Recent Study on National Deforestation Estimate

Roundtable Discussion UKP4

Jakarta, April 15, 2023

Arief Wijaya1, Lou Verchot1, Daniel Murdiyarso1, Martin Herold2, Arild Angelsen3, Erika Romijn2 and John-Herbert

Ainembabazi3

1 Forest and Environment Programme, Center for International Forestry Research (CIFOR), Bogor, Indonesia

2 Center for Geo-Information Science, Wageningen University, Wageningen, The Netherlands

3 Department of Plants and Environmental Sciences, Norwegian University of Life Sciences (UMB), Oslo, Norway

Purpose of the study

Estimation of future carbon emissions from LULUCF sector is yet challenging for Indonesia

Opportunity: Indonesia has several spatially explicit deforestation maps/estimates

Objective of the talk: to share our approach to improve the reliability of national deforestation estimate

Materials

Land cover map of MOF (2000-2012)

Annual deforestation map of University of Maryland (2000-2010)

Land cover change map of CRISP (2000-2010)

Stratified sample of land cover change map of EU-JRC (2000-2010)

Forest definitions

Source: Romijn, et.al, (2013)

Statistics of deforestation and forest degradation

Source: Romijn, et.al, (2013)

Forest definitions matter!

Distribution of deforestation drivers in Indonesia from 2000 to 2009 based on analysis of follow-up land cover/land use type

Comparison of deforestation estimate

1990-2000

2000-2001

2001-2002

2002-2003

2003-2004

2004-2005

2005-2006

2006-2007

2007-2008

2008-2009

2009-20100

100

200

300

400

500

600

700

800

900

1000

Indonesia MOFOR Indonesia Hansen

Indonesia JRC Indonesia Mean

Annu

al D

efor

esta

tion

(x 1

000

ha)

Validation of deforestation maps of Indonesia

Source: Wijaya, et.al, (In prep)

Deforestation data and forest definitionsSource Resolution

MMU Forest definition

MOFOR Official (Landsat)

6.25 ha Vegetation with canopy cover of more than 30% with minimum area of 0.25 ha and tree height above 5 meter. Plantation forests (e.g. Acacia, Eucalyptus, Teak, etc.) are considered as a forest

MOFOR FAO (Landsat)

6.25 ha Forest is defined by the FAO as land spanning more than 0.5 ha with more than 10% tree canopy cover and trees higher than 5 m (or having the potential to reach a height of 5 m).

CRISP (MODIS)

25 ha Not defined

Hansen (Landsat)

0.09 ha0.36 ha

Forest tree cover was defined as greater than 25% canopy cover and change was measured without regard to forest land use. All tree cover assemblages that met the 25% threshold, including intact forests, plantations, and forest regrowth, were defined as forests.

EU-JRC (Landsat)

5 ha More than 5 m height, forest prop. In polygon (FP)>70, canopy cover (CC)>10

Semi-automatic classification and visual observation? Or different forest definitions?

00-03 03-06 06-09 09-11 11-120

5000

10000

15000

20000

25000

30000

35000

40000

45000

Ministry of Forestry gross deforestation Hansen tree cover loss

Ann

ual g

ross

def

ores

tatio

n/tr

ee c

over

loss

(km

2)

Working definition of different maps

Source Minimum Mapping Unit

(MMU)

Forest Definition Image Classification Approach

Indonesian Ministry of Forestry (MOF)

62,500 m2 Canopy cover > 30%, Total area > 0.25 ha, tree height above 5 meter. Plantation forests (e.g. Acacia, Eucalyptus, Teak, etc.) are included

Visual observation of satellite images, polygon based classification

Hansen, et.al. 900 m2 Canopy cover > 25%, change measured disregard to forest land use. Tree cover assemblages the 25% threshold, including intact forests, plantations, and forest regrowth, were defined as forests

Semi-automatic approach, pixel based classification

Observations so far…

Forest definition matters

Selection of minimum mapping unit is important to determine the smallest size of deforested areas

Different methods to classify satellite images may result in different deforestation figures

Uncertainty of pixel- vs polygon-based classification

Thank you!