ANALYSIS OF FIRE EVENTS AND CONTROLLING FACTORS IN EASTERN INDIA USING SPATIAL SCAN AND MULTIVARIATE STATISTICS
Author: VADREVU, KRISHNA PRASAD
Source: Geografiska Annaler: Series A, Physical Geography, Volume 90, Number 4, December 2008 , pp. 315-328(14)
Vegetation fires are one of the most serious environmental problems in several ecoregions of India. The purpose of this study is to characterize spatio-temporal characteristics of fire events in Orissa state, eastern India. In this study, ATSR satellite remote sensing data have been used to quantify fire events from 1997 to 2006. The spatial scan statistic that quantifies ‘hotspot’ areas of fire risk has been used to identify statistically significant fire clusters during the ten-year time period. To assess the causative factors of fires, topographic, vegetation, climatic, anthropogenic and accessibility factors were used in a robust multivariate statistical framework. Results suggested a clear variation in hotspots of fire occurrences among districts. Of the several districts, the most likely cluster of fire events has been identified in Jharsuguda district followed by secondary clusters in Gajapati, Phulbani, Anugul, Debagarh, Balangir and Raygada. The first three principal components (PCs) from multivariate statistical analysis could explain 70.48% of variance in biophysical and socio-economic indicators of fire events. The loadings were fairly large and highly positive for deciduous forest percentage, elevation, slope mean, aspect mean, and rural population density in the first PC explaining 40.21% of variance. The second PC included drought index, average temperature and illiteracy explaining nearly 19.2% variance. The third PC had a strong positive association with cropped area and forest cover explaining 10.98% of the total variance. Overall, by quantifying the disparities in fire events in space and time, this study demonstrates the utility of the spatial scan statistic in identifying priority areas of fire risk. Our results on fire hotspots and causative factors of risk can guide forest managers toward the best management strategies for avoiding damage to forests, human life, and personal property in the study area.
Document Type: Research Article
Affiliations: Agroecosystem Management Program, Ohio State University, Wooster, USA
Publication date: December 1, 2008