Journal of Geographic Information System, 2012, 4, 462-469
http://dx.doi.org/10.4236/jgis.2012.45050 Published Online October 2012 (http://www.SciRP.org/journal/jgis)
Contribution of MODIS NDVI 250 m Multi-Temporal
Imagery Dataset for the Detection of Natural Forest
Distribution of Java Island, Indonesia
Syartinilia1, Satoshi Tsuyuki2
1Department of Landscape Architecture, Faculty of Agriculture, Bogor Agricultural University (IPB), Bogor, Indonesia
2Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
Email: syartinilia@ipb.ac.id, syartinilia@yahoo.com, tsuyuki@fr.a.u-tokyo.ac.jp
Received July 7, 2012; revised August 5, 2012; accepted September 5, 2012
ABSTRACT
As landmass of the world is covered by vegetation, taking into account phenology when performing land cover classi-
fication may yield more accurate maps. The availability of no-cost Moderate Resolution Imaging Spectrometer
(MODIS) NDVI dataset that provides high-quality continuous time series data is representing a potentially significant
source of land cover information especially for detection natural forest distribution. This study intends to assess the ad-
vantage of MODIS 250 m Normalized Difference Vegetation Index (NDVI) multi-temporal imagery for detection of
densely vegetation cover distribution in Java and then for identification of remaining natural forest in Java from densely
vegetation cover distribution. Result of this study successfully demonstrated the contribution of MODIS NDVI 250 m
for detection the natural forest distribution in Java Island. Therefore, the approach described herein provided classifica-
tion accuracy comparable to those of maps derived from higher resolution data and will be a viable alternative for re-
gional or national classifications.
Keywords: Java; MODIS; Multi-Temporal; Natural Forest; NDVI
1. Introduction
Climate change affects forest both directly and indirectly
through disturbances. Disturbances are a natural and in-
tegral part of forest ecosystems, and climate change can
alter these natural interactions. Such interactions between
climate, disturbances, and forest systems may be critical
in determining how climate change expresses its effects
on forests ([1] Dale et al., 2000) For example, changes in
species diversity are most quickly apparent after a dis-
turbance has cleared the landscape and species adapted to
the new climate become established. Because forests are
so long-lived, it may be that many climate change effects
on forests are most easily to be observed. As we know,
the natural forest is an important source of the world’s
biodiversity.
Forests cover 31% of the world’s surface and contain
vast carbon stocks ([2] FAO, 2010) Alongside carbon
storage, forests also provide important services for the
livelihoods of 1.2 billion people, and are vital for the
survival of a further 60 million indigenous people, who
are completely dependent upon forests ([3] World Bank,
2001). Such services are linked to ecosystem biological
diversity and therefore ensuring the protection of such
diversity within the REDD+ mechanism will be crucial if
forest ecosystems are to remain functional service pro-
viders. The term “REDD-plus” or “REDD+” is now also
used frequently. REDD+ is similar to REDD, but instead
of just covering deforestation and degradation, it includes
other activities, such as the sustainable management of
forests and the enhancement of forest carbon stocks ([4]
Probert et al., 2011). REDD has the potential to make
vast and immediate reductions to greenhouse gas (GHG)
emissions ([5] Lubowski, 2008) and is an important part
of global policies to address climate change. Therefore,
identification the existence of forest cover in large area
may help REDD+ implementation in Indonesia and also
to investigate the impact of climate change to natural
forest.
Recently, vegetation phenology has been found as
fundamental component and a potentially significant
source of successful interpretation of land cover assess-
ment and several researchers have intensively carried out
researches on measuring these variables by remote sens-
ing ([6] Reed et al., 1994; [7] Loveland et al., 2000; [8]
Senay et al., 2000; [9] Knight et al., 2006; [10] Lunetta
et al., 2006). Since most of the landmass of the world is
covered by vegetation, taking into account phenology
C
opyright © 2012 SciRes. JGIS
SYARTINILIA, S. TSUYUKI 463
when performing land cover classification may yield
more accurate maps. However, only a limited number of
studies have explored the potential of employing a com-
plete year of uninterrupted vegetation phenology data as
the basis for land cover classification. Moreover, studies
reporting the use of multi-temporal image data for classi-
fication often include relatively few dates, possibly due
to lack of cloud-free image availability, cost and proc-
essing requirements [(9] Knight et al., 2006). The avail-
ability of no-cost Moderate Resolution Imaging Spec-
trometer (MODIS) NDVI dataset that provide high-
quality continuous time series data is representing a po-
tentially significant source of land cover information
especially for identifying natural forest distribution.
This study intends to assess the advantage of MODIS
250 m Normalized Difference Vegetation Index (NDVI)
multi-temporal imagery for detection of densely vegeta-
tion cover distribution in Java and then for identification
of remaining natural forest in Java from densely vegeta-
tion cover distribution.
2. Methodology
2.1. Study Area
The target area is whole Java Island which covered about
132,000 km2 and administratively divided into four
provinces (Banten, West Java, Central Java, and East
Java), one special region (DI Yogyakarta), and one spe-
cial capital district (Jakarta) (Figure 1).
This Island is a good model for investigating the im-
pact of climate change to the existing natural forest dis-
tribution. Natural forests in this island have been gener-
ally cleared and remnants are now confined to mountain
areas. Although legally protected, these forests are used
by local people for products like firewood, timber, food
and fodder ([11] Whitten et al., 1996).
2.2. Methods
The general approach in this study will be consisted of
the following steps: image pre-processing, threshold se-
lection techniques, natural forest mask creation, natural
forest possibility and accuracy (Figure 2).
2.2.1. Image Pre-Processing
The multi-temporal images used in this study were ac-
quired from the NASA Terra satellite’s Moderate Resolu-
tion Imaging Spectroradiometer (MODIS) sensor. These
data can be ordered directly through the EOS Data Gate-
way (https://lpdaac.usgs.gov/lpdaac/get_data/data_pool).
The MODIS NDVI 250 m product (MOD13Q1) provided
the needed vegetation phenology data. Although MODIS
NDVI scenes (16-day composites were acquired for cal-
endar years 2000 through 2004, only the 2002 data (n =
22) were directly used for the forest cover analysis. Two
tiles were needed to cover entire Java Island (Tile 28 &
29).
Mosaic of the two tiles was created and subsequently
resampled using a nearest neighbor operator. In this
study, 250 × 250 m pixel size was used. MODIS NDVI
data pre-processing was conducted to provide a filtered
(abnormal data removed) and cleaned uninterrupted data
stream to support multi-temporal analysis.
This process is composed of the following three steps:
local maximum fitting (LMF), harmonic analysis and
data reconstruction which is adopted from [12] Wada and
Ohira (2004) and aims to reconstruct time-series data
without cloud, noise and gap. This series of process is
called Harmonic Reconstruction and details of each step
re described below. a
(Source: GeoCover Landsat mosaic, S-48-05_2000, S-50-05_2000).
Figure 1. Java Island, Indonesia.
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SYARTINILIA, S. TSUYUKI
464
Figure 2. Flowchart of this study.
Local maximum fitting (LMF) was applied to the
MODIS NDVI 250 m product (MOD13Q1) dataset of
one year in order to exclude apparently abnormal data.
This is the method to obtain the maximum value A of
four points before continuous time-series data (t1 to t4)
and the maximum value B of four points after continuous
time-series data (t4 to t7), in order to give the minimum
value of both A and B to be the new present (time point 4)
pixel value (Fi gure 3).
Next, Harmonic analysis was conducted for creating
the parameter images of additive, magnitude (size of the
wave) per period, and phase (offset of the wave). The
following parameter images were created using the pe-
riod number of six that are 1-year, 6-, 4-, 3-, 2-, 1-month
period term. As a result, period components were sepa-
rated into magnitude and phase by the unit of pixels. This
process was conducted using the standard application
“Harmonic Series” which was supplied with TNTmips
software (Microimages Inc, USA).
Finally, each parameter of additive, magnitude and
phase obtained by Harmonic Analysis was substituted
into the equation below to perform the reconstruction of
time-series data ([12] Wada and Ohira, 2004; [13] Jaku-
bauskas et al., 2001).
t1-t7: NDVI at each time point; Maximum A = MAX (t1, t2, t3, t4); Maxi-
mum B = MAX (t4, t5, t6, t7); t4’ = MIN (Maximum A, Maximum B); t4’:
NDVI value of time point 4 (present) after filtering.
Figure 3. Local maximum fitting.
Selected vegetation cover
classes
Dense vegetation and sparse
vegetation area
Natural forest mask
Possibility map of natural forest
distribution
Threshold from mean NDVI
MODIS NDVI 16-day, 250m of 2002
(MOD13Q1, Tile 28 & 29)
Mosaic
Unsupervised classification
(Fuzzy C Means)
Resample
Filter and clean data
Subset to study area
Step 1: Local Maximum Fitting
Step 2: Harmonic Analysis
Step 3: Reconstruction of data
Image Pre-processing
Protected areas
Area with elevation > 1000 m
Ground-truth check Accuracy
assessment
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SYARTINILIA, S. TSUYUKI 465

1
2π
cos
on
n
nt
ft ccLn

 


o = Additive; n = 2 × Magnitude (n); n
c c
= Phase
(n); n = Times of harmonic; L = Number of time-series; t
= Times (1 to L).
2.2.2. Threshold Selection
After pre-processing, filtered and cleaned image obtained
were subset to study area. Subsequently for producing
dense vegetation and non-dense vegetation map, combi-
nation of two approaches was applied to MODIS NDVI
images that are threshold from mean NDVI and a classi-
fication result created by Fuzzy C Means (FCM). Ini-
tially, several threshold values from mean NDVI of 70,
75, 80, 81, 82, 83, 84, 85, and 90 were created. Then, the
primary FCM classification results with 50 classes were
overlaid with threshold from mean in order to select the
representative dense vegetation classes of FCM classify-
cation result. After that, 9 × 9 modal filtering to avoid
some small “salt and pepper” pixels was done for filter-
ing selected threshold value image. Finally, the dense
vegetation and non-dense vegetation area map was de-
rived and directly used for creating natural forest mask.
2.2.3. Natural Forest Mask Creation
Natural forest mask creation is composed of three GIS
operations. First, OR operation was applied to protected
areas (PA) and area with elevation >1000 m asl map.
Area with elevation 1000 m and >1000 m have catego-
rized as 0 and 1, respectively. Then, the areas located
inside and outside boundary of protected area have cate-
gorized as 1 and 0, respectively. This operation catego-
rized the area with 1000 m and located outside the pro-
tected area with the value of 0, whereas the remaining
areas with the value of 1. The next operation was replac-
ing the result of first operation from the value 1 become
2. Last operation was using ADD operation for adding
the value obtained from the previous operation and the
dense vegetation and sparse vegetation map. The areas of
sparse vegetation and dense vegetation have a value 1
and 2, respectively. From this operation whole area were
categorized into four values (1 to 4) which are ready to
use for classification of natural forest distribution.
2.2.4. Natural Fo re st Possibility and Accurac y
Assessment
Subsequently, the natural forest mask obtained was
categorized for producing possibility map of natural for-
est distribution (Table 1). Initial classification of natural
forest possibility level was using assumptions as follows:
1) Natural forests in Java had been generally cleared and
remnants are now confined to mountain areas (elevation
>1000 m asl), 2) Remaining natural forests locate in pro-
tected area, 3) Plantation forestry and plantation agricul-
ture (estate) mainly located 1000 m except for tea, cof-
fee and some pine plantation (elevation > 1000 m asl).
For accuracy assessment, we used the field investiga-
tions data which were done in September 2006 and Au-
gust 2007 to identify land use/cover of the area. About
1000 points of landmark data (latitude/longitude) were
recorded using GPS receiver, and digital photographs
were taken at the same time. Subsequently ground truth
data were used as reference data for creating training area
used for accuracy assessment. Overall accuracy and
Kappa accuracy were computed for measuring map ac-
curacy.
3. Results and Discussions
3.1. Harmonic Reconstruction Data
Harmonic reconstruction process was resulted the filtered
and cleaned images. Comparison of raw data, Local
Maximum Fitting data, and cleaned data for one sample
of forest cover is shown in Figure 4. The figure showed
that after filtering and cleaning process, the cleaned and
filtered data have produced. Then, the images can be
sed to proceed for the next analysis. u
Table 1. Initial classification of natural forest possibility level.
Cell
value Characteristics Classification
Natural forest
possibility level
4 Dense vegetation, PA, >1000 m Natural forest 1
4 Dense vegetation, PA, 1000 m Natural forest (lowland forest) 2
4 Dense vegetation, Non PA, >1000 m Natural forest or plantation or estate or agriculture 3
2 Dense vegetation, Non PA, 1000 m Secondary forest, Plantation or estate or agriculture 4
3 Sparse vegetation, PA, >1000 m 5
3 Sparse vegetation, PA, 1000 m 5
3 Sparse vegetation, Non PA, >1000 m
Non-natural forest but still covered by sparse vegetation
such as shrub, bush, etc.
6
1 Sparse vegetation, Non PA, 1000 m Non natural forest Non-natural forest but still covered
by sparse vegetation such as shrub, bush, etc. 7
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SYARTINILIA, S. TSUYUKI
466
Figure 4. Sample pixel profile of NDVI original data, local maximum fitting (LMF) and harmonic reconstruction (HR) data
for forest cover.
3.2. Dense Vegetation Cover Distribution
Dense vegetation and non-dense vegetation area map
resulted from combination of thresholds from mean
NDVI and primary FCM classification result is illus-
trated in Figure 5. Based on this analysis, overlay be-
tween threshold from mean NDVI at 82 and primary
FCM classification result produced the most representa-
tive dense vegetation classes that can be selected and
combined.
The primary FCM classification results with 50 classes
were combined into 2 classes that are dense vegetation
and non-dense vegetation (sparse vegetation). Using this
approach, selection and combination of classes from
primary unsupervised classification result (FCM) can be
done faster, easier and more efficient rather than using
the standard procedure (selection and combination of
each classes using reference data such as topographic
map or aerial photograph). Then, the natural forest dis-
tribution in Java Island was presented as possibility map
of natural forest distribution, which ranked the possibility
level from level 1 to 7 (Figure 6). Distribution area of
each natural forest possibility level was described in Ta-
ble 2.
This study resulted that possibility level 1 to 3 classi-
fied as natural forest remaining in Java Island accounted
for 9731.5 km2 or 7.45% of the Java Island and mainly
distributed in mountainous areas. Some of plantation or
estate or agriculture also may included in area with pos-
sibility level 3 due to the characteristics of this level
having area located outside the boundary of protected
area and elevation > 1000 m asl.
The possibility level 4 was classified as secondary
forest, plantation or estate or agriculture. Spatially, these
areas are located in the surrounding of area with the pos-
sibility level 1 to 3. These areas are mainly found as a
landscape matrix that dominant tropical landscape view
in Java Island. Based on ground truth check, we found
that natural forests remained in Central Java like in Mt.
Semeru, Mt. Ungaran, Mt. Merbabu and Mt. Merapi
were characterized by strip shape, located near the top of
the mountain, and directly bordered with plantation for-
est such as Pine (Pinus merkusii), Dammar (Agathis
dammara), Puspa (Schima wallichii) and Mahogany
(Switenia mahogany). These characteristics are supposed
to be the general condition of the natural forest remnant
throughout the Java Island.
The possibility levels 5 and 6 were classified as non
natural forest but the area located in the surrounding of
natural forests and were still covered by sparse vegeta-
tion such as shrub, bush and so on. The highest patch of
natural forest distribution was found in West Java &
Banten province (4427.9 km2) and then followed by East
Java Province (3964.5 km2). Central Java province had a
smaller patch of natural forest remain in Java Island
(1345.8 km2). Due to active volcanic history and there-
fore volcanic ash, Central Java is a very fertile region for
agriculture especially in Mts. Dieng, so that this area was
cultivated for upland farming and there was only tiny
patch of natural forest remnant.
The possibility levels 5 and 6 were classified as non
natural forest but the area located in the surrounding of
natural forests and were still covered by sparse vegeta-
tion such as shrub, bush and so on. The highest patch of
natural forest distribution was found in West Java &
Banten province (4427.9 km2) and then followed by East
Java Province (3964.5 km2). Central Java province had a
smaller patch of natural forest remain in Java Island
(1345.8 km2). Due to active volcanic history and there-
fore volcanic ash, Central Java is a very fertile region for
agriculture especially in Mts. Dieng, so that this area was
Copyright © 2012 SciRes. JGIS
SYARTINILIA, S. TSUYUKI 467
Figure 5. Dense vegetation and non-dense vegetation map.
Figure 6. Possibility map of natural forest distribution.
Table 2. Distribution area of natural forest possibility level.
Natural forest
Possibility level Characteristics Classification Area (km²) %
1 Dense vegetation, PA, >1000 m asl Natural forest
2 Dense vegetation, PA, 1000 m asl Natural forest (lowland forest)
3 Dense vegetation, Non PA, >1000 m asl Natural forest or plantation or estate
or agriculture
9731.50 7.45
4 Dense vegetation, Non PA, 1000 m asl Secondary forest, Plantation or estate
or agriculture 25708.38 19.67
5 Non-Dense vegetation, PA, >1000 m asl
6 Non-Dense vegetation, PA, 1000 m asl
7 Non-Dense vegetation, Non PA, >1000 m asl
Non natural forest but still covered by
sparse vegetation such as shrub, bush, etc. 8523.31 6.52
8 Non-Dense vegetation, Non PA, 1000 m asl Non natural forest 86709.63 66.36
Total 130672.82 100.00
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SYARTINILIA, S. TSUYUKI
468
Table 3. Accuracy assessment on possibility map of natural forest distribution.
Ground truth classes
Classification Natural forest
possibility level Non
forest Shrub,
bush Secondary forest, plantation,
estate, agriculture Natural
forest
Total User’s
accuracy
(%)
Non forest 7 291 1 0 32 324 89.81
Shrub, bush 5, 6 7 199 10 10 226 88.05
Secondary forest, plantation,
estate, agriculture 4 18 0 52 0 70 74.29
Natural forest 1, 2, 3 0 20 0 456 476 95.80
Total 316 220 62 498 1096
Producer’s accuracy (%) 92.09 90.45 83.87 91.57
Overall accuracy = 91.06%; Kappa accuracy = 86.70%.
cultivated for upland farming and there was only tiny
patch of natural forest remnants.
However, the natural forest area found in this study
was lower than classification result from Indonesian [14]
Ministry of forestry (2002), which was derived from the
analysis using Landsat ETM+ of 1999-2000. They clas-
sified forested area in Java about 23,486 km2 or 17.6%.
The apparent discrepancy probably caused by different
definition of “forested area” used in their classification.
Plantation area was included as forest in their calculation
while in this analysis it was excluded. In the other source,
Regional Physical Planning Project for Transmigration
([15] RePPProt, 1989) classified forest area about 12,450
km2 or 9.5% of Java Island. Similar with this study,
RePPProt also excluded plantation and estate when they
calculated the forest area. Generally, this classification
result is comparable to both sources. Even though ground
resolution used in this study was lower (250 m) than both
sources (30 m), but the classification result is rational
and acceptable.
3.3. Accuracy Assessment
For accuracy assessment, the overall accuracy and Kappa
accuracy were computed for measuring map accuracy.
Table 3 shows accuracy assessment for the possibility
map of natural forest distribution in Java Island. Overall
accuracy was 91.06% and Kappa accuracy of 86.7%,
which seemed to be acceptable.
The main misclassification appears between the “natu-
ral forest” and “shrub or bush” and vice versa. The tran-
sition of shrub or bush to be a forest in natural succession
process and most of them located in the surrounding of
natural forest contributed most to this misclassification.
The reason for the misclassification between “secondary
forest, plantation, estate and agriculture” and “non for-
est” lies in the harvest activity that caused the land is not
covered by any vegetation for a certain period before the
land is ready to plant again.
4. Conclusion
This study successfully demonstrated identification of
natural forest distribution in Java for 2002 using MODIS
NDVI 250 m multi-temporal imagery. The approach de-
scribed herein provides classification accuracies compa-
rable to those of maps derive from higher resolution data.
Given that accuracy results are comparable, data vari-
ability is greater, costs are lower, and the approach is
simpler than other techniques typically used in large pro-
jects. Moreover, the methodology provided in this study
may offer a viable alternative for land cover change de-
tection using multi-year MODIS NDVI dataset for re-
gional or national land cover classification.
5. Acknowledgements
The authors wish to express sincere thanks to Mr. Yukio
Wada and Mr. Wataru Ohira (Japan Forest Technology
Association) for sharing the SML program for Harmonic
Reconstruction Data. We would like to thank the Centre
of Environmental Research (PPLH-IPB) for giving us an
opportunity to get the research fund. Osaka Gas Founda-
tion partially founded this research.
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