Determination of moisture content of the surface fuels depend on meteorological paramaters in normally closure Anatolian black pine (Pinus nigra Arnold) stands

Fuel moisture content of dead fine fuels is one of the most important factors in fire danger rating as it has an important role in fire ignition, fire development and to predict fire behaviour. Moisture content of dead fine fuel directly or indirectly affects fire potential and fire behaviour. Fuel moisture content is generally estimated from relative humidity and temperature and also from rainfall and wind. The moisture content of dead fuel can vary with tree species and fuel types.The principal objectives of this study were to investigate the changes in moisture contents of dead and duff fuels for Anatolian black pine based on weather conditions, and to develop a model to predict fuel moisture content. The study was conducted in pure, normally stocked (~80-90% crown closure), and even-aged Anatolian black pine (P. nigra J.F. Arnold subsp. nigra var. caramanica (Loudon) Rehder) stands. Moisture contents were measured on randomly taken fuel samples. The fuel samples were taken at 13:00 noon Local Standard Time (LST) during May, June, July (only May 09:00 h, 13:00 h and 17.00 h). Relative humidity, air temperature, 24 h accumulated rainfall, and wind speed were also measured.Correlation and regression analysis were carried out to develop a relationship to predict fuel moisture content. The dominant factors influencing moisture content of dead fine fuels (needle, very fine fuels and fine fuels) were 24 h accumulated rainfall and relative humidity of the moisture content of the needle was explained between %52 (P < 0.01) and %88 (P < 0.01) of the by relative humidity and 24 h accumulated rainfall. The main factors affecting were number of days after the rain and 24 h accumulated rainfall on the duff moisture content. Results can be useful for all fire management practices such as planning of prescribed burning, fire danger rating and to understand fire behaviour in Turkey.