Maswar, Fahmuddin Agus,

Meine van Noordwijk,Meine van Noordwijk,Supiandi Sabiham

Oteng Haridjaja

IntroductionTropical peat lands conditions

-1985-2000, 20% (1.3% per yr) Indenesian peat forest convertion

Tropical peat lands conditions

peat forest convertion

- Concession Areas in Indonesia: Oil palm (28.009 km2) and HTI (19.923 km2) on peat lands (27% eachs )

- Hot isue 2006: Indonesian GHG, No. 3 of global, (2/3 from peat lands)

(Source: Hooijer et al., 2006)

Tropical Peat Lands Problems

• Deforestation/Conversion• Drainage, (for tree crops)• Forests Fire• Forests Fire

• The carbon losses due to drainage fireThe carbon losses due to drainage, fire, fertilization and their combination are probably a major component in globalprobably a major component in global GHG emission.

• Robust methods are needed to• Robust methods are needed to opportunities for emission reduction of peat lands use for tree crops productionpeat lands use for tree crops production system

Gl b l W i & Cli t ChGlobal impacts Global Warming & Climate Change

COSubsidenceLocal impacts

Global impacts

Compaction Decomposition

CO2Subsidence

C loss

p

Tree Crops

Compaction DecompositionC loss

Tree Crops

Peat Land: • Characteristics,

Drainage: water table• Drainage: water table• Management:

(fertilization, biomass)

Objectives1. To evaluate methods and tools for measurement

carbon content of peat soils.

2. To evaluate C loss in peat lands under several land use and condition

Cot Gajah Mati VillageReseach Location, in West Aceh, Sumatera

Cot Gajah Mati Village

Simpang Village

Desa Suak Raya Village

Desa Suak Puntong Village

Source: ISRI (2006)

P t Peat+ashPeat before fire

Peat+ash after

fireNatural forest

fire

R bbRubber agroforest on peat with fern (Nephrolepis)

Triangulation of methods to estimate C loss

1. Direct flux 2. Subsidence 3. Ash increase measurement = compaction

+ a C-lossindicates C-lossEquationsSnapshot

Subsidence is measu

Equations that use ash as

pin time

is measu-red with metal rod, anchored

internal marker

anchored below the peat; yearly measure-Scaled up ment

pto yearly

flux

Evaluation Tools for maesurement BD

Box sampler 30 x 30 x 10 cm3

y = 0.9988xR2 = 0 970 3

0.35Box sampler 30 x 30 x 10 cm3

Auger(gr c

m-3

) R 0.97

0 2

0.25

0.3AugerRing

Ringers

tool

s (

y = 1.136xR2 = 0.48

0.1

0.15

0.2

Ring

BD

oth

e

y = 1.301xR2 = 0.79

0

0.05

0.1

BD with box sampler 50 x 50 x 10 (gr cm-3)

0 0.05 0.10 0.15 0.2 0.25

BD representatif = Auger value : 1.136BD representatif = Ring value : 1.301

Evaluation methods for determination peat carbon content

x : y = 1.922 ► Konstantay = 0.5203xR2 = 0 618555

60y

and

R 0.6185

45

50

with

Wal

kley

Bla

ck (%

)

35

40

C-o

rgan

ic

80 85 90 95 100

Organic matter with LOI method (%)

%OM (LOI) : %C (Walkley dan Black) ►1 : 0.5203 = 1.922

%C-org = 0.5203 x % OM OM = 1 ~ C-org = 0.5203

( ) ( y )

K = 1,922.(New for tropical peat soils) ; 1,724 (General) ; 12% >

Evaluation for Emisi CO2

No significant different between chamber and LOI methods toestimation CO2 emissionestimation CO2 emission

CO2 N Mean Std. Std. Variances T DF Prob>|T| Deviasi Error

Chb. 41 24,217 22,618 3,532 Unequal -1,423 73,0 0,1588LOI 35 31,469 21,716 3,671 Equal -1,4190 74,0 0,1601

For H0: Variances are equal, F' = 1,08 DF = (40,34) Prob>F' = 0,8135ns

Carbon loss estimates from forests fire:• Simpang village:

92.16 ton C ha-1 ~ 338.23 ton CO2 ha-1

C t G j h M ti ill• Cot Gajah Mati village:133.38 ton C ha-1 ~ 489.50 ton CO2 ha-1

Simpang Before burningp g g

Cot Gajah Mati Before burning

Carbon loss estimates from forest fire withLoss-on Ignition (LOI) methods

Ash content (gr cm-3)Ash content (%)BD (gr cm-3)

Loss on Ignition (LOI) methods

Forestsfire

Natural Forests

Forestsfire

Natural Forests

Forestsfire

Natural Forests

Simpang VillagefireForestsfireForestsfireForests

Cot Gajah Mati Village

0.01180.00198.572.6760.150.07

0.05430.021619.23611.4320.2780.19

j g

Estimates of C- loss up to 13 t C ha-1 yr-1 for young oil palm and less than 2 t C ha-1 yr-1 for y g p yrubber 15 yr age.

Tree EquivalentC lossLocation/ Peat

14 13 84C G

Treeage(yr)

Land useEquivalent

CO2 emission

(t. ha-1 yr-1)

C loss(t. ha-1 yr-1)

Location/Village

Peatthickness

(cm)

-Disturb Forest 12.63.45Simpang1Oil Palm 48.113.1Cot Gajah Mati-Disturb Forests 14.13.84Cot Gajah Mati

1000227227

-Bushes II 32.98.97Simpang-Bushes I 31.48.55Simpang

15Rubber 2.390.651Simpang

349621166

15Rubber 5 821 596Suak Raya10Oil Palm II 40.611.1Suak Puntong10Oil Palm I 38.910.6Suak Puntong

us es 3 98 9S pa g

482118126349

15Oil Palm II 4.341.18Suak Raya15Oil Palm I 25.26.87Suak Raya15Rubber 5.821.596Suak Raya

15424482

• Water table < 52 cm from soil surface, lowest CO2 emissiom for all land useemissiom for all land use

• CO2 emission for rubber agroforestry 15 yr age ~disturb forests

7080

yr-1

) ≤ 52 cm 53 - 89 cm ≥ 90 cm

506070

(ton

ha-1 Forest

BushesRubber

203040

mis

soni

( RubberOil Palm

01020

0 10 20 30 0 0 60 0 80 90 100 110 120 130

CO

2Em y = 1,309x – 90,606

R2 = 0.6273

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Maximum water table (cm)

M i d thMaximum depth of water table is a primary deter-p yminant of net CO2 emissions, but there is anbut there is an apparent ‘time effect’ as well

50% d i

1A

Bulk density of the peat directly influences hydraulic conductivity and water retention curves

50% decrease in hydraulic conductivity 

manifold increase inmanifold increase in water retention

1B

Depth of groundwater table depends on:

water level in the drainage canal, g ,distance to the nearest drain, distance between drains hydraulic conductivity land subsidence

y = 0 8914x

On the

y = 0.8914xR² = 0.8909

deepest peat (> 9 m), the water can

more easily reach the

drain the fil f

Metal rod profile of

ground water table depths is

more ‘flat’

inserted into mineral soil to

measure subsidence

Fertilization can increase C loss and CO2 emission of peat, i.e. in fertilization plot CO2 emission 23 - 48of peat, i.e. in fertilization plot CO2 emission 23 48 ton C ha-1 yr-1 or 84 – 180 ton CO2 ha-1 yr-1 higher than no fertilizer plot

CO2Emission (t ha 1)

No C-loss(t ha 1)

BD (g,cm-3)Ash content (%)Land useLocation

F iliNo

(t. ha-1)

66.318.10.120.133.775.68ForestsSimpang

FertilizerFertilizer (t. ha-1)FertilizerFertilizer

92.125.10.140.186.068.23RubberSimpang

73.920.10.140.196.137.22ShrubSimpang

56.215.30.270.224.576.91Oil Palm IISuak Raya

12032.10.170.173.155.63Oil Palm ISuak Raya

81.722.140.17 a0.18 a4.74 b6.73 aAverage

Note: The data shown in the Table, based on 8 month period field experiment

The difference between C accumulation and C loss for rubber agroforests (>15 year age), and oil palm agroforests (> 15 year age) on shallow peat indicated have a positive valueage) on shallow peat indicated have a positive value

Plant ageLand useC differenceC C lossLocation/

-Forest disturb-2.111.733.84Cot Gajah Mati

a t age(tahun)

(ton ha-1 th-1)

Caccumulation(ton ha-1 th-1)

C loss(ton ha-1

th-1)Village

15Rubber--0.651Simpang-Forest disturb-1.721.733.446Simpang1Oil Palm-13.11013.106Cot Gajah Mati

10Oil Palm I-8.462.1310.594Suak Puntong-Bushes II--8.974Simpang-Bushes I--8.554Simpang

15Oil Palm I-5.441.436.874Suak Raya15Rubber--1.586Suak Raya10Oil Palm II-8.942.1311.074Suak Puntong

15Oil Palm II0.251.431.183Suak Rayay

Note: (-) no data

Time effect on CO2 emissions: negative feedback or resource depletion?

Highlights from the research:

• Carbon loss from peat drained affect by drainage age, and distance from drain (following logarithmic pattern).and distance from drain (following logarithmic pattern).

• Carbon accumulation from the biomass ’waste’ 7 – 75%equivalent 32 – 342 gr C per kg biomass. F tili ti i C l i (23 49 t C h 1 1• Fertilization increase C loss i.e. (23 - 49 ton C ha-1 yr-1

or 8.02 – 180 ton CO2 ha-1 yr-1 ) higher than no fertilizer.

• Forests fire was one of the higest carbon emission frompeat drained : 92.16 – 13.,38 ton C ha-1 or 338.23 –489 50 ton CO2 ha-1489.50 ton CO2 ha

• CO2 emission from Rubber (traditional management) similar with disturbed forest.

SuggestionTo reduce C loss on peat lands for tree cropsTo reduce C loss on peat lands for tree crops production systems: W t t bl t t i i i t• Water table management, to minimize peat decomposition.

• Use plant that can adaptation with peat condition

• Precise technique (time, methods, types and dosage) for fertilizer application.g ) pp

• Fire-free in production (agriculture) systems• Strive for land surface by minimal weeding• Strive for land surface by minimal weeding.

Biomass ’waste’ management on peat survace can accumulate carbon i.e 32 – 342 g of each kg d i ht

Eqn. CO2(g kg-1)

Carbon loss(g kg-1)

Biomass loss(g kg-1)

BiomassLand useLocation

dry weight

1535 95418 51898 1Melastoma998.25 272.00 592.6 LampidingRubberSimpang1618.42440.99924.5 PandanForest disturbSimpang(g kg 1)(g kg 1)(g kg )

1410.53 384.34 823.0 MankireOil PalmCot Gajah Mati1365.61 372.10 798.5 Melastoma1041.04 283.66 618.0 LampidingBushes Simpang1535.95 418.51 898.1 Melastoma

1354.53 369.08 804.1 Lampiding1374.16 374.43 803.5 RubberRubberSuak Raya1592.39 433.89931.1 Melastoma

MankireOil PalmCot Gajah Mati

428.38116.72 254.3Lampiding1497.30 407.98 875.5 Melastoma1475.56 402.06 830.7 Oil PalmOil Palm Suak Raya

1340.98 365.39 784.1 Melastoma1365.43 372.05 768.7 Oil Palm1074.73 292.84 638.0 LampidingOil Palm Suak Puntong

Biomass ‘waste’ performance after 14 months decomposition on peat surfacemonths decomposition on peat surface layer (From: litter bags experiment)

Simpang VillageU

S

Disturb Forest

700

m

00 m

• In 1992 242 Ha area logged over

Disturb Forest

37

230 • In 1992, 242 Ha area logged over

forest + burned, • Fallow until 2006.

E l 2007 D i t t dBushes

• Early 2007, Drain constructed(4m wide x 3 m deep & 3700 m long).g)

• No weeding for rubber (traditional)plantation

Rubber, 15 yr age

Suak Raya Village

U Road

SSampling pointOil Palm, 15 yr age

5

Rubber± 4m peat

Oil palm I± 4m peat depth

140m

50mdepth Oil palm II± 1.25 m peat

depthRubber, 15 yr age

• In 1987, Logged over forest • Drain (1,5m wide and 1,5m deep),

R bb di

Drainage130m

• Rubber: no weeding• Oil Palm : every four month

weedingDrainage

Suak Puntong Village

U

S

50

S

• In 2008, reconstruction drain: 2.5 m wide and 2 m deep

50 mSampling point

p• Oil palm weeding: every six

month and let it in surface Drain

Road

Drain

Cot Gajah Mati Village

M± 3 Km

Drainage

Meulaboh

Oil Palm, 1 yr age

380 m

–C

alangL= 3m

• In 2006, drain constructed Size:3 m wide and 1.5 m deep.

g Road

L= 3mD=1.5m

SSampling Point

Disturb Forest

p• Distance between two drain 380 m. • In 2007, 500 Ha logged over forests

+ burned U

Oil Palm

• In 2008, Oil palm planted.Forest