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Greenhouse gas mitigation in agriculture Issue | Volume 363, Number 1492 / February 27, 2008 | Editor(s) | Chris Pollock Jules Pretty Ian Crute Chris Leaver Howard Dalton
| Pages | 789-813 | Issue Title | Theme Issue ‘Sustainable agriculture II’ compiled by Chris Pollock, Jules Pretty, Ian Crute, Chris Leaver and Howard Dalton | DOI | 10.1098/rstb.2007.2184 | |
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Authors
Pete Smith1,
Daniel Martino2,
Zucong Cai3,
Daniel Gwary4,
Henry Janzen5,
Pushpam Kumar6,
Bruce McCarl7,
Stephen Ogle8,
Frank O'Mara9,
Charles Rice10,
Bob Scholes11,
Oleg Sirotenko12,
Mark Howden13,
Tim McAllister5,
Genxing Pan14,
Vladimir Romanenkov15,
Uwe Schneider16,
Sirintornthep Towprayoon17,
Martin Wattenbach1,
Jo Smith1 1School of Biological Sciences, University of Aberdeen, Aberdeen AB24 3UU, UK
2Carbosur, Constituyente 1467/1202, Montevideo 11100, Uruguay
3Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China
4University of Maiduguri, Maiduguri, Borno State 1069, Nigeria
5 Agriculture and Agri-Food Canada, Research Centre, Lethbridge, Alberta, Canada T1J 4B1
6Institute of Economic Growth, University Enclave, Delhi 110 007, India
7Department of Agricultural Economics, Texas A&M University, College Station, TX 77843, USA
8NREL, Colorado State University, Fort Collins, CO 80523, USA
9School of Agriculture, Food Science and Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
10Department of Agronomy, Kansas State University, Manhattan, KS 66506, USA
11CSIR Division of Water, Environment and Forest Technology, Pretoria 0001, Republic of South Africa
12 All-Russian Institute of Agricultural Meteorology, Obninsk, Kaluga Region 249020, Russia
13 CSIRO Sustainable Ecosystems, GPO Box 284, Canberra, Australian Capital Territory 2601, Australia
14College of Resources and Environment Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
15 Pryanishnikov All-Russian Institute of Agrochemistry (VNIIA), 127550 Moscow, Russia
16Departments of Geosciences and Economics, Hamburg University, 20146 Hamburg, Germany
17The Joint Graduate School of Energy and Environment, King Monkut's University of Technology, Thonburi, Bangmod, Bangkok 10140, Thailand
Abstract
Agricultural lands occupy 37% of the earth's land surface. Agriculture accounts for 52 and 84% of global anthropogenic methane and nitrous oxide emissions. Agricultural soils may also act as a sink or source for CO2, but the net flux is small. Many agricultural practices can potentially mitigate greenhouse gas (GHG) emissions, the most prominent of which are improved cropland and grazing land management and restoration of degraded lands and cultivated organic soils. Lower, but still significant mitigation potential is provided by water and rice management, set-aside, land use change and agroforestry, livestock management and manure management. The global technical mitigation potential from agriculture (excluding fossil fuel offsets from biomass) by 2030, considering all gases, is estimated to be approximately 5500–6000Mt CO2-eq.yr−1, with economic potentials of approximately 1500–1600, 2500–2700 and 4000–4300Mt CO2-eq.yr−1 at carbon prices of up to 20, up to 50 and up to 100 USt CO < sub > 2 < /sub > -eq. < sup > -1 < /sup > , respectively. In addition, GHG emissions could be reduced by substitution of fossil fuels for energy production by agricultural feedstocks (e.g. crop residues, dung and dedicated energy crops). The economic mitigation potential of biomass energy from agriculture is estimated to be 640, 2240 and 16 000Mt CO < sub > 2 < /sub > -eq.yr < sup > -1 < /sup > at 0–20, 0–50 and 0–100 US t CO2-eq.−1, respectively.
Keywords
greenhouse gas, agriculture, mitigation, cropland management, grazing land, soil carbon
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