大兴安岭典型林型地表可燃物含水率预测模型

The prediction of moisture content of surface ground fuel of typical forest stand in Daxing' anling mountains

准确地模拟地表可燃物含水率动态变化规律,对于预测预报林火发生或林火行为具有重要意义。应用Nelson模型和Simard模型,以5种典型林型(分别为阴坡落叶松林、阴坡落叶松-白桦混交林、阴坡白桦林、阳坡樟子松林和阳坡白桦林)的地表可燃物为研究对象,分析了气象因子与地被可燃物含水率的相关性,用2015年春季防火期实测数据构建了5种不同林型的可燃物含水率预测模型,并用2016年春季防火期监测数据对预测结果进行验证。结果表明:Nelson模型得出5种林分预测结果为:阴坡落叶松林>阳坡白桦林>阴坡白桦落叶松林>阴坡白桦林>阳坡樟子松林。Simard模型得出5种林分预测结果为:阴坡落叶松林>阴坡白桦林>阳坡白桦林>阴坡白桦落叶松林>阳坡樟子松林。2种模型预测阴坡落叶松的含水率准确率均高于其他4种林分。Nelson模型给出的阴坡落叶松平均绝对误差为0.09,平均相对误差(MRE)为0.09,Simard模型给出的平均绝对误差为0.10,平均相对误差为0.10,Nelson模型略优于Simard模型。研究结果可为该区的森林防火提供快速和准确的火险预测预报,进而为有效防控森林火灾提供重要的技术支撑。

This paper was aimed at improving the forest fire management of Xilinji Forestry Burean in Daxing’anling Mountain of Heilongjiang Province.It is very significant to simulate the dynamics changes of moisture content of surface ground fuel efficiently and accurately,which is of great importance for the prediction of forest fire behavior.Nelson model and Simard model were used to study the moisture content of five typical forest stands(namely,shady slope Larix gmelinii,shady slope Mixture of Larix gmelinii-Betula platyphyll,shady slope Betula platyphylla,sunny slope Pinus sylvestris var.mongolica,shady slope Betula platyphylla).This paper analyzes the correlation between meteorological factor and moisture content of surface ground fuel,based on the measured data of Spring fire prevention period in 2015,five kinds of forecast models of moisture content of different forest types were constructed,and the forecast results were validated by monitoring data of Spring fire prevention period in 2016.Nelson model showed five kinds of forest stand prediction results:shady slope Larix gmelinii>sunny slope Betula platyphylla>shady slope Mixture of Larix gmelinii-Betula platyphyll>shady slope Betula platyphylla>sunny slope Pinus sylvestris var.mongolica.Simard model gives five kinds of forest stand prediction results:shady slope Larix gmelinii>shady slope Betula platyphylla>sunny slope Betula platyphylla>shady slope Mixture of Larix gmelinii-Betula platyphyll>sunny slope Pinus sylvestris var.mongolica.The two models were used to predict the moisture content of the shady slope Larix gemlinii which was higher than that of the other four kinds of forest stands.Nelson model of mean absolute error(MAE)is 0.09,the mean relative error(MRE)is 0.09,Simard model of mean absolute error(MAE)is 0.10,the mean relative error(MRE)is 0.10,and the Nelson model is slightly better than the Simard model.The results of this research can provide rapid and accurate prediction of fire risk for forest fire prevention in this region,and provide important technical support for effective control of forest fires.