Assessment of causes that contribute to the occurrence of plantations forests fires in Niassa Province, North of Mozambique

Although, Niassa province has natural potential for exotic plantations introduction, forest fires have proved to be a very compromising factor in attracting investments for commercial forestation. Only in two years, fires have devastated approximately 2887.8 ha of Pinus sp. and Eucalyptus sp. of the Chikweti Forests Company. This research was conducted in order to assess the main causes that contribute to the fire occurrence in three Niassa’s districts, where the company Chikweti Forest of Niassa operates. Two year (2010 and 2011) of weather data (temperature, precipitations and relative humidity), have shown favorable conditions for fire occurrence. Data on fire occurrences collected by Chikweti Fire Monitory Center has shown that, arson fires were most predominant, followed by clearing-fields fires. The chi-square test (P < 0.01) showed that the causes that contributed to the occurrences of fires, in each of the evaluated district were not the same in 2010, but for 2011 it showed the opposite. It also showed that the causes of fire were not associated with daily periods (morning, afternoon and night). Most of the forest fires in the studied period occurred in September and October, independently of causes. Arson fires normally occurred in the night, while the remaining causes tend to occur in the morning and afternoon. Key words: Arson fire, weather condition, householders, forests companies.