Abstract:
The climate in Sri Lanka is tropical, and consists of various characteristics during
dry and wet seasons. Landslides have become a major natural disaster in the country
especially in Badulla District. The purpose of this study was to identify the
correlation between rainfall and vulnerability for landslides in Badulla District which
is very vulnerable for landslides according to the past evidences. Geographic
Information System (GIS) based Analytical Hierarchical Process (AHP) and
Weighted Overlay techniques were used in this process. The AHP technique was
used in determining the relative importance of the selected criteria i.e., rainfall, slope,
aspect, land use, lithology, population density and the distances from drainage, roads
and pre occurred landslide. All annual rainfall data were considered and averaged
into the four seasons identified in the study. The relationship between annual rainfall
distribution and annual landslide occurrences were studied. Moreover, the
relationship between monthly rainfall distribution and monthly landslide
occurrences were also studied. The correlation between landslide vulnerability and
rainfall was statistically significant. This research predicted the rainfall for the years
2021 and 2022 along with the landslide vulnerability for the same duration. These
findings may be very useful for general public as well as disaster management related
authorities in their decision making and other activities.
