Badan Penelitian dan Pengembangan PertanianKementerian Pertanian

Science . Innovation . Networkswww.litbang.pertanian.go.id

Global Symposium on soil organic carbonRome, Italy, 21-23 March 2017

Fahmuddin Agus, Maswar, Wahyunto, Anny Mulyani, Neneng L. Nurida, Ratri Ariani, Fitri Widiastuti

Indonesian Agency for Agricultural Research and Development

Peat soil carbon monitoring and management in

Indonesia

Indonesian peatland distributionRitung et al. (2011)

Island Area (ha)

Sumatra 6.436.649Kalimantan 4.778.004Papua 3.690.921Total 14.905.594

Carbon in peat• Relatively conserved under saturated

condition• Decomposition escalates under drained

condition

However, most of the current economically competitive crops are suitable under drained conditions

Objectives Assess:• Assess peat carbon stock • Plot scale C loss • National figure of C loss

1. Peat Carbon Stock Assessment

C-stock = Volume * C density = Depth * area * C-density

Area (ha) by depth distribution

IslandDepth (cm) Area

D1 D2 D3 D4Ha

50-100 100-200 200-400 >400

Sumatera 1,037,034 2,451,669 1,273,692 1,755,823 6,518,218

Kalimantan 1,177,260 1,253,990 1,017,331 1,301,684 4,750,265

Papua 2,400,223 813,446 446,817 - 3,660,486

Total 4,614,517 4,519,105 2,737,840 3,057,507 14,928,969

Overall Mean depth 246±232 cm

6 m 8 m

Peat Carbon density; Sumatra and Kalimantan (Agus et al., 2011)

Mean C stock = 617±184 t (ha.m)-1

Total C-stock = Area * Depth * C density = 22.7±6.8 Pg

2. Plot Scale Monitoring: Subsidence poles

Site and land use Time since drained N Peat depth

  (year)   (cm)W. Kalimantan; Annual crop

rotation6 5 379±18

Riau; Oil palm 9 5 576±46Riau; Shrub,

Rubber 9 6 608±49

Jambi; Oil Palm 11 7 224±29C. Kalimantan,

Rubber 10 10 642±140

Mean 9 33 497±186

Subsidence rate and C lossSite and land use Subsidence

rate

Assumed C loss

40% 60%

  cm yr-1Mg C (ha.yr)-1 Mg C (ha.yr)

W. Kalimantan; Annual crop rotation 4.71±1.26 11.62±3.10 17.42±4.65

Riau; Oil palm 2.78±0.37 6.85±0.91 10.27±1.36Riau; Shrub, Rubber 5.15±2.48 12.72±7.11 19.07±9.16Jambi; Oil Palm 2.49±0.19 6.13±0.48 9.20±0.72C. Kalimantan, Rubber 4.89±1.45 12.07±3.57 18.10±5.35Mean 4.08±1.75 10.07±4.32 15.10±6.49Overall mean1)   11.17±1.42

Lower subsidence for the compacted peat under oil palm plantation

Subsidence rate: 2.49±0.19 to 5.15±2.48 cm/yr

8 m

Undrainable peat

3. C loss monitoring in the national GHG Inventory

Activity data 22 x 22 Land use change matrices 2000-2003; 2003-2006; 2006-2009; 2009-2011; 2011-2013;2013-2015; 2015-2024; 2024-2034

LUC 2013-2015Land use

Primary forest

Forest plantation Plantation Settlement Bareland

Secondary peat forest Peat shrub Annual crop

Multistrata farming Paddy

Primary forest 2,110,820

10 3,092

13,662

13,297

2,173

Forest plantation

6 593,396 4,339 282,979

10,482

6,345

75

191

Plantation 4,112 1,647,039

425

40,684

19,587

1,579

14,268

5,898

Settlement

436

51,418

150

30 9,455

419

434

Bareland

44,866 149,628

450 332,321

224

38,487 5,514

2,839

2,284

Secondary peat forest

16,486

42,142 235,005 3,294,357

48,584

539

100

Peat shrub

32 9,951 215,992

459 224,640

1,921 2,228,089

41,907

25,331

820

Annual crop

468

97,535 1,421

9,332

2,402 187,255

23,094

17,186

Multistrata farming

696

42,060 1,733

4,602

134

8,700

4,592 511,556

3,714

Paddy

34,745 4,327

2,068

191

21,020

9,429 287,945

LUMENS (http://www.worldagroforestry.org/output/lumens)

Land use change trend

Forests Plantation forest

Plantations Degraded lands

Other agriculture

Others -

1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000 7,000,000 8,000,000 9,000,000

Series1

Series2

2006

2015

Emission FactorDrössler et al. 2014 (IPCC 2006 refinement: Wetlands)

Land use Emisi (Mg CO2 ha-1 yr-1)

Remarks

Primary forest 0 IPCC (2006)Forest plantation (Acacia) 73 IPCC (2014)Oil palm plantation 40 IPCC (2014)Settlement 35 Assumed the same grassland Bareland 51 IPCC (2014)Secondary peat forest 19 IPCC (2014)Peat shrub 19 IPCC (2014)Annual crops 51 IPCC (2014)Multistrata farming 51 IPCC (2014)Paddy 34 IPCC (2014)…

Based on research in Indonesia and Malaysia Tier 2

Mitigation ScenariosBy modifying the projected land use change matrices

• BAU• Scenario 1: No plantation expansion on peat

forests • Scenario 2: S1 + no plantation even on peat

shrub (natural regrowth)• Scenario 3: S2 + rewetting of 40% of current

degraded peat (shrub, bareland, grassland)

Annual peat carbon loss through emissions

2000-2003

2003-2006

2006-2009

2009-2011

2011-2013

2013-2015

2015-2024

2024-2033

-

20,000,000

40,000,000

60,000,000

80,000,000

100,000,000

120,000,000

140,000,000 BAU Scenario 1 Scenario 2Scenario 3

BAU, Scenario 1 (no plantation expansion on peat forests), Scenario 2 (Scenario 1 and no plantation expansion on degraded forests, Scenario 3 (Scenario 2 and rewetting of 40% of remaining degraded forests

Land cover in 2015 and annual peat C loss from LULUC into several land cover in 2006-2015

18.5768863643941; 20%

9.76276901279428; 10%

22.5244293818831; 24%

27.399835224

965; 29%

13.856513208

597; 15%

0.893670767125358; 1%

ForestsPlantation forestPlantationsDegraded landsOther agricultureOthers

6.42833358239697; 43%

0.675796256781003; 5%

2.26276648061024; 15%

3.90925673359383; 26%

1.19833755694929

; 8%0.44139399038

3456; 3%

Area (Mha) Peat C loss (Tg/yr)

Degraded lands: Unproductive, losing high amount of C, fire prone

Degraded lands

Agriculture?Rewetting?

Natural regrowth

Paludiculture Annual crops Perennial cops

Mitigation Options

Usahatani sayuran dan padi hidup subur di lahan gambut

20

Paludiculture

Conclusions The unstable peat carbon needs to be conserved by conserving the remaining forests and raising water table in existing agricultural lands. Rewetting of degraded peatlands reduces peat carbon loss significantly. However, the success of voluntary rewetting depends on research ability to develop economically attractive and high market demand crops suitable for paludiculture system.