Fuel moisture sampling and modeling in Pinus elliottii Engelm. plantations based on weather conditions in Paraná - Brazil

Fuel moisture content is essential to estimate several fire behavior variables. The objective of the present study was to estimate fuel moisture through meteorological variables. The field materials used for this purpose were the accumulated needles found on the ground of a Pinus elliottii Engelm. plantation of the Federal University of Paraná Experimental Station, located in Rio Negro county, Paraná State, southern Brazil (26o04’S lat., 49o45’W long.). To determine fuel moisture content, two sampling methods were tested: the first method consisted in collecting samples of fuel in plastic baskets and subsequently weighing them approximately every two hours, while the second method consisted in collecting, approximately every two hours, a series of different samples directly from the forest floor, and weighing them. All the samples collected on site were then oven dried for moisture determination. Comparing both methods, it was found that the best results were obtained using the samples collected directly from the forest floor and that the best fitting equation included air temperature and wind speed.