Methane Gas Emissions Research Articles

Surviving the Downturn: Oil Executives See Continued Tough Times Ahead

Surviving the Downturn: Oil Executives See Continued Tough Times Ahead Trent Jacobs, JPT Senior Technology Writer, Stephen Rassenfoss, JPT Emerging Technology Senior Editor Enough dust has settled over the past year to give the global oil and gas business a clearer view of its new landscape. Holding little back, speakers at the annual IHS CERAWeek conference in February discussed how the industry has been shaped by the disruptive impact of North American shale production and predicted that many more months of financial pressure will spell the end for some companies. The current industry situation is often compared with the last prolonged downturn in the 1980s—used by many in the oil patch as the measuring stick for rough times. But for Ali Al-Naimi, the Saudi Arabian minister of petroleum, the contributing factors are different this time around. Speaking in Houston at the annual gathering of top executives from operators, national oil companies, the service sector, and government, he explained that today’s crude market includes an expanded roster of producing nations and is under the influence of financial instruments that did not exist 3 decades ago. Al-Naimi then disputed the idea that his country is engaged in a global battle for market share that some claim is prolonging the bust. “Let me say for the record, again, we have not declared war on shale or on production from any given country or company— contrary to all the rumors that you hear and see,” he said. “We are responding to challenging market conditions and seeking the best possible outcome in a highly competitive environment.” Nevertheless, Al-Naimi also argued that the market is simply not big enough for high-cost producers, and said they have three options: lower their costs, borrow more money, or liquidate. “It sounds harsh, and unfortunately it is, but it is the most efficient way to rebalance markets,” he said. “Cutting low-cost production to subsidize higher-cost supplies only delays an inevitable reckoning.” On the topic of a potential production freeze proposed by a minority group of the Organization of Petroleum Export Countries (OPEC) and Russia, Al-Naimi said such a move could happen but ruled out any notion that Saudi Arabia would cut oil production. World Must ‘Tighten Valves’ on Methane Emissions Joel Parshall, JPT Features Editor The importance of reducing emissions of methane, a short-lasting but powerful atmospheric greenhouse gas (GHG), received close attention from panelists at an IHS CERAWeek strategic dialogue, Tightening the Valves on Global Methane Emissions. A frequently asked question is “why all this focus on methane,” said Mark Brownstein, vice president for climate and energy at the Environmental Defense Fund (EDF). “Isn’t the issue carbon dioxide [CO2]? Actually, it’s both.” Methane emissions remain in the atmosphere for much less time than CO2 but are a far more powerful pollutant while they last. “It’s thought that 25% of the warming that we’re experiencing right now on the planet is because of methane emissions,” Brownstein said. “A 45% reduction in oil and gas industry methane emissions would have the same impact over 20 years as closing one-third of the world’s coal [-fired power] plants.”

Effect of By-Product Gypsum Fertilizer on Methane Gas Emissions and Rice Productivity in Paddy Field

Rice cultivation in paddy field affects the global balance of methane (CH₄) as a key greenhouse gas. To evaluate a potential use of by-product gypsum fertilizer (BGF) in reducing CH₄ emission from paddy soil, CH₄ fluxes from a paddy soil applied with BGF different levels (0, 2, 4 and 8 Mg ha -1 ) were investigated by closed-chamber method during rice cultivation period. CH₄ flux significantly decreased (p -1 of BGF addition in soil reduced CH₄ flux by 60.6% compared to control. Decreased soil redox potential (Eh) resulted in increasing CH₄ emission through a CO₂ reduction reaction. The concentrations of dissolved calcium (Ca) and sulfate ion (SO₄ 2- ) in soil pore water were significantly increased as the application rate of BGF increased and showed negatively correlations with CH₄ flux. Decreased CH₄ flux with BGF application implied that SO₄ 2- ion led to decreases in electron availability for methanogen and precipitation reaction of Ca ion with inorganic carbon including carbonate and bicarbonate as a source of CH₄ formation under anoxic condition. BGF application also increased rice grain yield by 16% at 8 Mg ha -1 of BGF addition. Therefore, our results suggest that BGF application can be a good soil management practice to reduce CH₄ emission from paddy soil and to increase rice yield.

Direct Seeded Rice: Potential and Constraints in Punjab

Rice production contributes to global climate change through emissions of methane and nitrous oxide gases. Further water table is lowering at an alarming rate in Punjab due to excessive drawing of groundwater for rice cultivation. Water use in rice production, therefore, needs to be decreased by increasing water-use efficiency, decreasing seepage, percolation and evaporation losses. DSR (direct seeded rice) has got the potential to improve water use efficiency, reduce other losses besides significantly reducing the methane production by producing the aerobic conditions. The FLD on DSR were conducted during 2013–14 to 2015–16 in Bathinda district of Punjab to assess prospects and constraints of DSR over NTR (normal transplanted rice). DSR has saved labour worth 5250 per hectare, irrigations to the tune of 40 per cent and has also given 2.61 per cent additional yield worth 3298 per hectare over NTR. A successful transition of rice cultivation from normal transplanting system to DSR culture demands breeding of special rice varieties and developing appropriate management strategies. Despite threats of weed flora, NO2 emissions, lodging, nutrient deficiencies and blast attack the technique, thus, need to be popularized on heavy soils through suitable policy at the state level.

Methane reductions to moderate the global warming effects

The case-study overviews the possible reduction for the methane gas emission in order to avoid of the more global warming effects and climate change caused by the human activity at latest decades. To collect international data base is for analysing and valuing methane gas emission based on the different country-groups, emphasizing responsibility of developing countries and highly developed countries for gas emission, also the methane emission based is on the economic sectors. China and India have share 8% of China and 2% of India respectively of cumulative CO2 emissions over the period 1900-2005, the US and the EU are responsible for more than half of emissions. Based on the estimation the global gas emissions of methane in the whole world has increased by 37% for period of 1990- 2030, as four decades, and this was 0,92% annual rate growth, while the OECD has increased the methane emission by 8,5% for this period, which means 0,21% growth rate annually. Scenario in developing countries for 2013-2020 the methane gas emission reduction could have been 8200 Mt of CO2e (Equivalent) and less than 10 US dollar per ton in more cost financing. Highly developed and developing economies (last one their methane emission share 56% in 1990, estimated 66,8% in 2030) increase their economic growth by mostly fossil energy resulted in increasing also methane gas emissions. The methane gas emission can be solved by those results-based-finance forms relevant to Kyoto Protocol, which can extend in the world by financial institutions.

Reconciling divergent estimates of oil and gas methane emissions

Published estimates of methane emissions from atmospheric data (top-down approaches) exceed those from source-based inventories (bottom-up approaches), leading to conflicting claims about the climate implications of fuel switching from coal or petroleum to natural gas. Based on data from a coordinated campaign in the Barnett Shale oil and gas-producing region of Texas, we find that top-down and bottom-up estimates of both total and fossil methane emissions agree within statistical confidence intervals (relative differences are 10% for fossil methane and 0.1% for total methane). We reduced uncertainty in top-down estimates by using repeated mass balance measurements, as well as ethane as a fingerprint for source attribution. Similarly, our bottom-up estimate incorporates a more complete count of facilities than past inventories, which omitted a significant number of major sources, and more effectively accounts for the influence of large emission sources using a statistical estimator that integrates observations from multiple ground-based measurement datasets. Two percent of oil and gas facilities in the Barnett accounts for half of methane emissions at any given time, and high-emitting facilities appear to be spatiotemporally variable. Measured oil and gas methane emissions are 90% larger than estimates based on the US Environmental Protection Agency's Greenhouse Gas Inventory and correspond to 1.5% of natural gas production. This rate of methane loss increases the 20-y climate impacts of natural gas consumed in the region by roughly 50%.

Effects of phytogenic feed additives on growth performance and on ammonia and greenhouse gases emissions in growing-finishing pigs

The present study was conducted to evaluate the effects of two commercial phytogenic feed additives (PFAs) on growth performance and emissions of ammonia, methane, nitrous oxide and carbon dioxide compared to an unsupplemented control. The two tested commercial PFAs contained either essential oils or a mixture of essential oils and dried herbs and spices. In addition, both PFAs delivered the same amount of Quillaja saponaria saponins to the final feed, although dosage of the products differed. The PFAs were included in cereal-based grower and finisher diets via premixes. For negative control diet a placebo premix was used. The diets were fed to a total of 81 castrated male growing-finishing pigs (45–114kg body weight, 27 per treatment) that were kept in nine gas-tight sealed chambers, each with three pens with fully slatted floors (three pigs per pen). The whole experiment lasted 72 days. Pigs were individually weighted and the feed consumption of pigs was recorded per pen at day 0, 24 and 72 of the experiment. From day 24 to day 72 (48 days) emission measurement took place.The inclusion of the PFAs significantly improved average daily feed intake (P=0.010) and average daily gain (P=0.018) of pigs over the whole trial period of 72 days compared to the negative control. Feed conversion ratio was not affected by the treatments (P>0.05). Pigs that were fed with the PFAs had 3.6% higher final body weight (P=0.017) compared to the negative control. The inclusion of the PFAs reduced ammonia emissions per animal per day (P=0.003) as well as per kg body weight gain of pigs (P<0.001) on average by 21% and 26%, respectively, and tended to reduce carbon dioxide emissions per kg body weight gain (P=0.092) on average by 9% compared to the negative control. Methane and nitrous gas emissions were not affected by the inclusion of the PFAs (P>0.05).In summary, it might be speculated that the observed increased intake and consequently higher growth was mediated via flavoring properties of the PFAs, irrespective of differences in composition. The reduction of ammonia emissions most probably was due to the inclusion of the quillaja saponins in the PFAs. It can be concluded that the tested PFAs have a potential as performance enhancers and are useful tools for the reduction of ammonia emissions from pig barns. Further research is warranted to identify the exact modes of action of PFAs.

Manure, biogas digestate and crop residue management affects methane gas emissions from rice paddy fields on Vietnamese smallholder livestock farms

Greenhouse gas (CH4 and N2O) emissions from rice paddy fields amended by differently treated manure and crop residue inputs [fresh manure (FM), composted manure (CM), liquid biogas digestate from manure (D), D mixed with biochar (D + B) or D mixed with rice straw and composted before application (CD + RS)], were compared in a field experiment, also including two mineral nitrogen fertiliser controls (N1, N2). The trial was performed on a degraded soil in Bac Giang Province in northern Vietnam with a three-crop per year rotation (summer rice–maize–spring rice). CH4 and N2O fluxes from the two rice crops were measured using static chambers. Fluxes of N2O were below or close to the detection limit at nearly all sampling times in both seasons and therefore considered negligible. However, the CH4 emissions were significant and their temporal pattern differed markedly between the rice seasons. In the summer rice season, the D + B + N1 and D + N1 treatments had significantly lower cumulative CH4 emissions (156 and 162 kg CH4 ha−1 crop−1) than CM + N1, CD + RS + N1 and FM + N1 treatments (217, 283 and 288 kg CH4 ha−1 crop−1, respectively). In the spring rice season, CH4 emissions were generally much lower, and the D + B + N1 and D + N1 treatments emitted significantly less CH4 (44 and 72 kg CH4 ha−1 crop−1) in comparison with treatments amended with FM + N1, CD + RS + N1 and CM + N1 (89, 124 and 137 kg CH4 ha−1 crop−1, respectively). Treatments amended with D + B + N1 or D + N1 therefore had the lowest emissions of methane per unit of rice grain yield.

English

An integrated farming system is one of the alternatives for climatic change mitigation. This paper reports the application of corn-cattle based integrated farming system in Agrotechno Park Center of Palembang, and discusses its impact on CO 2 fixation and the reduction of methane emissions. The study was based on the data of the first 6 yr from 2003 until 2009. The CO 2 fixed in the soil and plants was determined based on the content of organic C which was multiplied by the index of 3.67. The methane gas produced by Balinese cattle and its dung was observed and modified into feed rations. The results showed that soil organic C increased from 40.80 tons C/ha in the 1 st yr to 66.40 tons C/ha in the 6 th yr. In addition, there was organic C fixation equivalent to 93.95 tons of CO 2 e. Corn biomass increased from 6.67 tons/ha to 18.66 tons/ha, equivalent to an increase in the fixation of atmospheric CO 2 e as much as 19.80 tons CO 2 e/ha. The supplementation of 60%-80% grass fodder with concentrate lowered the concentration of methane gas in cattle breathing by 28.7%, from 617 ppm to 440 ppm, while the methane emissions from cattle manure decreased by 31%, from 1367 mL/head/d to 943 mL/head/d. Installing a bio digester that generates biogas served to accommodate methane gas emissions from cattle dung and used it for bioenergy. Composting reduced the formation of methane gas from cattle manure through a regular process of turning over that gives aeration and forms aerobic condition in the heap of cattle dung. Recycling produces a variety of organic products that store carbon for a longer period of time and slowed the conversion of organic C into CO 2 . This study showed that the diverse activities of an integrated crop-cattle farming could be an alternative solution to climatic change mitigation. Key words: integrated farming, mitigation, organic C, methane, recycling

Rice Fields Mapping in Fragmented Area Using Multi-Temporal HJ-1A/B CCD Images

Rice is one of the most important crops in the world; meanwhile, the rice field is also an important contributor to greenhouse gas methane emission. Therefore, it is important to get an accurate estimation of rice acreage for both food production and climate change related studies. The eastern plain region is one of the major single-cropped rice (SCR) growing areas in China. Subjected to the topography and intensified human activities, the rice fields are generally fragmented and irregular. How remote sensing can meet this challenge to accurately estimate the acreage of the rice in this region using medium-resolution imagery is the topic of this study. In this study, the applicability of the Chinese HJ-1A/B satellites and a two-band enhanced vegetation index (EVI2) was investigated. Field campaigns were carried out during the rice growing season and ground-truth data were collected for classification accuracy assessments in 2012. A stepwise classification strategy utilizing the EVI2 signatures during key phenology stages, i.e., the transplanting and the vegetative to reproductive transition phases, of the SCR was proposed, and the overall classification accuracy was 91.7%. The influence of the mixed pixel and boundary effects to classification accuracy was also investigated. This work demonstrates that the Chinese HJ-1A/B data are suitable data source to estimating SCR cropping area under complex land cover composition.

Solid Waste Landfills as Carbon Sinks for Sequestration of Greenhouse Gases and Curtailment of Climate Change Phenomenon

This paper concentrates on studying, analyzing and assessing the potential effects of Municipal Solid Waste Management (MSWM) on Climate Change (CC). The study was carried out through conducting a Greenhouse Gas )GHG( inventory, and calculating the past and future Methane Gas (CH4) emissions generated from Askar Landfill in Bahrain. The work was based on a methodology established by the U.S. Environmental Protection Agency )USEPA( as well as an approach adopted by the Intergovernmental Panel on Climate Change )IPCC( to determine the amounts of methane gas that can be generated from MSWM; and therefore to estimate, under different scenarios, the net amounts of methane gas sequestered and emitted from the landfill into the atmosphere. Specifically, the research approach, aimed at quantifying GHG emanating from Askar Landfill )whether released from or stored within the site( during the period 2000-2020. Also it aims at investigating the possibility of converting MSW from being a source of GHG emissions with adverse CC impacts to being a carbon sink to claim emissions reduction credits through proper management of such wastes. The amounts of biochemically biodegradable organic matter contained naturally within MSW were estimated throughout the study period, incorporating available data and future forecasts. The volume of methane gas emanating from Askar Landfill had reached 25 million m3 in 2000 of a total mass estimated at 18 thousand tons or 106 thousand tons MTCE )Metric Tons Carbon Equivalent(, of which 10 thousand tons MTCE were detained within the landfill while about 95 thousand tons MTCE emitted into the atmosphere. Such quantities of generated methane gas have increased in the year 2008 to reach about 98 million m3 in volume and 69 thousand tons in mass )i.e., equivalent to 408 thousand tons MTCE(, of which more than 40 thousand tons MTCE were sequestered within the landfill and 370 thousand tons MTCE discharged up to the outer atmosphere. In the Year 2020 )at the end of the landfill’s design-life(, considering population growth and MSW increase in Bahrain, the cumulative amounts of GHG predicted from Askar Landfill in terms of methane gas generation is anticipated to stretch up to 1975 million m3 in volume and 8.3 million tons MTCE, of which 820 thousand tons MTCE is to be seized within the landfill and about 7.5 million tons MTCE is likely emit into the atmosphere, i.e., this is total over the entire 20 years period of landfill operation. From the above, it is clear that MSW sanitary landfills, though considered as significant sources of GHG emissions )particularly methane( contributing to global warming, are at the same time carbon storage vaults of some fractions of GHG resulting from the decomposing MSW mass as well as of the recalcitrant organic portions. The potential of carbon storage and sequestration at MSW landfills can be estimated at about 10 - 15% of the total quantity of biogas generated. As a result, the well- designed and operated landfills form carbon sinks and natural depots for GHG, positively impacting the climate change phenomenon. They can also be utilized to gain )and trade( credits from carbon emissions reduction in order to secure additional financial resources to help funding integrated wastes management systems.

Problems of Mechanized Tunneling In Gassy Ground Conditions a Case Study: Nousoud Water Transmission Tunnel

Current advances in science, followed by development of excavation equipments technology resulted in growth of tunnelling projects for different purposes. In spite of conducting exploratory studies prior to these projects, in some cases due to of impassable paths, the studies are limited to certain areas. Hence, during geotechnical studies, it is possible that all problems facing tunnelling not be detected. Therefore, lack of awareness of these conditions can result in a lack of proper planning and consequently lead to problems during the projects. Due to the lack of knowledge and consequently not predicting and planning the projects, drilling of the second sector of Nousoud water transmission tunnel, -26 km long- has been faced with many problems including emission of hydrogen sulfide and methane gas and drainage of high volumes of water containing dissolved gas into the tunnel, which has led to the loss of life, loss of working efficiency, as well as increased project costs. In this study, problems occurred in this project, reasons behind them will be addressed; and the solutions to these problems will be mentioned. The results of the study have shown that oil-bearing formations of the region and the immigration of gases coming from these formations have let the gas entered into the tunnel. In addition, due to the high solubility of hydrogen sulfide and methane gas in water on one hand, and hydrated formations with high permeability on the other hand, caused the influx of large quantities of water and therefore the concentration of these gases in the tunnel.

Agronomic and Ecological Evaluation on Growing Water-Saving and Drought-Resistant Rice (Oryza sativa L.) Through Drip Irrigation

A field demonstration trial comparing the growth status, yield ability and water use efficiency of drought-tolerant rice (Oryza sativa L.) varieties and normal paddy rice variety under drip irrigation and paddy irrigation was carried out for two years in Shanghai, China. Under drip irrigation, both inbred and hybrid water-saving and drought resistant rice (WDR) varieties showed better yield capacity than paddy rice varieties tested. WDR varieties under drip irrigation attained more than 95% of the yield level that is achieved in paddy field, while the paddy varieties under the same drip condition reached only about 75%.The methane gas emission was obviously decreased under drip irrigation condition, while the emission of other greenhouse gas like nitrous oxide or carbon dioxide was not observed significant difference between drip and paddy irrigation. It could be concluded that it is practicable to grow water saving and drought resistant rice through drip irrigation. Drip irrigation maintained a competitive grain yield and water productivity, and greatly reduced pollution risk to the environment. Considering the conservative amount of fertilizer application, less than the amount of fertilization in normal paddy field, the yield potential of rice could be improved by increasing the amount of fertilizer as top application in drip irrigation system.

Methanogenic community changes, and emissions of methane and other gases, during storage of acidified and untreated pig slurry

Acidification with concentrated H(2)SO(4) is a novel strategy to reduce NH(3) emissions from livestock slurry. It was recently found that also CH(4) emissions from acidified slurry are reduced. This study investigated the microbiological basis and temporal stability of these effects. Pig slurry from two farms, acidified by different techniques or untreated, was stored for 83 days in a pilot-scale facility. Methanogens were characterized before and after storage by T-RFLP and qPCR targeting mcrA. Emissions of NH(3) and CH(4) during storage were quantified. Acidified slurry pH was nearly constant at values of 5·5 and 6·5. Ammonia losses were reduced by 84 and 49%, respectively, while CH(4) emission with both acidification techniques was reduced by >90%. T-RFLP fingerprints showed little effect of acidification or storage time. A major T-RF of 105 bp could represent methanogens related to Thermoplasmata (Tp). No treatment effects on gene copy numbers were seen with universal methanogen primers, whereas effects were found with Tp-specific primers. Methane emissions were reduced >90% during storage. Thermoplasmata-related methanogens could be involved in CH(4) emissions from pig slurry. The effect of acidification on CH(4) emissions during storage of pig slurry was quantified for the first time. Acidification with sulphuric acid holds promise as a novel greenhouse gas mitigation strategy for confined livestock production.

CFD Modeling of Methane Gas Distribution and Control Strategies in a Gassy Coal Mine

High methane (CH4) gas emission from the goaf in a gassy coal mine diffuses the gas into the face that leads to hazardous working environment and create operational difficulties. Electrical equipment which are loaded with sensors get tripped off when CH4 level is greater than 2%. Oxygen (O2) ingresses more on the maingate (MG) side than the tailgate (TG) side of the goaf due to high ventilation air pressure and hence no major gas issues are dealt on this side of the goaf. However, when the air flows along the face, air pressure decreases and less O2 ingress on TG side of goaf and more CH4 gas diffuse into the face in these regions. CH4 gas diffusion not only disrupts the functioning of electrical equipment but also creates hazardous environment for the operator. In this paper, an attempt was made to understand the CH4 gas distribution at the TG for gas emission rate of 1000l/s respectively and investigate the control options available for diluting the gas concentrations in the TG region. From Computational Fluid Dynamics (CFD) investigations, it was concluded that for gas emission rates over 1000l/s the CH4 concentration level at the TG region was above 2% and demand for control measures. Gas control strategies with goaf drainage, back return ventilation system and curtains across the face in the TG region were investigated using CFD techniques. From numerical investigations, it can be concluded that gas control strategy with goaf drainage was able to reduce the CH4 level to below 1% and back return system at the TG side was able to completely eliminate gas traces. Placing a curtain assisted in shifting the gas fringes into the goaf and thereby reducing the gas concentrations to below 1%.

Determination of Tannin Content in Various Parts of Six Citrus Species

Tannin content of roots, stems, stem barks, leaves and peels of six species of Citrus was investigated. They include Citrus aurantifolia (Christm.) Swingle (Lime), C. grandis Osbeck (Shaddock/Pummelo), C. limon (L.) Burm. f.(Lemon), C. paradisii Macf. (Grapefruit), C. reticulata Blanco (Mandarin/Tangerine) and C. sinensis (L.) Osbeck (Sweet orange). The study showed that tannin was present in all parts of these Citrus species. The highest level of tannin was contained in the leaves of C. aurantifolia [1.44±0.02%] and C. limon [1.30±0.02%] respectively; whereas the least concentrations were found in the roots of C. reticulata [0.06±0.02%] and C. sinensis [0.08±0.04%] respectively. The roots, stems, stems barks, leaves and peels extracts of these Citrus species could be employed in ethnomedicine as drugs, due to the therapeutic values of tannin. In addition, they could be regarded as potential rich sources of natural tannin which could be isolated and utilized in cosmetic industry as antimicrobial agents, pharmaceutical industries for production of drugs, agriculture for reduction of emission of methane gas from ruminants, tannery industry for manufacture of leather, as additives in wine production to ameliorate the astringency and in manufacture of adhesives.

Suppression of Methane Gas Emissions and Analysis of the Electrode Microbial Community in a Sediment-Based Bio-Electrochemical System

The effects of bioelectrochemical systems (BESs) for the suppression of methane gas emissions from sediment were examined using a laboratory-scale reactor system. Methane gas emissions from acetate were suppressed by approximately 36% from control based on the installation of a BES in which carbon-graphite electrodes were buried in sediment and arbitrarily set at certain oxidative potentials (+300 mV vs Ag/AgCl) using a potentiostat. Meanwhile, methane gas emissions increased in the BES reactor where the electrode potential was set at -200 mV. Results obtained from pyrotag sequencing analysis of the microbial community on the surface of the buried electrodes targeting 16S rRNA genes demonstrated that the genusGeobacterhad drastically propagated in a sample from the reactor where the electrodes were buried. Quantitative analysis of 16S rRNA genes of archaea also revealed that the archaeal population had decreased to approximately 1/6 of its original level on the electrode of the BES set at +300 mV. This implied that the oxidation-reduction potential (ORP) in the sediment was raised to the inhibition level for methanogenesis in the vicinity of the buried electrode. Analysis of electron flux in the experiment revealed that electrons intrinsically used for methanogenesis were recovered via current generation in the sediment where a potential of +300 mV was set for the electrode, although most electrons donated from acetate were captured by oxygen respiration and other electron-accepting reactions. These results imply that BES technology is suitable for use as a tool for controlling re-dox-dependent reactions in natural environments, and that it also brought about changes in the microbial population structure and methanogenic activity in sediment.

Predicted Wildlife Disease-Related Climate Change Impacts of Specific Concern to USDA APHIS Wildlife Services

USDA APHIS Wildlife Services plans for and responds to a variety of exigencies such as wildlife hazards to aircraft, disease emergence from wildlife translocations, oral rabies vaccine barrier compromises, and extreme weather events. These are often collaborative efforts with state and federal agencies and others. Climate change based in part on fossil fuel use and methane gas emissions has predictable as well as unknown consequences. As a federal leader in wildlife disease research and management, it is incumbent upon Wildlife Services to be current with the scientific literature; assess potential impacts and wildlife disease management intervention needs from predicted climate change scenarios; and outline a plan of preparedness to meet a variety of potential exigencies. KEY W ORDS : climate change, disease, epizootic, USDA Wildlife Services, vector-borne disease, zoonotic disease Proc. 26 th Vertebr. Pest Conf. (R. M. Timm and J. M. O'Brien, Eds.) Published at Univ. of Calif., Davis. 2014. Pp. 310-315.

Formulating LandGem model for estimation of landfill gas under Indian scenario

Mostly in India, solid waste without any segregation is deposited into open dumping sites. Through these sites, there is uncontrolled emission of methane and landfill gas. The landfill gas has tremendous potential in terms of converting and using them as source of fuel. The emission of landfill gas depends on types of wastes, its rate of biodegradability, its methane potential, level of segregation and many more. In order to estimate the level of landfill gas emission, there are various US EPA recommended models are available. One of them is LandGem. But this model has been derived as per the US climatic conditions and their type of waste. It is needed to be converted into Indian conditions before applying it for Indian landfill site. This paper formulates the criteria required for converting the LandGem equation as per Indian condition and using it for Indian landfill sites. The model is verified with its application for two landfills sites of Mumbai, Deonar and Mulund.

Methane-oxygen electrochemical coupling in an ionic liquid: a robust sensor for simultaneous quantification.

Current sensor devices for the detection of methane or natural gas emission are either expensive and have high power requirements or fail to provide a rapid response. This report describes an electrochemical methane sensor utilizing a non-volatile and conductive pyrrolidinium-based ionic liquid (IL) electrolyte and an innovative internal standard method for methane and oxygen dual-gas detection with high sensitivity, selectivity, and stability. At a platinum electrode in bis(trifluoromethylsulfonyl)imide (NTf2)-based ILs, methane is electro-oxidized to produce CO2 and water when an oxygen reduction process is included. The in situ generated CO2 arising from methane oxidation was shown to provide an excellent internal standard for quantification of the electrochemical oxygen sensor signal. The simultaneous quantification of both methane and oxygen in real time strengthens the reliability of the measurements by cross-validation of two ambient gases occurring within a single sample matrix and allows for the elimination of several types of random and systematic errors in the detection. We have also validated this IL-based methane sensor employing both conventional solid macroelectrodes and flexible microfabricated electrodes using single- and double-potential step chronoamperometry.

Preliminary study of methane oxidation in landfill cover soil: The effect of moisture content

Methane oxidation is one of the important processes to mitigate the emission of methane gas at landfill to the environment. Th is study investigated the effect of moisture content in order to enhance the methane oxidation of final cover soil fro m Taman Medan Du mpsite. Three different PVC soil colu mns contained cover soils with mo isture content of 7%, 12% and 28% were used in this study. The columns were purged with the mixture of methane gas (60% by volume) and carbon dio xide gas (40% by volume) fro m the bottom of the soil co lu mn s. The mixture gas passing through the soil med ia was retrieved fro m the colu mns daily via sampling ports fabricated at every 10cm of the column height. The soil cover was classified as sandy silt contained 56 % of sand, 32 % of silt and 12 % of clay. It also had 12% of mo isture content, bulk density of 0.229 g/cm3, particle bulk density of 0.0304 g/cm3, pH of 7.21, colour of dark yellowish brown, porosity of 86.72% and organic matter of 1.5 %. Gas chromatography analysed the collected gas had showed that methane oxidation effectively occurred in the colu mn with 12% of mo isture content that the average methane oxidation efficiency of the 7 -day experiment was 47.97%. Ho wever, the methane oxidation efficiency in the other two columns with 7 and 28% of moisture content was significantly lower with only 8.93 and 7.87% of efficiency. The analyses also showed highest methane oxidation efficiency, by average, took place at the height of 80cm of those columns.