conservation agriculture carbon offset consultation october 28 – 30, 2008 west lafayette, indiana,...

Download Conservation Agriculture Carbon Offset Consultation October 28 – 30, 2008 West Lafayette, Indiana, USA Carbon balance and sequestration in no-till soils

Post on 16-Jan-2016

213 views

Category:

Documents

0 download

Embed Size (px)

TRANSCRIPT

  • Conservation Agriculture Carbon Offset ConsultationOctober 28 30, 2008West Lafayette, Indiana, USACarbon balance and sequestration in no-till soils under intensive cropping systems in tropical agroecozonesJoo Carlos de Moraes Sand Lucien Sguy

  • Cropping Systems and C-Sequestration TeamUEPG PR, Brazil: Dr. Joo Carlos de Moraes S (Coordinator) CIRAD France: Dr. Lucien Seguy (Coordinator) and 12 researches located in Africa and AsiaGraduate Students - 07 Undergraduate Students - 14 International CollaborationThe Ohio State University: Dr. Rattan Lal

  • OutlineGeneral overview: soils characteristics and No-till in the tropicsConcept of intensive cropping systems and commentsGeneral and specific objectives MethodologySites location and descriptionDescription of cropping system and biomass inputResultsC input by biomass and conversion to SOC SOC stockC Sequestration rates by cropping systemEstimation and scenarios for C Sequestration for Brazilian Cerrado and other tropical areas Summary and conclusionsIntroduction

  • General overview

  • Main differences Tropical and Temperate soils Variable charges deprotonation of surface functional groups (pH dependent charge)Permanent charges by isomorphic substitution replacement of one atom by another of similar sizeLow natural fertilityHigh natural fertilityLow pHModerate to High pHHigh exchangeable Al3+No exchangeable Al3+Good natural drainageModerate and poor natural drainageType 1:1 Kaolinite, Iron and Aluminum oxidesType 2:1 Montmorilonite, Vermiculite, Ilite OxisolMollisol

  • AMACRRPAAPROMTMSRSSCPRSPGOMGBATOMAPICERNPBPESEALExpansion of agricultural area in BrazilTotal cropped area56 million ha

  • Expansion of No-till area in Brazil (1972 2006)

  • Methodology

  • BrazilMadagascarCambodiaTropic of CancerEquatorTropic of CapricornVietnamLaosThailandCameroonExperimental Sites

  • The meaning of the intensive cropping system comprise in to close the window between the rainy season (wet summer) and the dry season (dry winter) using cover crops and cash crops, to maintain the soil surface permanent covered. The concept of Intensive cropping system

  • The challenge in the tropics is to manage the decomposition rate of the crop residues, and keep the soil covered

  • Crop residues decomposition (oats + remaining residues) during the corn development (Pira do Sul, 910 m ASL, 25 SL, 2003-04, Oxisol (62% of clay)EquadorTropic of CapricornPira do Sul

  • Source: S, et al, 2004y = 9002 29.95xR2 = 0.98***0200040006000800010000050100150200DAE of CornDry biomass (kg/ha)29.95 kg day-1 of DMPlanting (05/10/03)FloweringPhysiological maturationHarvest (14/03/04)Crop residues decomposition (oats + remaining residues) during the corn development (Pira do Sul, 910 m ASL, 25 SL, 2003-04, Oxisol (62% of clay)9106 kg ha-1 DM = 4098 kg ha-1 C4210 kg ha-1 DM = 1985 kg ha-1 C

  • EquadorTropic of CapricornRio VerdeCrop residues decopmposition (Brachiaria decumbens) during the corn development (Rio Verde, 880 m ASL, Latitude 16 S, 2003-04, Oxisol (65% of clay)

  • Planting (19/10/03)FloweringHarvest (16/02/04)Crop residues (Brachiaria decumbens) decomposition during the corn development Rio Verde, 880 m ASL, Latitude 16 S, 2003-04, Oxisol (65% of clay)10000DAE of CornFonte: S, et al, 2004y = 8980 58.26xR2 = 0.9602000400060008000050100150DM (kg/ha)58.26 kg day-1 of DMSource: S, et al, 2004Physiological Maturation8658 kg ha-1 DM 3896 kg ha-1 C1910 kg ha-1 DM 860 kg ha-1 C

  • - 1676 kg/ha MS - 754 Kg/ha CAmount of crop residues to maintain the C equilibrium in the soilZero DMGeneral Balance = (- 3896) + (- 754) = - 4650 kg C ha-1 10.32 Mg ha-1 DM

  • Fonte: Seguy & Bouzinac, 2000Results

  • Input of 1.0 ton of crop residues0.736 ton25 SLSoil organic matter poolsLive organism0.044 Stable (0.22 ton)Humic SubstancesNo humic substances0.06 0.16 CO2Source: S et al. 2001; 2007 Distribution of the decomposition products of the crop residues in the SOM pools

  • SOC balance for 0- to 20-cm depth for experimental sites

    SiteCroppingSOC MeasuredC inputSOCSystem/Till.t1t2CumulativeAnnualSequestration rates------------------------ Mg ha-1 ---------------------Mg ha-1 yr-1CVCT-S18.1217.04 2.29 1.15-0.54MT-S/Mlt23.6620.41 7.62 3.81-1.63NT-S/Els+Crt28.4732.0518.78 9.39 1.79NT-S/Sgh+Brq30.6635.0319.38 9.69 2.18LRVCT-S48.3043.70 4.87 0.97-0.93NT-S/Els+Crt55.8065.1037.12 7.42 1.86NT-S/Sgh+Brq58.3068.8039.54 7.91 2.10SnpCT-S48.6843.70 3.67 0.92-1.25NT-S/Els+Crt40.3047.2040.1210.03 1.73NT-S/Tifton43.0253.4051.2612.82 2.60Adrom.Fallow47.3741.40 1.08 0.12-0.66Madag.NT-M/S47.3756.3816.05 1.78 1.00NT-M+SD47.3752.6925.08 2.79 0.59NT-S/GB+KK47.3756.8135.50 3.94 1.05

  • Example of Soybean/Corn + Brachiaria and Sorghum + Brachiaria rotationSoil permanent covered

  • Example: Campo Verde MTOxisol, Red Dark Latosol, Sand-ClayAnnual C input (Avg) = 9.7 Mg ha-1 (21.6 Mg ha-1 of Crop Residues)Dry seasonDry seasonDry seasonRainy seasonRainy seasonRainy season

  • Soybean harvest (3.5 to 4.0 tons of DM) FebruaryCorn and Brachiaria planting - FebruaryCorn harvest (7 tons of DM) June After harvest10 to 20 days after harvest(root system > 50 cm)Example of Soybean/Corn + Brachiaria + beef cattle rotationGrazing June, July and AugustOctoberDecember 5.5 tons of Brachiaria DMSoil permanent covered

  • Distribution of C in the particle size fraction in the profile under three crop rotations with cotton as the main crop (Campo Verde-MT, Brazil, 16 SL)

  • Cumulative C input x SOC sequestered

  • In tropical areas the challenge with cropping systems is to adjust cash crops and cover crops that can be profitable and compensate the high decomposition rates of the crop residues

  • Scenario 1 Potential of C-sequestration based in average rate Average rate of C-Sequestration0.5 Mg ha-1 yr-1(Bernoux et al. 2006; Bayer et al., 2006; Cerri et al., 2007)

  • Scenario 1

  • Scenario 2

  • Scenario 3

  • Scenario 3

  • Scenario 4

  • Scenario 4

  • In tropical areas the management of the soil organic matter through adoption of intensive cropping systems with high C input (more than 7.4 Mg C ha-1 yr-1 ), and based in the systemic approach to close the window between wet and dry season it is the main way to enhance SOC sequestration and sustainability. ConclusionsThe challenge is to convince the farmers to adopt these system in large scale.Four points to convince the farmers:

    Reduction of costs Reduction of the risks with weather impact (Drought ) Increase the yield of the main cash crop and the profitability of the whole system Making extra money with C-sequestration and giving a good contribution to the environment.

    *

Recommended

View more >