Is conservation agriculture climatesmart for maize farmers in the highlands of Tanzania?

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Is conservtion griculture climtesmrt for mize frmers in the highlnds of Tnzni? Kimro A.A., Rosenstock, T.S., Mpnd, M., Rioux, J., Shb, S., Aynekulu1, E., Krttunen, K., Neufeldt, H., nd Shepherd, K. D. World Agroforestry Centre (ICRAF) nd FAO

The MICCA Progrmme Climte Smrt prctices tht mitigte climte chnge in griculture Move towrds low crbon emissions griculture while enhncing sustinble food security, nutrition nd productivity. CA/CAWT Adption + Mitigtion However, there is limited informtion on the mitigtion nd/or emission potentil of CA-bsed frming systems in SSA

Multiple Sources nd Sinks, Adpttion nd Livelihood options in Lndscpes Csh crop N 2 O Diversifiction/Intensifiction Firewood C sequestrtion Psture C sequestrtion White = Livelihoods Red = Mitigtion Yellow = Adpttion Food crop Food/csh CH 4 Insurnce Kptumo, Keny (Photo Credit: Rosenstock. T)

Sources nd Sinks of GHGs nd Adpttion Options in Agriculturl Lndscpes Lndscpe or system components Source Sinks Adpttion/ Livelihoods CO 2 N 2 O CH4 Biomss Soil C Products Animl + - +++ +++ Psture/mnure deposited Stored mnure ++ +++ + ++ ++ + Perennil crops + +++ ++ + ++ Annul crops ++ + + +++ Trees/Tree crops + ++ +++ ++ +++ Modified from Rosenstock 2013. MICCA Project in Tnzni nd Keny

Climte-Smrt Agriculture Activities Under MICCA - Understnd GHG emissions by vrious cropping systems - Elucidte how yield cn be incresed while GHG emissions cn be reduced - Determine how GHG emissions cn be minimized when frmers dopt climte smrt griculture - Identify bottlenecks in doption to climte smrt griculture

Is CA Climte Smrt Prctices? The Triple Win Climte Smrt prctices should: 1. Increse production nd income 2. Enhnce resilience to climte chnge (Adption) 3. Reduce greenhouse gs emissions (Mitigtion)

Is CA Climte Smrt Prctices? Objective To evlute CA for its climte-smrtness in the highlnds of Estern Tnzni

Study Site Kolero, is found in the southern prt of the Uluguru Mountins, Morogoro region Temperture: 22 0 33 0 C Annul precipittion: 1800 Long rins (Mrch June) Short rins (Oct. Dec.)

Experimentl design: CRD, 5 tretments, 3 replictes

Methodology - Mize plnted in 3 m x 5 m plots with 2 m unplnted buffer strips ccording to tretments - Grin yield Mg/h - Rin use efficiency (yield per drop) - Yield stbility bsed on sesonl vritions (CV, in percent) - CO 2, N 2 O, nd CH 4 fluxes were mesured in the field using sttic chmber techniques - GHG nlysis conducted using gs chromtogrph - Globl wrming potentil (GWP) - Yield-scled GWP (GHG Intensity)

Gs Smpling in Kolero, Tz Withdrwing gs smple from chmber using syringe in Kolero, Tnzni

Lbortory Anlysis of CO 2 CH 4 nd N 2 O Gs chromtogrph (GC) Electron cpture detector (ECD) for N 2 0 detection Flme ionistion detector (FID) for the CH 4 detection A methnizer connected to the FID for CO 2

Mize grin (Mgh -1 ) Results: Mize Grin Yields 44 % (2.7 Mg h -1 ) for fertilizer nd 53 % (2.8 Mg h -1 ) for G. sepium 21 % (2.2 Mg h -1 ) nd 24 % (2.3 Mg h -1 ) for mulching nd lblb, respectively Yield response reflect combined effects of nutrient input nd reduced tillge in CAtretment 6.0 4.0 2.0 0.0 Conventionl Fertilizer Gliricidi Lblb Mulching b bc c b b b b b b 2012SR 2013LR 2013SR 2014LR Growing seson (Yers)

Rin Use Efficiency (kgh -1 mm -1 ) Results: Mize REU Highest RUE vlues in CA with Fertilizer (35%) nd G. sepium (45%) Higher RUE in short rins (5.5-9.3 kg h -1 mm -1 ) compred to 2.6-2.9 kg h -1 mm -1 in long rins Efficient wter use in sesons with low rinflls, possibly due to reduced tillge tretment 16 12 8 4 0 b b b c bc b b Cultivtion Fertilizer Gliricidi Lblb Mulching b b b 2012SR 2013LR 2013SR 2014LR Growing seson (Yers)

Results: Mize Stbility (CV) Trees nd Fertiliztion stbilize yields Conventionl: 72% Mulching: 55% CA plus cover crop: 45%. CA plus fertilizer: 26% CA plus trees: 26%

GHG Fluxes in 2012-13SR Tretments CO 2 -C N 2 O-N CH 4 -C Conventionl 1.85 0.07 48.90 Mulch 2.01 0.14 0.19 Lblb 2.23 0.21 2.27 CA+Fertilizer 2.05 0.16 2.86 CA+Trees 2.30 0.21 1.53 Pr >F 0.8775 0.2245 0.4712

GWP (Mg CO 2 eq h -1 ) in 2012-13 Tretments SR Fllow LR Conventionl Mulch Lblb CA+Fertilizer CA+Trees 9.0 2.3 7.5 7.4 1.9 7.6 8.4 2.1 7.2 7.7 1.9 5.6 8.6 2.0 8.1

GHG intensity (Mg CO 2 eq Mg grin -1 ) Tretments SR LR Annul Conventionl Mulch Lblb CA+Fertilizer CA+Trees 5.1 2.5 7.9 6.3 1.4 7.4 4.3 1.7 6.1 2.1 0.9 3.0 3.8 0.9 4.6

Fluxes, GWP, nd GHG Intensity Lck of significnt difference GHGs fluxes for vrious tretments suggest no climte risk due to intensifiction to increse griculturl productivity The Gliricidi nd fertilizer tretments hd significntly lower globl wrming intensity thn the others nd provide further justifiction for intensifiction s mens to meet food nd climte needs GHG intensity lso suggest tht intensifiction rises yields sustinbly Sustinble intensifiction t the field level my help void emissions from slsh nd burn nd therefore contribute to climte chnge mitigtion

Lnd Use Chnge in Kolero

Kolero, Tnzni Sources nd sink nd livelihood options Agriculturl drivers of deforesttion

- Remnnts of nturl forests mnged under trditionl norms - Lnd tenure is one of the mjor problem fcing the southern Uluguru Mountins - Approximtely, 50% of inhbitnts does not own lnd but rely on either hired lnd or cln lnd for crop frming - Idle lnd due to not been hired or purposeful is left s fllow - Most of current tree cuts re observed in the fllow lnd i.e. indicting both vilbility nd ccess, hence good to improve its mngement for incresing woody stock - Uplnd rice is one of detrimentl nd tree-less crop frming prctice used, hence cusing lots of deteriortion e.g. soil erosion, destocking tree cover

- Overll, negtive chnge of biomss since 1984 to 2002 - Expnsion of croplnd for frming ctivities though opening up of frms not under trditionl protection - Popultion pressure i.e. mostly from locl use, s no commercil chrcol extrction witnessed - Slsh nd burn is still dominnt especilly in opening up fllows - This is ssocited with lesing of crbon (deforesttion) nd nutrient depletion (cusing soil infertility due to nutrient vporiztion)

Conclusions 1. Sustinble intensifiction with CA/CAWT does not seem to pose risk climte in terms on emissions nd hold potentil to stbilize crops production ginst climte vribility 2. There is lnd nd forest degrdtion in forest mrgin vi unstinble griculture