Influence of Socioeconomic Factors on the Knowledge and Consumption of Firewood in the Atlantic Forest of Northeast Brazil

Economic Botany - We aim to evaluate whether socioeconomic factors influence the knowledge, use, preference, and consumption of firewood in a rural community in Northeast Brazil. We conducted...     

Circulating soluble endoglin levels in pregnant women in Cameroon and Malawi--associations with placental malaria and fetal growth restriction

Placental infections with Plasmodium falciparum are associated with fetal growth restriction resulting in low birth weight (LBW). The mechanisms that mediate these effects have yet to be completely described; however, they are likely to involve inflammatory processes and dysregulation of angiogenesis. Soluble endoglin (sEng), a soluble receptor of transforming growth factor (TGF)-β previously associated with preeclampsia in pregnant women and with severe malaria in children, regulates the immune system and influences angiogenesis. We hypothesized that sEng may play a role in development of LBW associated with placental malaria (PM). Plasma levels of sEng were measured in women (i) followed prospectively throughout pregnancy in Cameroon (n = 52), and (ii) in a case-control study at delivery in Malawi (n = 479). The relationships between sEng levels and gravidity, peripheral and placental parasitemia, gestational age, and adverse outcomes of PM including maternal anemia and LBW were determined. In the longitudinal cohort from Cameroon, 28 of 52 women (54%) experienced at least one malaria infection during pregnancy. In Malawi we enrolled two aparasitemic gravidity-matched controls for every case with PM. sEng levels varied over the course of gestation and were significantly higher in early and late gestation as compared to delivery (P<0.006 and P<0.0001, respectively). Circulating sEng levels were higher in primigravidae than multigravidae from both Cameroon and Malawi, irrespective of malarial infection status (p<0.046 and p<0.001, respectively). Peripheral parasitemia in Cameroonian women and PM in Malawian women were each associated with elevated sEng levels following correction for gestational age and gravidity (p = 0.006 and p = 0.033, respectively). Increased sEng was also associated with the delivery of LBW infants in primigravid Malawian women (p = 0.017); the association was with fetal growth restriction (p = 0.003) but not pre-term delivery (p = 0.286). Increased circulating maternal sEng levels are associated with P. falciparum infection in pregnancy and with fetal growth restriction in primigravidae with PM.     

Firewood management and woodland exploitation during the late Neolithic at Lac de Chalain (Jura,France)

The paper presents results of the charcoal analysis from the lakeshore settlement of Chalain 4 in the French Jura (Dép. Franche-Comté), dated by dendrochronology from 3040 to 3000 bc. The investigated material comes from waterlogged organic layers (excluding fire events) where charcoals are assumed to be the residues of domestic fires only. The anthracological (charcoal) analysis reveals a complex domestic firewood management in balance with the social organisation and the technical and economic systems of the settlement. This firewood economy is characterised by the avoidance of wood species intended for other activities, such as building or foddering, and by the preferential use of wood less than 10 cm in diameter. The areas from which firewood was obtained are also connected to woodland clearance for cultivated land, which suggests that firewood was gathered along the paths, which were travelled daily.     

丽江市家庭能耗碳排放特征及影响因素

现代社会中人类活动对碳排放的影响日益显著.家庭作为人类社会的基本单元,其消费活动产生的碳排放是全社会碳排放的重要组成部分.通过对丽江市农村和市区家庭生活用能的调查数据进行分析,发现农村家庭生活用能以木柴为主,沼气和电为辅;市区家庭的生活用能以电为主,其次是液化气和蜂窝煤.从碳排放构成来看,农村地区木柴消费为家庭能源碳排放的主要来源,占总碳排的83.6％;市区电力消费为家庭能源碳排放的主要来源,占总碳排的88.4％.农村地区家庭的碳排放远高于市区家庭,主要原因是木柴的碳排放因子(1.87 kg CO2/kg)远高于电能的边际排放因子(0.7134 kg CO2·kW-1·h-1).从各影响因素与家庭主要能源消费碳排放的回归结果来看,在农村地区,家庭规模、家庭收入、教育水平均对家庭木柴消费碳排放有显著的影响,但影响方向和程度有一定的差别;在市区,年龄结构、教育水平、家庭规模、住房面积均会不同程度增加家庭电能消费碳排放.建议政府在完善“家电下乡”政策、增加农村家庭收入、加强农村居民教育等方面加大投入力度,以减少丽江市整体的家庭能耗碳排放.     

农户薪柴消费的理论模型及实证研究

农户薪柴消费变化对室内空气质量、农村生态环境建设影响重大,论文构建了山区农户薪柴消费的理论模型,以重庆市典型区1015份农户调查数据为例,运用Tobit模型分析了农户人均薪柴消费量的影响因素。研究表明:农户家庭能源消费中,商品能源和新能源的比重逐步增大,但薪柴依旧是农户普遍使用的能源类型,且消费量占总能源消费量的比重高;通过降低农业劳动力比重和提高非农工资水平两种途径,非农就业能显著降低农户人均薪柴消费量;家庭电器数量增多、其他收入(政府补贴、亲戚帮扶等)增加、及替代能源(液化气、沼气、煤炭等)可获得性增强也能显著降低农户人均薪柴消费量,而户主年龄大、人均牲畜数量多及房屋离集市距离远的农户家庭的人均薪柴消费量高。提出了加快薪柴替代的措施。     

Modelling Interactions between Forest Pest Invasions and Human Decisions Regarding Firewood Transport Restrictions

The invasion of nonnative, wood-boring insects such as the Asian longhorned beetle (A. glabripennis) and the emerald ash borer (A. planipennis) is a serious ecological and economic threat to Canadian deciduous and mixed-wood forests. Humans act as a major vector for the spread of these pests via firewood transport, although existing models do not explicitly capture human decision-making regarding firewood transport. In this paper we present a two-patch coupled human-environment system model that includes social influence and long-distance firewood transport and examines potential strategies for mitigating pest spread. We found that increasing concern regarding infestations (f) significantly reduced infestation. Additionally it resulted in multiple thresholds at which the intensity of infestation in a patch was decreased. It was also found that a decrease in the cost of firewood purchased in the area where it is supposed to be burned (C _l) resulted in an increased proportion of local-firewood strategists, and a 67% decrease in C _l from $6.75 to $4.50 was sufficient to eliminate crosspatch infestation. These effects are synergistic: increasing concern through awareness and education campaigns acts together with reduced firewood costs, thereby reducing the required threshold of both awareness and economic incentives. Our results indicate that the best management strategy includes a combination of public education paired with firewood subsidization.     

Colony social organization and population genetic structure of an introduced population of formosan subterranean termite from New Orleans, Louisiana

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an invasive species in many parts of the world, including the U.S. mainland. The reasons for its invasive success may have to do with the flexible social and spatial organization of colonies. We investigated the population and breeding structure of 14 C. formosanus colonies in Louis Armstrong Park, New Orleans, LA. This population has been the focus of extensive study for many years, providing the opportunity to relate aspects of colony breeding structure to previous findings on colony characteristics such as body weight and number of workers, wood consumption, and intercolony aggression. Eight colonies were headed by a single pair of outbred reproductives (simple families), whereas six colonies were headed by low numbers of multiple kings and/or queens that were likely the neotenic descendants of the original colony (extended families). Within the foraging area of one large extended family colony, we found genetic differentiation among different collection sites, suggesting the presence of separate reproductive centers. No significant difference between simple family colonies and extended family colonies was found in worker body weight, soldier body weight, foraging area, population size, or wood consumption. However, level of inbreeding within colonies was negatively correlated with worker body weight and positively correlated with wood consumption. Also, genetic distance between colonies was positively correlated with aggression levels, suggesting a genetic basis to nestmate discrimination cues in this termite population. No obvious trait associated with colony reproductive structure was found that could account for the invasion success of this species.     

Natural Resource Use Strategies in a Forest-Adjacent Ugandan Village

This study documents natural resource use in a forest-adjacent western Ugandan village, and explains how what superficially appears to be a sustainable scenario is in fact quite unstable. Kibwona village is adjacent to Kasokwa Forest, comprised of a small Central Reserve owned by the National Forest Authority (NFA) and several contiguous community forests. Firewood and water collection is legal. However, empirical observations of women’s daily activity budgets and details of resource acquisition show on average, women spent less than 5% of the time collecting natural resources. This is true for resources both in and out of the forest. This may be simply because firewood within household compounds, gardens and woodland–bush areas is abundant, accessible, and closer than the (also close) forest. However, two additional reasons for this behavior may, in fact, hinder long-term sustainability: (1) Many locals also plant eucalyptus trees for firewood, poles, and timber, which, although it is fast growing and makes good firewood, is water-draining and hard on the soils and thus a high cost to subsistence farmers. (2) Fears of harassment by NFA officials when collecting firewood inhibit local people from even entering the forest. Decentralized, collaborative forest management will not happen under oppressive and fear-based relationships, nor can a sustainable firewood supply be based on eucalyptus.     

Extreme microallopatric divergence in a cichlid species from Lake Malawi

We demonstrate significant population structuring on an extremely small spatial scale between adjacent demes of a Lake Malawi haplochromine cichlid species of the mbuna group, Pseudotropheus callainos, separated by only 35 m of habitat discontinuity. This substantiates further the notion that intralacustrine allopatric divergence may help to explain the high level of species richness of the mbuna in comparison to other Malawian cichlids, as well as of the Malawian haplochromines as a whole.     

Aboveground biomass accumulation and tree size distribution in seasonal Atlantic Forest restoration sites

Tropical forests undergoing restoration can present high biomass accumulation rates, especially in the first 20 years. However, native species reforestations often present a bias toward fast growth, low wood density, and small maximum adult size species, contrasting with most mature forest species. Since tree species adult size and wood density are key traits that influence biomass accumulation, these induce uncertainty regarding carbon uptake capabilities of restoration projects in the long term. We compared the density of individuals (DI), basal area (BA), aboveground biomass (AGB), and weighted average wood density (WDW) in 13–14-year-old restoration sites and in mature seasonal Atlantic Forest fragments. We also assessed the contribution of pioneer and non-pioneer and planted and non-planted species on these variables at restoration sites. Furthermore, we investigated the DI and WDW for saplings and seedlings, in order to foresee changes in forest structure that may result from natural recruitment of dense-wood mature species. The BA and WDW at restoration sites were similar to forest fragments, except for large trees (DBH ≥50 cm). Restoration sites recovered AGB to the level of forest fragments only for the smaller size class (DBH 5–19.9 cm). Planted pioneer and non-pioneer species accumulated the greatest AGB (93%), BA (94%), and DI (90%) at restoration sites. The DI of non-planted non-pioneer species with higher WDW increased among saplings and seedlings at restoration sites. The presence of species with a larger adult size and higher WD may indicate long-term increase in biomass accumulation at restoration sites.     

Moral maps and medical imaginaries: clinical tourism at Malawi's College of Medicine

At an understaffed and underresourced urban African training hospital, Malawian medical students learn to be doctors while foreign medical students, visiting Malawi as clinical tourists on short-term electives, learn about “global health.” Scientific ideas circulate fast there; clinical tourists circulate readily from outside to Malawi but not the reverse; medical technologies circulate slowly, erratically, and sometimes not at all. Medicine's uneven globalization is on full display. I extend scholarship on moral imaginations and medical imaginaries to propose that students map these wards variously as places in which—or from which—they seek a better medicine. Clinical tourists, enacting their own moral maps, also become representatives of medicine “out there”: points on the maps of others. Ethnographic data show that for Malawians, clinical tourists are colleagues, foils against whom they construct ideas about a superior and distinctly Malawian medicine and visions of possible alternative futures for themselves.     

Detection and stability of quantitative trait loci (QTL) in Eucalyptus globulus

Eucalyptus globulus Labill. ssp. globulus is an important tree species for the pulp and paper industry, and several breeding programmes throughout the world are striving to improve key traits such as growth and wood density. This study aimed to detect quantitative trait loci (QTL) for growth, wood density, relative bark thickness and early flowering in a single full-sib E. globulus family grown across seven sites. Growth was measured a number of times over a 6-year period, enabling temporal stability of growth QTL to be studied. Ten putative QTL (LOD > 2.0) were detected in the single family, which was of moderate size. Based on permutations of the trait data, six of these QTL were significant at the experimentwise significance level of 0.1 for at least one of the four models implemented in analysis to remove site effects. For wood density, two putative QTL explained 20% of the variance for the trait, indicating that a small number of QTL might explain a reasonable proportion of the trait variance. One of these QTL was found to be independent of QTL for growth whereas the second QTL co-segregated with a QTL for relative incremental growth. The marker nearest to this QTL was associated with fast growth but low wood density. A putative growth QTL at year 6 was found to be relatively stable across ages. In addition, it was found that residuals from models based on measurements from across all families across all sites in the trial detected QTL with greater experimentwise significance.     

Antibody to P. falciparum in pregnancy varies with intermittent preventive treatment regime and bed net use

BACKGROUND: Antibodies towards placental-binding P. falciparum are thought to protect against pregnancy malaria; however, environmental factors may affect antibody development. Methods and Findings: Using plasma from pregnant Malawian women, we measured IgG against placental-binding P. falciparum parasites by flow cytometry, and related results to intermittent preventive treatment (IPTp) regime, and bed net use. Bed net use was associated with decreased antibody levels at mid-pregnancy but not at 1 month post partum (1 mpp). At 1 mpp a more intensive IPTp regime was associated with decreased antibody levels in primigravidae, but not multigravidae. CONCLUSIONS/SIGNIFICANCE: Results suggest bed nets and IPTp regime influence acquisition of pregnancy-specific P. falciparum immunity.     

Constraints and Opportunities for Sustainable Livelihoods and Cash Income Generation from NTFPs in the Mountains of Northern Parts of Pakistan

Pakistan′s forest resource base is mostly found in the mountains of the North-West Frontier Province (NWFP) supporting the livelihood of the rural poor and providing different ecological services. The present study was, therefore, initiated with the aim to evaluate different constraints and opportunities for sustainable livelihoods and cash income generation from NTFPs in the mountainous area of NWFP, Pakistan during 2008. Information was collected through questionnaire and interviews during field trips. A total of 117 NTFPs species have been recorded which are being used locally for various purposes such as fuel wood, fodder, medicinal plants, vegetables, mushroom, agricultural tools making, furniture, thatching, shade, fencing/ poles, ornamental purpose and animal products. The majority of plants are multi-functional like Pinus wallichiana provides timber, firewood, torch wood, the leaves/small branches are used as thatch for roofing, split logs are used for fencing and the decomposed needles are collected as humus for agricultural fields. These products were widely used by the indigenous community supporting their livelihood. The study proposes protection and sustainable management of these valuable resources for rural livelihoods, which might be useful for developing regional strategies of sustainable management of forest resources.     

The consumption of wood by rural households in Gokwe Communal Area,Zimbabwe

The objectives of this paper are to quantify the annual household consumption of wood for different purposes and to investigate the types of wood used for each purpose. Households in part of Gokwe Communal Area, a rural Zimbabwean study area in which wood is considered plentiful, use a mean 4.8 tons per household per year (t hh ^–1 yr ^–1 ) of wood for fuel, comprising 4.0 t to meet day-to-day requirements and 0.8 t for special occasions and beer brewing. In addition, building and repairing wooden structures require 3.5 t hh ^–1 yr ^–1 The total annual consumption is at most 8.3 t hh ^–1 yr ^–1 depending on the amount of wood in wooden structures that is recycled into new structures or as firewood. Wide variation around the mean annual consumption is expected because of differences among households and errors associated with calculation. The different purposes to which wood is put require wood of different types. Firewood for day-to-day use consists of small dead pieces collected in headloads. For brewing and special occasions large logs are used. Poles and small branches are freshly cut for wooden structures, with poles of particular girths and lengths being used for different components of the structures. Species is also taken into account in the collection of wood for fuel and construction. Disaggregation of the yearly consumption by site and species is important to the assessment of supply and demand of wood.     

Potentially Modifiable Factors Associated with Death of Infants and Children with Severe Pneumonia Routinely Managed in District Hospitals in Malawi

Objective

To investigate recognised co-morbidities and clinical management associated with inpatient pneumonia mortality in Malawian district hospitals.

Methods

Prospective cohort study, of patient records, carried out in Malawi between 1^st October 2000 and 30^th June 2003. The study included all children aged 0-59 months admitted to the paediatric wards in sixteen district hospitals throughout Malawi with severe and very severe pneumonia. We compared individual factors between those that survived (n = 14 076) and those that died (n = 1 633).

Results

From logistic regression analysis, predictors of death in hospital, adjusted for age, sex and severity grade included comorbid conditions of meningitis (OR =2.49, 95% CI 1.50-4.15), malnutrition (OR =2.37, 95% CI 1.94-2.88) and severe anaemia (OR =1.41, 95% CI 1.03-1.92). Requiring supplementary oxygen (OR =2.16, 95% CI 1.85-2.51) and intravenous fluids (OR =3.02, 95% CI 2.13-4.28) were associated with death while blood transfusion was no longer significant (OR =1.10, 95% CI 0.77-1.57) when the model included severe anaemia.

Conclusions

This study identified a number of challenges to improve outcome for Malawian infants and children hospitalised with pneumonia. These included improved assessment of co-morbidities and more rigorous application of standard case management.     

Children and Wild Foods in the Context of Deforestation in Rural Malawi

There is growing recognition of the contribution of wild foods to local diets, nutrition, and culture. Yet disaggregation of understanding of wild food use by gender and age is limited. We used a mixed methods approach to determine the types, frequencies, and perceptions of wild foods used and sold by children in four villages in southern Malawi that have different levels of deforestation. Household and individual dietary diversity scores are low at all sites. All households consume one or more wild foods. Across the four sites, children listed 119 wild foods, with a wider variety at the least deforested sites than the most deforested ones. Older children can name more wild foods than younger ones. More children from poor households sell wild foods than from well-off households. Several reasons were provided for the consumption or avoidance of wild foods (most commonly taste, contribution to health, limited alternatives, hunger, availability, local taboos).     

The relationship between wood density and mortality in a global tropical forest data set

Wood density is thought to be an important indicator of plant life history because it is coupled to many aspects of whole-plant form and function. We used a hierarchical Bayesian approach to explain variation in mortality rates with wood density, drawing on data for 765,500 trees from 1639 species at 10 sites located across the Old and New World tropics. Mortality rates declined with increasing wood density at five of 10 sites. Similar negative trends were detected at four additional sites, while one site showed no relationship. Our model explained 40% of variation in mortality on average. Both wood density and mortality rates show a high degree of phylogenetic conservatism. Grouping species by family across sites in a second analysis, we found considerable variation in the relationship between wood density and mortality, with 10 of 27 families demonstrating a strong negative relationship. Our results highlight the importance of wood density as a functional trait in tropical forests, as it is strongly linked to variation in survival. However, the relationship varied among families, plots, and even census intervals within sites, indicating that the factors responsible for the relationship between wood density and mortality vary spatially, taxonomically and temporally.     

Tree allometry and improved estimation of carbon stocks and balance in tropical forests

Tropical forests hold large stores of carbon, yet uncertainty remains regarding their quantitative contribution to the global carbon cycle. One approach to quantifying carbon biomass stores consists in inferring changes from long-term forest inventory plots. Regression models are used to convert inventory data into an estimate of aboveground biomass (AGB). We provide a critical reassessment of the quality and the robustness of these models across tropical forest types, using a large dataset of 2,410 trees ≥ 5 cm diameter, directly harvested in 27 study sites across the tropics. Proportional relationships between aboveground biomass and the product of wood density, trunk cross-sectional area, and total height are constructed. We also develop a regression model involving wood density and stem diameter only. Our models were tested for secondary and old-growth forests, for dry, moist and wet forests, for lowland and montane forests, and for mangrove forests. The most important predictors of AGB of a tree were, in decreasing order of importance, its trunk diameter, wood specific gravity, total height, and forest type (dry, moist, or wet). Overestimates prevailed, giving a bias of 0.5–6.5% when errors were averaged across all stands. Our regression models can be used reliably to predict aboveground tree biomass across a broad range of tropical forests. Because they are based on an unprecedented dataset, these models should improve the quality of tropical biomass estimates, and bring consensus about the contribution of the tropical forest biome and tropical deforestation to the global carbon cycle. Electronic Supplementary Material Supplementary material is available for this article at     

Validation of a Dutch risk score predicting poor outcome in adults with bacterial meningitis in Vietnam and Malawi

We have previously developed and validated a prognostic model to predict the risk for unfavorable outcome in Dutch adults with bacterial meningitis. The aim of the current study was to validate this model in adults with bacterial meningitis from two developing countries, Vietnam and Malawi. Demographic and clinical characteristics of Vietnamese (n = 426), Malawian patients (n = 465) differed substantially from those of Dutch patients (n = 696). The Dutch model underestimated the risk of poor outcome in both Malawi and Vietnam. The discrimination of the original model (c-statistic [c] 0.84; 95% confidence interval 0.81 to 0.86) fell considerably when re-estimated in the Vietnam cohort (c = 0.70) or in the Malawian cohort (c = 0.68). Our validation study shows that new prognostic models have to be developed for these countries in a sufficiently large series of unselected patients.