A majority of people in developing countries use biomass energy for cooking and heating due to its affordability, accessibility and convenience. However, unsustainable biomass use leads to forest degradation and climate change. Therefore, this study was carried out in Kwale County, Kenya, on the use of a biochar-producing gasifier cook stove and implications of its uptake on livelihoods and the environment. Fifty households were trained and issued with a gasifier for free. After 2–3 months of gasifier use, a survey was conducted to investigate the implications of its uptake. The direct impacts included reduced fuel consumption by 38%, reduced time spent in firewood collection, reduced expenditure on cooking fuel, diversification of cooking fuels, improved kitchen conditions and reduced time spent on cooking. The potential benefits included income generation, increased food production, reduced impacts on environment and climate change and reduced health problems. Improved biomass cook stoves can alleviate problems with current cooking methods, which include inefficient fuel use, health issues caused by smoke, and environmental problems. These benefits could contribute to development through alleviating poverty and hunger, promoting gender equality, enhancing good health and sustainable ecosystems and mitigating climate change. The study recommends the promotion of cleaner cooking stoves, particularly gasifiers, among households in rural areas while paying attention to user needs and preferences.
Tag: gas emissions
Earthworms regulate ability of biochar to mitigate CO2 and N2O emissions from a tropical soil
Soils account for >80% and 20% of the total agricultural N2O and CO2 emissions respectively. Soil management activities that target improved soil health, such as enhancing earthworm activity, may also stimulate further emissions of CO2 and N2O. One recommended strategy for mitigating these soil emissions is biochar amendment. However greater clarity on the interaction between earthworm activity and biochar, and subsequent impact on CO2 and N2O are needed to evaluate the environmental impacts of management practice. We measured N2O and CO2 emissions from a kaolinitic Acrisol in the presence or absence of earthworms, with and without application of two different biochars in a microcosm study. The two biochars were derived from indigenous trees; Zanthoxylum gilletii and Croton megalocarpus, and were tested at three application rates of 5 Mg ha−1, 10 Mg ha−1 and 25 Mg ha−1. Emissions of CO2 and N2O increased by 26% and 72% respectively in the presence of earthworms. In microcosms with biochar and earthworms however, emissions depended on type of biochar and rate of application. With C. megalocarpus, CO2 emission increased with increasing rates of biochar application with 25 Mg ha−1 resulting in higher CO2 fluxes compared to no-biochar control (p = 0.002), while no change was observed with Z. gilletii at the same rate. Nitrous oxide emissions were suppressed at 25 Mg ha−1 for both C. megalocarpus (p = 0.009) and Z. gilletii (p = 0.011). Reduction in N2O flux was however not consistent across biochar types. No change in N2O was observed with 5 Mg ha−1 and 10 Mg ha−1of C. megalocarpus. Biochar from Z. gilletii at 5 Mg ha−1 however led to increase in N2O emissions (p < 0.001). Our findings suggest that earthworms may moderate the effect of biochar, with suppression of N2O emissions occurring at only high biochar application rates, which may occur at the cost of increasing CO2 emissions. These findings contrast with biochar suppressing effect on N2O emissions even at moderate biochar rates of (10 Mg ha−1) when in absence of earthworms, an outcome typical of many laboratory experiments. These findings highlight new interactions among application rate, source of biochar (and hence properties) and earthworms.
Bioenergy sustainability in the global South: Constraints and opportunities
Many countries have recently adopted bioenergy as part of a critical strategy to reduce greenhouse gas (GHG) emissions to meet targets under the Paris Climate Agreement. Because of increased efficiency and lower production costs, along with legislative support and investment incentives, bioenergy use is swiftly becoming a renewable energy substitute for fossil fuels. The study provides a better understanding of bioenergy issues, potential and sustainability to inform countries in the global South and provide guidance on integrating bioenergy into their national energy plans by proposing a simplified sustainability framework for wood-based bioenergy.
Arguments are reviewed against biomass energy expansion, mainly developed in the context of the global north. The benefits of biomass energy expansion are also reviewed with a focus on conditions common to the global south. A sustainability framework is presented to illustrate better use of low-value land resources, produce bioenergy, restore ecosystem services, and mitigate and adapt to climate change. The study recommends guidance to establish sustainable, wood-based bioenergy supply in developing countries in the global South, which help ensure that biomass supply chains adhere to the principles and criteria of bioenergy sustainability.
Rewetting Tropical Peatlands Reduced Net Greenhouse Gas Emissions in Riau Province, Indonesia
Draining deforested tropical peat swamp forests (PSFs) converts greenhouse gas (GHG) sinks to sources and increases the likelihood of fire hazards. Rewetting deforested and drained PSFs before revegetation is expected to reverse this outcome. This study aims to quantify the GHG emissions of deforested PSFs that have been (a) reforested, (b) converted into oil palm, or (c) replanted with rubber. Before rewetting, heterotrophic soil respiration in reforested, oil palm, and rubber plantation areas were 48.91 ± 4.75 Mg CO2 ha−1 yr−1, 54.98 ± 1.53 Mg CO2 ha−1 yr−1, and 67.67 ± 2.13 Mg CO2 ha−1 yr−1, respectively. After rewetting, this decreased substantially by 21%, 36%, and 39%. Conversely, rewetting drained landscapes that used to be methane (CH4) sinks converted them into CH4 sources; almost twice as much methane was emitted after rewetting. Nitrous oxide (N2O) emissions tended to decrease; in nitrogen-rich rubber plantations, N2O emissions halved; in nitrogen-poor reforested areas, emissions reduced by up to a quarter after rewetting. Overall, rewetting reduced the net emissions up to 15.41 Mg CO2-eq ha−1 yr−1 (25%) in reforested, 18.36 Mg CO2-eq ha−1 yr−1 (18%) in oil palm, and 28.87 Mg CO2-eq ha−1 yr−1 (17%) in rubber plantation areas.
Carbon Dynamics in Rewetted Tropical Peat Swamp Forests
Degraded and drained peat swamp forests (PSFs) are major sources of carbon emissions in the forestry sector. Rewetting interventions aim to reduce carbon loss and to enhance the carbon stock. However, studies of rewetting interventions in tropical PSFs are still limited. This study examined the effect of rewetting interventions on carbon dynamics at a rewetted site and an undrained site. We measured aboveground carbon (AGC), belowground carbon (BGC), litterfall, heterotrophic components of soil respiration (Rh), methane emissions (CH4), and dissolved organic carbon (DOC) concentration at both sites. We found that the total carbon stock at the rewetted site was slightly lower than at the undrained site (1886.73 ± 87.69 and 2106.23 ± 214.33 Mg C ha−1, respectively). The soil organic carbon (SOC) was 1685 ± 61 Mg C ha−1 and 1912 ± 190 Mg C ha−1 at the rewetted and undrained sites, respectively, and the carbon from litterfall was 4.68 ± 0.30 and 3.92 ± 0.34 Mg C ha−1 year−1, respectively. The annual average Rh was 4.06 ± 0.02 Mg C ha−1 year−1 at the rewetted site and was 3.96 ± 0.16 Mg C ha−1 year−1 at the undrained site. In contrast, the annual average CH4 emissions were −0.0015 ± 0.00 Mg C ha−1 year−1 at the rewetted site and 0.056 ± 0.000 Mg C ha−1 year−1 at the undrained site. In the rewetted condition, carbon from litter may become stable over a longer period. Consequently, carbon loss and gain mainly depend on the magnitude of peat decomposition (Rh) and CH4 emissions.
Pathways toward inclusive low-emission dairy development in Tanzania: Producer heterogeneity and implications for intervention design
Reducing greenhouse gas (GHG) emissions from the agriculture sector – especially livestock – through low-emission development (LED) has attracted increased global attention. However, producers rarely prioritize emission reduction in their day-to-day practices, resulting in a mismatch between global and national environmental policies and local development interests. This raises the urgency of identifying overlapping solution spaces that would address global and national environmental targets and farmers’ production goals. The objective of this study is to identify pathways for scaling LED that better account for divergent smallholder capabilities, strategies, and interests. A multivariate cluster analysis was used to evaluate producer heterogeneity. The analysis utilized data from 1176 household surveys in Tanzania. Informed by these results, stakeholder workshops were held to identify how each group is uniquely constrained in the adoption of LED practices and viable paths forward. Our results reveal six distinct farmer types, distinguishable by their asset base, livestock ownership, cattle breeds, access to market, and income diversity. The six groups presented three levels of LED uptake, high, moderate, and low. Variants of technological packages and market-based interventions, access to better quality inputs, and extension services will be more impactful when correctly matched to producers’ asset portfolios, interests, and needs for the high and moderately intensifying producers. However, interventions that address both the knowledge and resource gaps for producers who demonstrate low uptake of LED will be more appropriate. Achieving GHG reduction will be modest from already intensifying groups and the low uptake groups, while moderately intensifying groups present the highest leverage for increased GHG reduction potential. This highlights how taking a food system approach rather than a technological package would be more beneficial especially in targeting groups that are not interested in LED. This study challenges the conceptualization of LED as a simple technological fix. We demonstrate that LED, as currently conceptualized, is not equally accessible or appealing to everyone. Consequently, successful LED uptake is contingent on donor and state ability to match LED strategies, local development priorities, and food systems objectives to develop more targeted needs-driven implementation pathways.
Spatial distribution of degradation and deforestation of palm swamp peatlands and associated carbon emissions in the Peruvian Amazon
The vast peat deposits in the Peruvian Amazon are crucial to the global climate. Palm swamp, the most extensive regional peatland ecosystem faces different threats, including deforestation and degradation due to felling of the dominant palm Mauritia flexuosa for fruit harvesting. While these activities convert this natural C sink into a source, the distribution of degradation and deforestation in this ecosystem and related C emissions remain unstudied. We used remote sensing data from Landsat, ALOS-PALSAR, and NASA’s GEDI spaceborne LiDAR-derived products to map palm swamp degradation and deforestation within a 28 Mha area of the lowland Peruvian Amazon in 1990–2007 and 2007–2018. We combined this information with a regional peat map, C stock density data and peat emission factors to determine (1) peatland C stocks of peat-forming ecosystems (palm swamp, herbaceous swamp, pole forest), and (2) areas of palm swamp peatland degradation and deforestation and associated C emissions. In the 6.9 ± 0.1 Mha of predicted peat-forming ecosystems within the larger 28 Mha study area, 73% overlaid peat (5.1 ± 0.9 Mha) and stored 3.88 ± 0.12 Pg C. Degradation and deforestation in palm swamp peatlands totaled 535,423 ± 8,419 ha over 1990–2018, with a pronounced dominance for degradation (85%). The degradation rate increased 15% from 15,400 ha y−1 (1990–2007) to 17,650 ha y−1 (2007–2018) and the deforestation rate more than doubled from 1,900 ha y−1 to 4,200 ha y−1. Over 1990–2018, emissions from degradation amounted to 26.3 ± 3.5 Tg C and emissions from deforestation were 12.9 ± 0.5 Tg C. The 2007–2018 emission rate from both biomass and peat loss of 1.9 Tg C yr−1 is four times the average biomass loss rate due to gross deforestation in 2010–2019 reported for the hydromorphic Peruvian Amazon. The magnitude of emissions calls for the country to account for deforestation and degradation of peatlands in national reporting.
Refining greenhouse gas emission factors for Indonesian peatlands and mangroves to meet ambitious climate targets
For countries’ emission-reduction efforts under the Paris Agreement to be effective, baseline emission/removals levels and reporting must be as transparent and accurate as possible. For Indonesia, which holds among the largest area of tropical peatlands and mangrove forest in the world, it is particularly important for these high-carbon ecosystems to produce high-accuracy greenhouse gas inventory and to improve national forest reference emissions level/forest reference level. Here, we highlight the opportunity for refining greenhouse gas emission factors (EF) of peatlands and mangroves and describe scientific challenges to support climate policy processes in Indonesia, where 55 to 59% of national emission reduction targets by 2030 depend on mitigation in Forestry and Other Land Use. Based on the stock-difference and flux change approaches, we examine higher-tier EF for drained and rewetted peatland, peatland fires, mangrove conversions, and mangrove on peatland to improve future greenhouse gas flux reporting in Indonesia. We suggest that these refinements will be essential to support Indonesia in achieving Forest and Other Land Use net sink by 2030 and net zero emissions targets by 2060 or earlier.
Many countries have recently adopted bioenergy as part of a critical strategy to reduce greenhouse gas (GHG) emissions to meet targets under the Paris Climate Agreement. Because of increased efficiency and lower production costs, along with legislative support and investment incentives, bioenergy use is swiftly becoming a renewable energy substitute for fossil fuels. The study provides a better understanding of bioenergy issues, potential and sustainability to inform countries in the global South and provide guidance on integrating bioenergy into their national energy plans by proposing a simplified sustainability framework for wood-based bioenergy.
Arguments are reviewed against biomass energy expansion, mainly developed in the context of the global north. The benefits of biomass energy expansion are also reviewed with a focus on conditions common to the global south. A sustainability framework is presented to illustrate better use of low-value land resources, produce bioenergy, restore ecosystem services, and mitigate and adapt to climate change. The study recommends guidance to establish sustainable, wood-based bioenergy supply in developing countries in the global South, which help ensure that biomass supply chains adhere to the principles and criteria of bioenergy sustainability.
Many countries have recently adopted bioenergy as part of a critical strategy to reduce greenhouse gas (GHG) emissions to meet targets under the Paris Climate Agreement. Because of increased efficiency and lower production costs, along with legislative support and investment incentives, bioenergy use is swiftly becoming a renewable energy substitute for fossil fuels. The study provides a better understanding of bioenergy issues, potential and sustainability to inform countries in the global South and provide guidance on integrating bioenergy into their national energy plans by proposing a simplified sustainability framework for wood-based bioenergy.
Arguments are reviewed against biomass energy expansion, mainly developed in the context of the global north. The benefits of biomass energy expansion are also reviewed with a focus on conditions common to the global south. A sustainability framework is presented to illustrate better use of low-value land resources, produce bioenergy, restore ecosystem services, and mitigate and adapt to climate change. The study recommends guidance to establish sustainable, wood-based bioenergy supply in developing countries in the global South, which help ensure that biomass supply chains adhere to the principles and criteria of bioenergy sustainability.