Abstract:
The research was concerned with the evaluation of desertification tendency in
Nakhon Ratchasima province. The study was conducted mainly from meteorological,
hydrological, and agricultural data. The data were analysed by GIS. Experts who qualified
professional in meteorology, hydrology, pedology and environment were responsible for
giving scores of weighting and rating. The areas were divided into three catagories as the
high, moderate and low potential areas for desertification values. The areas were analysed
to find out the relations between the rainfall and key factors using the pearson product
moment correlation coefficient. Risk levels of areas from population water use and land
use were evaluated by using matrix coincident
The results found that the high potential areas for desertification were
approximately about 4,774.02 km2 or 23.62%. The moderate potential areas for
desertification were approximately about 12,949.16 km2 or 63.09%. The low potential
areas for desertification were approximately about 2,801.44 km2 or 13.65% of total areas.
With the relations of the potential areas for desertification and trends of rainfall analyzed
by the Pearson Product Moment Correlation Coefficient, it was found that they had
statistic relation at 0.05 level of significance in opposite direction (Pearson correlation :
r = -0.045). This mean that the potential areas for desertification would increase with the
decreasing of rainfall. The analysis of the statistic relations between the potential areas for
desertification and the key factors use in the study found that the most influential factor for
desertification was the rainfall
(r = 0.539). Next was the soil water content (r = 0.527) and the least influential factor for
desertification was the rainy clouds (r = -0.183). With the risk levels to population water
use, it was found that the high potential areas for risks to population water use were
2,576.12 km2 or 12.55%. the moderate potential areas for risks to population water use
were 13,956.49 km2 or 67.99%. the low potential areas for risks to population water use
were 3,992.01 km2 or 19.46%. With the evaluation of the risk levels of areas to land use, it
was found that the high potential areas for risks to land use were about 5,725.83 km2 or
27.89%. the moderate potential areas for risks to land use were about 11,421.31 km2 or
55.65%. the low potential areas for risks to land use were about 3,377.48 km2 or 16.46% of
the total areas.