematic review addresses the ethnobotanical roles of Myrtaceae within the Caatinga, meticulously anchored in the PRISMA 2020 guidelines. We searched Scopus, MEDLINE/Pubmed, Scielo, and LILIACS. No date-range filter was applied. An initial pool of 203 articles was carefully scrutinized, ultimately yielding 31 pertinent ethnobotanical studies elucidating the utility of Myrtaceae amongst the Caatinga's indigenous populations. Collectively, they revealed seven distinct utilization categories spanning ~54 species and 11 genera. Psidium and Eugenia were the genera with the most applications. The most cited categories of use were food (27 species) and medicinal (22 species). The importance of accurate species identification was highlighted, as many studies did not provide enough information for reliable identification. Additionally, the potential contribution of Myrtaceae fruits to food security and human health was explored. The diversity of uses demonstrates how this family is a valuable resource for local communities, providing sources of food, medicine, energy, and construction materials. This systematic review also highlights the need for more ethnobotanical studies to understand fully the relevance of Myrtaceae species in the Caatinga, promoting biodiversity conservation, as well as support for local populations.

Emission of volatile organic compounds during open fire cooking with wood biomass: Traditional three-stone open fire vs. gasifier cooking stove in rural Kenya.

Cooking with wood biomass fuels releases hazardous air pollutants, including volatile organic compounds (VOCs), that often disproportionally affect women and children. This study, conducted in Kwale and Siaya counties in Kenya, employed thermal desorption gas chromatography - mass spectrometry to analyse VOC emissions from cooking with a wood biomass three-stone open fire vs. top-lit updraft gasifier stove. In kitchens with adequate ventilation, total VOC levels increased from 35-252 µg∙m-3 before cooking to 2235-5371 µg∙m-3 during open fire cooking, whereas use of a gasifier stove resulted in reduced emissions from cooking by 48-77 % (506-2778 µg∙m-3). However, in kitchens with poor ventilation, there was only a moderate difference in total VOC levels between the two methods of cooking (9034-9378 µg∙m-3 vs. 6727-8201 µg∙m-3 for the three-stone open fire vs. gasifier stove, respectively). Using a non-target screening approach revealed significantly increased levels of VOCs, particularly benzenoids, oxygenated and heterocyclic compounds, when cooking with the traditional open fire, especially in closed kitchens, highlighting the effects of poor ventilation. Key hazardous VOCs included benzene, naphthalene, phenols and furans, suggesting potential health risks from cooking. In kitchens with good ventilation, use of the gasifier stove markedly reduced emissions of these priority toxic VOCs compared to cooking with an open fire. Thus, substituting open fires with gasifier stoves could help to improve household air quality and alleviate health risks. The study revealed that VOCs were present prior to cooking, possibly originating from previously cooked food (buildup) or the outside environment. VOC emissions were also exacerbated by reduced air flow in high humidity during rainfall, suggesting an area for further research. The findings underscore the importance of adopting cleaner cooking technologies and enhancing kitchen ventilation to mitigate the impacts of VOCs in developing countries.

Contamination and persistence of polycyclic aromatic hydrocarbons (PAHs) in rice grains after drying in direct-fired dryer.

The objective of this work was to study PAHs contamination in rice grains subjected to different milling types, after drying at different air temperatures in a direct-fired dryer and using firewood with different moisture contents as a heating source. In addition to verifying the persistence of these compounds after storage. Drying of rice grains was performed in a cross-flow dryer at air temperatures of 55 and 65 ºC. As heating source firewood containing different moisture contents was used. The presence of nine PAHs was detected. The drying air temperature, as well as the storage time, did not significantly influence the PAHs contamination of grains. The highest PAHs contamination was observed in grains from the brown subgroup. Grain polishing promoted a reduction in the PAH concentration. The grains subjected to parboilization showed a higher PAHs concentration. The use of firewood with higher moisture content promoted greater PAHs contamination in the grains.

Forecasted data of prices for the most common households' fuels utilized in Nigeria during the period 2010-2024.

The most common household fuel utilized in the six geopolitical zones of Nigeria is kerosene, liquified petroleum of gas (LPG), firewood, charcoal, and electricity. These energy commodities are contributing to simplify people's life. They are used in satisfying energy demands such as cooking, heating, and lighting for every single home. The energy prices were collected from 2010 to 2021, and we forecasted from 2022 to 2024. There is data available from 2010-2021 about prices for some of these commodities, but they are scattered, narrow, and in some cases, there is just a general-referred value for the whole nation and only for a single year from the past. These situations have limited the development of economic studies which undertake analyses regarding consumers' behavior. The forecasted fares for kerosene and LPG were calculated under the basis of accessible information but limited by the National Bureau of Statistics of Nigeria. The available electricity tariffs were collected from the Nigerian Electricity Regulatory Commission from the existing eleven private electricity distribution companies (DISCOS). In the case of firewood and charcoal, the costs were estimated departing from the research work of Gujba et al. [1]. In the second part, we specify the way how data was obtained and its treatment for specific time periods. The statistics include the values for each fuel in the different geopolitical regions and for the most popular presentations available to the end customers. The forecasting was developed for past and future years during the under-study period of time. The information presented in the article refers to the research study: Urban and rural household energy transition in Sub-Saharan Africa: Does spatial heterogeneity reveal the direction of the transition?

Drivers of household demand for cooking energy: A case of Central Uganda.

In Uganda, the total primary household energy consumption is mainly biomass. Lack of empirical information remains a daunting challenge to operationalization of strategies and policies aimed at reducing unsustainable energy use. This study specifically determined household demand for different cooking energy sources (briquettes, charcoal and firewood). Data were collected from a sample of 235 households with the help of pretested structured questionnaires. Data were analyzed using descriptive statistics and Seemingly Unrelated Regression (SUR). From the econometric analysis, results revealed that briquettes demand was significantly influenced by fuel expenditure, briquette price, gender of household head, main occupation and source of fuel. Further, charcoal demand was influenced by fuel expenditure, household size, charcoal price, district and fuel restriction. On the other hand, demand for firewood was influenced by household income, firewood price, fuel expenditure, household size and source of the fuel. From our findings, it is recommended that tailored trainings on sustainable exploitation of biomass resources for energy supply should be conducted across the country. In addition, there is need for such trainings to target women, who are the decision makers with respect to household energy supply. Lastly the study recommends the need for low-cost briquetting technologies that would reduce its price to levels that are competitive to charcoal and firewood.

Cooking stoves and risk of congenital heart disease in Northwest China: A case-control study.

Congenital heart disease (CHD) has become the most common birth defect in recent decades. The aim of our study was to examine the association between stove cooking by women during pregnancy and congenital heart disease in their offspring. To address this question, we conducted a case-control study from 2014 to 2016 in Xi'an, Shaanxi, Northwest China, investigating 326 cases and 1071 controls. The cases included fetuses or newborns diagnosed with CHD based on the International Classification of Disease (ICD)-10. Controls consisted of healthy newborns without birth defects. Multivariate unconditional logistic regression was applied to analyze the effects of stove cooking before and during pregnancy on CHD in offspring. After adjusting for confounding factors, we found that, compared to cooking with gas stoves, electromagnetic, coal, and firewood stoves during pregnancy was associated with increased risk of CHD in offspring [electromagnetic stove (odds ratio (OR): 2.89, 95% confidence interval (CI): 2.02, 4.12); coal stove (OR: 3.94, 95% CI: 2.33, 6.65); firewood stove (OR: 6.74, 95% CI: 3.03, 15.00)]. Additionally, higher cooking frequency was associated with increased risk of CHD [total stoves (OR: 2.27, 95% CI: 1.57, 3.28); gas stove (OR: 2.38, 95% CI: 1.43, 3.95); electromagnetic stove (OR: 2.46, 95% CI: 1.32, 4.58); coal and firewood stoves (OR: 3.09, 95% CI: 1.01, 9.46)]. Our study suggests that using electromagnetic, coal, and firewood stoves for cooking during pregnancy and greater cooking frequency increased the risk of CHD in offspring. More attention to the choice of fuels in cooking by pregnant women would help to reduce the incidence of CHD in children.

Impacts of firewood burning for cooking on respiratory health and healthcare utilisation: Empirical evidence from Sri Lankan micro-data.

Despite escalating income levels of Sri Lankan households, 70.3% of them still depend on firewood for cooking. This might lead to bad respiratory health and thereby, increased healthcare utilisation. With this backdrop, this paper examines how firewood burning for cooking influences respiratory health and healthcare utilisation of Sri Lankans. The study proposes a theoretical model to explain effects of firewood burning on respiratory health and healthcare utilisation and empirically tests it using nation-wide micro-data of 79,170 individuals belonging to 21,748 households. The data are drawn from the most recent wave of Sri Lankan household income and expenditure survey. After addressing potential endogeneity by applying instrumental variable regression models, the study finds that firewood burning increases households' probability of asthma prevalence by 10.9 percentage points (P < 0.001), out-patient care utilisation by 33.1 percentage points (P < 0.001), and in-patient care utilisation by 17.5 percentage points (P < 0.001), on average. Our individual level analysis demonstrates that females are more vulnerable to bad respiratory health induced by firewood burning (ß = 0.055, P < 0.001) compared to males (ß = 0.008, P > 0.1). The results imply policies on promoting improved-cooking stoves, separated-kitchen designs, and switching more towards cleaner energy sources, including LP gas and solar power.

The cost of cooking for foragers.

Cooked food provides more calories to a consumer than raw food. When our human ancestors adopted cooking, the result was an increase in the caloric value of the diet. Generating the heat to cook, however, requires fuel, and accessing fuel was and remains a common problem for humanity. Cooking also frequently requires monitoring, special technology and other investments. These cooking costs should vary greatly across multiple contexts. Here I explain how to quantify this cooking trade-off as the ratio of the energetic benefits of cooking to the increased cost in handling time and examine the implications for foragers, including the first of our ancestors to cook. Ethnographic and experimental return rates and nutritional analysis about important prey items exploited by ethnohistoric Numic foragers in the North American Great Basin provide a demonstration of how the costs of cooking impact different types of prey. Foragers should make choices about which prey to capture based on expectations about the costs involved to cook them. The results indicate that the caloric benefit achieved by cooking meat is quickly lost as the cost of cooking increases, whereas many plant foods are beneficially cooked across a range of cooking costs. These findings affirm the importance of plant foods, especially geophytes, among foragers, and are highly suggestive of their importance at the onset of cooking in the human lineage.

Determinants of Household Energy Choice for Cooking in Northern Sudan: A Multinomial Logit Estimation.

Traditional biomass utilization is connected with negative environmental and human health impacts. However, its transition to cleaner cooking fuels is still low where the household's fuels preferences play an important role in the process. To examine the factors that influence the household's cooking fuel choice in Northern Sudan, a multinomial logit model (MNL) was used to analyze data collected from Kassala state in two selected districts, New Halfa and Nahr Atabara. The findings show that the most utilized fuels are still firewood and charcoal, which are used by 63.4% of all respondents. The results also revealed that socioeconomic factors have an impact on household fuel choice, where one additional unit of credit access may boost the possibility of choosing LPG by 22.7%. Furthermore, one additional level of education would reduce 5.4% of charcoal users while simultaneously raising 10% of current liquefied petroleum gas (LPG) users. Therefore, the study suggests initiating mobilization and training programs to raise awareness and encourage the usage of cleaner fuels. This study will provide policymakers with information on household cooking energy utilization while designing and developing policies related to energy. It will also contribute to the expanding body of literature concerning the transition to clean cooking fuels from traditional biomass.

Firewood Transport as a Vector of Forest Pest Dispersal in North America: A Scoping Review.

Native and nonnative insects and diseases can result in detrimental impacts to trees and forests, including the loss of economic resources and ecosystem services. Increases in globalization and changing human behaviors have created new anthropogenic pathways for long distance pest dispersal. In North America, literature suggests that once a forest or tree pest is established, the movement of firewood by the general public for recreational or home heating purposes is one of the primary pathways for its dispersal. Understanding human perceptions and behaviors is essential to inform the most effective strategies for modifying firewood and pest dispersal by humans. This scoping review seeks to assess trends and gaps in the existing literature, as well as patterns in behavior related to forest pest dispersal through firewood movement in North America. We identified 76 documents that addressed this topic to which we applied inclusion and exclusion criteria to select articles for further analysis. Twenty-five articles met the inclusion criteria and were categorized based on five identified themes: 1) insect incidence in firewood, 2) insect dispersal via firewood, 3) recreational firewood movement, 4) firewood treatments, and 5) behavior and rule compliance. The selected articles show trends that suggest that firewood movement presents a risk for forest insect dispersal, but that behavior can be modified, and compliance, monitoring, and treatments should be strengthened. This scoping review found limited research about western United States, Mexico, and Canada, various insect species and other organisms, regulation and management, awareness, and behavioral dimensions of firewood movement.

Exposure levels to PM2.5 and black carbon for people with disabilities in rural homes of Colombia.

Indoor exposure to air pollutants emitted by solid fuels used for cooking or heating homes remains as a problem to solve. The most affected people are newborns, mothers, children, and people with disabilities, due to the time they spend at home. This study is the first in a rural area of South America, which measures indoor air pollutants (PM2.5 and black carbon) in different environments, inhabited by people with disabilities. The research was supported through a sociodemographic characterization, a methodology useful for future studies, continuous monitoring for 72 h of pollutants, and emission sources, cooking habits, and pre-existing diseases were identified. The primary sources of emissions are improved wood-burning stoves and their chimney. In households where firewood is used, the average concentrations of PM2.5 were the highest (between 10.9 and 3302.5 µg/m3), as were the average concentrations of BC (average 72 h between 2.6 and 51.2 µg/m3) compared with the houses that use gas (average 72 h between 2.6 and 6 µg/m3). In 57% of the households visited, the World Health Organization (WHO) guidelines for PM2.5 (25 µg/m3 for 24 h) were exceeded. The results reveal that rural concentrations of BC can be up to 2.5 times higher than those of an urban area with high vehicular traffic and high population density and could be used to establish a baseline that allows the implementation of control mechanisms to reduce pollution of indoor air.

The Marine Isotope Stage 3 landscape around Manot Cave (Israel) and the food habits of anatomically modern humans: New insights from the anthracological record and stable carbon isotope analysis of wild almond (Amygdalus sp.).

The excavation of Manot Cave (Israel) reveals intensive occupation during the Early Upper Paleolithic and provides the first continuous set of anthracological data available for the Ahmarian, Levantine Aurignacian and post-Levantine Aurignacian periods. The paper aims to study the vegetal landscape around Manot Cave in the context of climate changes that characterized the last part of the Marine Isotope Stage 3 (MIS 3) and to address the issue of firewood and food procurement among Paleolithic hunter-gatherers. Charcoal samples recovered from the archaeological layers at Manot Cave shed light on the fuel and food procurement strategies while radiocarbon dating and stable carbon isotope analysis (Δ13C) of selected charcoals provide information about the ancient climate. The results show that five woody taxa were exploited at the site; Amygdalus sp. was the most common species, whereas Quercus ithaburensis, Tamarix sp., Pomoideae indet., and Pistacia atlantica were relatively rare. The representations of the recovered wooden species suggest that an open forest of almonds and oaks existed in the area during MIS 3. Radiocarbon dating of Amygdalus sp. charcoals, coupled with stable carbon isotope analysis (Δ13C) of modern and archaeological Amygdalus sp. clearly indicate variations in rainfall that could have decreased the density of tree cover. These analyses provide high-resolution data on the climate changes affecting the surroundings of Manot Cave between ∼46 and 28 ka cal BP and indicate two drier phases corresponding to the Ahmarian and post-Levantine Aurignacian cultures while a more humid period identified during the Levantine Aurignacian.

Ensembles of ecosystem service models can improve accuracy and indicate uncertainty.

Many ecosystem services (ES) models exist to support sustainable development decisions. However, most ES studies use only a single modelling framework and, because of a lack of validation data, rarely assess model accuracy for the study area. In line with other research themes which have high model uncertainty, such as climate change, ensembles of ES models may better serve decision-makers by providing more robust and accurate estimates, as well as provide indications of uncertainty when validation data are not available. To illustrate the benefits of an ensemble approach, we highlight the variation between alternative models, demonstrating that there are large geographic regions where decisions based on individual models are not robust. We test if ensembles are more accurate by comparing the ensemble accuracy of multiple models for six ES against validation data across sub-Saharan Africa with the accuracy of individual models. We find that ensembles are better predictors of ES, being 5.0-6.1% more accurate than individual models. We also find that the uncertainty (i.e. variation among constituent models) of the model ensemble is negatively correlated with accuracy and so can be used as a proxy for accuracy when validation is not possible (e.g. in data-deficient areas or when developing scenarios). Since ensembles are more robust, accurate and convey uncertainty, we recommend that ensemble modelling should be more widely implemented within ES science to better support policy choices and implementation.

Time Use Implication of Clean Cookstoves in Rural Settings in Ghana: A Time Use Study.

Whilst the health benefit of using clean cookstoves and fuels is widely known, there is limited information on the non-health benefit of these stoves, especially in low-middle-income countries. This paper reports the time use implications of using clean cookstoves and fuels by comparing liquified petroleum gas (LPG), an improved biomass cookstove (BioLite), and traditional biomass cookstoves (three-stone fires) in Ghana. Using survey-based time diaries, information on all the activities undertaken by study participants during a 24-h was collected and analyzed. The findings of the study show that LPG users spent significantly less time gathering firewood compared to the users of improved cookstoves and three-stone fires. LPG users spent slightly less time per cooking episode, generally, and there was no significant difference in cooking time across the three cookstoves mostly due to stove stacking. Time spent engaging in economic activities was highest for LPG users and improved biomass cookstove users, at least when compared to three-stone fire users. In this study, we provide evidence on the time use implications of clean cookstoves, highlighting their non-health benefits and supporting efforts towards the adoption and sustained used of clean cookstoves.

Exposure to air pollutants and heat stress among resource-poor women entrepreneurs in small-scale cassava processing.

Exposure to air pollutants and heat stress from traditional cooking fires is the leading cause of mortality and morbidity in low- and middle-income countries globally and have an adverse effect on the environment. According to the World Health Organization, 3.8 million people die annually prematurely from illness related to household air pollution. Families living in poverty are at the highest risk, especially women and children. In this study, exposure to particulate matter (PM2.5 and PM10), carbon monoxide (CO) and nitrogen dioxide (NO2) was measured among resource-poor women cassava processors. The test locations were chosen in the peri-urban settlements of Abeokuta in the Ogun State of Nigeria, where household women entrepreneurs roast garri (granulated cassava) for sale in the local market. The measurements were taken for two types of stoves which are generally existing in the study location. First, a rectangular stove (RS) with two operators and, second, a circular stove (CS) with one operator; both stoves used wood as fuel. The emissions were compared with a modern mechanical liquefied petroleum gas burner-based garri roaster (GS). Hours spent per day in front of garri stoves ranged from 6 to 12 h for both stoves, with a frequency of 1 to 3 days of operation per week. It was found that CS operators were spending significantly more time in producing garri, which is due to the low capacity of the CS. The average PM2.5 concentrations for RS and CS were 381 and 273 µg/m3, respectively, estimated to be 21 and 41 µg/m3 on an annual mean level basis. Similarly, for PM10, the mean concentration levels were 1580 and 594 µg/m3 for RS and CS, respectively. The annual mean levels for PM10 were about 89 µg/m3 for both types of stoves. CO exposure during garri processing was up to five times higher than the recommended concentrations with a 4-h mean of 48 and 50 mg/m3 for RS and CS, respectively. NO2 levels were very low, ~ 0 ppm. This investigative research concluded that wood-fired small-scale garri producers in Nigeria are exposed to very unhealthy levels of PM, CO and thermal stress. The concentration levels of both PM and CO were exceeding the global as well as Nigerian ambient air quality standard regulations. Along with air pollution, thermal stress was a significant issue, which is known to exacerbate the negative effect of air pollution on the human body.

Exposição ao uso da lenha para cocção no Brasil e sua relação com os agravos à saúde da população / Exposure to the use of firewood for cooking in Brazil and its relation with the health problems of the population

Resumo A poluição do ar em ambientes fechados é agravada pela queima de lenha em fogões rústicos e ambientes pouco ventilados. A exposição aos poluentes emitidos por este tipo de combustível resulta no aumento da morbidade e da mortalidade. No Brasil, os estudos e as estimativas são escassos. Visando entender esta problemática, o objetivo deste trabalho foi investigar o uso de lenha utilizando as séries de dados das agências governamentais para estimar o número de pessoas expostas. Os resultados apontam que a lenha é o segundo combustível mais usado para cozinhar, sendo utilizada por uma parcela significativa da população, em torno de 30 milhões de brasileiros. Um fator decisivo no maior uso deste combustível é o nível socioeconômico da população associada ao preço do gás liquefeito de petróleo (GLP). Os estudos realizados no país registraram concentrações altas de partículas durante a queima da lenha, excedendo os limites sugeridos pela Organização Mundial da Saúde (OMS). Também foram observadas associações entre a exposição aos poluentes gerados pela queima e o agravamento dos mais diversos problemas de saúde, dentre eles doenças respiratórias e câncer. A substituição da lenha e outros combustíveis sólidos por combustíveis mais limpos deve ser a meta do governo para minimizar custos com a saúde.

Abstract Indoor air pollution is exacerbated by the burning of firewood in rustic stoves and poorly ventilated environments. Exposure to the pollutants emitted by this type of fuel results in increased morbidity and mortality. In Brazil, studies and estimates regarding these conditions are scarce. In order to understand this problem, the objective of this work was to investigate the use of firewood using the data series of government agencies to estimate the number of exposed people. The results indicated that firewood is the second most used fuel for cooking, being used by a significant portion of the population, more than 30 million Brazilians. A decisive factor in the increased use of this fuel is the socioeconomic level of the population associated with the price of liquefied petroleum gas (LPG). The studies carried out in the country recorded high concentrations of particles during firewood burning, exceeding the limits suggested by the World Health Organization (WHO). Associations were also observed between the exposure to the pollutants generated by the burning and the aggravation of health problems, among them respiratory diseases and cancer. Replacing fuelwood and other solid fuels with cleaner fuels should be the government's goal to minimize health costs.

Prevalence and determinants of depression in mothers of children under 5 years in Bole District, Ghana.

OBJECTIVE: Depression in mothers is a risk factor for poor health, and pregnancy and child outcomes. The objective of the present study was to determine the prevalence of depression and identify its determinants in mothers of children under 5 years in Bole District, Ghana. RESULTS: We conducted an analytical cross-sectional study consisting of 244 mothers (mean age 28.7 ± 6.29 years) in Bole District, Ghana. Edinburgh Postnatal Depression Scale was used to screen for depression and the determinants of depression were identified using logistic regression analysis. The prevalence of depression in this study population was 16.8% (95% confidence interval 12.1-22.0%). The independent determinants of depression were marital status, occupation, lighting source and type of cooking fuel. Being currently unmarried (p < 0.001), and using lighting sources other than electricity (p = 0.004) were associated with higher risk of depression while being employed in other occupations (p = 0.001), and not cooking with firewood (p = 0.008) were associated with lower risk of depression. In this study population, the prevalence of depression was relatively high in mothers and was associated with marital status, occupation, lighting source and cooking fuel. Interventions to prevent and treat depression in women should include strategies to improve their socio-economic status and living conditions.

Livelihood benefits and costs from an invasive alien tree (Acacia dealbata) to rural communities in the Eastern Cape, South Africa.

The negative effects of invasive alien species (IAS) are increasingly invoked to justify widespread and usually top-down approaches for their management or eradication. However, very little of the research or discourse is based on investigating local perceptions, uses and struggles with IAS, and how their presence influences and changes local livelihoods. The objective of this study was to assess the perceptions and livelihood uses of Acacia dealbata by local communities at three localities in the montane grasslands of the Eastern Cape, South Africa, using a combination of random household interviews, focus group discussions and participatory tools. We calculated direct-use values for each product and household (based on quantity used and local prices) and disaggregated these by gender of the household head and wealth quartiles. The results revealed the dualistic role of A. dealbata in local livelihoods. On the one hand, A. dealbata was widely used for firewood (100% of households), tools (77%) and construction timber (73%), with limited use for traditional medicines and forage. The cumulative value of approximately ZAR 2870 (±US$224) per household per year (across all households) represents considerable cash saving to households, most of whom are quite poor by national and international measures. On the other hand, the increasing extent of A. dealbata (93% said it was increasing) exacerbates local household vulnerability though reported reductions in cultivated areas, crop yields and forage production, and allegedly higher risks of crime. This quandary is well encapsulated by the considerable majority of respondents (84%) not wanting higher extents and densities of A. dealbata, but an equally high majority not wanting its total removal from local landscapes. Most respondents disliked A. dealbata in fields, close to homesteads or along primary access routes, and were more tolerant of it away from such sites. Institutional and use dynamics have varied over several decades in response to the changing extent and densities of A. dealbata and the broader political and socio-economic contexts. These results indicate that greater efforts are required to understand perceptions and uses of IAS by the people who live with them, and to direct such understanding into more spatially and temporally contextualised response strategies where required.

Características e procedência da lenha usada na cocção no Brasil / Characteristics and procedures of firewood used in cooction in Brazil

A lenha vem sendo substituída ao longo dos anos por novas formas de energia, como o gás liquefeito de petróleo (GLP) e a eletricidade. Porém, esse combustível ainda representa uma fração significativa da matriz energética brasileira, muito embora as pesquisas referentes ao seu uso ainda sejam limitadas e regionais. O objetivo deste estudo foi realizar um levantamento da produção, consumo e características da lenha usada com a finalidade de cocção. De acordo com os resultados, em 2016, 26,5% da lenha produzida no Brasil foram empregados com fins residenciais, ou seja, em torno de 2x107 toneladas. A lenha é proveniente tanto da silvicultura, sendo o Paraná o maior produtor, quanto do extrativismo, sendo a Bahia a maior produtora. O estado que apresenta maior dependência desse combustível para a cocção é o Pará, enquanto o Rio de Janeiro, praticamente, não a usa para esse fim. O consumo per capita varia muito de uma região a outra do país. Com base nos dados de 2016, foi estimado um consumo de 1,7 kg/pessoa/dia. No entanto, estudos in loco mostraram variação de 0,7 a 8,5 kg/pessoa/dia. O levantamento aponta que uma parte considerável da lenha é proveniente de matas nativas que têm reflexos no desmatamento de uma dada região. A pouca disponibilidade de dados e a variação entre eles impede uma avaliação mais precisa do uso deste combustível no país e suas implicações para a saúde das florestas. A implantação de políticas públicas deveria ser prioridade do governo, pois o uso da lenha de forma inadequada afeta o manejo da vegetação nativa, além de ser uma questão socioambiental, econômica e de saúde pública.

Firewood has been replaced over the years by new forms of energy, such as liquefied petroleum gas (LPG) and electricity. However, this fuel still accounts for a significant fraction of the Brazilian energy matrix. Research regarding its use remains limited and regional in the country. The objective of this study was survey the production, consumption and characteristics of firewood used for cooking. According to the results, in 2016 26.5% of the firewood produced in Brazil was used for residential purposes, around 2×107 metric tons. Firewood comes from both silviculture, Paraná being the largest producer, and extractivism, Bahia being the largest producer. Pará presented the greatest dependence of this fuel, while Rio de Janeiro practically does not use it for this purpose. Per capita consumption varies from one region to another. Based on data from 2016, it was estimated that consumption was 1.7 kg/person/day. In situ studies showed consumption ranges from 0.7 to 8.5 kg/person/day. The study shows an obvious reliance on native forests to obtain firewood, resulting in deforestation in some areas. The low availability of data and the variation among them prevents a better assessment of the use of this fuel in Brazil and the implications for forest health. The im-plementation of public policies should be a priority of the government, as the improper use of firewood negatively affects the management of native vegetation, as well as being a socio-environmental, economic and public health burden.