Figure 17 shows that the correlation between the average of NPP and precipitation could be considered as low to moderate correlation with a time lag of
four months. The precipitation was four months in advance before the NPP. Changes of NPP are closely correlated with increase temperature and
changing precipitation. Precipitation increases in most Kalimantan areas during La Nina event. Since increase in precipitation is accompanied by increasing
clouds cover and decreasing sunlight and radiation, the increased NPP is small. The decreased NPP also correlated with the rapidly increasing of temperature and
the decreasing of precipitation.
4.5.5 Spatial distribution of NPP in Kalimantan
Figure 18 is the spatial distribution of monthly mean of Net Primary Production.
NPP Mean 2001 NPP Mean 2002
NPP Mean 2003
NPP Mean 2004 NPP Mean 2005
NPP Mean 2006
NPP Mean 2007 NPP Mean 2008
NPP Mean 2009
NPP Mean 2010 Figure 18 Spatial distribution of monthly average of NPP for 10-year period
As shown in the Figure 18, the trend of the average of NPP during the 10- year period is generally stable. It varied from 0 gC m
-2
month
-1
to about 140 gC m
-2
month
-1
. An explanation of why the value of NPP is low mostly in the center of Kalimantan is the geographic and climatic condition in the area. The
geographic condition of Kalimantan shows that it is very mountainous in the center of Kalimantan and the elevation can vary from 0 m to 2,000 m or 2,500 m
above sea level. Figure 19 shows the Digital Elevation Model DEM of Kalimatan. It is
shown that it is very mountainous in the center of the area. This geographic and physic condition of the study area is to be considered in the final result of the NPP.
Figure 19 Digital Elevation Model and 3D view of the study area
September 2006 August 2006
July 2006 June 2006
May 2006 April 2006
March 2006 February 2006
January 2006
October 2006 November 2006
December 2006 Figure 20 Spatial distribution of monthly average of NPP for 2006
Figure 20 shows that there was a dramatically drop of NPP in the month of October 2006. It was related to the low precipitation during this period and the
high temperature. There was also the forest fire in 2006 in Kalimantan. It was reported that the 2006 Southeast Asian haze event was caused by continued
uncontrolled burning from slash and burn cultivation in Indonesia, and affected several countries in the Southeast Asian region and beyond, such as Malaysia,
Singapore, southern Thailand, and as far as Saipan Indon haze spreads to NMI 2006; the effects of the haze may have spread to South Korea NASA 2006.
Local sources of pollution partly contributed to the increased toxicity, particularly in high-pollution areas such as ports, oil refineries, and dense urban areas. In the
highly urbanised and industrialised Klang Valley of Malaysia in particular, the surrounding terrain acted as a natural retainer of polluted air, aggravating the
situation when the haze set in.
Table 6 Burnt area in Kalimantan in September and October 2006 Langner and Siegert 2006
September ha Percent
Wetlands 20,296 1.80
Lowland Forest 79,084
7.03 Peat Swamp Forest
210,001 18.67
Mangrove Forest 717
0.06 Degraded Forest and
Regrowth 354,527 31.52
Cultivation Forest Mosaics 341,058
30.32 DryWet bare Soil;
Grasslands; Agriculture 111,023 9.87
Mountain Forest 49
0,00 Upper Dipterocarp Forest
248 0.02
Freshwater Swamp Forest 7,410
0.66 Total area affected by fire
1,124,811
October ha Percent
Wetlands 21,276 2.28
Lowland Forest 27,779
2.98 Peat Swamp Forest
262,132 28.15
Mangrove Forest 953
0.10 Degraded Forest and
Regrowth 269,348 28.93
Cultivation Forest Mosaics 221,619
23.80 DryWet bare Soil;
Grasslands; Agriculture 114,750 12.32
Mountain Forest 0.00
Upper Dipterocarp Forest 88
0.01 Freshwater Swamp Forest
12,873 1.38
Total area affected by fire 931,194
There was also a link to El Niño NASA 2007. The haze was made worse than during previous occurrences by the El Niño-Southern Oscillation which
delayed the years monsoon season. Fires in Kalimantan produce great amounts of smoke, burn a long time and are difficult to extinguish because they are on
peatland, and once lit the fires can burn for months and release gases that produce sulfuric acid Ghosh 2006. Langner and Siegert 2006 mentioned that big fire
occurred in Kalimantan in October 2006. “…Wednesday night October 11, 2006, big fire occurred in front of the Fire Brigade Manggala Agni of the BKSDA in
Kalampangan village…”. Burnt area in Borneo results were derived from MODIS hotspots 2006, a MODIS based land cover map of the year 2005 and
Landsat ETM images are shown in the table below.
4.6 Validation
