Abstract: In order to study the ignition characteristics of surface bryophyte, Dicranum majus and Actinothuidium hookeri, which are widely distributed in northwest Yunnan, were taken as the test objects, and cigarettes and incense were used as ignition sources. The ignition ratio of two bryophytes under different experimental conditions was determined. The multiple linear regression equation was established by SPSS Statistics 27.0, and the regression equation was tested. The results showed that the order of influencing factors on ignition rate of Dicranum majus is: heat release rate > fire burning rate > moisture content > fire diameter > temperature > relative humidity. The order of influence degree of ignition rate of Actinothuidium hookeri is: moisture content > temperature > ignition rate > diameter of fire source > relative humidity > heat release rate. The goodness-fit of the model was 0.820 and 0.893, respectively. Residual analysis showed that the predicting deviation of ignition rate was ±8.895% and ±5.845% respectively. The research results can provide a basis for the management of surface fuels and fire risk warning in northwest Yunnan, and lay a foundation for further identification and evaluation of bryophyte fire risk.

Key words: northwest Yunnan, bryophytes, cigarette, pillar incense, ignition characteristic