Tercer Seminario regional agricultura y cambio climático: nuevas tecnologías en la mitigación y adaptación de la agricultura al cambio climático
Arqueas metanógenas en al mitigación del cambio climático en la agricultura
Flávia Talarico Saia Chemistry Institute, Universidade Estadual Paulista Júlio de Mesquita Filho – UNESP, Araraquara, SP, Brazil Email:
[email protected] 1
CH4 as a source of energy
Intergovernmental pane l on climate change (IPCC), 2007
METHANE
19th century anthropogenic
Anaerobic treatment of waste Methane concentration in the atmosphere
CH4
Recovered and used clean Fonte: NASA/Goddardas Space Flightenergy Center
Methane to Market
CH4 as a greenhouse gas Methane has global warming potential (GWP) 21-25 times more than CO2
Methane accounts for about 20% of global warming 2
• Mitigation strategies for methane emissions • Use of methane as a energy source
• Sources of methane emission • Methanogenic microorganisms 3
THEY ARE THE ONLY MICROORGANISMS KNOWN THAT PRODUCE METHANE
Methanogenesis: The Process Anaerobic condition
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multi-step process carried out by different groups of microorganisms 1. Hydrolytic Bacteria 2. Fermentative Bacteria 3. Acetogenic Bacteria 4. Methanogenic Archaea
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Hydrogenotrophic H2, formate
Acetoclastic Acetate
Methanobrevibacter
Methanosaeta
Methilotrophic Methanol Methanosarcina
• It is important for carbon cycle since methanogenesis prevents a build-up of organic matter, allowing the other microorganisms to support the oxidation of substrates
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Hydroeletric
Rice fields
wetlands
Landfill WHERE ARE METHANOGENIC ARCHAEA ? Methanogens are ubiquitous in anoxic environments
Anaerobic digesters
Livestock - cattle
Termites
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Agriculture - source of methane Major sources of methane emissions: • Agriculture : In 2010 accounted for 53% of global methane emission • Energy: oil and natural gas systems • Waste: solid waste and wastewater treatment
Yusulf et al. (2012) Renewable and Sustainable Energy Reviews
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Agriculture sectors
• Manure: stored or treated in liquid system - Top emmiting counties: U.S., Germany, India, China, France, Russia, Turkey and Brazil.
Yusulf et al. (2012) Renewable and Sustenaible Energy Reviews
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Agriculture - CH4 emissions in Brazil
Agriculture sectors glogster.com
Other sectors 4% Coal mining 8%
Enteric Fementation 22%
Manure Management 7%
Biomass 11% Landfills 10%
Wastewater Treatment 7%
greencleanguide.com
Agriculture accounting for 45% of CH4 emission
Rice cultivation 16%
novotempo.com
Oil gas 15%
Largest beef exporter in the world
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Vinasse – liquid waste from ethanol Sugarcane
Ethanol
Vinasse
Vinasse has been used as fertilizer to sugarcane fields •Emission of methane during storage of vinasse • Emission of N2O from soil Brazil is the largest producer of sugarcane ethanol in the world and immense volume of vinasse is generated – 10L vinasse/L ethanol In 2006/2007, 190 billions of liters of vinasse were produced Rego e Hernández (2006); Oliveira (2011); Carmo et al., 2012
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Brazilian authorities announced that the country will target a reduction in its GHG between 36.1 and 38.9% from projected 2020 levels.
The Intergovernmental Panel on Climate Change - IPCC (2007)
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Mitigation Strategies: Enteric Fermentation • CH4 is not only GHG but it is also a waste of fed energy for the animal •Large number of MA are in the ruminal liquid: 107 to 109 cells/mL (Kamra, 2005).
Hydrogenotrophic methanogens: Methanobacteriales, Methanomicrobiales, Methanosarcinales have been found
Methanobrevibacter smithii
Methanobacterium formicicum
Methanosarcina barkeri
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microbewiki
Enteric Fermentation – mitigation strategies (MS) to methane emission MS target the methanogens of the rumen directly or indirectly • Diet Composition: use of easy degradable carbohydrate – reduce pH in the rumen – decreases MA. However, accumulation of organic acids can occur, leading to subacute ruminal acidosis (SARA) and disruption of the rumen microbiota (Plaizier et al., 2008). • Lipids: Fatty acids and oils (Johnson and Johnson, 1995; Hook et al., 2010). - inhibition of protozoa which supply methanogens with hydrogen - Increase the production of propionic acid - it is not used for methanogens - Binding to the cell membrane of methanogens and interrupting membrane transport • Defaunation: decrease the number of protozoa by the use of copper, sulphate, acids, (Hook et al., 2010) • Vaccines: target methanogens directly (Wedlock et al., 2010) Hook et al. (2010)
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Enteric Fermentation – mitigation strategies (MS) to methane emission • Other strategies: selection of high quality grasses, increase grain level and
increasing feed conversion efficiency to produce meat and milk Researches have shown:
• MS are limited by the diet feed, the management conditions, physiological condition, use of the animal, and government laws. • Long-term experiments in vivo need to be done to implement MS
• Economic viability of the producer needs to be addressed Brazil: diversty of methahogens related with diet – hay proportions (Neves et al., 2010) improvement of meat production related with sugarcane feeding in dry season (Primavesi et al., 2003)
Hook et al. (2010); Yusuf et al., 2012
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Rice fields CH4 is produced by anaerobic degradation of organic matter that occurs in soil and also in roots CH4 oxidation by methanotrophic bacteria
Anaerobic CH4 oxidation
www1.ethz.ch
MS = net methane emission Phillipot et al. (2009), Dubey (2005)
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• Acetoclastic but mainly hydrogenotrofic methanogens Methanolinea
Methanobacterium kanagiense
Sakai et al., 2012
Kitamura et al., 2011
Methanoculleus chikugoensis
Dianou et al., 2011
• Methanotrophic bacteria Methylomonas koyamae sp Adachi et al 2001
Methylosinus
Ogiso et al., 2011
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Mitigation Strategies: Rice field • Mitigation strategies include: - reduction of methane production; increasing methane oxidation, lowering methane transport through the plant • Selection of cultivars with low exudation rates • To keep the soil as dry as possible in the off- rice season : adverse environmental condition for methanogenesis
• Use of fertilizer: ammonium nitrate and sulphate instead of urea
Current information is insufficient for the development of technology and strategy for reduction in methane emission
To improve the knowldgement of methanogens and methanotrophic bacteria in soil and in roots
Phillipot et al. (2009), Dubey (2005) 18
Mitigation Strategy: anaerobic treatment of manure and vinasse
Aim: to apply anaerobic technology to PRODUCE METHANE for BIOENERGY PURPOSES
Land applications (N, K, P) pathogenic microorganisms
Methane has a high energy value (ΔHo= 816 kJ/mol or 102 kJ/e- eq) that can be captured through combustion and used for space heating or eletricity
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• Studies
have been carried out to better understand the anaerobic process in order to control the process and achieve optimum biogas yield Support medium
Configuration of reactors UASB
Polyhurethane foam HAIB
• Effect of inhibitory substances: ammounium, salt content, sulphate, temperature
Lettinga (1980)
Foresti et al. (1995)
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Microorganisms – biodigestors treating manure slurries • Methanosarcinaceae and Methanobacteriales are predominant in anaerobic reactors treating different kinds of manure • Due to high levels of ammonium, pointig out the importance of hydrogenotrophic methanogenesis (Netmman et al., 2010) Methanosarcina
Methanomicrobium
Methanobrevibacter
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Microorganisms – biodigestors treating vinasse • Acetoclastic and hydrogenothrophic methanogens Methanosarcina
microbewiki
Methanomicrobium sp
bacmap.wishartlab.com
Methanosaeta
Araújo et al. (2003)
• Termophilic process – vinasse is produced at high temperatures (80-900C) Souza et al. (1992); Viana (2006); Ribas (2006) - sludge stable among harvests - It is necessary to decrease temperature - process is faster than mesophilic
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Hydrogen and methane production Use of two -stage bioreactors to produce hydrogen and methane
Vinasse
Acidogenic reactor
H2 and acids production
Peixoto et al. (2012)
Methanogenic reactor
Consumption of acids and production of methane
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Conclusions Emissions of methane from agriculture activities are a
worlwide problem, mainly regarding enteric fermentation, rice field and manure managment In Brazil: contribution of vinasse used as fertilizer
Studies have shown that there are mitigation strategies, however a better understanding of the microorganisms, the factors affecting symbiotic relation with other microbial population and their environment, also long term expriments are needed to implement MS 24
Brazil • Studies focused on microbial diversity: Amazon and Pantanal
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Muchas gracias Flávia Talarico Saia
[email protected] 55 16 33019506 26
