Methane Reduction Research Articles

A measurement-based upstream oil and gas methane inventory for Alberta, Canada reveals higher emissions and different sources than official estimates

Mitigation actions and regulations to meet critical 2030 methane reduction targets under the Global Methane Pledge are hampered by uncertainty in true levels of emissions and source breakdowns. Here we present a measurement-based, source-resolved, hybrid top-down/bottom-up methane inventory for conventional upstream oil and gas operations in Canada’s largest oil and gas-producing province, Alberta. The derived 2021 inventory of 1337 kt/y is approximately 1.5× the official federal inventory and matches independent top-down aerial mass-balance and satellite estimates within uncertainties. Major sources are starkly different from official estimates, with venting (e.g., uncontrolled tanks, pneumatics, unlit flares) comprising almost two-thirds of emissions implying important mitigation opportunities. Derived methane intensities, while similar to U.S. basins, are approximately 4× those in neighbouring British Columbia and further reveal order-of-magnitude differences among individual anonymized companies at directly comparable facility types. This highlights the importance of independent monitoring, reporting, and verification to ensure collective success in reducing emissions.

Dose- and substrate-dependent reduction of enteric methane and ammonia by natural additives in vitro.

Ruminants contribute to global warming by emitting greenhouse gasses, particularly methane (CH4) which is a product of rumen fermentation. The use of feed additives able to modulate rumen fermentation is a promising strategy to reduce enteric CH4 and ammonia (NH3) emissions. Among the various strategies investigated, plant secondary metabolites (PSMs) have attracted attention due to their apparent potential to reduce enteric CH4 and NH3 emissions, and it would be possible to use such compounds as feed additives in organic production systems. In an in vitro system simulating rumen fermentation, we have tested the impact of different classes of naturally occurring PSMs; catechin and quercetin (flavonoids), salicylic acid (phenolic acid) and tannic acid (hydrolysable tannin). The PSMs were added to two different basal feeds (maize and grass silages) at three inclusion doses 1.5, 3 and 6% of the feed dry matter (DM). CH4 production was significantly lowered upon addition of quercetin to two basal feeds at doses of 3 and 6%, and this without changes in concentrations of total volatile fatty acid (VFA) produced during fermentation. Quercetin, as the only tested additive, reduced CH4 production, and when added to maize silage and grass silage, the reduction increased linearly with increasing dose, ie., by 51 and 43%, respectively, at a dose of 3% of feed DM and by 86 and 58%, respectively, at a dose of 6% of feed DM. Moreover, quercetin significantly reduced NH3 concentration by >12% at doses of 3 and 6% in feed DM irrespective of the basal feed used as compared to when the basal feeds were incubated alone. Although none of the other additives affected CH4 formation, several additives had significant impacts on concentrations of NH3 and VFAs in the incubated fluid after fermentation. This study demonstrated a dose-dependent ability of quercetin to reduce CH4 emission from rumen fermentation, however, the magnitude of the suppression of CH4 depended on the basal feed. Furthermore, quercetin reduced NH3 concentration irrespective of the basal feed type. These findings encourage to in vivo studies to verify whether quercetin can reduce CH4 emission also in cows.

An Epifaunal Community Succession Sequence Driven by the Biogeochemical Footprint With Different Methane Seepage Intensity of the Deep Seafloor

AbstractMethane seepage, generated from natural processes or gas hydrate dissociation, drives the development of cold seep ecosystems and leads to atmosphere methane emission, thereby influencing climate change. Uncovering the intrinsic interactions among methane seepage intensities, biogeochemical processes in the sediment, and benthic community characteristics at the seafloor is essential to clarify and predict the ultimate fate of methane leakage from the deep sea. Here, we conducted a systematic investigation of methane intensity, pore fluid migration characteristics, sediment mineral fraction features, and the evolution of biological communities in areas with different methane intensities. Furthermore, analyses of high‐resolution images, pore fluid geochemical feature, and lithologic characteristics of the sediment in the Haima cold seep were also carried out in this study. The results showed that, in areas with different methane intensities, organic matter sulfate reduction and anaerobic oxidation of methane were heterogeneous. The heterogeneity led to the methane transformation zones at different depths, which changed the mineral composition of the sediment and biological communities in the seabed. In addition, a hypothesis of successional sequence of biomes in cold seep was established. This study revealed that the methane seepage intensity was a key factor in determining the biogeochemical process in the sediment of cold seep. The coupling effects of biogeochemical processes and methane seepage intensities dominated the community succession of cold seep. These findings could provide important implications for understanding the dynamic deep marine methane cycle mechanism and the contribution of deep‐sea methane released to climate change.

Anti-nutrient contents and methane reduction potential of medicinal plants from maize stover based diet

Greenhouse gas emissions from Ethiopian agriculture are significantly increasing, with the largest share is from enteric fermentation and manure left on pasture. An investigation was conducted to evaluate the anti-nutrient composition and effect of commonly used medicinal plant extracts on enteric methane emission from fibrous feeds using maize stover as substrate feed. Total phenols, flavonoid, tannin and essential oil contents were analyzed using established standards. Effects of leaf extracts of Acacia nilotica, Azadirachta indica, three varieties of Cymbopogon citratus (Cymbopogon citratus-I, Cymbopogon citratus java and Cymbopogon citratus upper awash), Leucaena leucocephala, Moringa stenopetala, three varieties of Rosmarinus officinalis (Rosmarinus officinalis I, Rosmarinus officinalis II and Rosmarinus officinalis III) and Thyme schimperi, seed of three Coriandrum sativum varieties (Coriandrum sativum Batu, Coriandrum sativum Tulu and Coriandrum sativum Waltai) and root of Echinops kebericho on total gas production, digestibility and methane production of maize stover were investigated at different doses using the standard procedures. The results indicated that leaf extracts of Acacia nilotica had the highest (P < 0.001) total phenolic and total tannin contents. Compared to other evaluated plant species, all varieties of Cymbopogon citratus had the highest (P < 0.001) flavonoid content. Significantly high (P < 0.001) essential oil content was observed in Rosmarinus officinalis II than other varieties of Rosmarinus officinalis and other plant species. Significant reduction (P < 0.001) of methane production was observed with extracts of Cymbopoon citratus java (22.5 % less methane than the control) and thyme schimperi (16.7 % less methane than the control) at dose of 50 mg/kg DM. There was also significant (P < 0.001) interaction effect between plant species and dose rates at 50 mg/kg DM for both plant species. It can be concluded that the use of 50 mg/kg DM of Cymbopoon citratus java and Thyme schimperi extract to maize stover reduced methane production without negatively affecting feed digestibility. Further studies are necessary to examine the storability of the extracts in different time durations and evaluate their effects in vivo with animals.

Methane Emission Reduction Technologies for Natural Gas Engines: A Review

This review summarizes technologies to reduce methane emissions from natural gas engines with a focus on exhaust treatment. As regulations on methane emissions from natural gas facilities become more restrictive, methane emission reduction technologies become increasingly important. Methane is the second most prevalent human-generated greenhouse gas. In 2020, 197,000 metric tons of methane were released as a result of methane slip. In-cylinder methods such as optimized valve timing and crevice volume reduction are effective in reducing methane slip. Exhaust treatment methods such as catalytic oxidizers and regenerative thermal oxidizers can achieve near 100% methane reduction under certain conditions. Implementation of hydrogen blending and exhaust gas recirculation systems results in a decrease in methane emissions of between 20 and 30%. Future research should focus on testing full-scale catalytic oxidation systems on lean-burn natural gas engines. Research should also focus on implementing regenerative thermal oxidizers on natural gas engines, as well as combining hydrogen blending with these techniques.

Mapping methane reduction potential of tidal wetland restoration in the United States

Coastal wetlands can emit excess methane in cases where they are impounded and artificially freshened by structures that impede tidal exchange. We provide a new assessment of coastal methane reduction opportunities for the contiguous United States by combining multiple publicly available map layers, reassessing greenhouse gas emissions datasets, and applying scenarios informed by geospatial information system and by surveys of coastal managers. Independent accuracy assessment indicates that coastal impoundments are under-mapped at the national level by a factor of one-half. Restorations of freshwater-impounded wetlands to brackish or saline conditions have the greatest potential climate benefit of all mapped conversion opportunities, but were rarer than other potential conversion events. At the national scale we estimate potential emissions reduction for coastal wetlands to be 0.91 Teragrams of carbon dioxide equivalents year−1, a more conservative assessment compared to previous estimates. We provide a map of 1,796 parcels with the potential for tidal re-connection.

Mutual disposal of municipal solid waste and flue gas on isolated islands

Municipal solid waste (MSW) management in rural and remote areas (e.g., isolated islands) is a noteworthy issue. Transportation of MSW from isolated islands to the mainland requires large-scale energy, so it demands a high amount of diesel fuel in diesel generators. To alleviate environmental pollution and energy consumption during transportation, this paper proposes a mutual disposal strategy for MSW and fuel gas from diesel generators and explores the feasibility and potential benefits based on MSW drying experiment in a self-designed device. The following were the primary conclusions: (1) the flue gas could provide sufficient heat energy for drying MSW, and the effective utilization rate can reach 60.22 ± 2.88%. It would take 60–85 min to dry MSW below 200 °C. (2) Within the permissible limits of environmental standards, the MSW contributes to the reduction of particulate matter and methane in the flue gas, while the carbon monoxide, nitric oxide, and non-methane hydrocarbon contents increase due to thermal decomposition of the MSW. The global warming potential of the carbon in the treated gas can be decreased by 16.94%, and the nitric oxide contributes to carbon emission reduction. (3) The proposed mutual disposal strategy could alleviate issues in landfill leachate and simplify the treatment technology, leading to subsequent environmental, economic, and technical benefits.

Methane reduction by quercetin, tannic and salicylic acids: influence of molecular structures on methane formation and fermentation in vitro

Plant secondary metabolites (PSMs) can potentially reduce ruminal methane formation. However, related to differences in their molecular structures, it is not yet clear what causes an anti-methanogenic effect. In an in vitro system simulating rumen fermentation, we investigated the impact of eight compounds with distinct chemical characteristics (gallic and salicylic acids, tannic acid, catechin, epicatechin, quercetin, rutin, and salicin) when added to a basal feed (maize silage) at a concentration of 12% of the feed dry matter. After 48 h of incubation in buffered rumen fluid, methane production was significantly lowered by quercetin (43%), tannic acid (39%) and salicylic acid (34%) compared to the control (maize silage alone) and without changes in total volatile fatty acid production during fermentation. No other PSM reduced methane formation as compared to control but induced significant differences on total volatile fatty acid production. The observed differences were related to lipophilicity, the presence of double bond and carbonyl group, sugar moieties, and polymerization of the compounds. Our results indicate the importance of distinct molecular structures of PSMs and chemical characteristics for methane lowering properties and volatile fatty acid formation. Further systematic screening studies to establish the structure–function relationship between PSMs and methane reduction are warranted.

Petrofabric and geochemical constraints on the origin of Liuyang chrysanthemum stone, South China

Chrysanthemum stone refers to a radial and chrysanthemum–like mineral aggregate. Liuyang chrysanthemum stone, distributed in the carbonate of the Permian Chihsian Formation in South China, has become a rare natural art treasure due to its unique radial shape. The lack of effective constraints on the petrography and geochemistry of the chrysanthemum stone in Liuyang restricts the understanding of its origin. Hence, petrography analysis and Raman microprobe spectroscopy were used to study the mineral compositions and textural characteristics of the Liuyang chrysanthemum. Element and isotope geochemistry studies were conducted to discuss the sedimentary environment, material source, and formation mechanism. The Liuyang chrysanthemum stone was formed in the period of aragonite sea, and developed in dark gray limestone as a white radial mineral aggregate. The primary mineral is celestite, a minor amount of which was filled with and metasomatized by calcite. Trace element characteristics (δCe = 0.46–0.70, V/Cr = 1.28–1.51, Ni/Co = 2.14–4.89, Sr/Ba = 14.42–45.17) and carbon and oxygen isotopic compositions (δ13CV–PDB = 3.0 ‰–3.8 ‰, δ18OV–PDB = 5.2 ‰–4.8 ‰) of the host rocks indicate an aerobic marine sedimentary environment. The significant difference in sulfur isotopic compositions between the chrysanthemum stone (δ34S = 29.4 to 28.1 ‰) and the host rocks (δ34S = –29.4 to –28.1 ‰) indicates that bacterial sulfate reduction (BSR) and anerobic oxidation of methane (AOM) has occurred. Petrography, trace element and C–O–S isotope geochemistry of the Liuyang chrysanthemum stone had revealed the formation process of the chrysanthemum stone. The organic matter was decomposed by O2 and produced CO2 in the aerobic marine sedimentary environment. With the continuous sedimentation and the oxygen consumption, the early sedimentary carbonate and bioclastic was gradually separated from the relatively aerobic environment. An anoxic sedimentary–diagenetic environment was formed and the BSR occurred, during which SO42– participated in the degradation of organic matter as an electron acceptor. The bacteria preferentially absorbed the light 32SO42– in pore water to produce 32S–rich FeS2 in the host rocks and the heavy SO42– was combined with the Sr2+ released by aragonite dissolved by the accumulated CO2 to precipitate the celestite. HCO3– accumulated during the AOM and the BSR resulted in the replacement of the celestite by the calcite.

Nexus between natural resource depletion and rent and COP26 commitments: Empirical evidence from Vietnam

The goal of Vietnam to achieve certain emission level by 2030 is quite challenging even though the country is fully aware of the threats posed by climate complexities. In this regard, natural resources are influencing ingredients of eco-system and play a major role in environmental degradation. As reduction of methane and carbon emissions along with other GHG emissions were of the main concern of CO26 conference. Thereby, it is essential to get the fresh insights regarding the role of natural resources depletion and rent on methane emissions in Vietnamese context. By employing treadmill production theory, the present article hypothesized environmental quality deteriorates when economic activities increases and natural resources are highly exploited. Secondary data was extracted from WDI covering the time span of 1986–2020. Bayesian Auto-regressive Distributed Lags (BARDL) technique was used to test the hypothesis. From findings, it is revealed that all the chosen variable are positively associated with methane emissions, hence supporting the theory, however, the results contradict with certain studies who claims that the variables especially natural resource depletion and natural resource rent are helpful in reducing methane emissions. In the light of extracted evidences, the authors suggestions some implication that are to be helpful for country to achieve COP26 targets.

Effect of fumaric acid in combination with Asparagopsis taxiformis or nitrate on in vitro gas production, pH, and redox potential

Reduction in enteric methane (CH4) emissions from cattle can be achieved through use of feed additives, which often results in increased emission of hydrogen (H2). The objective of this study was to investigate in vitro effects of a known hydrogen sink, fumaric acid, in combination with either of 2 methane inhibitors, the macroalga Asparagopsis taxiformis or nitrate, on CH4 and H2 production, feed degradability, pH, and redox potential. A corn silage (0.5 g; control) was incubated in buffered rumen fluid with the addition of 0.025 g of nitrate (Nit), 0.025 g of dried A. taxiformis (Asp), 0.025 g of nitrate + 0.025 g of fumaric acid (Nit+Fum), or 0.025 g of dried A. taxiformis + 0.025 g of fumaric acid (Asp+Fum). Accumulated gas production was determined using the AnkomRF system equipped with airtight gasbags. There were 9 replicates per treatment with 3 replicates per treatment stopped after 24, 36, and 48 h of incubation. The amount of undegraded feed was determined by filtration. Gas composition was determined by gas chromatography. Degradable dry matter, degradable organic matter, pH, redox potential, and gas production data were analyzed using a mixed model. Asp and Asp+Fum reduced CH4 production by 98% or greater at all incubation times, whereas Nit and Nit+Fum reduced CH4 production (mL of CH4/g of dry matter) by 52% to 63% compared with the control. Hydrogen was only detectable in gas from Asp and Asp+Fum treatments, with no difference in H2 production between the 2 treatments. The treatments had only minor effects on redox potential in the fermented rumen fluid, and pH was lowest for treatments including A. taxiformis. In conclusion, both A. taxiformis and nitrate reduced CH4 production. Fumaric acid in combination with A. taxiformis did not reduce H2 production, and treatments including nitrate did not result in any detectable levels of H2. Future dose-response in vitro studies will contribute to investigating the potential of fumaric acid as a hydrogen sink during CH4 mitigation.

Global environmental implications of atmospheric methane removal through chlorine-mediated chemistry-climate interactions

Atmospheric methane is both a potent greenhouse gas and photochemically active, with approximately equal anthropogenic and natural sources. The addition of chlorine to the atmosphere has been proposed to mitigate global warming through methane reduction by increasing its chemical loss. However, the potential environmental impacts of such climate mitigation remain unexplored. Here, sensitivity studies are conducted to evaluate the possible effects of increasing reactive chlorine emissions on the methane budget, atmospheric composition and radiative forcing. Because of non-linear chemistry, in order to achieve a reduction in methane burden (instead of an increase), the chlorine atom burden needs to be a minimum of three times the estimated present-day burden. If the methane removal target is set to 20%, 45%, or 70% less global methane by 2050 compared to the levels in the Representative Concentration Pathway 8.5 scenario (RCP8.5), our modeling results suggest that additional chlorine fluxes of 630, 1250, and 1880 Tg Cl/year, respectively, are needed. The results show that increasing chlorine emissions also induces significant changes in other important climate forcers. Remarkably, the tropospheric ozone decrease is large enough that the magnitude of radiative forcing decrease is similar to that of methane. Adding 630, 1250, and 1880 Tg Cl/year to the RCP8.5 scenario, chosen to have the most consistent current-day trends of methane, will decrease the surface temperature by 0.2, 0.4, and 0.6 °C by 2050, respectively. The quantity and method in which the chlorine is added, its interactions with climate pathways, and the potential environmental impacts on air quality and ocean acidity, must be carefully considered before any action is taken.

Evaluation of Methane Emission Reduction Potential of Water Management and Chinese Milk Vetch Planting in Hunan Paddy Rice Fields

In order to explore the methane reduction potential with two scenarios of water management and Chinese Milk Vetch return, we calculated the methane emissions of Hunan Province rice fields in 2019 using the SECTOR tool based on Excel and released by the International Rice Research Institute. Thus, we preliminarily established an agricultural carbon emissions monitoring, reporting, and verification (MRV) system. The results showed that: (1) There was significant spatial variation in methane emissions in Hunan rice fields, with higher emissions in both the south and north and lower emissions in the east and west. Late rice was the main contributor to methane emissions, and the cities of Changde, Hengyang, Yueyang, and Shaoyang were high-emission areas due to differences in rice planting types and areas. Compared with flooding (1275.75 Gg), optimized water management measures (mid-drainage and AWD irrigation) reduced methane emissions by 29~45% (905.79 and 701.66 Gg, respectively). (2) Under the same nitrogen input conditions, compared with a solely straw return (375.24 Gg), combining green manure with straw return could partially reduce methane emissions from Hunan super hybrid rice (327.63 Gg). Compared with the control fertilizers (404.28 Gg), the reduction rates of winter-planted Chinese Milk Vetch, the return of rice straw, and the incorporation of both Chinese Milk Vetch and straw were 7.19%, 13.01%, and 18.96%, respectively. Based on scientific accounting tools, a preliminary MRV system for rice field carbon emissions was established. Under the national demand for reducing fertilizer use and increasing efficiency, equal nitrogen organic amendments could effectively contribute to the development of green, low-carbon, and high-quality agriculture.

Anthelmintic activity of Carica pubescens aqueous seed extract and its effects on rumen fermentation and methane reduction in Indonesian thin-tailed sheep: An in vitro study.

Seeds from Carica pubescens were observed to be abundant as waste. This waste contains active plant compounds whose utilization has not been studied in the livestock sector. This study was conducted to evaluate the potential of an aqueous seed extract of Carica pubescens (ASE) as an anthelmintic agent during rumen fermentation and methane reduction. Aqueous seed extract of Carica pubescens was prepared from C. pubescens cultivated in Wonosobo, Indonesia. Phytochemical analyses were performed to quantify the secondary metabolite content of ASE. In vitro adult worm mortality tests, scanning electron microscopy, and gas production tests were conducted to evaluate rumen characteristics, methane reduction, and the potential of ASE as an anthelmintic against Haemonchus contortus. Adult worms and ruminal fluid were collected from Indonesian thin-tailed sheep. Two-way analysis of variance followed by Tukey's test was performed using the Statistical Package for the Social Sciences® 21.0 software to detect significant differences. In vitro study results showed that 1-5% ASE inhibited H. contortus after the 1st h of incubation, and 5% ASE suppressed 100% of adult H. contortus worms in the 5th h. Scanning electron microscopy analysis of ASE-treated worms ASE revealed damaged cuticle structures. ASE had no significant effect on pH, NH3, volatile fatty acid, acetate, propionate, butyrate, acetate: propionate, or microbial protein in rumen fluid (p > 0.05). The in vitro feed fermentation results showed that ASE significantly affected methane reduction. The inclusion of up to 5% ASE in sheep diets may serve as a potential alternative anthelmintic against H. contortus as well as a methane reduction agent, without deleterious effects on rumen fermentation.

Capric and lauric acid mixture decreased rumen methane production, while combination with nitrate had no further benefit in methane reduction

Abstract This study aimed to evaluate the methane-reducing potential of individual and combined treatments of low levels of nitrate (NIT) and a mixture of capric/lauric acid (CL) in dairy cows. Both in vitro and in vivo experiments were conducted. In the in vitro experiment, the anti-methanogenic effects of NIT (1.825 mmol/l) and CL (250 mg/l; capric acid, 125 mg/l + lauric acid, 125 mg/l) were evaluated in a 2 × 2 factorial design using consecutive batch incubations with rumen fluid. The NIT and CL reduced (P&lt;0.05) methane production by 9.2% and by 21.3%, respectively. However, combining NIT with CL did not show (P&gt;0.05) any benefit in methane reduction compared to the use of CL alone. In the in vivo experiment, eight multiparous dry Holstein cows were fed two diets in a crossover design for two 21-day periods (14 days of adaptation and 7 days of sampling). The treatments were: 1) silage-based basal diet + 100 g stearic acid per cow/d (CON) and 2) silage-based basal diet + 50 g capric acid + 50 g lauric acid per cow/d (CL). Gas emissions were measured using open-circuit respiration chambers. Methane production (g/d) was reduced (by 11.5%; P = 0.012) when the diet was supplemented with CL. However, supplementation with CL increased ruminal ammonia-N concentration (by 28.5%; P = 0.015) and gas ammonia production (g/d; by 37.2%; P = 0.005). Ruminal pH, protozoa count, and total and individual volatile fatty acid concentrations (VFA ) did not differ (P&gt;0.05) between the treatments. Treatment did not affect the intake and apparent total tract digestibility (P&gt;0.05). In conclusion, our results suggest that low CL levels have anti-methanogenic potential. However, low levels of CL may compromise nitrogen use efficiency.

Assessing the effectiveness and efficiency of methane regulations in British Columbia, Canada

ABSTRACT Many jurisdictions are introducing methane reduction policy as part of climate commitments, with a focus on the oil and gas supply chain. Periodic comprehensive leak detection and repair (LDAR) surveys or screening leak detection and repair surveys are required in the British Columbia, Canada oil and gas sector to reduce unintentional methane emissions caused by leaking infrastructure. By finding and fixing leaks quickly, emissions of methane, a potent greenhouse gas, are reduced. In this study, we explored how effectively British Columbia’s regulation, deposited in December 2018, made progress towards meeting the policy objective of a 45% decrease in methane emissions by 2025 from a 2014 baseline. We evaluated the performance and cost effectiveness of regulatory-prescribed LDAR programmes using data collected by the BC Energy Regulator (formerly BC Oil and Gas Commission) for the 2020 year, and survey cost data submitted by service providers. We found that the new regulation was only partially effective due to low compliance rates. We also observed heavy tail leak distributions in LDAR data collected by service companies, but comparatively narrow leak distributions in data from permit holders who internalized LDAR operations, suggesting a difference in work practice or the use of equipment. Comprehensive leak detection surveys were found to be more cost efficient ($23 CAD/tCO2e reduced) compared to screening surveys ($1,787 CAD/tCO2e reduced) because more methane leaks are detected in comprehensive assessments. To meet methane reduction targets, we recommend that: 1) jurisdictions work to improve compliance rates by introducing minimum administrative penalties specific to noncompliance; 2) that all future LDAR surveys are instrument-based; 3) limiting turnaround time limits so that repairs are not delayed indefinitely; and 4) that LDAR completed internally by permit holders undergo independent third-party verification.

Integrated nutrient management for improving crop yields, soil properties, and reducing greenhouse gas emissions

Recently, most agrarian countries have witnessed either declining or stagnant crop yields. Inadequate soil organic matter (SOM) due to the poor physical, chemical, and biological properties of the soil leads to an overall decline in the productivity of farmlands. Therefore, the adoption of integrated nutrient management (INM) practices is vital to revive sustainable soil health without compromising yield potential. Integrated nutrient management is a modified nutrient management technique with multifarious benefits, wherein a combination of all possible sources of plant nutrients is used in a crop nutrition package. Several studies conducted in various parts of the world have demonstrated the benefits of INM in terms of steep gain in soil health and crop yields and at the same time, reducing greenhouse gas emissions and other related problems. The INM practice in the cropped fields showed a 1,355% reduction in methane over conventional nutrient management. The increase in crop yields due to the adoption of INM over conventional nutrient management was as high as 1.3% to 66.5% across the major cropping systems. Owing to the integration of organic manure and residue retention in INM, there is a possibility of significant improvement in soil aggregates and microbiota. Furthermore, most studies conducted to determine the impact of INM on soil health indicated a significant increase in overall soil health, with lower bulk density, higher porosity, and water-holding capacity. Overall, practicing INM would enhance soil health and crop productivity, in addition to decreasing environmental pollution, greenhouse gas emissions, and production costs.

Risk Management of Methane Reduction Clean Development Mechanism Projects in Rice Paddy Fields

Agriculture accounts for the largest share of anthropogenic methane emissions. Rice paddy fields emit a significant amount of methane gas worldwide. Changing paddy water management practices has an enormous potential to reduce greenhouse gases. The clean development mechanism (CDM) project uses a market mechanism to reduce methane through private participation. There are various risks associated with private investment in CDM projects, although carbon credits as an economic incentive assist in mitigating some of these risks. Farmer participation plays a key role in the success of paddy water management projects in rural areas; however, despite the significant potential to reduce global methane emissions, very few projects have been implemented. When designing a Sustainable Development Mechanism (SDM) system, it is crucial to understand why the market mechanism in the existing CDM projects has failed. This study identifies and categorizes the risks and barriers to paddy water management in CDM projects and analyzes risk management options in CDM projects in India, Indonesia, and Mozambique. The results of this study showed that aside from economic risks, barriers to the application of technology in the field pose critical risks. The lack of knowledge and implementation experiences in rural areas increases barriers to practice. This in turn causes risk of difficulties in technology transfer which can be alleviated by improving awareness and introducing new knowledge through education and training in rural project implementation. Additionally, we highlight the importance of international efforts to build governance between the private and public sectors and promote technology transfers through multi-stakeholder engagement. This study provides specific information to encourage methane reduction worldwide and vitalize rice paddy water management in carbon reduction projects.

Methane Reduction Potential of Hydroponic Fodders and Combination of Hydroponic Fodder Bajra with Anionic Salts in Increasing Serum Calcium Level of Transition Cows

Background: The study reported in this research is to assess the methane reduction potential of hydroponic fodders and its novel combination with anionic salts on the serum calcium level in transition cows, the period cows are prone to metabolic disorders. Methods: A growth trial of hydroponic fodders to assess the biomass yield and an in vitro gas production study was conducted to assess the methane production on inclusion of different hydroponic fodders with that of conventionally cultivated fodders along with paddy straw and concentrate feed. A feeding trial was also conducted in 16 transition cows (farm and field conditions) to assess the serum calcium level through feeding anionic salts viz., calcium sulphide and magnesium chloride along with hydroponic fodder bajra. Result: Significantly (P less than 0.05) lowest methane production was observed in paddy straw, hydroponic fodder bajra, concentrate feed group compared to other treatment groups. Anionic salts supplementation for three weeks prior to calving resulted in significant (P less than 0.05) increase in the serum calcium levels. In post supplementation, average increase in serum calcium level is 0.93 mg/dl, an increase by 10.80 per cent. Further, feeding cost of anionic salts (Calcium sulphide and magnesium chloride) for three weeks (21 days) is only INR 55.65/-.

Methane Emissions Quantification and Resulting Methane Emissions Reduction in the Permian Basin Enabled by Automated Unmanned Systems

Summary Traditional methods for monitoring emissions from production operations have typically used optical gas imaging cameras or Method 21 systems, based on an intermittent basis to determine and document methane gas leaks, which are then subsequently identified for repair under the US Code of Federal Regulations (2017). These optical gas imaging emissions monitoring surveys can have a subjective bias, are highly conditional on the skill of the camera operator, and are an inexact method of measuring the quantity of the leak rate. With a renewed industry emphasis on methane emissions measurement and reduction, this paper describes a case study using a high-sensitivity sensor technology (laser absorption spectrometry) specifically targeting methane emissions, the unique capabilities engendered by its deployment on unmanned aerial systems (UAS), the leveraging of automation in field-operation and data analysis, and the system’s successful utilizationin enabling emissions limitations over several production sites in the Permian Basin. The use of automation enabled categorization of the leak type and intensity, and triage according to leak rate, facilitating prompt remedial action and directly limiting emissions. By automating the comprehensive flight paths specific to equipment groups (e.g., compressors, tanks, and flares), targeted repeat surveys confirmed that specific leaks were fixed, emphasizing a general downward trend in overall site- and asset-level emissions. These surveys were completed in 22.5 minutes, on average, at each of the five sites. Additionally, the use of high-resolution UAS-generated orthomosaic maps enabled the direct placement of emissions data into the context of the operations at the time of the survey, facilitating the generation of automated actionable reports, helping direct repair teams, and resulting in effective and necessary fixes. Furthermore, the campaign validated that following the set up of the initial survey, subsequent regular, repeat surveys could be commissioned at the “push of a button,” yielding reliable, actionable emissions data, with a direct impact on both environmental (6% reduction in emissions) and financial impact.