Soil carbon stock changes and GHG emissions preliminary results

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2 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

3 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

4 Origin of soil carbon? Soil carbon

5 Soil carbon stocks 100 cm 100 cm 10 cm S = C content X d X layer % C d = m V 10 cm kg C m -2 or Mg C ha -1

6 Soil density calculation d = m v Mass of soil contained in a cilinder = m Volume of the cilinder = v

7 Quantification of soil carbon content CN-2000 Results = % C and % N

8 Soil carbon dynamics Global warming GHG CO 2,N 2 O, CH 4 Soil carbon DEFORESTATION Time

9 Soil carbon dynamics Global warming CO 2 Photosynthesis Conservationist agricultural system Soil carbon Carbon introduced by crop litter DEFORESTATION Time

10 Sugarcane harvest with burning

11 Stock changes in the sugarcane agrosystem Carbon introduced d } by the crop }? Soil carbon remaining from forest }? DEFORESTATION t Time

12 ORIGIN OF SOIL CARBON CHANGE IN PLANT COVER Carbon introduced by the crop SINGLE ORIGIN TWO ORIGINS Carbon remaining from forest

13 P R I N C I P L E C3 CO 2 = -7.5 CONVERSION C4 13 C = C = -12 } Solo C Total C Total Cc 13 C Soil under forest 13 C Soil under crops Csoil = Cf + Cc t 0 TIME DILUIÇÃO Csoil. 13 Csoil ISOTÓPICA = Cf. 13 Cf DO + Cc 13 C. NO 13 CcSOLO } Cf

14 SUGARCANE AGROSYSTEM NATIVE FOREST (C3) SUGARCANE (C4) 13 C = C = YEARS 50 YEARS 13 Csoil = ENRICHMENT IN CARBON 13 Cerri et al., 1985

15 NATIVE FOREST (C3) 13 C = -29 SUGARCANE (C4) 13 C = YEARS 50 YEARS 8-2 ) Carbon (kg.m - 4 CARBON INTRODUCED BY THE CROP (ROOTS) 0 CARBONO TOTAL E 13 C CARBON REMANING NG FROM FOREST years

16 Mechanized unburned sugarcane harvest

17 Transference of carbon from litter to soil and atmosphere Emission i as CO 2 Litter layer l (trash) Soil Organic Carbon input

18 Stock changes under sugarcane Native vegetation Burned sugarcane So oil carbon (kg.m -2 ) CARBON REMAINING FROM FOREST Change in management years

19 Stock changes under sugarcane CO 2 Native vegetation Burned sugarcane Cana-de-açúcar colhida sem queima C soil carbon C litter Soil CARBON REMAINING FROM FOREST Change in management

20 Soil carbon stocks after 3 years of unburned management Burned Unburned Mg gc ha Burned Unburned Mg C ha Latossolo Vermelho Argiloso (0-10 cm) Neossolo Quartzarênico Arenoso Lucca (2002)

21 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

22 Carbon footprint of ethanol CO 2 eq CO 2 PHOTOSYNTHESIS N 2 O CO 2 CH 4 CO 2 CH 4 N 2 O CO 2 CH 4 CH 4 FERTIRRIGATION VINASSE Soil Carbon PLANTING MANAGEMENT HARVEST N 2 O CO 2 CH 4 CO 2 N 2 O CH 4 BAGASSE SOLID RESIDUES PLANT ELECTRICITY COMPOSTED FILTER CAKE TRANSPORT

23 Field sampling of gases T 1 Lid Base Incubation chamber T 2 T 3... T n Hermetic seringes for gas collection o

24 Cromatographic analysis of GHG Detectors: Electron Capture Detector CO 2 e N 2 O Flame Ionization Detector CH 4 T0 T5 T10 Cerri T20 (2009)

25 Gas flux calculation (CO 2, N 2 O and CH 4 ) Cromatogram a = gas concentration in the sample [ppm] tration s concent Ga T0 T5 T10 T20 min Incubation time Angular coefficient = Gas flux

26 Measuring soil gas emissions under sugarcane

27 Soil GHG emissions from residues and fertilizers Soil and litter GHG emissions Fertilizer N 2 O emissions

28 GHG Emissions N 2 O fluxes µg N 2 O m -2 h -2 Harvest burned unburned 0-50 August November March May Jully Avg -100 µg CH 4 m -2 h CH 4 Fluxes August November March May July Avg

29 On-site analyses Portable chromatograph

30 Sampling of methane emitted by vinasse

31 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

32 Site location GOIANA TIMBAÚBA TULLY MACKAY PRADÓPOLIS MOUNT EDGECOMBE HARWOOD

33 Soil carbon dynamics in the sugarcane agroecosystem Time Depth

34 CENTURY model CLIMATE CROP SOIL

35 Model parameterization Harv.100 GCANE 0.01 'AGLREM' 0.10 'BGLREM' 0.0 'FLGHRV' 0.64 'RMVSTR' 0.0 'REMWSD' 0.0 'HIBG'

36 Model parameterization Fire.100 CANE 0.30 'FLFREM' 0.9 'FDFREM(1)' 0.9 'FDFREM(2)' 0.7 'FRET(1)' 0.0 'FRET(2)' 1.0 'FRET(3)' 0.2 'FRTSH' 10.0 'FNUE(1)' 'FNUE(2)

37 N inputs Atmospheric deposition (wet + dry) 28 kg N ha -1 year -1 (Bortoleto Júnior, 2004) Biological fixation Up to 200 kg N ha -1 year -1 (Dobereiner, 1997) Mineral and organic fertilization

38 Experiment in Pradópolis, São Paulo MN Replanting Years Time Depth cm

39 Chronosequence NATIVE FOREST SUGARCANE B 2 B 6 B 8 U 2 U 6 U 8

40 Areas sampled Áreas amostradas

41 Central trench m 1.5 m

42 Small trenches m m m

43 Soil carbon stocks (0-20 cm) Native forest Burned sugarcane Unburned sugarcane g m Years after replanting

44 Soil carbon stocks (0-20 cm) Corrected for density Native forest Burned sugarcane Unburned sugarcane g m Yeas after replanting

45 Litter decomposition Atmosphere Fresh litter Soil

46 Litter decomposition Atmosphere Fresh litter Pool 1 Pool 2 Soil

47 Litter decomposition Measured carbon Simulated carbon CENTURY Mackay (precoce) Mackay (tardia) Tully Carbo ono (gm -2 ) Dias após a colheita Carbo ono (gm -2 ) Dias após a colheita Carbo ono (gm -2 ) Dias após a colheita Harwood (precoce) Harwood (tardia) Goiana Carbo ono (gm -2 ) Carbo ono (gm -2 ) Carbo ono (gm -2 ) Dias após a colheita Dias após a colheita Dias após a colheita Pradópolis Carbon no (gm -2 ) Dias após a colheita

48 Litter decomposition Measured carbon Simulated carbon CENTURY Simulated carbon CENTURY (modified) Mackay (precoce) Mackay (tardia) Tully Carbo ono (gm -2 ) Dias após a colheita Carbo ono (gm -2 ) Dias após a colheita Carbo ono (gm -2 ) Dias após a colheita Harwood (precoce) Harwood (tardia) Goiana Carbo ono (gm -2 ) Carbo ono (gm -2 ) Carbo ono (gm -2 ) Dias após a colheita Dias após a colheita Dias após a colheita Pradópolis Carbon no (gm -2 ) Dias após a colheita

49 Litter decomposition CENTURY CENTURY (modified)

50 Long-term simulation Soil carbon Simulated (burned) -2 C gm Goiana Anos -2 C gm Pradópolis Anos C gm Timbaúba 8000 Mount Edgecombe Anos C gm Anos

51 Long-term simulation Soil carbon Simulated (burned) Simulated (unburned) -2 C gm Goiana Anos -2 C gm Pradópolis Anos C gm Timbaúba 8000 Mount Edgecombe Anos C gm Anos

52 Soil Science Society of America Journal (2009) 73:

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54 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

55 CO 2 eq Sugarcane Plant Use Areas currently cropped

56 CO 2 eq Livestock and other crops Sugarcane Plant Use Expansion Areas currently cropped

57 CO 2 eq Livestock Sugarcane Plant Use Expansion Areas currently cropped

58 CO 2 eq Oh Other crops Sugarcane Plant Use Expansion Areas currently cropped

59 GHG emissions due to burning vegetation Above-ground biomass (t C ha -1 ) Cerradão Cerrado Campo sujo Degraded pasture ~ 5

60 OUTLINE Soil carbon: basic concepts GHG fluxes in the soil-plant-atmosphere atmosphere system Soil carbon stock changes and GHG emissions preliminary results Land use change Final considerations

61 Final considerations AGRIBUSINESS GREENHOUSE GASES C R O P S Plant Biomass ENERGY Biodiesel Ethanol Biofuel TEP OFFSET Crop residues C Decompostion Soil carbon sequestration Significant role FIXATION

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