Net Primary Production Spatial Distribution in Kalimantan

Abstract

Net Primary Production (NPP) flux was estimated based on the 16-days data of Moderate Resolution Imaging Spectroradiometer (MODIS) for 10 years from 2001 to 2010 by using the National Aeronautics and Space Administration - Carnegie Ames Stanford Approach (NASA-CASA) model. The values of the yearly average of NPP in Kalimantan from 2001 to 2010 were 762.77 gC m-2 yr-1, 703.74 gC m-2 yr-1, 778.68 gC m-2 yr-1, 745.6 gC m-2 yr-1, 797.54 gC m-2 yr-1, 713.27 gC m-2 yr-1, 790.01 gC m-2 yr-1, 768.53 gC m-2 yr-1, 752.94 gC m-2 yr-1, and 867.65 gC m-2 yr-1 respectively. The results have shown that high NPP was found in the forest area with a value from 1,200 gC m-2 yr-1 to 1,600 gC m-2 yr-1. It was followed by palm oil plantation with NPP of 1,000 gC m-2 yr-1 to 1,300 gC m-2 yr-1. For peatland, the value of NPP varied between 200 gC m-2 yr-1 and 600 gC m-2 yr-1. For water body, the results have shown that NPP varied from 0 gC m-2 yr -1 to 100 gC m-2 yr -1. For residential area, NPP was between 0 gC m-2 yr-1 and 700 gC m-2 yr-1. It increased as long as we got far from the center of the city. In term of mining area, the value of NPP was very low varying between 400 gC m-2 yr-1 to 600 gC m-2 yr-1. This high value might be the result from reforestation and from the vegetation surrounding the mining area since the resolution of the MODIS data used is 250-meter. The effect of inter-annual variation of El Nino is not clearly seen. However the NPP is decreasing during El Nino period. On the contrary, NPP is increasing during the La Nina periods. The NPP reached its highest value in March and April during the monsoonal transitional period, and decreased to the lowest in September and October.