Search Results (50)

Rural areas around the world are increasingly dealing with energy and environmental challenges. These challenges are particularly acute in developing countries, where persistent reliance on traditional energy sources—such as wood fuel—intersects with concerns about forest conservation and energy sustainability. While wood fuel use is often portrayed as unsustainable, it is important to acknowledge that much of it remains ecologically viable and socially embedded. This study explores the role of rural entrepreneurs in shaping low-carbon transitions at the intersection of household energy practices and environmental stewardship. Fieldwork was carried out in four rural Zambian communities in 2016 and complemented by 2024 follow-up reports. It examines the connections between household energy choices, greenhouse gas emissions, and forest resource dynamics. Findings reveal that over 60% of rural households rely on charcoal for cooking, with associated emissions estimated between 80 and 150 kg CO₂ per household per month. Although this is significantly lower than the average per capita carbon footprint in industrialized countries, such emissions are primarily biogenic in nature. While rural communities contribute minimally to global climate change, their practices have significant local environmental consequences. This study draws attention to the structural constraints as well as emerging opportunities within Zambia’s rural energy economy. It positions rural entrepreneurs not merely as policy recipients but as active agents of innovation, environmental monitoring, and participatory resource governance. A model is proposed to support sustainable rural energy transitions by aligning forest management with context-sensitive emissions strategies. Full article

The overexploitation of forest resources in the Lubumbashi Charcoal Production Basin in the southeastern Democratic Republic of the Congo (DR Congo) leads to deforestation and miombo woodlands degradation, threatening local livelihoods. Current forestry policies are ineffective, partly due to neglecting traditional ecological knowledge (TEK). This study identifies and describes TEK and practices related to biodiversity conservation and sustainable miombo woodlands management. Focus groups and interviews were conducted in four villages (Maksem, Mwawa, Nsela, and Texas), selected based on forest resource availability and population size. Data on sacred sites, conservation practices, knowledge transmission, ceremonies, and socio-demographic factors were analyzed using descriptive statistics, Fisher’s exact test, and Jaccard’s similarity index. The findings revealed that 75% of respondents identified sacred sites where logging activities are strictly prohibited. Thirty sacred tree species were identified, with stronger compliance in villages with a high availability of forest resources. This TEK is predominantly transmitted orally through family councils, as well as traditional ceremonies or rituals. Conservation practices include small-scale farming, intercropping, avoiding tree cutting in sacred sites, and using deadwood. However, only farming and intercropping are still commonly practiced, particularly in resource-scarce villages (64%). Women and elders are primary custodians of TEK, though its application is constrained by population growth and dwindling forest resources. The findings emphasize the crucial role of TEK in strengthening forest restoration initiatives by selecting key woody species and sustainable practices, while fostering community involvement. As such, decision makers should prioritize integrating TEK into DR Congo’s forest policies to support biodiversity conservation and miombo woodlands restoration efforts. Full article

The sustainability of reforestation initiatives depends on the involvement of local communities, whose lack of ownership compromises efforts to combat deforestation in the Lubumbashi Charcoal Production Basin. This study assesses reforestation activities in two village areas (Milando and Mwawa), based on individual interviews (50 individuals/village area) and floristic inventories carried out in two types of habitats (reforested and unexploited) for each village area. The hypotheses tested were the following: (i) Reforested habitats and tree species were selected collaboratively, ensuring an inclusive approach; (ii) ecological parameters—density per hectare, quadratic mean diameter, basal area, and floristic diversity—of reforested sites were comparable to those of unexploited miombo due to protection allowing natural recovery; and (iii) ethnobotanical and floristic patterns reflect varying levels of anthropogenic disturbance and the limited diversity of species used in reforestation. Thus, the interviews gathered data on habitat and woody species selection for reforestation and management practices, while the inventories assessed the condition of these reforested habitats in terms of density per hectare, basal area, quadratic mean diameter, and floristic diversity. The results show that in both village areas, the selection of habitats for reforestation was carried out concertedly (22.00–44.00% of citations). Woody species were chosen according to the needs of local communities (40–52%) and the availability of seeds (18.00–44.00%). Furthermore, management practices for these reforested habitats include planning/assessment meetings (26.00–38.00%) and maintenance activities, such as firebreaks (38.00–46.00%) and surveillance of reforested habitats (24.00%). Additionally, these practices are being increasingly neglected, jeopardizing reforestation efforts. However, density/ha, basal area, quadratic mean diameter, and floristic diversity did not show significant differences between reforested and unexploited habitats, particularly at Milando (p > 0.05). Furthermore, floristic similarity is 55.56% for reforested habitats and 93.75% for unexploited habitats but remains low between reforested and unexploited habitats (40.00–47.62%). This similarity between ethnobotanical and floristic lists is also low (43.75–31.58%). Finally, a total of 442 woody individuals were recorded in reforested habitats and 630 in unexploited ones, with Fabaceae dominating both habitat types. Despite some cited reforestation species like Acacia polyacantha being absent, Brachystegia spiciformis emerged as the most prevalent species in both reforested and unexploited areas. The results of the present study suggest a sustainable and continuous management of these reforested habitats for an effective reconstitution of the forest cover. To reinforce the sustainable management of these reforested habitats, it is recommended that decision-makers conduct awareness-raising campaigns and establish payment for environmental service mechanisms to motivate communities. Full article

The wattle tree (Acacia mearnsii) is gaining importance as an exotic species in northwestern Ethiopia, providing ecological, environmental, and economic benefits, especially for fuelwood and charcoal production. This study aimed to investigate the effect of tree spacing on the growth and biomass of wattle trees. The study employed a randomized complete block design with three replications across three spacing treatments (0.5 m × 0.5 m, 1 m × 1 m, and 1.5 m × 1.5 m) in the Fagita district. Tree height and diameter measurements were taken at 12, 18, and 30 months post-planting from stands established in 2021. The results showed significant differences in tree height among the spacing treatments at 18 and 30 months. The closest spacing (0.5 m × 0.5 m) yielded the highest average tree heights of 32.12 cm, 84.86 cm, and 302.98 cm at 12, 18, and 30 months, respectively. At 18 months, the largest average diameter (1.22 cm) was found in the narrowest spacing (0.5 m × 0.5 m), whereas at 30 months, the widest spacing (1.5 m × 1.5 m) recorded the largest diameter (1.51 cm). Throughout the study, height, diameter, and average aboveground biomass exhibited an inverse relationship with spacing, with this effect diminishing as trees aged. Tree spacing significantly impacted average aboveground biomass at 18 months, with the densest spacing (0.5 m × 0.5 m) yielding the highest average aboveground biomass (1.97 kg at 18 months and 2.41 kg at 30 months). Average aboveground biomass increased as the trees matured. These findings suggest that closer spacing of A. mearnsii can enhance biomass production, positioning it as a promising candidate for energy generation. Leveraging these insights can optimize resource utilization while supporting global energy demands and reforestation initiatives aimed at carbon sequestration. Full article

Pinus albicaulis (whitebark pine) is a keystone species, providing food and habitat to wildlife, in high-elevation ecological communities. In recent years, this important species has been negatively impacted by changes in fire regimes, increased Dendroctonus ponderosae (mountain pine beetle) outbreaks associated with human landscape and climate modification, and the continued impact of the non-native Cronartium ribicola (white pine blister rust). This research investigates changes in fire occurrence, the establishment of Pinus albicaulis, and fuel availability at a high-elevation site in the Sawtooth National Recreation Area, Idaho, USA. Charcoal and pollen analyses were used to reconstruct fire and vegetation patterns for Phyllis Lake, Idaho, USA, over the past ~8200 cal y BP. We found that significant fire episodes occurred when the pollen accumulation rates (PARs) indicated more arboreal fuel availability, and we identified that Pinus albicaulis became well established at the site ~7200 cal y BP. The high-elevation nature of Phyllis Lake (2800 m) makes this record unique, as there are not many paleorecords at this high elevation from the Northern Rocky Mountains, USA. Additional high-elevation sites in Pinus albicaulis habitats will provide critical insight into the long-term dynamics of this threatened species. Full article

Seedling establishment is often a critical bottleneck in the revegetation of mine tailings and similar substrates. Biochar and deactivated yeast are potential sustainable materials that could be used in this context as seed coatings to aid in seedling establishment. We conducted a greenhouse study on biochar and deactivated yeast use as seed coatings, assessing germination, establishment, and early growth of white clover (Trifolium repens) and purple prairie clover (Dalea purpurea). Coated seeds were applied to a mine tailing, a coarse granitic sand, and potting soil mix substrates; seedling establishment and growth were monitored over 75 days. Biochar coatings enhanced the seedling establishment of Trifolium, with biochar and biochar plus yeast coatings giving the best results. In some cases, these effects persisted throughout the experiment: biochar coatings resulted in a ~fivefold increase in Trifolium biomass at harvest for plants in the potting soil mix but had neutral effects on sand or tailings. Biochar seed coatings also enhanced Dalea germination in some cases, but the benefits did not persist. Our results indicate that biochar-based seed coatings can have lasting effects on plant growth well beyond germination but also emphasize highly species-specific responses that highlight the need for further study. Full article

Podophyllum hexandrum Royle, also known as Podophyllum emodi Wall, holds significant ecological, ornamental, and medicinal values. However, it has become endangered due to overexploitation, prolonged seed dormancy, slow natural regeneration, and climate change. This study developed an efficient in vitro protocol for callogenesis and micropropagation of P. hexandrum to conserve germplasm in in vitro conditions. Callus formation from various plant parts, including the leaf, stem, rhizome, radicle, and cotyledon, was induced using Murashige and Skoog (MS) medium supplemented with different plant growth regulators. The combination of benzyladenine at 1 mg L⁻¹ and 4-dichlorophenoxy acetic acid at 3 mg L⁻¹ was optimal for biomass production, yielding 215.88 ± 0.31 mg, with growth per gram at 8.32 ± 0.32 and a growth rate of 13.62 ± 0.25 mg/day on MS medium. For shoot proliferation, benzyladenine (3.5 mg L⁻¹) and naphthalene acetic acid (0.5 mg L⁻¹) combined with activated charcoal showed the highest shoot induction percentage per explant. For shoot regeneration from calluses, 6-benzylaminopurine (0.5 mg L⁻¹) and thidiazuron (2 mg L⁻¹) were most effective, producing superior shoot length, number of regenerations, and regeneration percentage. Root induction was successful with α-naphthalene acetic acid supplementation (0.5 to 1.5 mg L⁻¹) in MS medium, resulting in the highest number per explant (4.08 ± 0.08), length (5.45 ± 0.15 cm), and rooting rate (87.00 ± 1.66%) of roots in plantlets. Subculturing for callus culture was performed every 28 days for up to four subcultures to prevent nutrient depletion and toxic metabolite accumulation, ensuring tissue health and viability. Continuous subculturing of callus on MS medium maintained healthy P. hexandrum germplasm in vitro. Overall, this micropropagation protocol provides a rapid system for conserving P. hexandrum germplasm. Full article

Elephant grass (EG), or Pennisetum purpureum, is gaining attention as a robust renewable biomass source for energy production amidst growing global energy demands and the push for alternatives to fossil fuels. This review paper explores the status of EG as a sustainable bioenergy resource, integrating various studies to present a comprehensive analysis of its potential in renewable energy markets. Methods employed include assessing the efficiency and yield of biomass conversion methods such as pretreatment for bioethanol production, biomethane yields, direct combustion, and pyrolysis. The analysis also encompasses a technoeconomic evaluation of the economic viability and scalability of using EG for energy production, along with an examination of its environmental impacts, focusing on its water and carbon footprint. Results demonstrate that EG has considerable potential for sustainable energy practices due to its high biomass production and ecological benefits such as carbon sequestration. Despite challenges in cost competitiveness with traditional energy sources, specific applications like small-scale combined heat and power (CHP) systems and charcoal production show economic promise. Conclusively, EG presents a viable option for biomass energy, potentially playing a pivotal role in the biomass sector as the energy landscape shifts towards more sustainable solutions; although, technological and economic barriers need further addressing. Full article

Edible fungi are a valuable resource in the search for sustainable solutions to environmental pollution. Their ability to degrade organic pollutants, extract heavy metals, and restore ecological balance has a huge potential for bioremediation. They are also sustainable food resources. Edible fungi (basidiomycetes or fungi from other divisions) represent an underutilized resource in the field of bioremediation. By maximizing their unique capabilities, it is possible to develop innovative approaches for addressing environmental contamination. The aim of the present study was to find selective chemical agents suppressing the growth of microfungi and bacteria, but not suppressing white-rot fungi, in order to perform large-scale cultivation of white-rot fungi in natural unsterile substrates and use it for different purposes. One application could be the preparation of a matrix composed of wooden sleeper (contaminated with PAHs) and soil for further hazardous waste bioremediation using white-rot fungi. In vitro microbiological methods were applied, such as, firstly, compatibility tests between bacteria and white-rot fungi or microfungi, allowing us to evaluate the interaction between different organisms, and secondly, the addition of chemicals on the surface of a Petri dish with a test strain of microorganisms of white-rot fungi, allowing us to determine the impact of chemicals on the growth of organisms. This study shows that white-rot fungi are not compatible to grow with several rhizobacteria or bacteria isolated from soil and bioremediated waste. Therefore, the impact of several inorganic materials, such as lime (hydrated form), charcoal, dolomite powder, ash, gypsum, phosphogypsum, hydrogen peroxide, potassium permanganate, and sodium hydroxide, was evaluated on the growth of microfungi (sixteen strains), white-rot fungi (three strains), and bacteria (nine strains) in vitro. Charcoal, dolomite powder, gypsum, and phosphogypsum did not suppress the growth either of microfungi or of bacteria in the tested substrate, and even acted as promoters of their growth. The effects of the other agents tested were strain dependent. Potassium permanganate could be used for bacteria and Candida spp. growth suppression, but not for other microfungi. Lime showed promising results by suppressing the growth of microfungi and bacteria, but it also suppressed the growth of white-rot fungi. Hydrogen peroxide showed strong suppression of microfungi, and even had a bactericidal effect on some bacteria, but did not have an impact on white-rot fungi. The study highlights the practical utility of using hydrogen peroxide up to 3% as an effective biota-suppressing chemical agent prior to inoculating white-rot fungi in the large-scale bioremediation of polluted substrates, or in the large-scale cultivation for mushroom production as a foodstuff. Full article

Mangroves rehabilitated after deforestation by commercial exploitation must be monitored to confirm that key ecosystem functions are being restored. Brachyuran crabs are conspicuous mangrove macrofauna and were selected as potential indicators of ecosystem recovery. A deforested former mangrove charcoal concession area in Ranong was rehabilitated by planting Rhizophora (1994), Bruguiera and Ceriops (1995) seedlings in single-species blocks. A second area, deforested and heavily degraded by tin mining, was rehabilitated with R. mucronata in 1985. Crabs at these sites were compared with those in a mixed-species conservation forest. Timed collections were made in 1999, 2008 and 2019 to compare crab diversity and relative abundance between sites and years. Thirty-three brachyuran crab species were recorded. Fiddler crabs (Austruca triangularis, Tubuca rosea) and the signal crab, Metaplax elegans, were most abundant, followed by sesarmid crabs (15 species). Species composition differed significantly between sites but not between the four planted tree species blocks. We propose Metaplax elegans as an indicator of ecological development in low-lying/newly formed sediments; fiddler crabs as equivalent indicators in young mangrove plantations/open forest habitats; and a diverse sesarmid community to indicate ecological functioning in older plantations/dense forests. Full article

Near-surface O₃ has negative effects on plant productivity; however there were few studies on the effects of O₃ pollution on the belowground part of the ecosystem. The effect of O₃ stress on the belowground parts of poplar is unclear. We investigated the effects of O₃ pollution on poplar rhizosphere soil in open-top chambers (OTC). Two kinds of plants with different O₃ sensitivity were selected, i.e., high-sensitive poplar clone 546 and low-sensitive poplar clone 107. The control group and high-concentration O₃ group were set up: charcoal-filtered air, CF; unfiltered air + 60 ppb O₃, NF. Poplar rhizosphere soil was taken after 96 days (15 June to 17 September 2020) of cultivation in OTCs. O₃ stress decreased the amplicon sequence variations (ASVs) of microorganisms in poplar 107 and poplar 546 rhizosphere soil, with no significant interspecific difference. The effect of O₃ fumigation on the fungal community was greater than that on the bacterial community. The correlation between the bacterial community and rhizosphere soil physicochemical indices was closer than that of the fungal community. Some fungi, such as Clitopilus hobsonii, Mortierella sp., and Minimedusa, might help poplar resist the O₃ stress. O₃ stress had direct impacts on the pH, nutrients, and enzyme activities of rhizosphere soil, while it had indirect negative impacts on microbial community composition by nutrients. There was no difference in sensitivity between rhizosphere soil response to O₃ stress of poplar clone 107 and clone 546, which might take a longer accumulation time to show the effect. This study provides a certain basis for accurately evaluating the ecological effects of O₃ pollution. Full article

Population growth in the city of Lubumbashi in the southeastern Democratic Republic of the Congo (DR Congo) is leading to increased energy needs, endangering the balance of the miombo woodland in the rural area referred to as the Lubumbashi charcoal production basin (LCPB). In this study, we quantified the deforestation of the miombo woodland in the LCPB via remote sensing and landscape ecology analysis tools. Thus, the analysis of Landsat images from 1990, 1998, 2008, 2015 and 2022 was supported by the random forest classifier. The results showed that the LCPB lost more than half of its miombo woodland cover between 1990 (77.90%) and 2022 (39.92%) and was converted mainly to wooded savannah (21.68%), grassland (37.26%), agriculture (2.03%) and built-up and bare soil (0.19). Consecutively, grassland became the new dominant land cover in 2022 (40%). Therefore, the deforestation rate (−1.51%) is almost six-times higher than the national average (−0.26%). However, persistent miombo woodland is characterised by a reduction, over time, in its largest patch area and the complexity of its shape. Consequently, because of anthropogenic activities, the dynamics of the landscape pattern are mainly characterised by the attrition of the miombo woodland and the creation of wooded savannah, grassland, agriculture and built-up and bare soil. Thus, it is urgent to develop a forest management plan and find alternatives to energy sources and the sedentarisation of agriculture by supporting local producers to reverse these dynamics. Full article

Mangroves in Zanzibar have a high value for biodiversity and scenic beauty. However, mangroves are susceptible to anthropogenic and natural environmental disturbances. Although global mangrove monitoring systems exist, it is the practitioners focused on small mangrove areas who are knowledgeable about the area in which they work. This study examined the change in mangrove cover in Chwaka Bay and Menai Bay, between 1973 and 2020, using Landsat satellite data. The transformed divergence (TD) index and Jeffries–Matusita (J-M) distance were used to calculate separability of land cover classes before classification. The overall accuracies ranged between 82.5 and 92.7% for Chwaka Bay and 85.5 and 94.5% for Menai Bay. The kappa coefficients (ĸ) were in the range of 0.72–0.90, while the producer’s and user’s accuracies were between 72 and 100%. Chwaka Bay’s annual decrease in mangrove cover between 1973 and 2020 was 48.5 ha, compared to Menai’s 6.8 ha. The loss of mangroves in Zanzibar is linked to illegal timber/pole cutting, firewood collection, charcoal burning, unsustainable aquaculture, and agricultural and urban development. Others are changes in environmental conditions that are suitable for mangroves and climate change. This study is crucial in providing a basis for the ecological restoration and management of Zanzibar’s mangrove ecosystem. Full article

Ethnographic observations suggest that Indigenous peoples employed a distinct regime of frequent, low-intensity fires in the Australian landscape in the past. However, the timing of this behaviour and its ecological impact remain uncertain. Here, we present detailed analysis of charcoal, including a novel measure of fire severity using Fourier transform infrared (FTIR) spectroscopy, at a site in eastern Australia that spans the last two glacial/interglacial transitions between 135–104 ka and 18–0.5 ka BP (broadly equivalent to Marine Isotope Stage (MIS) 6-5 and 2-1, respectively). The accumulation of charcoal and vegetation composition was similar across both periods, correlating closely with Antarctic ice core records, and suggesting that climate is the main driver of fire regimes. Fire severity was lower over the past 18,000 years compared to the penultimate glacial/interglacial period and suggests increasing anthropogenic influence over the landscape during this time. Together with local archaeological records, our data therefore imply that Indigenous peoples have been undertaking cultural burning since the beginning of the Holocene, and potentially the end of the Last Glacial Maximum. We highlight the fact that this signal is not easily discernible in the other proxies examined, including widely used charcoal techniques, and propose that any anthropogenic signal will be subtle in the palaeo-environmental record. While early Indigenous people’s reasons for landscape burning were different from those today, our findings nonetheless suggest that the current land management directions are based on a substantive history and could result in a reduction in extreme fire events. Full article

Eucalyptus species have been widely employed in the projects of reforestation in Tunisia. Although their ecological functions are controversial, these plants are indeed important to counteract soil erosion, and represent a fast-growing source of fuelwood and charcoal wood. In the present study, we considered five Eucalyptus species, namely Eucalyptus alba, E. eugenioides, E. fasciculosa, E. robusta, and E. stoatei cultivated in the Tunisian Arboreta. The aim was to carry out the micromorphological and anatomical characterization of the leaves, the extraction and phytochemical profile of the essential oils (EOs), and the evaluation of their biological properties. Four of the EOs showed the prevalence of eucalyptol (1,8-cineole) varying from 64.4 to 95.9%, whereas a-pinene predominated in E. alba EO (54.1%). These EOs showed in vitro antioxidant activity, and reduced the oxidative cellular stress as shown by their activity on reactive oxygen species (ROS) production, and modulation of the expression of antioxidant enzymes, such as glutamate-cysteine ligase (GCL) and heme oxygenase-1 (Hmox-1). Moreover, the EOs inhibited the production of nitric oxide (NO), showing anti-inflammatory activity. The data collected suggest that these EOs may be considered a promising therapeutic strategy for inflammation-based diseases and may represent an additional value for the economy of Tunisia. Full article