4. Results and Discussion
4.1 LCLUC in the Upper Namphong Watershed 1990, 2001 and 2007
The LCLUC in the Upper Namphong Watershed UNW, based on Landsat TM and SPOT HVR data set acquired in 1990, 2001 and 2007 shows the variation of forest clearing and regrowth. Table 1 shows land cover and land use for 1990, 2001 and 2007 and the comparison of LCLUC in the UNW at the study year. No significant changes in areas of the evergreen forest were found, the decline was 1.17% for 16 years (1990-2007). Considerable changes in the extent of the mixed deciduous and dry dipterocarp forest types for 16 years declining 9.23% and 8.05% respectively. It is worth note that during the period 1990-2001 the area of dry dipterocarp forest expanded by 7.19%. The majority of land use in the area
is paddy field covering an area of over 40% of the total area. However the area of paddy field between 1990-2001 expanded slightly about 0.59% and between 2001-2007 declined by 14.67%. Comparison of the 1990, 2001 and 2007 LCLU maps revealed the distribution of land use type (Fig 4.). A board pattern of LCLU indicated the majority of forest cover found within the national parks and conservation areas with strict control measures. The encroachment of field crop on forest area and upper paddy field increased from 10.26% in 2001 to 19.09% in 2007. Reliability test of the LCLU map checked against the field observation is 70.98% kappa coefficient.