中文摘要：

死可燃物含水率预报是森林火险天气预报的重要内容，准确预测死可燃物含水率是做好森林火险天气预报和火行为预报的关键。平衡含水率法预测死可燃物含水率在物理上十分可靠，若研究对象可精确描述，理论上其含水率的预测是准确的。因此，该方法是重要的可燃物含水率预测方法。本文对该方法的理论基础和应用情况进行综述。结果表明：1）平衡含水率的预测模型主要有4种，其中Simard模型、Van Wagner模型和Anderson模型都是统计模型，其应用具有一定的局限性；而Nelson模型为半物理模型，在预测可燃物含水率上的效果好，应用广。2）可燃物类型影响平衡含水率，但具体机理还没有系统研究。3）对时滞的影响因子研究相对较少。可燃物的种类、物理性质对时滞都有影响。4）现有平衡含水率法中，Catchpole等的方法因采用Nelson的半物理模型而具普适性，有良好的应用前途。5）平衡含水率法在实际预测中得到广泛应用，是美国火险等级系统和加拿大森林火险等级系统及其他类似系统中可燃物含水率预测的主要方法。

英文摘要：

Dead fuel moisture content （DFMC） prediction is a very important component in fire danger rating, its accuracy becomes the crucial determination of fire behavior and fire weather forecasting. Methods for predicting DFMC based on equilibrium moisture content （EMC）,are physically precise and reliable if the study objects could be described exactly. Therefore, they are the most important methods in DFMC prediction. The theoretical basis of the methods and their applications are reviewed in the paper. The results indicate as below：l） There are four major EMC models among which Simard model, Van Wagner model and Anderson model are all empirical with limited application, whereas Nelson model is semi-physical one and has been used widely. 2） Although EMC is affected by fuel type, systematic research on this area has not been conducted yet. 3） Although few studies on factors affecting timelag have been carried out, it is still sure that fuel types, fuel physical characteristics can affect fuel timelag. 4） Catchpole et al. method,which was based on Nelson model, has been used widely and opened up a vast range of prospect for making use of EMC ＂and timelag.5） EMC and timelag had become the foundation for DFMC prediction in NFDRS of the United States and CFFDRS of Canada and other like systems.